Aspects disclosed herein relate generally to robotic object grasping and manipulation.
Agricultural technology is a sector of significant commercial interest. Examples of some emerging agricultural technologies pertain to automated farming tools for crop care and irrigation. Automation of harvesting operations poses significant challenges.
In accordance with one or more embodiments, a collection tool is disclosed. A collection tool may include a body securable to a robotic arm of a collection robot, a base secured to the body, a plurality of fingers having proximal ends attached to the base, the plurality of fingers constructed and arranged to grasp a target object at distal ends of the plurality of fingers, and a blade coupled to one of the base or body and configured to cut a tether to which the target object is attached while the target object is held by the plurality of fingers.
In some embodiments, the collection tool may further comprise a guide plate having apertures through which the plurality of fingers pass. Movement of the guide plate from a position proximate the proximal ends of the plurality of fingers to a position proximate the distal ends of the plurality of fingers may cause the plurality of fingers to close around the target object. In some embodiments, a profile of curvature of the plurality of fingers acts as a cam/follower mechanism, converting linear extension of the guide plate to transverse grasping force on the target object.
In some embodiments, the collection tool may further comprise a linear actuator including a shaft coupled to the guide plate and configured to drive the guide plate back and forth along the plurality of fingers.
In some embodiments, the blade is mechanically secured to guide plate and is configured to engage and cut the tether as the guide plate reaches the proximal ends of the plurality of fingers. For example, the blade is fixedly secured to the guide plate.
In certain embodiments, the blade is disposed on a distal end of a rod passing through a bushing in the guide plate, the bushing providing for free movement of the rod through the guide plate, a spring disposed about the rod between a spring stop at a proximal end of the rod and a surface of the guide plate on a side of the guide plate opposite a side of the guide plate facing the blade. In further embodiments, the collection tool includes a counterweight coupled to the proximal end of the rod. In some embodiments, the collection tool may further comprise a latch configured to hold the rod in a retracted position in which the spring is compressed while the guide plate moves from the position proximate the proximal ends of the plurality of fingers to the position proximate the distal ends of the plurality of fingers. The latch may be further configured to release the rod and cause the blade to move, driven by the spring returning to an unexpanded state, into position to cut the tether responsive to the guide plate reaching the position proximate the distal ends of the plurality of fingers. In some embodiments, the collection tool may further comprise a hard stop on the guide plate configured to engage the rod and return the rod to the retracted position as the guide plate moves from the position proximate the distal ends of the plurality of fingers to the position proximate the proximal ends of the plurality of fingers.
In some embodiments, the blade is secured to a distal end of a shear bar having a proximal end fixedly secured to the body. In some embodiments, the base is configured to rotate to bring the tether of the target object, while the target object is held by the plurality of fingers, into contact with the blade and to apply sufficient rotational force to the target object that the blade cuts the tether. In some embodiments, the shear bar has a bifurcated profile. In some embodiments, the shear bar includes a fixed beam, a bifurcated head, and a pivot coupling the bifurcated head to the fixed beam. In some embodiments, the shear bar includes a hooked distal end.
In further embodiments, the collection tool includes a bar having a proximal end fixedly secured to the body and a distal end configured to move and/or stabilize a position of the tether. In some embodiments, the distal end of the bar includes a resilient material. In some embodiments, the blade is fixedly secured to the body.
In certain embodiments, a grasping assembly including the base and plurality of fingers is configured to move away from the body, capture the target object in the plurality of fingers while the base is disposed away from the body, and to retract back to the body with the target object secured in the plurality of fingers, retracting of the grasping assembly back to the body causing the tether to come into contact with and be cut by the blade.
In some embodiments, the blade is rotationally secured to the body. The collection tool may further include an actuator configured to cause the blade to rotate relative to the body and come into contact and cut the tether while the target object is secured in the plurality of fingers. In some embodiments, the plurality of fingers is arranged in an elongated rectangular configuration. In some embodiments, the plurality of fingers is arranged in an asymmetric cross pattern.
