In certain warehouse and similar operations, a set of tasks sometimes referred to herein as “line kitting” may be performed to assemble stacked trays of items for further distribution, such as delivery to a retail point of sale. Stacks of trays containing the same type of item may be received, and trays may be drawn from different homogeneous stacks each having trays of items of a corresponding type to assemble a mixed stack of trays, e.g., to be sent to a given destination.
For example, a bakery may bake different types of products and may fill stackable trays each with a corresponding homogeneous type of product, such as a particular type of bread or other baked good. Stacks of trays may be provided by the bakery, e.g., to a distribution center. One stack may include trays holding loaves of sliced white bread, another may have trays holding loaves of whole wheat bread, still another tray holding packages of blueberry cupcakes, etc. Trays may be drawn from the various stacks to assemble a (potentially) mixed stack of trays. For example, a stack of six trays of white bread, three trays of whole wheat, and one tray of blueberry cupcakes may be assembled, e.g., for delivery to a retail store.
While the above example involves trays of different types of baked good, in other line kitting operations stackable trays may hold other products.
In a typical approach, trays are handled by human workers. The trays may include handholds to enable a human worker to grasp and move trays, e.g., by placing the workers hand on or in the handhold. Such work by human workers may cause fatigue or injuries, may take a lot of time to complete, and could be error prone.
Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.
The invention can be implemented in numerous ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer readable storage medium; and/or a processor, such as a processor configured to execute instructions stored on and/or provided by a memory coupled to the processor. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. In general, the order of the steps of disclosed processes may be altered within the scope of the invention. Unless stated otherwise, a component such as a processor or a memory described as being configured to perform a task may be implemented as a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. As used herein, the term ‘processor’ refers to one or more devices, circuits, and/or processing cores configured to process data, such as computer program instructions.
A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.
An autonomous, tray handling, line kitting robot is disclosed. In various embodiments, a line kitting robot as disclosed herein includes a robotic arm having an end effector as disclosed herein comprising structures to grasp a tray of items. In various embodiments, one or more such robots may operate together in a single workspace to grasp trays from source stacks and move them, singly or in groups, to destinations stacks assembled according to invoice, manifest, or other input data indicating the output stacks required to be assembled. In some embodiments, two or more robots as disclosed herein may operate on the same rail or other transport structure. Operation is coordinated to avoid collisions and to make efficient use of all robots to complete an overall set of line kitting tasks, such as to assemble a plurality of output stacks each having a corresponding mix of trays according to input information, such as invoices, manifests, etc.
Various embodiments include an end effector device (also referred to herein as an end effector) to be comprised in, or connected to, a robotic arm to grasp, move, and place one or more trays, items within trays or other receptacles, or other objects. The end effector comprises (i) a first grasping mechanism for grasping at least one first object when the robotic end effector is operated in a first mode, (ii) a second grasping mechanism for grasping a second object when the robotic end effector is operated in a second mode. The second grasping mechanism is robotically positioned in an inactive state when the robotic end effector is controlled to operate in the first mode. The second grasping mechanism is robotically positioned in an active state when the end effector is controlled to operate in the second mode.
Various embodiments include a robotic end effector. The robotic end effector includes a robotically actuated second gripper, a robotically actuated first gripper comprising a first element and second element positioned opposite each other on either side of a central vertical axis of the robotic end effector, wherein the robotically actuated second gripper positioned between the first element and the second element, and a robotically actuated retraction-extension mechanism configured to place the robotic end effector in a first mode of operation in which the first gripper is positioned for use or a second mode of operation in which the second gripper is positioned for use.
As used herein, a first grasping mechanism (which may also be referred to herein as a robotically actuated first gripper) may include a suction-based end effector or other grasping mechanism. In some embodiments, the suction-based end effector comprises a plurality of suction cups. The plurality of suction cups may be controlled collectively, or a subset of the plurality of suction cups may be controlled independent of another subset of the plurality of suction cups. In some embodiments, the suction-based end effector is robotically controlled to pick one or more items from, or place one or more items in, a tray or other receptacle within a workspace of a robot.
As used herein, a second grasping mechanism (which may also be referred to herein as a robotically actuated second gripper) may include an end effector comprising a plurality of gripper arms that picks up a tray (or other item or receptacle) by gripping the sides or bottom of the tray. In some embodiments, one or more gripper arms of the second grasping mechanism are movable with respect to a mount to which the end effector is connected to a robotic arm. As an example, the one or more movable gripper arms may be robotically controlled to close a grip on the tray (e.g., in connection with picking up the tray) or to open a grip with respect to the tray (e.g., in connection with releasing the tray at a destination location). For example, the second grasping mechanism may include an active arm and a passive arm, and the active arm may be robotically controlled to adjust the grip/release of a tray.
Various embodiments include a multi-mode end effector that is operable in a plurality of modes. The plurality of modes may include two or more of a first mode, a second mode, and/or a third mode.
In some embodiments, the first mode includes controlling a suction-based end effector comprised in the multi-mode end effector. The multi-mode end effector may be controlled to pick/place items from/to trays or other receptacles, such as in connection with unloading a tray or assembling a kit based on a predefined manifest (e.g., an order being fulfilled). In some embodiments, when the multi-mode end effector is operated in the first mode, a second grasping mechanism (e.g., an end effector comprising gripper arms) may be positioned in an inactive state (e.g., stowed away in a stowed state or a retracted state) such as to expose the suction-based end effector or to enable the suction-based end effector to better grasp items. For example, in response to determining to operate the multi-mode end effector in the first mode, at least part of the second grasping mechanism (e.g., one or more gripper arms) are controlled to transition such part of the second grasping mechanism to an inactive state (e.g., to move the gripper arm to stow the gripper arm in a position that better exposes the suction-based end effector to items to be grasped).
In some embodiments, the second mode includes controlling an end effector comprising a plurality of gripper arms, such end effector being comprised in the multi-mode end effector. The multi-mode end effector may be controlled to pick and place trays or other receptacles, stacking trays in a tray stack or removing an empty tray to expose another tray (e.g., to expose items within the other tray). In some embodiments, when the multi-mode end effector is operated in the second mode, the second grasping mechanism (e.g., an end effector comprising a plurality of gripper arms) may be positioned in an active state (e.g., positioned to a deployed state) such as to enable the end effector comprising a plurality of gripper arms to engage a tray or other receptacle. For example, in the active state, the gripper arms are positioned to provide clearance between a tray engaged by the gripper arms and a suction-based end effector comprised in the multi-mode end effector. In response to determining to operate the multi-mode end effector in the second mode, at least part of the second grasping mechanism (e.g., one or more gripper arms) are controlled to transition such part of the second grasping mechanism from an inactive state to an active state (e.g., to move the gripper arm to deploy the gripper arm in a position that better exposes the gripper arms to engage a tray).
In some embodiments, the third mode includes controlling the multi-mode end effector to use one or more rigid structures attached to the multi-mode end effector to pull or push an object (e.g., an item, a receptacle such as a tray, or a cart such as a cart comprising a stack of trays), etc. Operating the multi-mode end effector according to the third mode enables the robotic arm to adjust a position of an object.
Related art systems for moving receptacles (e.g., trays, totes, containers, etc.) and for moving items comprised within the receptacles use a first grasping mechanism for picking or placing items from/to the receptacles, and a second grasping mechanism for moving receptacles (e.g., an end effector or a conveyor, etc.). The related art systems do not comprise an end effector that includes the first grasping mechanism and the second grasping mechanism (e.g., related art end effectors do not comprise the first grasping mechanism and second grasping mechanism simultaneously deployed on a particular robotic arm. For example, in some related art systems, a second end effector corresponding to the second grasping mechanism is attached to a robotic arm to move the receptacles, and in order to pick/place items from the receptacles the robotic arm is controlled to attach a different end effector (e.g., a first end effector corresponding to the first grasping mechanism) or a different robotic arm already comprising the first end effector. In other words, related art systems decouple the first end effector from a robotic arm to allow a second end effector to be attached to the robotic arm. End effectors according to related art do not comprise a plurality of end effectors or grasping mechanisms and end effectors according to related art do are not multi-modal in which the end effector is operated according to different modes. Accordingly, related art systems or end effectors are inefficient. For example, related art system may use additional robotic arms such that a subset of robotic arms in the system include a first grasping mechanism, and another subset of robotic arms in the system include a second grasping mechanism, and the different subsets of robotic arms are operated together to perform functions enabled by the first grasping mechanism and functions enabled by the second grasping mechanism. As another example, related art systems may require a first grasping mechanism to be detached (e.g., decoupled) from a robotic arm before attaching the second grasping mechanism, such decoupling and coupling of a different end effector introducing latency in performing both functions enabled by the first grasping mechanism and functions enabled by the second grasping mechanism.
In some embodiments, the system includes a control computer(s) to control the multi-mode end effector to autonomously perform operations. The control computer(s) may be further used to control a robotic arm to which the multi-mode end effector such that the control computer(s) collectively control the robotic arm and the multi-mode end effector in connection with performing a set of tasks. Controlling the multi-mode end effector to autonomously perform operations can include using gripper arms (e.g., gripper arms comprised in the second grasping mechanism) to grasp or move trays (or other receptacles or large items), using the gripper arms to push or pull stacks of trays (e.g., a stack of trays disposed on a dolly or other car, using the first grasping mechanism (e.g., a suction-based end effector) to pick and/or place items from/to trays, or to otherwise move smaller items within the workspace, etc.
In some embodiments, the system determines a set of tasks to be performed (e.g., to achieve a higher-level goal such as fulfilling a set of orders) and determines an order in which the set of tasks are to be performed based on a cost function associated with performing the respective tasks within the set of tasks. The system may determine the order in which the set of tasks are to be performed based on a cost associated with transitioning to control the multi-mode end effector between the first mode or the second mode. For example, the system determines the order in which the set of tasks are to be performed based at least in part on a cost associated with transitioning the second grasping mechanism (e.g., an end effector comprising a plurality of gripper arms) between the inactive state and the active state.
