Clear coat repair is one of the last operations to be automated in the automotive and vehicle original equipment manufacturing (OEM) sector. Techniques are desired for automating this process as well as other paint applications (e.g., primer sanding, clear coat defect removal, clear coat polishing, etc.) amenable to the use of abrasives and/or robotic inspection and repair.
Prior efforts to automate the detection and repair of paint defects include the system described in U.S. Pat. Publication No. 2003/0139836, which discloses the use of electronic imaging to detect and repair paint defects on a vehicle body. The system references the vehicle imaging data against vehicle CAD data to develop three-dimensional paint defect location coordinates for each paint defect. The paint defect data (e.g., defect type, defect type, etc.) and paint defect location coordinates are used to develop a repair strategy for automated repair using a plurality of automated robots that perform a variety of tasks including sanding and polishing the paint defect.
In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.
Recent advancements in imaging technology and computational systems has made feasible the process of clear coat inspection at production speeds. In particular, stereo deflectometry has recently been shown to be capable of providing images and locations of paint and clear coat defects at appropriate resolution with spatial information (providing coordinate location information and defect classification) to allow subsequent automated spot repair.
As defect detection and classification techniques improve, the ability to automate the repair of detected defects becomes possible. The automated repair process presents new challenges, including providing materials such as abrasive articles for sanding or polishing, fluids such as water for wet sanding or polish, and removing used materials and waste from the vehicle surface. Described herein are some solutions for providing fluids to a repair area. Automated repair may benefit from fluids dispensed on or near a detected defect area. However, while paint spraying is done in large volumes, and requires longer pressurized lines running from a source to a dispenser, fluids used in defect repair are used at much lower volumes. For lower volume fluid usage, the presence of long fluid lines and dedicated machinery provides greater chance for clogs to develop as fluid sits and dries in the line. The long lines also cause waste, require solvents to clean and dedicated pumps to provide pressure to force fluid through the lines. Additionally, some polishes can thicken, clump or curdle if contact occurs with some metals. A solution is desired for low volume fluid use in automated robot repair units.
As used herein, the term “vehicle” is intended to cover a broad range of mobile structures that receive at least one coat of paint or clear coat during manufacturing. While many examples herein concern automobiles, it is expressly contemplated that methods and systems described herein are also applicable to trucks, trains, boats (with or without motors), airplanes, helicopters, motorcycles, etc.
As used herein, the term “robotic repair unit” refers to a robotic repair system that interacts with a surface to remove a defect. The robotic repair unit may be a stationary unit, that operates on a stationary surface, in some embodiments. In other embodiments, the robotic repair unit is a mobile repair unit that can move along a rail, track, or other mechanism such that it can address a defect on a moving surface. The robotic repair unit may have one or more end effectors with one or more tools, such as those described in U.S. Provisional Pat. Application with Serial No. 62/940950, filed Nov. 2, 2019 and Ser. No. 62/940960, also filed Nov. 2, 2019. However, other robotic repair unit constructions are also expressly contemplated.
Paint repair is one of the last remaining steps in the vehicle manufacturing process that is still predominantly manual. Historically this is due to two main factors, lack of sufficient automated inspection and the difficulty of automating the repair process itself.
Progress has been made on the inspection portion, and with respect to the problem of abrading a surface to address a defect in a visually acceptable manner, as described in U.S. Provisional Pat. Application 62/941286, filed Nov. 27, 2019. However, as automation progresses, additional problems have arisen, including how to provide (dispense) abrasive materials, including abrasive articles, and fluids required for the abrading process, as well as how to remove or exchange used abrasive materials from the surface.
The presence of a sufficiently capable inspection system 110 is important for identifying and addressing defects for repair by repair unit 120. The current state of the art in vehicle paint repair is to use fine abrasive and/or polish systems to manually sand/polish out the defects, with or without the aid of a power tool, while maintaining the desirable finish (e.g., matching specularity in the clear coat). An expert human executing such a repair leverages many hours of training while simultaneously utilizing their senses to monitor the progress of the repair and make changes accordingly. Such sophisticated behavior is hard to capture in a robotic solution with limited sensing.