In further embodiments, the collection tool may include a vision system configured to: capture an image of the target object, calculate a size of the target object from the image, an determine if the target is ready for collection by comparing the calculated size to a threshold size. In some embodiments, the size is a length of the target object. In some embodiments, the size is a circumference of the target object. In certain embodiments, the vision system may be further configured to determine a location at which the tether should be cut based on an analysis of the image.
In accordance with one or more aspects, a method of collecting a target object utilizing the collection tool as described herein is disclosed. The method may comprise enveloping the target object with the plurality of fingers on the collection tool, grasping the target object with the plurality of fingers on the collection tool, cutting the tether of the target object, and removing the target object from a surrounding environment.
In some embodiments, the method may further comprise identifying and/or locating the target object. In some embodiments, the method may further comprise assessing ripeness of the target object. Ripeness may be assessed by a size of the target object. In some embodiments, the size is a length of the target object. In some embodiments, the size is a circumference of the target object. The size of the target object may be measured using a vision system comprising a camera. In some embodiments, the measured size is compared to a predetermined threshold size. In certain embodiments, an identified location and the measured size of the target object is used to determine a location for cutting the tether of the target object. In some embodiments, environmental obstructions are substantially avoided. In some embodiments, grasping of the target object is performed independently of cutting of the tether of the grasped target object. In further embodiments, the method may comprise releasing and/or delivering the target object to a downstream process.
In accordance with one or more aspects, a collection system is disclosed. The collection system may include a robotic arm and the collection tool as described herein operatively attached to the robotic arm.
In some embodiments, the collection system may further comprise a controller programmable to operate the robotic arm and/or the collection tool. In some embodiments, the collection system may further comprise a vision system programmable to identify and/or locate a target object by capturing an image of the target object. In some embodiments, the vision system may be further configured to calculate a size of the target object from the image. The vision system may be further configured to determine if the target is ready for collection by comparing the calculated size to a threshold size. In some embodiments, the size is a length of the target object. In some embodiments, the size is a circumference of the target object. The vision system may be further configured to determine a location at which the tether should be cut based on an analysis of the image. In further embodiments, the robotic arm may be configured to release and/or deliver the target object to a downstream process.
These and other capabilities of the disclosed subject matter will be more fully understood after a review of the following figures, detailed description, and claims. It is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:
Many types of agricultural produce will not release from the vine when only grasped and pulled or twisted. These produce items are typically manually harvested with hand shears, so that workers can reduce disruption to the vines while harvesting. Mechanical and robotic harvesting systems that work on these types of crop may be equipped to mechanically shear the vine connecting the fruit to the main trunk of the vine. By employing a mechanism dedicated to shearing the vine or shearing the vine in concert with other robotic manipulator motions, a robotic harvesting system can achieve higher throughputs and picking coverages by cleanly shearing the vine at the site of the produce growth. A dedicated shearing, i.e., cutting, element ensures that the motion imparted to the vine due to harvesting will result in the least possible vine sway, which in turn reduces the time until the next pick can be attempted, thus boosting possible harvesting throughput. In addition, clean vine severance is desired because anywhere a vine has been cut is an open wound—vine tears rarely heal as completely or as quickly as clean sheared cuts. By reducing vine swinging and creating clean, healable cuts, increased throughput and yield for a robotically harvested crop may be achieved.
In accordance with one or more embodiments, a target object may be strategically grasped and manipulated, for example, to facilitate collection, e.g., harvesting, thereof. In some embodiments, a target object may be picked in place, i.e., from a target surface or a target location. In at least some embodiments, the target object may be grasped, and a portion thereof, such as a tether, cut or sheared so as to remove the target object in place. In various embodiments, a grasped and/or dislodged target object may be removed from an environment, i.e., an agricultural environment. In at least some embodiments, a tool may be configured to independently grasp and shear a portion of the target object.