In some embodiments, the system obtains from one or more sensors information pertaining to one or more item attributes for an item(s) within the workspace, and information pertaining to a workspace state. The one or more attributes can include an identifier (e.g., a bar code, a serial number, a product number), a shape, a rigidity, a size, a weight, an indication of whether the item is fragile, an indication of whether the item has soft or deformable packaging, etc. The information pertaining to the workspace state can include one or more of a number of trays (or other receptacles, dollies, carts, etc.), a location of the tray(s) within the workspace, an indication of a product or item comprised in the tray, a location of another robotic arm (if any), a location of other objects or humans within the workspace, etc. In response to obtaining the information pertaining to item attribute and workspace state, the system determines a set of M tasks that are to be performed (e.g., to pick and place items in connection with loading or unloading trays, or kitting orders in accordance with an invoice, packing slip, etc.) and determines one or more plans for controlling the robotic arm to pick and place the item(s) corresponding to the set of M tasks. In some embodiments, the system determines an optimal set of next N tasks of the set of M tasks (e.g., N is less than or equal to M) in connection with performing the set of M tasks. For example, the system determines an optimal order in which the set of M tasks are to be performed. The optimal set of N tasks or order of set of M tasks can be determined based on a cost function or otherwise based at least in part on a multi-mode end effector state (e.g., a state of the second grasping mechanism such as whether the gripper arm(s) are deployed or retracted). For example, changing the state of the second grasping mechanism (e.g., between an active state and an inactive state) has certain associated costs such as time, energy, time, etc. Accordingly, the system can determine an optimal order for completing the set of N tasks to minimize the overall cost of performing the set of N tasks or to satisfy a cost criteria (e.g., an overall cost being less than a predefined cost threshold), or to minimize the cost associated with changing the state of the second grasping mechanism while performing the set of N tasks.
In various embodiments, a tray handling robotic system as disclosed herein includes a single rail system occupied by multiple robots coordinating the fulfilment of trays containing packaged food goods, or any other commercial goods or other items. The trays may arrive in stacks of various heights and stacked in various orientations. In some embodiments, the system is divided into two sides: an input side where homogenous stacks come in and an output side that is dedicated to various customers and/or other destinations and is formed by kitting various products from the input side based on an order list, for example.
In some embodiments, multiple robots operate on the same rail or other transport system. For example, two or more robots may operate on the same rail system. Each robot is mounted on a chassis that can be moved along the rail under robotic control, independently of each other robot. The robots are aware of each other and coordinate their motions to optimize order fulfillment. Each robot may use of a single multi-mode end effector designed to grasp trays (e.g., using a second grasping mechanism such as a tray gripper), and to pick or place items from/to trays (e.g., using a first grasping mechanism such as a suction-based end effector). Alternatively, a robot may use a tray gripper that is designed to grasp a plurality of trays at one time. In various embodiments, the gripper is modular and can be adapted to a variety of different trays.
In various embodiments, a robotic system as disclosed herein is configured to pick from stationary stacks of trays (or other receptacles) which sit upon dollies (or other carts). An example of such a robotic system is disclosed in U.S. patent application Ser. No. 16/797,359 filed on Feb. 21, 2020 entitled Robotic Handling of Soft Products in Non-Rigid Packaging, the entire contents of which are incorporated herein by reference for all purposes. Another example of such a robotic system is disclosed in U.S. patent application Ser. No. 17/712,915 filed on Apr. 4, 2022 entitled Robotic Tray Gripper, the entire contents of which are incorporated herein by reference for all purposes. Another example of such a robotic system is disclosed in U.S. patent application Ser. No. 17/219,509 filed on Date entitled Suction-Based End Effector with Mixed Cup Sizes, the entire contents of which are incorporated herein by reference for all purposes.
Although embodiments described herein are provided in the context of a kitting system or picking and placing items from a tray, various embodiments may be implemented in various other contexts such as palletizing systems, singulation systems, etc.
As used herein, depalletization includes picking an item from a pallet, such as from a stack of items on the pallet, moving the item, and placing the item at a destination location such as a conveyance structure. An example palletization/depalletization system and/or process for palletizing/de-palletizing a set of items is further described in U.S. patent application Ser. No. 17/343,609, the entirety of which is hereby incorporated herein for all purposes.
As used herein, singulation of an item includes picking an item from a source pile/flow and placing the item on a conveyance structure (e.g., a segmented conveyor or similar conveyance). Optionally, singulation may include sortation of the various items on the conveyance structure such as via singly placing the items from the source pile/flow into a slot or tray on the conveyor. An example of singulation system and/or process for singulating a set of items is further described in U.S. patent application Ser. No. 17/246,356, the entirety of which is hereby incorporated herein for all purposes.
As used herein, kitting includes the picking of one or more items/objects from corresponding locations and placing the one or more items in a predetermined location in a manner that a set of the one or more items correspond to a kit. An example of a kitting system and/or process for kitting a set of items is further described in U.S. patent application Ser. No. 17/219,503, the entirety of which is hereby incorporated herein for all purposes.
In the example shown, a single rail (e.g., rail 110) is disposed along one long side of the conveyance 106. In this example, two robots, one comprising robotic arm 112 and another comprising robotic arm 114, are mounted movably, independent of one another, on rail 110. For example, each robotic arm 112, 114 is mounted on a self-propelled chassis that rides along rail 110. In this example, each robotic arm 112, 114 terminates with a tray handling end effector (e.g., end effector 116, 118). In some embodiments, end effector 116 and/or 118 implements end effector 300 of
In various embodiments, the tray handling end effector (e.g., end effector 116 or 118) is operated under robotic control to grasp one or more trays from a source tray stack 102, 104. In some embodiments, the tray handling end effector is comprised in a multi-mode end effector attached to robotic arm 112, 114. Examples of a multi-mode end effector include end effector 300 of
In various embodiments, each tray handling end effector 116, 118 (e.g., the second grasping mechanism of the multi-mode end effector) includes one non-moving (“passive”) side member and one movable (“active”) side member. In this example, the movable or “active” side member swings open (position in which end effector 116 is shown), e.g., to enable the end effector to be placed in position to grasp one or more trays, and swings closed (position in which end effector 118 is shown), e.g., to complete a grasp of one or more trays. In other examples, the movable or “active” side member is moved in a lateral translation substantially parallel with the length of a lateral member of the multi-mode end effector from which the “active” and “passive” side members are connected or otherwise extend. In other words, the “active” side member is moved in direction substantially corresponding to the axis of the lateral member in order to widen the grip of the second grasping mechanism or to shorten the grip of the second grasping mechanism when applying a force on a tray to be picked/placed. In various embodiments, a robotic control system (e.g., a computer that controls robotic arms 112, 114, such as control computer 128) controls the end effector to actuate the opening/closing of the end effector such as in connection with grasping or releasing a tray. The robotic control system controls the end effector based at least in part on image data of the work space and/or one or more sensors comprised in (or connected to) the corresponding end effector. In some embodiments, the one or more sensors comprised in (or connected to) the corresponding end effector are configured to: (i) obtain information indicative of whether a grasping mechanism (e.g., an active member of the second grasping mechanism) of the multi-mode effector is in an open position or a closed position, (ii) obtain information indicative of an extent to which the grasping mechanism is open, (iii) obtain information indicative of when the tray (or end effector relative to the tray) is in a position at which the multi-mode end effector is controlled to engage at least one side of the multi-mode end effector (e.g., a passive member or a structure comprised on the passive member) with a hole, a recess, or the a comprised in a side of a tray (e.g., a tray being grasped), (iv) obtain information indicative of when the tray (or end effector relative to the tray) is in a position at which the multi-mode end effector (e.g., a passive member or a structure comprised on the passive member) is engaged with the hole, the recess, or the handle comprised in the a side of a tray, (v) obtain information indicative of whether the grasping mechanism is closed or otherwise engaged with the tray, (vi) obtain information indicative of whether the second grasping mechanism is in an inactive state or an active state, (vii) obtain information indicative of whether an item is grasped by the first grasping mechanism (e.g., the suction-based end effector) of the multi-mode end effector, (viii) obtain information indicative of an attribute of the first grasping mechanism (e.g., a pressure between the suction-based end effector and the item being grasped), (ix) an indication of whether the first grasping mechanism is engaged with an object, (x) obtain information indicative of a state of the first grasping mechanism (e.g., information indicative of the state of the suction cups, such as a position of the suction cups in the case that relative positions of the suction cups can be changed to widen or shorten a distance between at least two suction cups, etc.).
In various embodiments, each end effector 116, 118 includes on each side member one or more protrusions or similar structures of a size and shape such that the protrusion, etc., fits into and, in various embodiments, can be slid under robotic control into holes or other openings in the sides the tray(s) to be grasped. For example, in some embodiments, protrusions on the inner face of the side members, sometimes called “thumbs” herein, are slotted into handholds (e.g., holes sized to accommodate a human hand) on opposite sides of a tray, as described and illustrated more fully below.
In various embodiments, the respective robotic arms 112, 114 are operated at the same time, fully autonomously, to pick trays from source tray stacks 102, 104 and place them on destination tray stacks, such as destination tray stacks 120, 122, in a destination tray stack assembly area on an opposite side of rail 110 from conveyance 106 and source tray stacks 102, 104. The destination tray stacks are assembled, in various embodiments, according to invoice, manifest, order, or other information. For example, for each of a plurality of physical destinations (e.g., retail stores), a destination stack associated with that destination (e.g., according to an order placed by the destination) is built by selecting trays from respective source tray stacks 102, 104 and stacking them on a corresponding destination tray stack 120, 122. Completed destination tray stacks 120, 122 are removed from the destination tray stack assembly area, as indicated by arrow 124, e.g., to be place on trucks, rail cars, containers, etc. for delivery to a further destination, such as a retail store.