Additionally, abrasive material removal is a pressure driven process while many industrial manipulators, in general, operate natively in the position tracking/control regime and are optimized with positional precision in mind. The result is extremely precise systems with extremely stiff error response curves (i.e., small positional displacements result in very large corrective forces) that are inherently bad at effort control (i.e., joint torque and/or Cartesian force)). Closed-loop force control approaches have been used (with limited utility) to address the latter along with more recent (and more successful) force controlled flanges that provide a soft (i.e., not stiff) displacement curve much more amenable to sensitive force/pressure-driven processing.
Some repair processes use fluids to facilitate an abrasive removal process. For example, fluid may assist in swarf removal, reduce abrasive clogging, and extend the life of the abrasive article while improving the consistency of cut during use. For example, some sanding operations are wet sanding operations, requiring water, or another fluid, to be dispersed on the repair area prior to, or during, an abrading operation. Additionally, polishing often requires polish to be dispensed before, or during, the polishing operation. Water, or another removal solvent, may also be dispensed to remove debris after the repair is completed.
Currently, fluids needed for automated robotic systems, as shown in
Additionally, different fluids are needed for different parts of the repair process. For example, wet sanding requires a water source 170. A polishing operation may use a first polish, from a first polish source 170, for a first polishing operation, followed by a second polish, requiring a second polish source 170, for a second polishing operation. This requires several fluid sources 170, each with a fluid line 180, to avoid contaminating or mixing dispensed fluids. Since many of these fluids are used at relatively low volumes for a given repair operation, this results in fluids sitting in fluid lines 180 when not in use, which can result in drying, separation, or clogging occurring. In addition to potentially providing subpar dispensed fluids, this can also result in damage to line 180 and any associated pump, dispenser, or nozzle located downstream of source 170. Currently, this risk is mitigated by running solvents through line 180, a dispenser and nozzle, and any pumping mechanisms, to ensure the fluid pathway is clear before connection to a new fluid source 170. However, this requires the use of solvents which are often not environmentally friendly, and it results in waste of polish or other fluids that are flushed out of line 180. A solution is desired that reduces the need for dedicated fluid delivery machinery and reduces the likelihood of damage to robotic repair unit 120 or associated components, while providing a consistent source of fluids needed for abrading operations.
Robotic repair unit 200 has one or more tools 240 that can interact with a worksurface. Tool 240 may include a backup pad, in one embodiment, or another suitable abrasive tool. During an abrasive operation, tool 240 may have an abrasive disc, or other suitable abrasive article, attached using adhesive, hook and loop, clip system, vacuum or other suitable attachment system. As mounted to the robotic repair unit 200, tool 240 has the ability to be positioned within the provided degrees of freedom by the robotic repair unit 200 (6 degrees of freedom in most cases) and any other degrees of freedom (e.g., a compliant force control 230 unit) with its reference frame.
Robotic repair unit 260 has several joints 260, each of which can move in x and y directions, as illustrated in
A capability is desired that reduces the distance fluid needs to travel from a fluid source to a dispensing location. Additionally, a solution is desired that results in the reduced use of harmful or environmentally unfriendly solvents. Additionally, a solution is desired that results in improved control over fluid dispensing. Embodiments provided herein provide self-contained dispensing systems that can be mounted to a robotic repair unit and easily replaced without the need for harmful solvents.
As illustrated in
In another embodiment, fluid container 280 is located on a third arm portion, such that fluid travels through line portion 281, as well as line portion 286, prior to reaching dispensing location 290. While line 281 may need to experience some flexibility, positioning fluid container in position 280 keeps a vertical travel distance for fluid to travel relatively constant.
In another embodiment, fluid container may be placed in position 275, on a second arm portion The presence of a joint between second and third arm portions may require for line portion 276 to have some flexibility, or require some built in slack to accommodate movement of robot unit 200 during repair of defects on a vehicle surface.
In another embodiment, a fluid container 270 can be located on a first arm portion, such that fluid flows through a fluid line 272 to dispensing location 290. This position may require additional pressure control to ensure that fluid can be dispensed on repair defect locations that place a dispensing location 290 lower than a fluid exit point from fluid container 270.