In accordance with one or more embodiments, a wide variety of target objects may serve as an intended workpiece. Target objects may vary in terms of their size, geometry, firmness, and various other properties. In some embodiments, the target object may generally be characterized as delicate or otherwise easily crushable. In at least some embodiments, the target object may pertain to agricultural produce, e.g., the target object may be agricultural produce, i.e., a fruit or a vegetable. In some specific non-limiting embodiments, the target object may be a strawberry or an elongate vegetable, such as a cucumber, eggplant, pepper, or gourd, e.g., a yellow squash. For example,
In accordance with one or more embodiments, a target object may be present in a variety of environments or settings. In some embodiments, the target object may be in an agricultural environment. In other embodiments, the target object may be in an industrial environment. The environment or setting of the target object may be indoors or outdoors. In some embodiments, the target object may generally be loose in the target environment. In other embodiments, the target object may be attached or tethered such as to a host in the target environment. For example, a target object may pertain to agricultural produce on a plant, e.g., a vine or stem, for ripening.
In accordance one or more embodiments, a collection tool may be used to perform one or more of the following functions with respect to a target object: grasping, dislodgment, and/or removal. A target object may be enveloped and grasped. Alternatively, a target object may be partially enveloped when grasped. In some embodiments, a grasped target object may generally be dislodged via shearing or cutting portion of the target object from where it is tethered. For example, a target object may be a strawberry or a cucumber on a vine as shown in
In accordance with one or more embodiments, a collection tool may generally include a body securable to a robotic arm of a collection robot. A base having a plurality of fingers having proximal ends attached to the base may be secured to the body. The plurality of fingers may be constructed and arranged to envelop a target object at distal ends of the plurality of fingers. The collection tool may further include a blade coupled, directly or indirectly, to the base or body and configured to cut or shear a tether to which the target object is attached while the target object is held by the plurality of fingers. In some embodiments, the base may be configured to rotate relative to a first position. For example, the base may be configured to rotate up to 90° from a first position. The collection tool may be interchangeable so as to accommodate target objects of varying sizes and/or requirements. An example of a collection tool having a base, a plurality of fingers, and a blade is shown in
In accordance with one or more embodiments, a collection tool may include a guide plate having apertures through which the plurality of fingers pass. The guide plate, when moved from a position proximate the proximal ends of the plurality of fingers to a position proximate the distal ends of the plurality of fingers, causes the plurality of fingers to close around the target object. The guide plate may be actuated, i.e., back and forth, along the plurality of fingers by the actuation of a linear actuator. The shaft of the linear actuator may be coupled to the guide plate by any suitable connection, such as a mechanical fastener or chemical fastener, such as illustrates in
In accordance with one or more embodiments, the plurality of fingers may have a curved profile. The curvature of the plurality of fingers may be configured to act as a cam/follower mechanism. In this configuration, when the guide plate is actuated along the plurality of fingers, the linear motion is converted into a transverse motion at the distal ends of the plurality of fingers, causing the plurality of fingers to close around a portion of the target object. In some embodiments, the plurality of fingers may be jointed to facilitate grasping of the target object. In other embodiments, the plurality of fingers may be contoured to facilitate grasping of the target object. In at least some embodiments, the plurality of fingers may include a conformable feature and/or an engagement surface to facilitate grasping of the target object. As illustrated in
In accordance with one or more embodiments, the blade of the collection tool may be mechanically secured to guide plate. As the guide plate is actuated linearly along the length of the plurality of fingers by the linear actuator, the blade may be configured to engage and cut the tether of the target object, such as a vine or stem, as the guide plate approaches or reaches the proximal ends of the plurality of fingers. In some embodiments, the blade may be fixedly secured to the guide plate using any suitable mechanical fastener, such as a nut and bolt or similar. In this configuration, the position of the blade relative to the guide plate may be adjusted such that the blade can engage the tether of the target object; a skilled artisan can appreciate that the position of the blade relative to the guide plate may be different for target objects of varying dimension. An example of a blade 340 fixedly secured to the guide plate 330 is illustrated in
In accordance with one or more embodiments, the blade of the collection tool may be disposed on a distal end of a rod passing through a bushing in the guide plate. A schematic of this embodiment is illustrated in
In accordance with one or more embodiments, the collection tool may include a shear bar that may be configured to shear or cut the tether of the target object when engaged by the plurality of fingers. The shear bar may have a blade or similar structure secured at its distal end; such embodiments are illustrated in
In some embodiments, the cross-sectional shape, i.e., the engagement surface, of the distal end of the shear bar may be adapted to be suited to shear or cut tethers of varying dimensions, properties, and locations.