Referring further to
In various embodiments, source tray stacks 102, 104 are inserted into a gate or other ingress/control structure at the input end 108 of conveyance 106. Conveyance 106 comprises an apparatus (stack mover) that moves the source tray stacks 102, 104 along the rail 110 to optimize throughput and minimize robot displacement, e.g., by minimizing how far and/or often the robotic arms 112, 114 must be moved along rail 110 to grasp source trays and place them on respective destination stacks. The source tray stacks 102, 104 can come in with trays in different orientations/weights/and weight distribution. The system 100 uses force and moment control to operate robotic arms 112, 114 to insert a thumb or other protrusion gently and securely into a tray and plans its motion and tray trajectory in order to not collide with itself or the environment. In various embodiments, each robotic arm 112, 114 operates in a very tight space of roughly 2.5 m in width and has a very light footprint. The robot utilizes its full workspace and intelligently plans its motion optimizing its grasp. The robot recognizes the need to perform orientation changes and handles that accordingly while avoiding obstacles. The robot moves to the correct output (e.g., destination tray stack 120, 122) corresponding to the right customer while coordinating with the other robots on the rail 110. The robot then uses advanced force control and interactions with the environment to figure out a proper place strategy. The cycle then restarts.
In the example shown in
In various embodiments, image data generated by cameras such as camera 126 is used to move robotic arms and end effectors into a position near a tray or stack of two or more trays to be grasped and picked up from a source stack and/or to position the tray(s) near a destination at which they are to be place, e.g., at the top of a corresponding destination stack. In some embodiments, force control is used, as described more fully below, to complete the final phases of a pick/grasp episode and/or a placement episode.
Although a single camera (e.g., camera 126) mounted to a wall in the workspace of system 100 is shown in
While in the example shown in
In the example shown, at 252 a specific set of one or more items is determined to be moved from a source location to a destination location. For example, the system determines to retrieve the item from a source location (e.g., a kitting shelf, conveyor, etc.) and place an item in a tray or other receptacle. As another example, the system determines to pick the item from a tray and place the item at a destination location (e.g., conveyor, chute, other receptacle, etc.). In some embodiments, a robotic arm has an end effector (e.g., a first grasping mechanism such as a suction-based end effector) that accommodates picking and placing only one item at a time. In other embodiments, a robot has an end effector that can grasp a plurality of items (e.g., by grasping each of the items using a different subset of suction cups of the suction-based end effector).
At 254, a strategy to move to and grasp the item is determined. For example, the robot plans and implements a set of maneuvers to move its end effector (e.g., a suction-based end effector of a multi-mode end effector) to a position above or otherwise near the item(s) to be grasped. As another example, the robot plans and implements an operation to control the end effector to grasp items. The robot controls the end effector (e.g., a multi-mode end effector) to change modes in connection with grasping a tray or item from the tray (e.g., to control the end effector to use a first grasping mechanism or second grasping mechanism based at least in part on whether the end effector is to grasp a tray or an item from a tray, etc.). A strategy to grasp the item(s) is determined and implemented.
At 256, a plan (e.g., trajectory) to move the item(s) to a destination location is determined and executed. The trajectory/plan takes into consideration obstacles in the workspace, such as other items, stacks of trays, and potential conflicts with other robotic instrumentalities, such as another pick/place robot operating in the same workspace (e.g., robotic arms 112, 114 of
At 258, a strategy to place the items at the corresponding destination location (e.g., a destination tray, a conveyor, etc.) is determined and executed.
At 260, results of the pick/place operation are reported, e.g., to a planning process or module. Subsequent iterations of steps 252, 254, 256, 258, and 260 are repeated until it is determined at 262 that processing is done, e.g., all item(s) have been picked and placed (e.g., items corresponding to a manifest such as an order or packing slip, or the tray from which the items are picked is empty, or the tray in which the items are placed is full).
In the example shown, end effector 300 includes a plurality of grasping mechanisms. In some embodiments, end effector 300 comprises (i) a first grasping mechanism corresponding to a suction-based end effector 314, and (ii) a second grasping mechanism comprising gripper arms (e.g., side members). The different grasping mechanisms comprised in end effector 300 is used for different functions or in different modes. Suction-based end effector 314 comprises one or more suction cups 314a, 314b, 314c, and 314d. In some embodiments, end effector 300 is robotically controlled to grasp objects (e.g., trays, items in trays, etc.) based on selectively controlling one or more of the first grasping mechanism and the second grasping mechanism.
As illustrated in
According to various embodiments, side member 306 is movable within a predefined range of motion. As an example, end effector 300 includes one or more stopping mechanisms (e.g., stopper, switch, or the like, or a combination thereof) that restrict movement of the side member 306 to within the predefined range of motion. End effector 300 includes an open-position stopping mechanism that prevents side member 306 from moving in an opening direction past an open position threshold (e.g., 130 degrees relative to a plane/vector along which lateral member 302 extends in a lengthwise direction, or between 30 and 50 degrees relative to a closed position at which active member 306 is substantially normal to the plane/vector along which lateral member 302 extends). End effector 300 includes a closed-position stopping mechanism that prevents side member 306 from moving in an closing direction past a closed position threshold (e.g., about 90 degrees relative to a plane/vector along which lateral member 302 extends in a lengthwise direction, etc.). Various values can be selected for the open position threshold and/or the closed position threshold. In some embodiments, the open position threshold is set based at least in part on an environment in which the robot to which end effector 300 is connected operates. As an example, if a plurality of robots are operating within a relatively close proximity, the range of motion of the side member 306 is based at least in part on a distance between robots or between zones in which the various robots (e.g., neighboring robots) operate. As the side member 306 moves from a closed position to an open position the further the side member 306 extends in the x-direction. In addition, the further the side member 306 is movable from the closed position to the open position, the greater the time required for the robotic system to control to open/close side member 306 in connection with grasping/placing a tray(s). Accordingly, limiting the range of motion of the side member 306 (e.g., to a sufficient open position threshold to permit the end effector to grasp a set of one or more tray(s) with ease) allows the robotic system to operate more efficiently within proximity of other robots (e.g., other robots that are autonomously grasping, moving, and placing trays).
In some embodiments, the open position threshold and/or the closed position threshold are configurable. For example, the one or more stopping mechanisms are configurable and set based on the desired the open position threshold and/or the closed position threshold configuration(s).
The active side thumb 308 and a corresponding structure on the inner face of side member 304, not visible in
Referring further to
In various embodiments, side member 304 is fixedly mounted to lateral member 302. The fixed mounting of the side member 304 enables forces and moments acting on end effector 300 (e.g., on side member 304) to propagate through the frame of the end effector (e.g., lateral member 302 and side member 304) to force sensor 310. For example, the fixed mounting of the side member 304 avoids forces and movements from translating into a movement of other parts of the end effector such as active member 306 when active member 306 is being actuated to move thumb 308 to engage with a tray handle (e.g., to insert thumb 308 into the tray handle).
In the state shown in
In various embodiments, robotic system controls side member 306 (e.g., controls an actuation device to move side member 306) based at least in part on information obtained by one or more sensors, such as a sensor(s) comprised in side member 306 (e.g., thumb 308 of side member 306), a sensor(s) comprised in side member 304 (e.g., a thumb of passive side member), a camera or other sensor comprised on or around the robot to which end effector 300 is connected (e.g., to capture information pertaining to the workspace of the robot), and the like, or any combination thereof. Side member 306 is controlled according to a plan to grasp, move, and/or place a set of one or more trays and the information obtained from the one or more sensors. Side member 306 is further controlled according to obstacles within the workspace of the robot such as another stack of trays (e.g., an adjacent stack), another robot working to remove a tray another stack of trays (or of the same tray).
In various embodiments, tray pick operations as disclosed herein are smooth, gentle, and precise and are tolerant to uncertainty and disturbances. In various embodiments, a pick episode using the second grasping mechanism (e.g., grasping a tray using gripper arms) includes one or more of:
The robot safely aborts the pick if it detects any anomalies related to weight or quality of the trays in the stack or the quality of the stacking itself.
According to various embodiments, end effector 300 is controlled to actuate a second grasping mechanism between an active state (e.g., a deployed state) and an inactive state (e.g., a retracted state). As an example, when end effector 300 is controlled to operate in a first mode (e.g., to use a first grasping mechanism to grasp an item from a tray), the second grasping mechanism is actuated to be configured in an inactive state. During operation in the first mode, end effector 300 is transitioned to the inactive state in which one or more elements of the second grasping mechanism are moved to allow the first grasping mechanism to grasp the object (e.g., the item in a tray, etc.). As another example, when end effector 300 is controlled to operate in a second mode (e.g., to use a second grasping mechanism to grasp a tray), the second grasping mechanism is actuated to be configured in an active state. During operation in the second mode, end effector 300 is transitioned to the active state in which one or more elements of the second grasping mechanism are moved to allow the gripper arms to engage a tray or other object grasped by the second grasping mechanism.
In some embodiments, during operation of end effector 300 in the first mode, end effector transitioned to the inactive state in which elements (e.g., the gripper arms) are moved to a fully retracted state. As illustrated in
Vector/direction 316 illustrates an example of a closed position (e.g., the closed position threshold) corresponding to end effector 300 being operated in the second mode (e.g., in which the gripper arms are positioned in the active state). In various embodiments, the closed position is a configuration according to which side member 306 forms a normal vector (or substantially a normal vector) relative to lateral member 302 and extends away from a part of lateral member 302 that is mounted to a robotic arm. For example, the closed position threshold is 90 degrees (or substantially 90 degrees) relative to a direction along which lateral member 302 extends. As illustrated in
At 402, a determination is made to operate the end effector (e.g., a multi-mode end effector) to pick/place an object. In some embodiments, an object may be a tray, a receptacle, a tote, a box, an item (e.g., an item that can be included in a tray), etc.
