Pixelated electrostatic adhesion

Abstract

To provide a system for moving objects that is capable of selectively grasping and moving the objects without damaging the objects or grasping unwanted nearby objects.SOLUTION: Control for pixelated electrostatic adhesion can be provided by: a voltage converter configured to increase an input voltage to an output voltage; a first gripping circuit, configured to selectively provide the output voltage at a first polarity to a first subset of electrodes of a plurality of electrodes; a second gripping circuit, configured to selectively provide the output voltage at a second polarity opposite to the first polarity to a second subset of electrodes of the plurality of electrodes that are associated with and different from the first subset of electrodes; a first release circuit, configured to selectively reverse the output voltage provided to the first subset of electrodes to the second polarity; and a second release circuit, configured to selectively reverse the output voltage provided to the second subset of electrodes to the first polarity.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] Aspects of the present disclosure relate to control logic and control circuits for electrostatic gripper devices. The control methods described herein may result in one or more of improved grip strength, rapidity in releasing objects from the gripper device, and variability in grip force for different objects compared to other control methods. [Background technology]

[0002]

[0002] The movement of objects, such as parts and materials, is an important aspect of manufacturing and assembly. Conventional systems are limited when it comes to moving objects. Challenges exist, particularly when using conventional systems to move thin or fragile materials. Following this example, materials can be moved manually or automatically. Manual operations are cumbersome and can damage the material. Automatic operations include robotic systems with suction or electrostatic end effectors. Suction-based systems require suction to be maintained for each area of ​​the material that the end effector contacts. The suction that can be maintained is limited by the power output of the suction source, such as a suction pump. Suction sources are very loud and require a large amount of energy to generate each required suction. Furthermore, suction-based systems are not suitable for fragile materials because they can damage the material by applying a force greater than the material can withstand.

[0003]

[0003] Therefore, there is a need for an improved system for object movement that can selectively grasp and move objects without damaging the object or grasping unwanted objects nearby. Summary of the Invention

[0004]

[0004] Some aspects provide a control unit comprising: a voltage converter configured to boost an input voltage relative to an output voltage; a first gripping circuit configured to selectively supply an output voltage in a first polarity to a first electrode subset of a plurality of electrodes; a second gripping circuit configured to selectively supply an output voltage in a second polarity opposite to the first polarity to a second electrode subset of the plurality of electrodes different from the first electrode subset, associated with the first electrode subset; a first release circuit configured to selectively invert the output voltage supplied to the first electrode subset to the second polarity; and a second release circuit configured to selectively invert the output voltage supplied to the second electrode subset to the first polarity.

[0005] Some aspects provide an apparatus including a gripper device configured to electrostatically grip an object via a plurality of electrodes and a logic controller configured to instruct the gripper device to grip the object, wherein the gripper device is instructed to grip the object by selecting individual electrodes of the plurality of electrodes to grip the object, actuating a first subset of the individual electrodes to deliver a voltage at a first duty cycle and actuating a second subset of the individual electrodes to deliver a voltage at a second duty cycle different from the first duty cycle, and to release the object from the gripper device by energizing the first subset of the individual electrodes according to a third duty cycle different from the first duty cycle and energizing the second subset of the individual electrodes according to a fourth duty cycle different from the second duty cycle.

[0006]

[0006] Some aspects provide a method that includes, in response to receiving a first command to grip an object via a gripper device having a plurality of electrodes, identifying at least two electrodes of a plurality of electrodes associated with the object, activating the at least two identified electrodes to a first subset of the at least two electrodes to transmit a voltage with a first polarity and to a second subset of the at least two electrodes to transmit a voltage with a second polarity opposite to the first polarity, and in response to receiving a second command to release the object from the gripper device, reversing the polarity of the voltage of the first subset and the second subset.

[0007] The following description and the annexed drawings set forth in detail certain illustrative features of the one or more embodiments.