As illustrated in
Dispenser 310 includes a nozzle 312 which dispenses atomized fluid in the direction indicated by arrow 314. Dispenser 310 may have one or more air intake ports 316, which couple to a pressurized air supply. However, in some embodiments, dispenser 310 atomizes fluid without an air source.
Fluid container 340, in some embodiments, is compressible. As illustrated in
In block 810, a defect is detected and the defect location and characteristics identified. Subsequently, instructions related to the detected defect are received by a repair unit from a robot controller, such as application controller 150 in
Blocks 820, 830, and 840 concern the steps of repairing a detected defect. Defects may be repaired in one or more abrasive operations. For example, a defect area may first be sanded, then polished. A defect may be inspected in between the sanding and polish step and, depending on whether the defect was successfully repaired, the steps of sanding and / or polishing may be repeated.
In block 820, a fluid is dispensed onto a repair area. The fluid may be, for example, water 812 for a wet sanding or wet polishing operation. The fluid may also be, for a polishing operation, polish 814. Polish 814 may actually refer to a variety of polishes useful for different operations. Different polishes 814 may have different viscosities and different abrasive characteristics. Other fluids 816 may also be dispensed, depending on the repair operation. The fluid may be dispensed using a self-contained fluid dispensing system, such as those described in embodiments herein or any other suitable self-contained fluid dispensing system.
In block 830, the defect is abraded. Abrading a defect may include a sanding operation 822, a denibbing operation 824, a polishing operation 826, or another operation 828. Abrading the defect includes bringing a tool into contact with the defect area. Abrading may occur before, after, or simultaneously with the fluid dispensing of block 820.
In block 840, the fluid and/or waste is removed from the work surface. Removing the fluid may also include removing waste produced from the abrasive operation, including clear coat or paint “swarf”. Removing fluid may be done manually, during a human inspection operation, or may be done automatically by a tool on the repair unit or by another robotic unit altogether. Fluid removal may include a physical wiping operation 832, with an absorbent article, using a blowing operation 834, a vacuum operation 836, or another suitable operation 838.
In block 910, a fluid is dispensed by the fluid system. The fluid may be dispensed using a pump 902, which may have an associated motor 904. However, other fluid movement mechanisms are also contemplated, as indicated in block 906. For example, a fluid system may not require a pump for a fluid to dispense, if the fluid viscosity is sufficiently low, and the fluid container is placed such that gravitational forces provide sufficient pressure. Additionally, a fluid container may be coupled to a compressed air source, which may provide compressed air at a pressure sufficient to cause the fluid to flow to a dispenser.
In block 920, it is detected that a fluid container is empty, or running low. The low fluid level can be detected using a parameter-based tracking, as indicated in block 912, such as volume, time, weight, optical or a contact switch. For example, a pump or motor system may be able to volumetrically track fluid that has left a fluid source. The low fluid level can also be detected using weight sensing 914, for example in an embodiment where the fluid container is mounted on the tool side of the force control. The force control is sensitive to weight, and can accurately measure either a change in weight corresponding to almost (or all) of the fluid leaving the fluid container, or may detect that a current weight corresponds to a low fluid level. In another embodiment, the low fluid level can be detected with an optical sensor 916. For example, polish may not be optically clear. In an embodiment, such as that illustrated in
In block 930, a fluid source is replaced. A self-contained fluid dispensing system may contain a dispenser, a fluid container, a fluid liner within the fluid container, a line connecting the container to the dispenser, and a nozzle. Replacing the fluid source may include replacing some or all of these components. In order to avoid the use of potentially carcinogenic or otherwise harmful solvents, it may be preferred that the components interacting with a fluid being dispensed be replaced each time a fluid is changed. For example, a used fluid liner and a used fluid line may be replaced with a new fluid liner, filled with the fluid to be dispensed, and a new fluid liner. In some embodiments, a nozzle may also be replaceable. In embodiments where the fluid is dispensed directly from a container, the used container is replaced with a new container. The new components may come from a kit, in some embodiments and as illustrated in
Fluid replacement may require some manual intervention, as indicated in block 922. For example, when a low or empty fluid level is detected, a robotic repair unit may indicate, either visually, audibly, or through another suitable alert, that replacement is needed. A human operator may then remove the used components and replace them with new components. In another embodiment, at least some portion of the replacement is automatic, as indicated in block 924. For example, the robotic repair unit, or another robotic unit, may retrieve the used components, dispose of the used components, retrieve the new components, and / or mount the new components.