At 404, a mode according to which the end effector is to be operated is determined. The system selects, from a plurality of modes, the mode according to which the end effector is to be operated. In some embodiments, the system determines whether to operate the end effector in a first mode according to which a first grasping mechanism (e.g., a suction-based end effector) is used to grasp the object, and/or whether to operate the end effector in a second mode according to which a second grasping mechanism (e.g., an end effector comprising a plurality of gripper arms) is used to grasp the object.
At 406, a determination is made as to whether the end effector is to operated is the first mode. In response to determining that the end effector is to be operated in the first mode at 406, process 400 proceeds to 408. Conversely, in response to determining that the end effector is not to be operated in the first mode at 406, process 400 proceeds to 412.
At 408, a plan for picking/placing an object using a suction-based end effector is determined. In response to determining to operate the end effector in the first mode, the system determines a plan (or strategy) for grasping the object such as an item comprised in a tray or other receptacle and for placing the object at a destination location (e.g., a tray, a conveyor, a shelf, etc.). In some embodiments, in response to determining to operate the end effector in the first mode, the system controls the end effector to transition the second grasping mechanism to an inactive state (e.g., in which the gripper arms are moved to a retracted position). The plan determined for grasping the object can include an operation to transition the second grasping mechanism to the inactive state.
At 410, the suction-based end effector is controlled to pick and place an object at a destination location. The system controls the suction-based end effector to actuate a suction mechanism to apply a suction force between a suction cup of the suction-based end effector and the object to be grasped. The system controls the suction mechanism based at least in part on feedback received by a sensor that detects a suction force (or other attribute of the suction between the suction cup and the object). In some embodiments, controlling the suction-based end effector to pick and place the object comprises controlling a robotic arm to which a multi-mode end effector is mounted to use a suction-based end effector thereof to pick and place the object.
At 412, a plan for picking/placing the object using an end effector comprising gripper arms is determined. In response to determining to operate the end effector in the second mode, the system determines a plan (or strategy) for grasping the object such as a tray (e.g., a tray comprised in a stack of trays, etc.). In some embodiments, in response to determining to operate the end effector in the second mode, the system controls the end effector to transition the second grasping mechanism to an active state (e.g., in which the gripper arms are moved to a deployed position). The plan determined for grasping the object can include an operation to transition the second grasping mechanism to the active state.
At 414, the end effector comprising gripper arms is controlled to pick and place an object at a destination location. The system controls the end effector comprising gripper arms (e.g., the second grasping mechanism) to actuate movement of one or more of the gripper arms to grip the object (e.g., the tray) to be grasped. For example, the system controls to move an active side member to engage the object. The system controls the end effector comprising gripper arms based at least in part on feedback received by a sensor that detects positioning of one or more gripper arms (or thumbs of such arms) relative to the object to be grasped. In some embodiments, controlling the end effector comprising gripper arms to pick and place the object comprises controlling a robotic arm to which a multi-mode end effector is mounted to use the gripper arms thereof to grasp, and pick/place the object.
At 416, a determination is made as to whether process 400 is complete. In some embodiments, process 400 is determined to be complete in response to a determination that no further objects (e.g., trays, items) are to be moved, a tray held by a task table is empty (e.g., in the case of an unloading operation), a tray held by a task table is full (e.g., int eh case of a loading operation), a user has exited the system, an administrator indicates that process 400 is to be paused or stopped, etc. In response to a determination that process 400 is complete, process 400 ends. In response to a determination that process 400 is not complete, process 400 returns to 402.
At 502, a determination is made to operate the end effector (e.g., a multi-mode end effector) in a first mode. In some embodiments, the system determines to operate the multi-mode end effector in the first mode in connection with determining that the object to be grasped is an item to be picked/placed from/to a tray, or otherwise determining that the object is to be grasped with a suction-based end effector.
At 504, information is obtained from one or more sensors. The information indicates whether one or more of the gripper arms is in an active state or an inactive state (or some intermediate state between the inactive state or inactive state). In some embodiments, the system uses the information corresponding to a positioning of the gripper arms in connection with controlling the gripper arms (or second grasping mechanism) to transition to the active state or inactive state according to a mode in which the multi-mode end effector is to be operated.
At 506, a determination is made as to whether the gripper arms are positioned in the inactive state. In response to determining that the gripper arms are not in the inactive state (or determining that the gripper arms are in the active state) at 506, process 500 proceeds to 508 at which a configuration of the gripper arms is adjusted. For example, the system controls to move (or continue to move) the gripper arms to the inactive state (e.g., to the retracted position). In some embodiments, the inactive state corresponds to the gripper arms are positioned in a threshold retracted state such as within a range of angles between the gripper arms and the lateral member (e.g., the gripper arms is deemed to be in an inactive state even if the gripper arms are not fully retracted but are within a threshold of retraction of the gripper arms). Process 500 iterates over 504-508 until the system determines that the gripper arms are in the inactive state.
In response to determining that the gripper arms are in the inactive state at 506, process 500 proceeds to 510 at which the system determines to engage the item such as an item within a tray or other source location (e.g., shelf, conveyor, etc.).
At 512, the system controls to adjust a position of the suction-based end effector (e.g., the first grasping mechanism). The system controls to position the suction-based end effector to engage the item to be grasped. For example, the system moves the robotic arm and end effector to a position at which a suction-cup on the suction-based end effector engages the item.
At 514, the system uses suction control to grasp the item(s) with the suction-based end effector. The system actuates a suction mechanism to apply a suction force between one or more suction cups (e.g., comprised in the suction-based end effector) and the item(s) to be grasped. In some embodiments, the suction-based end effector is controlled to grasp a plurality of items (e.g., to simultaneously move the plurality of items to respective destination location).
At 516, information is obtained from one or more sensors. The information indicates whether the suction-based end effector is engaged with the item(s) to be grasped. For example, the system obtains information pertaining to a suction force between the suction cup(s) of the suction-based end effector and the item(s) to be grasped.
At 518, the system determines whether the item(s) is engaged. For example, the system determines whether the item(s) are securely grasped by the suction-based end effector. In response to determining that the item(s) is not securely grasped (e.g., a suction force between the item and the end effector is less than a threshold suction force, or that the item is not engaged with the suction-based end effector) at 518, process 500 returns to 514 at which the system uses the suction control to adjust/secure engagement/grasping of the item using the suction-based end effector. Process 500 iterates over 514-518 until the system determines that the item(s) is securely grasped by the suction-based end effector.
At 520, the item(s) is moved to the destination location and the suction-based end effector is controlled to place the item(s). In some embodiments, the system controls a robotic arm to move the item to the destination location (or proximity of the destination location) and then controls the suction-based end effector to release the item at the destination location. For example, the system controls the suction-based end effector to reduce/eliminate the suction force between the suction-based end effector and the item(s).
At 552, the system determines to operate the end effector in a first mode. In some embodiments, 552 corresponds to, or is similar to, 502 of process 500 of
At 554, information is obtained from one or more sensors. In some embodiments, 554 corresponds to, or is similar to, 504 of process 500 of
At 556, a determination is made as to whether the gripper arms are positioned in the inactive state. In some embodiments, 556 corresponds to, or is similar to, 506 of process 500 of
At 560, the system determines to engage an item in a tray or other receptacle (or from a source location). The system determines to engage an item based on a manifest (e.g., an order, a packing slip, etc.).
At 562, the system controls to adjust a position of the suction-based end effector (e.g., the first grasping mechanism). in the inactive state. In some embodiments, 562 corresponds to, or is similar to, 512 of process 500 of
At 564, the system uses suction control to grasp the item(s) with the suction-based end effector. In some embodiments, 564 corresponds to, or is similar to, 514 of process 500 of
At 566, information is obtained from one or more sensors. In some embodiments, 566 corresponds to, or is similar to, 516 of process 500 of
At 568, the system determines whether the item(s) is engaged. In some embodiments, 568 corresponds to, or is similar to, 518 of process 500 of
At 570, a determination is made as to whether one or more other items are to be grasped by the suction-based end effector. For example, the system determines whether the suction-based end effector is to simultaneously move a plurality of items to respective destination locations. In response to determining that one or more other items are to be grasped by the suction-based end effector (e.g., for simultaneous movement/placement) at 570, process 550 returns to 560 and process 550 iterates over 560-570 until the system determines that no further items are to be grasped by the suction-based end effector.
At 572, the item(s) is moved to the destination location and the suction-based end effector is controlled to place the item(s). In some embodiments, 572 corresponds to, or is similar to, 520 of process 500 of
At 602, a determination is made to operate the end effector (e.g., a multi-mode end effector) in a second mode. In some embodiments, the system determines to operate the multi-mode end effector in the second mode in connection with determining that the object to be grasped is a tray that is to be picked and/or placed on a stack of trays, etc., or otherwise determining that the object is to be grasped with an end effector having gripper arms.
At 604, information is obtained from one or more sensors. The information indicates whether one or more of the gripper arms is in an active state or an inactive state (or some intermediate state between the inactive state or inactive state). In some embodiments, the system uses the information corresponding to a positioning of the gripper arms in connection with controlling the gripper arms (or second grasping mechanism) to transition to the active state or inactive state according to a mode in which the multi-mode end effector is to be operated.
At 606, a determination is made as to whether the gripper arms are positioned in the inactive state. In response to determining that the gripper arms are not in the active state (or determining that the gripper arms are in the inactive state) at 606, process 600 proceeds to 608 at which a configuration of the gripper arms is adjusted. For example, the system controls to move (or continue to move) the gripper arms to the active state (e.g., to the deployed position). In some embodiments, the active state corresponds to the gripper arms are positioned in a threshold deployed state such as within a range of angles between the gripper arms and the lateral member (e.g., the gripper arms are deemed to be in an active state even if the gripper arms are not fully deployed but are within a threshold of deployment of the gripper arms). As an example, with reference to
In response to determining that the gripper arms are in the inactive state at 606, process 600 proceeds to 610 at which the system determines to engage the object (e.g., one or more trays) with the second grasping mechanism (e.g., the gripper arms).