In accordance with one or more embodiments, the proximal end of the shear bar may be fixedly secured to the body of the tool. In this configuration, the base of the tool is configured to rotate after grasping the target object with the plurality of fingers such that the tether of the target is brought into contact with the distal end of the shear bar. The rotation of the base of the tool having a fixed shear bar is illustrated in
In accordance with one or more embodiments, a collection tool may include an actuator, separate from the actuator of the body that closes the plurality of fingers, that is connected to the shear bar and configured to directly actuate the shear bar to shear or cut the tether of the target object. This embodiment is illustrated in
In accordance with one or more embodiments, a collection tool may include a blade fixedly secured to the body of the tool and a translatable grasping assembly.
In accordance with one or more embodiments, a collection system may be programmed to operate a robotic arm and/or collection tool according to customizable routines. For example, in some non-limiting embodiments, a collection system may sequentially envelop, grasp, detach, and remove a target object from an environment.
In some embodiments, a robotic collection system may include at least one sensor associated with a collection tool, robotic arm, and/or other component. In some embodiments, the robotic arm may be further configured to release and/or deliver the target object to a downstream process. In accordance with one or more embodiments, a robotic manipulator may allow for customized motion, travel, and/or force profiles during actuation of a related robotic arm and/or collection tool. In at least some embodiments, a robotic manipulator may be calibrated.
In accordance with one or more embodiments, a target object may be identified, located, and/or characterized. For example, a target object may be identified by ripeness. Ripeness of many target objects, such as fruits and vegetables, may be assessed by their color. For example, tomatoes, strawberries and peppers may exhibit a color change as they ripen. In some examples, ripening is not indicated by color changes. For those target objects that do not change colors when they ripen, such as cucumbers, a vision system, illustrated as 1102 in
Once the size or characteristic dimension is known for a target object, this value may be used to automatically infer a location where the tether of the target object may be sheared or cut. Since the location of the blade or other cutting element is at a height relative to the center axis of the collection tool, which is known a priori, a constant height offset may be added to half the length, 1, to generate a location where the collection tool's cutting element should be deployed to cut the tether of the target object; this is illustrated as h in
In accordance with one or more embodiments, a collection tool as described herein may be utilized in a method of collecting a target object. The target object may be grasped with the plurality of fingers. The grasped target object may be brought towards a blade or shear bar to cut or shear a tether securing the target object. A blade or a shear bar may be brought towards the grasped target object to cut or shear a tether securing the target object. Grasping of the target object may be performed independently of cutting or shearing the tether of the grasped target object. The grasped target object may then be removed and/or released from the environment. For example, the target object may be released and/or delivered to a downstream process. The target objected may be enveloped, grasped, dislodged, and removed in series in some non-limiting embodiments. Environmental obstructions, i.e., other target objects, vines, and/or leaves, may be substantially avoided during the collection operation.
Having thus described several aspects of at least one implementation, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure and are intended to be within the spirit and scope of the disclosure. The acts of methods disclosed herein may be performed in alternate orders than illustrated, and one or more acts may be omitted, substituted, or added. One or more features of any one example disclosed herein may be combined with or substituted for one or more features of any other example disclosed. Accordingly, the foregoing description and drawings are by way of example only.
The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. As used herein, the term “plurality” refers to two or more items or components. As used herein, dimensions which are described as being “substantially similar” should be considered to be within about 25% of one another. The terms “comprising,” “including,” “carrying,” “having,” “containing,” and “involving,” whether in the written description or the claims and the like, are open-ended terms, i.e., to mean “including but not limited to.” Thus, the use of such terms is meant to encompass the items listed thereafter, and equivalents thereof, as well as additional items. Only the transitional phrases “consisting of” and “consisting essentially of,” are closed or semi-closed transitional phrases, respectively, with respect to the claims. Use of ordinal terms such as “first,” “second,” “third,” and the like in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/020476 | 3/2/2021 | WO |
Number | Date | Country | |
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62984125 | Mar 2020 | US |