In block 940, the replaced fluid source is detected. The robotic repair unit may detect that the fluid source has been replaced, in some embodiments. Replacement may be detected, for example, by an operator manually resetting a fluid counter, as indicated in block 932. For example, in the embodiment where the self-contained fluid dispensing system includes a servo motor that can measure a volume of fluid dispensed, manual reset may include resetting a count to zero. Detecting a new fluid source unit may also include a weight sensor detecting that a tool-side weight corresponds to a full fluid container, as indicated in block 934, for embodiments where the fluid container is mounted on a portion of the robotic repair unit where weight sensing is feasible. Detecting the replaced fluid source unit may also include optical sensing, for example an optical sensor detecting that a new fluid container has been reinstalled. Other suitable sensing systems may also be feasible for other embodiments.
In block 950, the type of fluid installed on the robotic repair unit is recorded. For example, in embodiments where the new components are part of a kit, the new fluid container or liner may include a barcode / QR code or other signifier of the contents. Depending on the parameters of the fluid installed, a controller may alter a repair trajectory or force profile of an abrasive tool. In embodiments where the new components include a signifier, the fluid parameters may be automatically detected, as indicated in block 944, and communicated to a controller. However, it is also contemplated that manual recording, as indicated in block 942, may also be done. It is important to note that, with robotic repair units, a lack of knowledge or control of materials used in the process can introduce error or even failure in the repair equipment, which can result in damage to the repair equipment or the vehicle being repaired.
Components of the self-contained fluid dispensing system are designed to be disposable, in some embodiments, to reduce the need for unpleasant, harmful and environmentally caustic chemicals. In some embodiments, the only component not replaced is the dispenser itself. The replaceable components, including the liner, container, fluid line, and nozzle may all be made of a plastic material that is cheap enough to replace with each exchange of fluid components. In embodiments where the nozzle is part of the components being replaced, the replacement is essentially solvent-free.
Robotic repair unit 1000 includes a robot arm 1010. Robot arm 1010 includes one or more tools on an end effector (not shown) that are mounted to a force control 1012. Robot arm 1010 may also have an air line 1014 mounted, in embodiments where compressed air is needed to force fluid through fluid line 1028 to dispenser 1026. Robot arm 1010 may have its own movement mechanism 1016 which facilitates placement of arm components, and of tools (not shown) with respect to a surface being repaired.
Self-contained fluid dispensing system is mounted on robot arm 1010. As described above, self-contained fluid dispensing system may be mounted to any suitable arm component of a robot arm 1010. However, it may be beneficial for fluid source 1022 to be mounted on a tool side of force control 1012 to take advantage of weight sensing. Other placements are also expressly contemplated, however. Self-contained fluid dispensing system includes components intended to be disposed after a single use, to reduce the use of harmful solvents in the repair area. A fluid line 1028 transports fluid from fluid source 1022 to fluid dispenser 1026. Depending on a viscosity of the fluid being dispensed, as well as the relative placement of fluid source with respect to dispenser 1026, a pump 1024 may be necessary to facilitate fluid flow. In some embodiments, an air line 1014 is provided to fluid source 1022 to provide an additional source of pressure on fluid being dispensed to facilitate an even flow.
When fluid source 1022 is empty, or has reached a low enough level that replacement is indicated, replacement components are retrieved from replacement component source 1040. Replacement of fluid line 1028, fluid source 1022, and / or pump 1024 may occur manually, semi-automatically, or automatically.
Replacement kit 1100 may also include a connection 1116 to couple fluid container 1110 directly to a dispenser, or directly to a fluid line 1114. In some embodiments, replacement kit 1100 also includes a nozzle 1120. Connection 1116 may couple fluid container 1110 directly to nozzle 1120, such that a fluid line 1114 is not required.