[0008]

[0008] The accompanying drawings illustrate certain aspects of one or more embodiments and therefore should not be considered limiting of the scope of the disclosure. [Brief explanation of the drawings]

[0009] [Figure 1] 1 illustrates a gripper device deployed in a manufacturing environment, according to aspects of the present disclosure. [Figure 2] 1 shows a pixelated electroadhesive system for grasping an object according to aspects of the present disclosure. [Figure 3A] FIG. 2 shows a portion of a top view of the pixelated electroadhesive system of FIG. 1 in accordance with an embodiment of the present disclosure. [Figure 3B] FIG. 3 shows a cross-sectional side view of the pixelated electroadhesive system of FIG. 2 in accordance with an embodiment of the present disclosure. [Figure 4] 14A shows the wiring layout for the backside of a pixelated electroadhesive system for gripping an object in accordance with aspects of the present disclosure. [Figure 5A] 10A-10C illustrate different pixelated electroadhesive systems for gripping objects according to aspects of the present disclosure. [Figure 5B]10A-10C illustrate different pixelated electroadhesive systems for gripping objects according to aspects of the present disclosure. [Figure 5C] 10A-10C illustrate different pixelated electroadhesive systems for gripping objects according to aspects of the present disclosure. [Figure 6A] 10A-10C illustrate subsets of electrode pixels configured to grip different objects, according to aspects of the present disclosure. [Figure 6B] 10A-10C illustrate subsets of electrode pixels configured to grip different objects, according to aspects of the present disclosure. [Figure 7] FIG. 1 is a block diagram of a control architecture for a gripper device according to aspects of the present disclosure. [Figure 8A] 1 illustrates an exemplary voltage driver circuit according to an aspect of the present disclosure. [Figure 8B] 1 illustrates an exemplary voltage driver circuit according to an aspect of the present disclosure. [Figure 8C] 1 illustrates an exemplary voltage driver circuit according to an aspect of the present disclosure. [Figure 9A] 1 illustrates a power control architecture for a tile structure having a high voltage generator, according to an aspect of the present disclosure. [Figure 9B] 1 illustrates a power control architecture for a tile structure having a high voltage generator, according to an aspect of the present disclosure. [Figure 10] 1 illustrates a switching unit according to an aspect of the present disclosure. [Figure 11] 1 illustrates a control unit according to an aspect of the present disclosure. [Figure 12A] 1 illustrates a layout of a heating element for use with a gripper device, according to an aspect of the present disclosure. [Figure 12B] 1 illustrates a layout of a heating element for use with a gripper device, according to an aspect of the present disclosure. [Figure 13] FIG. 1 is a flow diagram of a method for controlling a gripper device according to an aspect of the present disclosure. [Figure 14] FIG. 10 is a flow diagram of a control method for actuating electrodes of a gripper device when gripping an object, according to an aspect of the present disclosure. [Figure 15] 1 is a flow diagram of a method for controlling a switching unit according to an aspect of the present disclosure. [Figure 16] 1 illustrates a computing device according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010]

[0026] For ease of understanding, wherever possible, the same reference numerals have been used to designate identical elements common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0011]

[0027] Aspects of the present disclosure provide an apparatus, method, processing system, and computer-readable medium for controlling an electrostatic gripper device. A controller identifies individually selectable and controllable electrodes of the gripper device to match the shape and position of an item to be lifted by the gripper device. The controller supplies voltages of alternating polarity to these identified electrodes to electrostatically grasp an object, move it to a desired location, and then release it, thereby controlling the device to selectively grasp and move an object, such as a material or part, without damaging the object or gripping unwanted nearby objects.

[0012]

[0028] Typically, objects may be moved using manual or automated operations. For example, lifting and placing materials, such as dry carbon fiber plies, may be performed manually. One or more operators carefully lift the dry carbon fiber plies from the ply cutter if the plies are large. The plies may be removed from within the scrap material "skeleton." One or more operators then transport the plies to a different location, such as the next tool or a storage area. However, manual operations are slow, require personnel, and can damage the plies if they are not handled carefully.

[0013]

[0029] Automated operations can also be used to lift and place carbon fiber plies. For example, the end effector may be used in conjunction with a robotic system, such as a gantry or arm. The end effector may include a suction system with separate suction cups in a grid or optimized position layout to complement the known ply shape being lifted. The robotic system positions the end effector above the ply, activates the suction cups, and lifts and moves the ply. While suction systems work well for stiff materials such as dry twills, multiaxials, and prepregs, they can damage more delicate or less stiff materials, such as dry non-crimp fabric (NCF) unidirectional materials. For example, suction systems can damage unidirectional NCF, such as dry carbon fiber plies. Delicate materials require several suction cups positioned to complement the ply boundaries and avoid breaking or damaging the ply edges. Suction-based systems have several other drawbacks. The systems are heavy, require a lot of energy to generate the required suction, are difficult to miniaturize to allow for individual control of small areas, and can suck up fibers that block ports in the system, but are noisy and require the suction exhaust to be filtered in a room within a Contamination Control Area (CCA).