At 612, the system controls to adjust a position of the end effector having gripper arms (e.g., the second grasping mechanism). The system controls to position the end effector having gripper arms to engage the item to be grasped. For example, the system moves the robotic arm and end effector to a position at which the gripper arm(s) of the end effector engages the object (e.g., the tray).
At 614, the system controls the end effector to grasp the tray(s) with the gripper arms (e.g., the end effector comprising gripper arms). The system actuates one or more of the gripper arms to apply a force between the gripper arm and the tray(s) to be grasped. In some embodiments, the end effector having gripper arms is controlled to grasp a plurality of trays (e.g., to simultaneously move the plurality of items to respective destination location). As an example, the system controls an active arm (e.g., active gripper arm that is movable with respect to the lateral member of the multi-mode end effector) to close and to use force control to slot a thumb of the active arm into a grasp hole of the tray(s).
At 616, the system (e.g., the robot) tests its grasp of the tray(s), and if the grasp is determined at 618 to be secure the robot moves the tray to its destination (e.g., process 600 proceeds to 622). If the grasp is determined at 616 not to be secure, the grasp is adjusted at 622 and tested again at 616. For example, the robot sets the tray back down on the source stack, release the tray, and attempt a new grasp. Or, the robot sets the tray at least partly on the source stack and attempt to adjust its grip without fully releasing the tray, e.g., by using force control to try to slot the passive and/or active side thumbs, respectively, more fully into the tray.
At 620, the tray(s) is moved to the destination location and the end effector is controlled to place the tray(s) (e.g., the gripper arm(s) are controlled to disengage/release the tray(s)). In some embodiments, the system controls a robotic arm to move the item to the destination location (or proximity of the destination location) and then controls the end effector to release the tray at the destination location.
According to various embodiments, process 625 and 650 of process 600 is implemented in connection with 612-614 of process 600.
According to various embodiments, a side member (e.g., passive side member such as side member 304 of end effector 300) comprises one or more sensors. The one or more sensors comprised on the side member are configured to obtain information pertaining to a location of a structure (e.g., a tray) in relation to a position of the end effector (or specifically the passive side member). Examples of information obtained by the one or more sensors include (i) obtain information indicative of when the tray (or end effector relative to the tray) is in a position at which the end effector is controlled to engage at least one side of the end effector (e.g., a passive member or a structure comprised on the passive member) with a hole, a recess, or the a comprised in a side of a tray (e.g., a tray being grasped), (ii) obtain information indicative of when the tray (or end effector relative to the tray) is in a position at which the end effector (e.g., a passive member or a structure comprised on the passive member), etc. The robotic system uses information obtained from the one or more sensors in connection with positioning the passive side member (or the end effector generally). In some embodiments, the robotic system uses the information obtained from the one or more sensors in conjunction with information obtained from a force sensor to control the end effector (e.g., a thumb comprised on passive side member to engage the tray).
In various embodiments, the end effector comprises a first sensor that is configured to obtain information indicative of when the tray is in a position at which the end effector is controlled to engage a passive-side structure (e.g., a thumb disposed on passive side member) with a hole, the recess, or the handle comprised in a structure of the tray. The first sensor is disposed on the passive side member, such as at or near a distal end of the passive side member (e.g., near the bottom or distal end of a fin of the passive side member). As the end effector is moved in proximity to the tray, the robotic system uses information obtained from the first sensor in connection with moving the end effector to engage the tray with the structure on passive-side structure (e.g., a thumb disposed on passive side member). For example, the robotic system uses the information obtained from the first sensor to coarsely position the end effector (e.g., to determine whether the tray is between the side members of the end effector, etc.).
In various embodiments, the end effector comprises a second sensor that is configured to obtain information indicative of when the tray is in a position at which the passive-side structure is engaged with the hole, the recess, or the handle comprised in the structure (e.g., a structure on the side of the tray) The second sensor is disposed on the passive side member, such as in proximity of a structure on the passive side member (e.g., near a thumb of the passive side member or near the top of a fin of the passive side member). As the end effector is moved in proximity to the tray, the robotic system uses information obtained from the second sensor in connection with moving the end effector to engage the tray with the structure on passive-side structure (e.g., a thumb disposed on passive side member). For example, the robotic system uses the information obtained from the second sensor to fine tune a positioning of the end effector.
At 626, information is obtained from a first sensor (s). The information indicates whether a passive arm (passive side member) of the end effector is in proximity of the tray.
At 628, the robotic system determines whether to engage the passive arm. For example, the robotic system uses the information obtained from the first sensor to determine whether to engage the tray with the passive arm. The robotic system determines to engage the tray with the passive arm in response to determining that the plan for moving trays indicates that the tray is to be picked and placed in a destination location, and that the tray is in proximity to the end effector. In some embodiments, the system uses the information obtained from the first sensor to determine whether the tray is between the passive arm and the active arm of the end effector.
In response to determining that the passive arm is not to be engaged (e.g., with the tray) at 628, process 625 proceeds to 630 at which the position of the passive arm is adjusted. The robotic system controls the robotic arm to move the end effector such as closer to the tray. Thereafter, process 625 returns to 626.
In response to determining that the passive arm is to be engaged (e.g., with the tray) at 628, process 625 proceeds to 632 at which the robotic system uses force control to engage the passive arm thumb with the tray. For example, the robotic system uses force control to engage thumb of the passive arm into a structure of the tray (e.g., a hole, recess, handle, etc.).
At 634, information is obtained from a second sensor(s). The information indicates whether the passive arm thumb is engaged with the structure of the tray.
At 636, the robotic system determines whether the thumb of the passive arm is engaged with the tray.
In response to determining that the passive arm thumb is not engaged with the tray at 636, process 625 returns to 632 and 632-636 are repeated. For example, the robotic system further controls to move the end effector to engage the structure of the tray with the passive arm thumb.
In response to determining that the passive arm thumb is engaged with the tray at 636, process 625 proceeds to 638 at which an indication that the passive arm is engaged with the tray. For example, in the case that process 625 is invoked by 612 of process 600, 628 provides an indication to the robotic system (e.g., a process running on the robotic system) that the passive thumb arm is engaged with the tray and that process 600 is to proceed to 606.
According to various embodiments, end effector (e.g., the lateral member, the active arm, or both gripper arms) comprises one or more sensors that obtain information pertaining to a position of the active arm or a plurality of gripper arms (e.g., side members 304, 306 of end effector 300). For example, the system uses the information to determine whether the gripper arm(s) are positioned in an active state (e.g., deployed) or an inactive state (e.g., retracted). The system can control the end effector (e.g., the multi-mode end effector) to operate in different modes or to otherwise transition to different states (e.g., the active state, the inactive state, etc.). In some embodiments, the end effector (e.g., the lateral member, the active arm, or both gripper arms) comprises a sensor(s) that detects whether the active arm is in an open position or a closed position. For example, the sensor is a mechanical limit switch that is configured to obtain information indicative of whether the active side member is in an open position or a closed position. As another example, the sensor is a mechanical limit switch that is configured to obtain information indicative of whether the corresponding gripper arm(s) are in a deployed position or in a retracted state (or in an intermediate state between being fully deployed and fully retracted, etc.). In some embodiments, the end effector (e.g., the lateral member or active arm) comprises a sensor(s) that detects an extent to which the gripper arm is in an open position or a closed position (e.g., the sensor determines a particular orientation of the gripper arm or a particular location of the gripper arm between the open position and the closed position, inclusive). As another example, the sensor is a light sensor. The light sensor is configured to obtain information indicative of whether the active side member is in an open position or a closed position. As another example, the sensor is a light sensor. The light sensor is configured to obtain information indicative of whether the corresponding gripper arm(s) are in a deployed position or in a retracted state (or in an intermediate state between being fully deployed and fully retracted, etc.). The light sensor may be further configured to obtain information indicative of an extent to which the active side member is open (e.g., whether the active arm is partially open such as half-way between the open position and the closed position, etc.). The robotic system uses the one or more sensors (e.g., the sensor(s) that obtains information pertaining to a position of the active arm) to control actuation of an actuator(s) that moves the gripper arm(s) to move (e.g., to move the active arm between the closed position and open position).
In some embodiments, end effector (e.g., the active arm of the end effector) comprises one or more sensors that are used to detect whether the active arm (e.g., a thumb of the active arm) is engaged with a tray (e.g., a structure on the tray such as a hole, a recess, or a handle, etc.). For example, the end effector comprises sensor 315a and/or 315b of end effector 300 illustrated in
At 652, information indicating whether the active arm is open/closed is obtained from a sensor (e.g., a sensor comprised on the end effector such as at the lateral member or active member). The robotic system uses the sensor to obtain information pertaining to a position of the active arm.
At 654, the robotic system determines whether the active arm is in an open position. For example, the robotic system determines whether the active arm is fully open (e.g., opened to the open position threshold). As another example, the robotic system determines whether the active arm is sufficiently open to grasp a tray (e.g., if an adjacent stack prevents/restricts the robotic system from fully opening the active arm).
In response to determining that the active arm is not in an open position at 654, process 650 proceeds to 656 at which the position of the active arm is adjusted. For example, the position of the active arm is adjusted to permit the end effector to grasp the tray (e.g., to ensure clearance of the tray as the end effector is controlled to grasp the tray). The robotic system controls the robotic arm to move the active arm to further open the active arm, or to fully open the active arm. Thereafter, process 650 returns to 652.
In response to determining that the active arm is in an open position at 654, process 650 proceeds to 658 at which the robotic system determines to engage the tray. For example, the robotic system determines to control the actuator to move the active arm to engage the tray with the active arm (e.g., a structure on the active arm such as an active arm thumb).