In some embodiments, fluid container 1110 may be a liner that is coupled to fluid line 1114 through a separate container that does not require replacement each time that fluid needs replenishing.
A fluid dispensing system for a robotic repair unit is presented. The system includes a fluid container, a fluid dispenser associated with a robotic repair unit, a fluid coupler that connects the fluid container to the dispenser, and a mounting mechanism configured to couple the fluid container to a robotic repair unit.
The fluid dispensing system may be implemented such that the fluid dispensing system is self-contained on the robotic repair unit.
The fluid dispensing system may be implemented such that it includes a pump.
The fluid dispensing system may be implemented such that it includes a motor.
The fluid dispensing system may be implemented such that it includes an air source.
The fluid dispensing system may be implemented such that the dispenser is a pneumatic dispenser.
The fluid dispensing system may be implemented such that the fluid container and the fluid coupler are disposable.
The fluid dispensing system may be implemented such that the fluid container and the fluid coupler include plastic.
The fluid dispensing system may be implemented such that the fluid container is a liner that is disposable.
The fluid dispensing system may be implemented such that the fluid liner is a compressible liner that compresses in volume as the fluid is dispensed.
The fluid dispensing system may be implemented such that the fluid dispensing system is mounted such that gravity provides some of the pressure needed for fluid to flow from the fluid container to the fluid dispenser.
The fluid dispensing system may be implemented such that the fluid dispensing system is mounted such that gravity provides all of the pressure needed for fluid to flow from the fluid container to the fluid dispenser.
The fluid dispensing system may be implemented such that the pump is disposable.
The fluid dispensing system may be implemented such that the fluid container includes a port configured to receive a source of compressed air.
The fluid dispensing system may be implemented such that the fluid dispensing system includes a disposable nozzle that couples to the fluid dispenser.
The fluid dispensing system may be implemented such that the fluid container and the fluid coupler are single use components.
The fluid dispensing system may be implemented such that the fluid container and the fluid coupler include plastic.
The fluid dispensing system may be implemented such that the fluid container includes a signifier that identifies a fluid in the fluid container.
The fluid dispensing system may be implemented such that the fluid dispensing system is a solvent free system.
The fluid dispensing system may be implemented such that the fluid coupler includes a connector that directly connects the fluid container to the dispenser.
The fluid dispensing system may be implemented such that the fluid coupler includes a fluid line.
The fluid dispensing system may be implemented such that the fluid line is flexible.
The fluid dispensing system may be implemented such that the fluid container is configured to be mounted on a tool side of a force control.
The fluid dispensing system may be implemented such that it includes a sensor for detecting a low fluid level. The sensor may be a weight sensor, an optical sensor, or a volumetric sensor.
A method of providing a fluid for a repair operation is presented that includes positioning a dispenser in proximity to a repair area and automatically dispensing a fluid to the repair area, from the dispenser. The dispenser receives the fluid from a self-contained fluid dispensing system mounted to a robotic repair unit. The self-contained fluid dispensing system includes a fluid container coupled to the dispenser.
The method may be implemented such that the fluid container includes a disposable liner that contains the fluid.
The method may be implemented such that the fluid container includes an air port that receives compressed air.
The method may be implemented such that it also includes metering the dispensed fluid.
The method may be implemented such that the disposable liner is a bag-type liner that compresses as fluid is dispensed.
The method may be implemented such that the disposable liner is plastic.
The method may be implemented such that the fluid container is coupled to the dispenser using a coupler. The fluid container is a single use container.
The method may be implemented such that the coupler is a fluid line. The fluid line is a single-use fluid line.
The method may be implemented such that the coupler is a single-use coupler.
The method may be implemented such that the dispenser couples to a nozzle.
The method may be implemented such that the nozzle is a single-use nozzle.
The method may be implemented such that the self-contained fluid dispensing system is configured to be replaced without solvents.
The method may be implemented such that it also includes removing the fluid from the repair area.
The method may be implemented such that the repair area includes a defect.
The method may be implemented such that the defect is on a vehicle.