[0014]

[0030] Another example of an automated process uses an end effector that includes an electrostatic system that uses electroadhesion to lift and place plies. Electrostatic-based systems require high voltage and use a pad and electrostatic energy to "grab" the material. Electrostatic systems include electrodes as part of the pad to generate an electrostatic field using alternating open circuits of positive and negative electrode pairs. The electrode pairs are embedded in a dielectric medium or pad material and connected to a high-voltage power supply. Traditional electrostatic systems use an interdigitated electrode layout as part of the pad, with the positive and negative electrodes interdigitated. The power supply creates an electrostatic field through the opposing positive and negative charges of the electrode pairs. When the pad is placed near the ply, the electrostatic field temporarily polarizes corresponding regions of the ply at the atomic level, generating an electrostatic force between the ply and the electrode pair. For example, when the pad is placed near the ply, the charges in various regions of the ply are rearranged (i.e., polarized) so that the positive charges on the ply are attracted to the negative electrode and the negative charges on the ply are attracted to the positive electrode.

[0015]

[0031] Electrostatic systems offer several advantages. For example, they are nearly silent, constructed from semiconductors, require significantly less power than suction-based systems, and do not require air filtration. Electroadhesion can be used with conductive and non-conductive materials. Electrostatic systems can also be manufactured using standard printed circuit board (PCB) methods, making them more cost-effective and beneficial compared to manual or suction-based systems. However, conventional electrostatic designs have drawbacks. For example, conventional systems require the entire pad to be used to lift the ply because the pad does not have separate electrode zones that can be individually powered on and off to control adhesion. Using the entire pad is problematic when only a portion of the ply must be lifted. For example, a ply cutter may cut a portion of the ply from a ply sheet. Following this example, the cut portion of the ply must be lifted while leaving the scrap material skeleton of the ply sheet. However, conventional systems that use the entire pad to lift the ply cannot be used to lift the ply cutout and leave behind a remnant portion if the pad is larger than the ply cutout and extends beyond its boundary or perimeter. Furthermore, conventional systems cannot use multiple pads to create separate zones because the size of conventional pads can result in large "dead zones" when one pad of the multiple pads is not energized. Large dead zones would limit the ability to lift an object.

[0016]

[0032] Conventional electrostatic systems have additional disadvantages. For example, conventional systems require significant voltage levels (e.g., 2,000-4,000 volts (V)) to generate electroadhesion sufficient to lift the ply. Conventional electrostatic systems grip any material that contacts the pad or comes within a set distance of the pad (collectively, "contacting the pad"). Therefore, conventional electrostatic-based systems cannot selectively grip only objects that contact the pad without gripping other objects that also contact the pad. Additionally, the comb-like layout can cause the ply to slip as the robotic system moves, which can undesirably damage the ply or cause the ply to slip off the electrode pad.

[0017]

[0033] The improved pixelated electroadhesive systems and control methods described herein address this issue by using separate zones of selectively powerable or energizable electrodes, which may be variously referred to as electrode pixels, gripping pixels, "grip cells," or gripping electrodes.

[0018]

[0034] As used herein, unless otherwise specified, the terms "grip" and "grasp" refer to the controlled electrostatic adhesion (e.g., electrostatic grip / grasp) of an object to a gripping surface controlled to generate an electric field. When an opposite charge is applied by an adjacent electrode of the gripper device, the electric field can affect the charge on the surface of the object and electrically attract the object to the electrode (and, optionally, an intervening surface between the electrode and the object).

[0019]

[0035] As used herein, the term "release," unless otherwise specified, refers to the controlled cessation of electrostatic adhesion of an object (e.g., to selectively cease gripping of the object). Releasing an object may variously include one or more of removing the electric field generated by the electrodes, reversing the electric field generated by the electrodes, amplifying the reversed electric field generated by the electrodes, and activating a (secondary) mechanism that physically pushes the object away from the gripping surface.