At 660, force control is used to adjust the configuration of the active arm to the closed position. In response to determining to engage the tray, the robotic system controls the actuator to move the active arm to the closed position.
At 662, information is obtained from sensor(s), the information indicative of whether the active arm thumb is engaged with a structure of the tray. For example, the robotic system obtains information from sensor 315a and/or 315b of end effector 300 illustrated in
At 664, a determination of whether the active arm thumb is engaged with the tray is performed. In some embodiments, the robotic system uses the information obtained from the sensor(s) (e.g., the information indicative of whether the active arm thumb is engaged with a structure of the tray) to determine whether the active arm thumb is engaged with the tray (e.g., whether the active arm thumb is inserted into a hole, recess, or handle of the tray). In some embodiments, the robotic system further obtains information from a force sensor and uses information pertaining to forces acting on end effector in connection with determining whether the active arm thumb is engaged with the tray.
In response to determining that the active arm thumb is not engaged with the tray at 664, process 650 returns to 660 to further adjust the configuration of the active arm. Process 650 iterates through 660, 662, and 664 until the robotic system determines that the active arm thumb is engaged with the tray.
In response to determining that the active arm thumb is not engaged with the tray at 664, process 650 proceeds to 666 at which an indication that the active arm is engaged with the tray is provided. For example, in the case that process 650 is invoked by 612 of process 600, 666 provides an indication to the robotic system (e.g., a process running on the robotic system) that the active thumb arm is engaged with the tray and that process 600 is to proceed to 614.
At 677, a determination is made to place one or more trays. The system determines that the one or more trays are to be placed at a destination location. For example, the system determines to generate a stack of trays by placing one or more trays on top of another tray. As another example, the system determines to move a tray at a top of a stack of trays in response to determining that the top tray is empty (e.g., so as to expose items in the tray beneath the top tray).
At 679, force control is used to adjust a configuration of an active arm of the end effector to an open position. For example, the second grasping mechanism of the end effector is robotically positioned in an active state, and the end effector is actuated to move the active arm of the second grasping mechanism in connection with using the second grasping mechanism to place the one or more trays. In some embodiments, the system controls the end effector to move a plurality of gripper arms in connection with releasing a grip on the tray(s).
At 681, information indicating whether the active arm is open or closed is obtained from one or more sensors. In some embodiments, the system determines whether the gripper arm(s) are in an active state or an inactive state.
At 683, a determination is made as to whether the active arm is open (or retracted). For example, the system determines that the whether the gripper arm(s) are in the active state or the inactive state. The system determines whether the active arm is open based at least in part on the information indicating whether the active arm is open or closed that is obtained from one or more sensors.
In response to determining that the active arm is not open at 683, process 675 proceeds to 685 at which a configuration of the active arm is adjusted. The system controls actuation of the end effector (e.g., the active arm) to move the active arm to the open position. Thereafter, process 675 returns to 681 and iterates over 681-685 until the system determines that the active arm is open.
In response to determining that the active arm is open at 683, process 675 proceeds to 687 at which information indicating whether the active arm thumb is engaged with structure of the tray is obtained from one or more sensors.
At 689, a determination is made as to whether the thumb of the active arm is engaged with the tray. In some embodiments, the system determines whether the thumb of the active arm is engaged with the tray based at least in part on the information indicating whether the active arm thumb is engaged with structure of the tray is obtained from the one or more sensors.
At 691, the system provides an indication that the active arm is disengaged with the tray. In some embodiments, the system provides an indication that the gripper arm(s) are disengaged with the tray (e.g., that the tray is released). The system can provide the indication to the process that invoked process 675 (e.g., 620 of process 600).
According to various embodiments, end effector 300 is a multi-mode end effector. For example, end effector 800 is controlled to operate in a first mode according to which suction-based end effector 830 is used to grasp an object and a second mode according to which second grasping mechanism including side members 804, 806 are used to grasp an object. In the example shown, suction-based end effector 830 is connected to the bottom of lateral member 802. Suction-based end effector 830 includes suction cups 832, 834, 836, and 838. In some embodiments, suction cups 832, 834, 836, and 838 are controlled together (e.g., a single control is used to cause suction for each of suction cups 832, 834, 836, and 838. In some embodiments, suction cups 832, 834, 836, and 838 is controlled individually or in subsets. For example, the system controls suction cups 832, 834 together, and separately control suction cups 836, 838 together. Independent control of at least subsets of suction cups 832, 834, 836, and 838 enables multi-mode end effector 800 to grasp a plurality of items and simultaneously move the items (e.g., in order to place the items at their respective destination locations).
In various embodiments, cylinder 816 (e.g., a pneumatic cylinder) and end rod 818 comprises a cushioned two-way pneumatic cylinder. Activation of the one or more movable side member (e.g., side members 804, 806) is performed by activating the cylinder 816. The end rod 818 of the cylinder 816 is connected to side members 804, 806. Side member 806, which is rotatably connected to lateral member 802 via a pivot joint formed by inserting shoulder bolt 814 through hole(s) 812 and tab or bracket 810, is pushed/pulled by the pneumatic cylinder to close/open the side member 806, respectively. Side member 804 may be similarly connected to lateral member 802 and similarly controlled to move (e.g., to transition between an active state and an inactive state) The actuation of the cylinder 816 is controlled, in various embodiments, by a four-way two-position single solenoid.
In the example shown, end effector 900 further includes guide fins 918 and 920, mounted along the bottom edges of side members 904, 906, respectively. In various embodiments, the guide fins 918, 920 extend along all or a substantial portion of the bottom edge of the side members 904, 906. As shown, each guide fin 918, 920 has a shape that flares outward at the bottom, such that the distance between the respective bottom edges of the guide fins 918, 920 is greater than the width of the tray 914 and the distance between the inner faces of side members 904, 906 when in the closed position, as shown.
Operating end effector 900 in a first mode according to which side members 904, 906 are moved to an inactive state exposes suction-based end effector 930 to grasp an item (e.g., items 922, 924, 926) from tray 914.
In the example shown, end effector 1000 further includes guide fins 1018 and 1020, mounted along the bottom edges of side members 1004, 1006, respectively. In various embodiments, the guide fins 1018, 1020 extend along all or a substantial portion of the bottom edge of the side members 1004, 1006. As shown, each guide fin 1018, 1020 has a shape that flares outward at the bottom, such that the distance between the respective bottom edges of the guide fins 1018, 1020 is greater than the width of the tray 1014 and the distance between the inner faces of the passive and side members 1004, 1006 when in the closed position, as shown.
As shown in
In some embodiments, end effector 1000 comprises one or more vehicle gripper modules 1021a or 1021b on side members 1004, 1006, or guide fins 1018, 1020. The vehicle gripper modules 1021a or 1021b can comprise inner surfaces (e.g., surfaces that engage a tray or vehicle such as a dolly) that have a relatively higher friction than inner surfaces of side members 1004, 1006, or guide fins 1018, 1020. The one or more vehicle gripper modules 1021a or 1021b can be shaped or configured to stably grasp a vehicle (e.g., dolly) when the end effector is controlled to engage the one or more vehicle gripper modules 1021a or 1021b with such a vehicle.
In the example shown, end effector 1000 comprises a suction-based end effector 1030. For example, end effector 1000 is be a multi-mode end effector that is selectively operated in a plurality of modes (e.g., a first mode in which suction-based end effector 1030 is used to grasp an object, a second mode in which side members 1004, 1006 are used to grasp an object, and/or a third mode in which end effector 1000 is controlled to pull/push a tray, a cart, or other object).
In various embodiments, tray place episodes by a single robot tray gripping robot as disclosed herein are smooth, gentle, and precise and tolerant to uncertainty and wobbling. In various embodiments, a place episode includes one or more of:
The robotic system uses sensor(s) 1024 to detect whether tray 1014 is in proximity to end effector 1000 such as in a manner that robotic system can finely control movement of end effector to engage the tray with the structure on side member 1004 (e.g., a thumb on side member 1004). In some embodiments, sensor(s) 1024 obtain information indicative of when tray 1014 is in a position at which end effector 1000 is controlled to engage the passive-side structure with the hole, the recess, or the handle comprised in the tray 1014.
The robotic system uses sensor(s) 1022 to detect whether tray 1014 is engaged by side member 1004 (e.g., by the structure on side member 1004, such as a thumb). In some embodiments, sensor(s) 1024 obtain information indicative of when tray 1014 is in a position at which the passive-side structure is engaged with the hole, the recess, or the handle comprised in the tray 1014. As illustrated in
In some embodiments, the robotic system uses information obtained by sensor(s) 1022 and/or 1024 in connection with determining whether to control the actuator to move one or both side members 1004, 1006 (e.g., to engage tray 1014 with a thumb(s) of side members, 10041006) to grasp tray 1014.
End effector 1000 includes one or more rigid structures on one or more side members (e.g., gripper arms), such as rigid structures 1040a, 1040b of side members 1004, 1006. In some embodiments, the system controls a robot and/or end effector 1000 to use rigid structure 1040a and/or 1040b to move a dolly (or other cart, etc.), to push or pull a tray, etc. As an example, end effector 1000 includes rigid structure 1040 in addition to, or as an alternative to vehicle gripper modules 1021a or 1021b.
Although the examples illustrated in
In various embodiments, the slotting episode (e.g., 1108) serves to ensure the stability of the tray on top of the stack and its proper insertion. After the adjustment in the z axis (up/down) and the y axis (axis along rail along with the trays slot, e.g., the axis into and out of the page as shown in
If the tray is determined to have been securely slotted (1110), the robot releases the tray (e.g., opens one or more of the side members and withdraws the thumb(s) from the hole(s) into which it was inserted) and the process ends. If not (1110), at 1112 the placement is adjusted and tested again at 1108. If after a configured number of attempts the tray cannot be verified as having been placed securely, in various embodiments, the system prompts a human worker to assist it, e.g., by teleoperation or manual work.