The method may be implemented such that the vehicle and the robotic repair unit are moving during the step of automatically dispensing the fluid to the repair area.
The method may be implemented such that automatically dispensing the fluid includes dispensing a constant stream of fluid.
The method may be implemented such that automatically dispensing the fluid includes dispensing a metered amount of fluid.
The method may be implemented such that the metered amount is controlled by a controller associated with the robotic repair unit.
The method may be implemented such that the fluid is water or polish.
A method of replacing a fluid source on a robotic repair system is presented. The method includes detecting, using a first sensor, a replacement fluid level in a used fluid source. The method also includes removing the used fluid source. The method also includes installing a new fluid source. The method also includes detecting, using a second sensor, the new fluid source.
The method may be implemented such that installing the new fluid source includes installing a new fluid source in a container mounted to the robotic repair system.
The method may be implemented such that installing the new fluid source includes connecting the new fluid source to a fluid dispenser mounted to the robotic repair system.
The method may be implemented such that the new fluid source is connected to the fluid dispenser through a fluid line.
The method may be implemented such that the fluid line is a flexible fluid line.
The method may be implemented such that the flexible fluid line and the new fluid source include a single use material.
The method may be implemented such that the fluid dispenser is mounted to the robotic repair system.
The method may be implemented such that the new fluid source is mounted on a tool side of the robotic repair system.
The method may be implemented such that the first sensor is a weight sensor that detects a weight of the used fluid source indicative of the replacement fluid level.
The method may be implemented such that the replacement fluid level is empty.
The method may be implemented such that the replacement fluid level is a low fluid level.
The method may be implemented such that first sensor or the second sensor are each selected from: a weight sensor, a volumetric sensor, or an optical sensor.
The method may be implemented such that it further includes detecting the fluid type in the new fluid source and providing the detected fluid type to a controller associated with the robotic repair unit.
The method may be implemented such that removing the used fluid source includes removing disposable components of a self-contained fluid dispensing system.
The method may be implemented such that the self-contained fluid dispensing system includes a fluid line coupling a used fluid container to the dispenser.
The method may be implemented such that the self-contained fluid dispensing system includes a pump that facilitates dispensing fluid through the fluid line.
The method may be implemented such that the used fluid container is a used fluid liner.
A robotic repair unit is presented that includes a robotic arm with a force control coupled to an end effector containing an abrasive tool and a self-contained fluid dispensing system configured to dispense a fluid on a worksurface. The self-contained fluid dispensing system includes a fluid dispenser and a fluid container coupled to the fluid dispenser. The fluid container is mounted to the robotic repair unit.
The method may be implemented such that replacement of the fluid container is solvent free.
The method may be implemented such that the fluid dispenser is a pneumatic fluid dispenser.
The method may be implemented such that the fluid container includes a fluid liner which is configured to contain fluid to be dispensed.
The method may be implemented such that the fluid container includes an air port configured to couple to a source of compressed air.
The method may be implemented such that it further includes a fluid line coupling the fluid liner to the fluid dispenser.
The method may be implemented such that the fluid liner and the fluid line are single use articles.
The method may be implemented such that it also includes a single use pump.
The method may be implemented such that replacement of the single use fluid liner and single use fluid line is solvent free.
The method may be implemented such that the dispenser includes a disposable nozzle.
The method may be implemented such that the fluid container is mounted on a tool side of a force control unit of the robotic arm.
The method may be implemented such that the force control detects a change in weight of the fluid container corresponding to a low fluid level.
The method may be implemented such that the fluid is water or polish.
The method may be implemented such that it further includes a detector configured to identify a fluid type in a fluid container.
The method may be implemented such that the detector is configured to identify the fluid type based on a signifier on the fluid container.
Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments,” or “an embodiment,” whether or not including the term “exemplary” preceding the term “embodiment,” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the certain exemplary embodiments of the present disclosure. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment,” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the certain exemplary embodiments of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.
Filing Document | Filing Date | Country | Kind |
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PCT/IB2021/051441 | 2/19/2021 | WO |
Number | Date | Country | |
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62981058 | Feb 2020 | US |