In various embodiments, a tray handling robot system as disclosed herein learns and/or is trained to recognize a force sensor reading and/or profile associated with a misalignment as shown in
In various embodiments, one or more robots such as robot 1300 of
In various embodiments, robot 1300 is deployed in a tray handling system as shown in
In various embodiments, the image data is used to do one or more of the following: avoid collisions with other robots, tray stacks, and other items present in the workspace; plan trajectories; and position the end effector 1304 and/or a tray in the grasp of end effector 1304 in at least an initial position under position control. End effector 1304 is a multi-mode end effector comprising a first grasping mechanism (e.g., a suction-based end effector) and a second grasping mechanism (e.g., an end effector having gripper arms). End effector is robotically controlled to operate in one of a plurality of different operating modes, such as a first mode in which an object is grasped using a suction-based end effector, a second mode in which an object is grasped using an end effector having gripper arms, a third mode in which end effector 1304 is used to push or pull an object such as a stack of trays, a cart, a dolly, etc. Various other modes may be implemented.
In some embodiments, the cameras 1318, 1320, 1322, and 1324 are included in a vision system used to control of a robotic tray handling system as disclosed herein. In some embodiments, the vision system is designed to self-calibrate. The robot uses a marker that is installed on one of its joints and exposes the marker to the cameras in the system, e.g., cameras 1318, 1320, 1322, and 1324, which recognize the marker and perform a pose estimation to understand their own pose in world coordinates. The robot plans its motion using collision avoidance to get the marker into a position close to the cameras to get a high-quality calibration.
In some embodiments, a onetime manual process follows the automatic calibration to further ensure the quality of the process. A point cloud is overlaid on top of the simulated graphics of the system and a human operator performs the matching or the rendered graphics of the robot plus environment in a simulator to the point cloud as seen by the camera mounted on the robot. Further verification procedures are also in place to verify perceived depth of objects of known heights in the world frame (coordinates).
In some embodiments, a system as disclosed herein self-calibrates its own dimensions. The robot moves up and down the rail to find the pick and place locations and uses force control to find the coordinates of the input-output slots. It dynamically performs an update. For example, in some embodiments, the system uses specially designed calibration motions (including force control) to find the exact locations of each of the input and the output facings (where stacks of trays exist) referred to as the “layout”, and updates layout values internally that many times reveal variations such as uneven ground surfaces, peripheral installation misalignments. The robot dynamically performs these updates through its lifespan, in various embodiments.
In some embodiments, the vision system approximates the pose of the target tray or the target destination stack to check the robot goal motions. A vision system scheduler guarantees simultaneous checks when it is possible to and both input and output targets are in the field of view.
At 1402, a determination is made to operate the end effector (e.g., a multi-mode end effector) to pick/place an object. In some embodiments, an object may be a tray, a receptacle, a tote, a box, an item (e.g., an item that can be included in a tray), etc.
At 1404, a mode according to which the end effector is to be operated is determined. The system selects, from a plurality of modes, the mode according to which the end effector is to be operated. In some embodiments, the system determines whether to operate the end effector in (i) a first mode according to which a first grasping mechanism (e.g., a suction-based end effector) is used to grasp the object, (ii) a second mode according to which a second grasping mechanism (e.g., an end effector comprising a plurality of gripper arms) is used to grasp the object, and (iii) a third mode according to which a structure of the multi-mode end effector is used to push or pull an object such as a stack of trays, a cart, a dolly, a tray, an item in a tray, etc.
At 1406, a determination is made as to whether the mode according to which the end effector is to be operated is a first mode. In response to determining that the mode according to which the end effector is to be operated is the first mode at 1406, process 1400 proceeds to 1408. Conversely, in response to determining that the end effector is not to be operated in the first mode at 1406, process 1400 proceeds to 1412.
At 1408, a plan for picking/placing an object using a suction-based end effector is determined. In response to determining to operate the end effector in the first mode, the system determines a plan (or strategy) for grasping the object such as an item comprised in a tray or other receptacle and for placing the object at a destination location (e.g., a tray, a conveyor, a shelf, etc.). In some embodiments, in response to determining to operate the end effector in the first mode, the system controls the end effector to transition the second grasping mechanism to an inactive state (e.g., in which the gripper arms are moved to a retracted position). The plan determined for grasping the object can include an operation to transition the second grasping mechanism to the inactive state.
At 1410, the suction-based end effector is controlled to pick and place an object at a destination location. The system controls the suction-based end effector to actuate a suction mechanism to apply a suction force between a suction cup of the suction-based end effector and the object to be grasped. The system controls the suction mechanism based at least in part on feedback received by a sensor that detects a suction force (or other attribute of the suction between the suction cup and the object). In some embodiments, controlling the suction-based end effector to pick and place the object comprises controlling a robotic arm to which a multi-mode end effector is mounted to use a suction-based end effector thereof to pick and place the object.
At 1412, a determination is made as to whether the mode according to which the end effector is to be operated is a second mode. In response to determining that the mode according to which the end effector is to be operated is the second mode at 1412, process 1400 proceeds to 1414. Conversely, in response to determining that the end effector is not to be operated in the first mode at 1412, process 1400 proceeds to 1418.
At 1414, a plan for picking/placing the object using an end effector comprising gripper arms is determined. In response to determining to operate the end effector in the second mode, the system determines a plan (or strategy) for grasping the object such as a tray (e.g., a tray comprised in a stack of trays, etc.). In some embodiments, in response to determining to operate the end effector in the second mode, the system controls the end effector to transition the second grasping mechanism to an active state (e.g., in which the gripper arms are moved to a deployed position). The plan determined for grasping the object can include an operation to transition the second grasping mechanism to the active state.
At 1416, the end effector comprising gripper arms is controlled to pick and place an object at a destination location. The system controls the end effector comprising gripper arms (e.g., the second grasping mechanism) to actuate movement of one or more of the gripper arms to grip the object (e.g., the tray) to be grasped. For example, the system controls to move an active side member to engage the object. The system controls the end effector comprising gripper arms based at least in part on feedback received by a sensor that detects positioning of one or more gripper arms (or thumbs of such arms) relative to the object to be grasped. In some embodiments, controlling the end effector comprising gripper arms to pick and place the object comprises controlling a robotic arm to which a multi-mode end effector is mounted to use the gripper arms thereof to grasp, and pick/place the object.
At 1418, a determination is made to operate the end effector in a third mode. As an example, the system determines to operate the end effector in response to determining that an item to be grasped is best suited for a structure of the end-effector rather than the suction-based end effector. As another example, the system determines to operate the end effector in the third mode in response to determining that an item is to be slightly nudged or moved, or that a stack of trays or a cart/dolly is to be moved/pushed.
At 1420, a plan for pushing and/or pulling an object is determined. The object may be a stack of tray, a cart, a dolly, an item in the workspace, etc. In response to determining to operate the end effector in the third mode, the system determines a plan (or strategy) for moving the object based on nudging or pushing/pulling the object using a part of the end effector such as a rigid structure, a hook, etc. The plan determined for grasping the object can include an operation to transition the second grasping mechanism to the active state.
At 1422, the end effector is controlled to push/pull the object. In some embodiments, the system controls the robotic arm to which the multi-mode end effector is mounted to engage the item using a part of the multi-mode end effector (e.g., a rigid structure, a hook, etc.) and controls the robotic arm to push/pull the object using the multi-mode end effector.
At 1424, a determination is made as to whether process 1400 is complete. In some embodiments, process 1400 is determined to be complete in response to a determination that no further objects, trays, or carts are to be moved (e.g., picked or placed), a tote or other receptacle corresponding to a manifest (e.g., an order) is assembled/packed, a user has exited the system, an administrator indicates that process 1400 is to be paused or stopped, etc. In response to a determination that process 1400 is complete, process 1400 ends. In response to a determination that process 1400 is not complete, process 1400 returns to 1402.
In the example illustrated in
An actuation mechanism (not shown) operatively connected to end effector 1500 actuates a suction for one or more of the suction cups of end effector 1500. In some embodiments, an actuation mechanism actuates a first suction cup independent from actuation of a second suction cup. In some embodiments, a suction cup is actuated according to a set of suction cups to which the suction cup belongs. The actuation mechanism actuates one or more of the suction cups on the end effector 1500 based at least in part on a plan (e.g., a grasping strategy included in a plan for a singulation operation, a plan for a kitting operation, etc.).
In some embodiments, end effector 1520 comprises one or more movable suction cups. Positioning of the movable suction cups is controlled based on an item to be grasped by end effector 1520 or based on a plurality of items to be grasped. For example, positioning of the movable suction cups is controlled based on a plan for grasping one or more items using end effector 1520. A suction cup is moved relative to the face of end effector 1520 to widen the distance between at least two suction cups on end effector 1520, such as in connection with enabling end effector 1520 to grasp two distinct items to allow for simultaneous grasping/moving of the items. A suction cup may also be moved relative to the face of end effector 1520 to shorten a distance between at least two suction cups on end effector 1520, such as in connection with enabling end effector 1520 to grasp a single item using the two suction cups.
In the example shown, end effector 1520 comprises three sets of suction cups: first set 1525, second set 1530, and third set 1535. First set 1525 comprises suction cups 1527, 1529; second set 1530 comprises suction cups 1532, 1534; and third set 1535 comprises suction cups 1537, 1539.
In some embodiments, at least two of the first set 1525, second set 1530, and third set 1535 are controlled independent of one another (e.g., suction can be independently applied to different sets of the three sets of suction cups). In some embodiments, at least two of the first set 1525, second set 1530, and third set 1535 are controlled together (e.g., a collective control is used to apply suction across the suction cups of such at least two sets). In some embodiments, suction for any one set of the three sets of suction cups are independently controlled for the various suction cups in such set or may be controlled on a subset-by-subset basis. For example, with respect to first set 1525, suction cup 1527 is controlled independent from suction cup 1529.
The end effector 1520 is controlled to move one or more suction cups among the various sets of suction cups.
In the example shown in contrast to end effector 1520 of
As illustrated in
In the example shown in contrast to end effector 1520 of
As illustrated in
In some embodiments, a first set of one or more suction cups are moved to increase a distance between such suction cups and the center of the suction-based end effector while a second set of one or more suction cups are moved to decrease a distance between such suction cups and the center of suction-based end effector. With reference to
In the example shown, suction-based end effector 1580 comprises a plurality of suction cups 1527, 1532, 1535. In some embodiments, suction-based end effector 1580 is robotically controlled to change a configuration or relative positioning of at least a subset of the plurality of suction cups 1527, 1532, 1535. For example, suction-based end effector 1580 comprises actuation mechanism 1588 that is configured to change the position/configuration of suction cup 1535. The plurality of suction cups 1527, 1532, 1535 are mounted on mounting plates 1584, 1586 and in response to being actuated, such as by a control signal sent by a control computer, actuation mechanism 1588 is actuated to move mounting plate 1586 relative to mounting plate 1584, which in turn changes the configuration/position of a subset of suction cups (e.g., suction cup 1586) relative to another subset of suction cups (e.g., suction cups 1527, 1532). As illustrated in
Although
At 1602, a determination is made to move a set of N objects using a multi-mode end effector. In some embodiments, the system determines a set of N objects to be moved based on a manifest or order corresponding to a kit of items to be assembled/collected for shipment. A subset of the N objects may be items comprised within one or more trays in the workspace of the robotic arm to which the multi-mode end effector is mounted. Another subset of the N objects may be one or more trays in the workspace, such as a top tray in a stack of trays that is empty or that is emptied while the multi-mode end effector is controlled to grasp items from the top tray, or top tray(s) that are to be moved to expose another tray from which items are to be grasped. The system determines the set of N objects based at least in part on information obtained by one or more sensors disposed within the workspace.
At 1604, an order in which the set of N objects are to be moved is determined based at least in part on a cost function. The cost function is based at least in part on one or more of (i) various operating modes in which the various objects are to be grasped, (ii) respective destination locations of the objects, (iii) respective source locations of the objects, (iv) a location(s) of another object(s) or structure in the workspace, (v) an expected trajectory for moving an object, (vi) a cost for transitioning the multi-mode end effector to operate according to different modes, etc.
In some embodiments, the system determines a set of tasks to be performed (e.g., to achieve a higher-level goal such as fulfilling a set of orders) and determines an order in which the set of tasks are to be performed based on a cost function associated with performing the respective tasks within the set of tasks. The system determines the order in which the set of tasks are to be performed based on a cost associated with transitioning to control the multi-mode end effector between the first mode or the second mode. For example, the system determines the order in which the set of tasks are to be performed based at least in part on a cost associated with transitioning the second grasping mechanism (e.g., an end effector comprising a plurality of gripper arms) between the inactive state and the active state.
At 1606, a first subset of the N objects to be grasped is selected based on the order. In some embodiments, the first subset of N objects is selected according to an initial operating mode of the multi-mode end effector. For example, because the order is determined based on a cost function, the cost associated with moving items includes a cost for transitioning the multi-mode end effector between different operating modes/states. As an example, the first subset of N objects is selected to be grasped according to a same operating mode of the multi-mode end effector. For example, the first set of N objects are items to be grasped from a tray using a suction-based end effector to avoid having to change a state of the multi-mode end effector (e.g., transitioning the gripper arms between inactive and active states) during between grasping the various items in the first subset of N objects.
As another example, the first subset of N objects is selected to be grasped according to a same operating state of the multi-mode end effector. For example, the states of gripper arms of the multi-mode end effector are the same for operating in the second mode as operating in the third mode. The second mode can include using the gripper arms to grasp an item, and the third mode can include using a structure/hook on the multi-mode end effector (e.g., on a gripper arm) to push or pull an object such as a cart, stack of trays, etc. Accordingly, a subset of the N objects include an object(s) that is to be moved according to the second mode and an object(s) that is to be moved according to the third mode.
At 1608, information is obtained from one or more sensors. The information indicates whether one or more of the gripper arms is in an active state or an inactive state (or some intermediate state between the inactive state or inactive state). In some embodiments, the system uses the information corresponding to a positioning of the gripper arms in connection with controlling the gripper arms (or second grasping mechanism) to transition to the active state or inactive state according to a mode in which the multi-mode end effector is to be operated.
At 1610, a determination is made as to whether the gripper arms are positioned in a correct state. The correct state corresponds to a state in which the gripper arms are to be positioned while moving the corresponding subset set of N objects. For example, if the subset of items are to be grasped using a suction-based end effector, the correct state for the gripper arms is an inactive state (e.g., a retracted position). As another example, if the subset of objects are to be grasped using the gripper arms, the correct state for the gripper arms is an active state (e.g., a deployed position). In response to determining that the gripper arms are not in the correct state at 1610, process 1600 proceeds to 1612 at which a configuration of the gripper arms is adjusted. For example, the system controls to move (or continue to move) the gripper arms to the corrected state. Process 1600 iterates over 1608-1612 until the system determines that the gripper arms are in the correct state.
In response to determining that the gripper arms are in the correct state at 1610, process 1600 proceeds to 1614 at which the system determines to engage the object, such as an item within a tray or other source location (e.g., shelf, conveyor, etc.) in the case that the selected subset of items are to be moved using the first mode, or a tray in the case that the selected objects are to be moved using the second mode.
At 1616, the system controls to adjust a position of the multi-mode end effector. The system controls to position the multi-mode end effector to engage the object to be grasped. For example, the system moves the robotic arm and end effector to a position at which a suction-cup on the multi-mode end effector engages the object.
At 1618, the system controls the multi-end effector to grasp the object(s) with the multi-mode end effector. The system actuates a grasping mechanism to grasp the object(s). For example, if the multi-mode end effector is to be used to grasp an object using the suction-based end effector, the system actuates a suction mechanism to apply a suction force between one or more suction cups (e.g., comprised in the suction-based end effector) and the objects(s) to be grasped. For example, if the multi-mode end effector is to be used to grasp an object using the end effector having gripper arms, the system actuates a mechanism to change a position of one or more gripper arms to grasp objects(s).
At 1620, information is obtained from one or more sensors. The information indicates whether the suction-based end effector is engaged with the item(s) to be grasped, or whether the gripper arms (e.g., a thumb(s) of the gripper arms) is engaged with the tray to be grasped, etc.
At 1622, the system determines whether the object(s) is engaged. For example, the system determines whether the object(s) are securely grasped by the multi-mode end effector. In response to determining that the objects(s) is not securely grasped (e.g., a suction force between the item and the end effector is less than a threshold suction force, or that the item is not grasped by the gripper arms) at 1622, process 1600 returns to 1618 at which the system controls to grasp the object using the appropriate grasping mechanism. Process 1600 iterates over 1618-1622 until the system determines that the item(s) is securely grasped. In some embodiments, the multi-mode end effector is used to grasp a set of items at once (e.g., for simultaneous movement to respective destination locations), and iteration over 1618-1622 is used to determine whether each of the set of items to be moved are securely grasped.
In response to determining that the object(s) is securely grasped at 1622, process 1600 proceeds to 1624 at which the object(s) is moved to the destination location(s) and the grasp of the object (e.g., by the multi-mode end effector) is controlled to place the object (e.g., to release the object(s) at the destination location(s)).
For example, in the case that the multi-mode end effector is operated in the first mode, the system controls a robotic arm to move the item to the destination location (or proximity of the destination location) and then controls the suction-based end effector to release the item at the destination location. The system controls the suction-based end effector to reduce/eliminate the suction force between the suction-based end effector and the item(s).
For example, in the case that the multi-mode end effector is operated in the second mode, the system controls a robotic arm to move the object to the destination location (or proximity of the destination location) and then controls the second grasping mechanism (e.g., one or more of the gripper arms) to release the object at the destination location.
At 1626, a determination is made as to whether one or more other objects in the applicable subset of objects are to be moved. For example, the system determines whether any additional objects are to be moved while the multi-mode end effector is configured in certain state before transitioning the state of the multi-mode end effector to move another subset of objects.
In response to determining that one or more other objects in the applicable subset of objects are to be moved at 1626, process 1600 returns 1614 and process 1600 iterates over 1614-1626 until the system determines that no further objects are to be moved. Conversely, in response to determining that no further objects in the applicable subset of objects are to be moved at 1626, process 1600 proceeds to 1628.
At 1628, the system determines whether an additional subset(s) of objects are to be moved using the multi-mode end effector. For example, the system determines whether an additional subset(s) objects are to be used using a different mode of the multi-end effector. The other subset of objects are moved using multi-mode end effector in a different configuration/state of the gripper arms than the previous subset of objects.
In response to determining that additional subset(s) of objects are to be moved using the multi-mode end effector at 1628, process 1600 proceeds to 1630 at which a next subset of objects is selected, and the multi-mode end effector is controlled to change an operating mode. For example, the system controls the multi-mode end effector to transition a state of the gripper arms. Process 1600 iterates over 1608-1630 until no further subsets of the set of N objects are to be moved.
Although the foregoing embodiments have been described in connection with the grasping, moving, and placing one or more trays, various other receptacles or containers may be implemented. Examples of other receptacles or containers include bags, boxes, pallets, crates, etc.
Various examples of embodiments described herein are described in connection with flow diagrams. Although the examples may include certain steps performed in a particular order, according to various embodiments, various steps may be performed in various orders and/or various steps may be combined into a single step or in parallel.
Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive.
This application claims priority to U.S. Provisional Patent Application No. 63/253,045 entitled MULTI-MODE ROBOTIC END EFFECTOR filed Oct. 6, 2021 which is incorporated herein by reference for all purposes.
Number | Date | Country | |
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63253045 | Oct 2021 | US |