[0020]

[0036] In various aspects, the electrodes (and optional intervening surfaces) may be rigidly positioned on a pad to grip one side of an object, while in other aspects, the electrodes (and optional intervening surfaces) may be flexibly or rotatably positioned on one or more pads to grip a configurable number of sides (or curved surfaces). The size, shape, layout, and stiffness / flexibility of a given gripper device will generally be adapted to the environment in which the gripper device will be deployed and the type of object it will grasp via electroadhesion, all of which can benefit from the present disclosure. Accordingly, the devices, methods, processing systems, and computer-readable media described in this disclosure may be applied to a variety of gripper devices adapted to different types of objects.

[0021]

[0037] In some embodiments, when gripping an object, the controller sets a first subset of electrodes to a fixed first polarity and a second subset of electrodes to a fixed second polarity. In such embodiments, when releasing the object, the controller reverses the polarity of the previously activated electrodes, causing the object to fall quickly and preventing the material from becoming charged. In other embodiments, when gripping an object, the controller sets the first subset of electrodes to alternating first and second polarities and the second subset of electrodes to alternating second and first polarities (opposite to the first subset) to prevent the accumulation of residual charge in the object. In such embodiments, when releasing the object, the controller sets the voltage of each previously activated electrode to ground voltage, causing the object to fall quickly and preventing residual charge from remaining within.

[0022]

[0038] As part of the control logic, optical sensors can be used to verify that an object has been gripped or released by the gripper device. A solenoid or blower release mechanism can be used to push the object away from the gripping surface. Additionally, a load resistor on the gripping surface can be controlled to heat the gripping surface to a desired temperature when actuated to grip an object.

[0023] Example Operating Environment

[0039] 1 illustrates a gripper device 110 deployed in a manufacturing environment 100 in accordance with an aspect of the present disclosure. The gripper device 110 is deployed to move objects between a pickup area 120 and a drop-off area 130. In various aspects, the environment 100 may include one or more pickup areas 120 and one or more drop-off areas 130 for a given gripper device 110, and multiple gripper devices 110 may be deployed to share one or more pickup areas 120 or drop-off areas 130. Various other devices may share the manufacturing environment 100 with the gripper device 110 and may be deployed to access one or more pickup areas 120 and drop-off areas 130.

[0024]

[0040] Gripper device 110 is a gripping device provided to move various objects 140a-140d (generally or collectively, objects 140) from pickup area 120 to designated locations 150a-150b (generally or collectively, designated locations 150) within drop-off area 130. Gripper device 110 includes a gripping surface (arranged according to one or more geometries, described in more detail with respect to FIGS. 2-6B ) that is selectively controllable to grasp and release different objects 140 within environment 100. Gripper device 110 can move within environment 100 with up to six degrees of freedom (e.g., positive and negative translation along X, Y, and Z axes, yaw, pitch, and roll rotation about X, Y, and Z axes) according to various articulation systems and can move grasped objects 140 accordingly (e.g., translate and rotate object 140 from an initial position and orientation to a final position and orientation).

[0025]

[0041] As shown, a first object 140a and a second object 140b are shown within the pickup area 120 and have corresponding designated locations 150a, 150b within the drop-off area 130, and a signal is sent to the gripper apparatus 110 to move each object 140. In contrast, an intervening third object 140c is disposed within the pickup area 120 but does not have a corresponding designated location 150 within the drop-off area 130, and therefore remains within the pickup area 120 (at least until the first object 140a and the second object 140b are moved to the drop-off area 130). In some aspects, the pickup area 120 and the drop-off area 130 are electrically grounded (or controllable to be electrically grounded) to reduce electrostatic buildup within the objects 140.

[0026]

[0042] In various embodiments, the designated locations 150 for drop-off within the drop-off area 130 may vary the relative positions of two or more objects 140 selected from the pickup area 120 in the same pickup operation. Additionally, in some embodiments, the designated locations 150 may overlap each other or an object 140 previously placed within the drop-off area 130 (e.g., the fourth object 140d) to allow the gripper device 110 to stack various objects 140 placed within the drop-off area 130.

[0027]

[0043] The gripping surface of gripper device 110 provides pixel-by-pixel control of which portions of the gripping surface are activated (i.e., gripping object 140) or deactivated (i.e., releasing object 140) at any given time. Thus, at a first time, gripper device 110 may grasp first object 140a and second object 140b (and avoid grasping third object 140c), move objects 140a, 140b to drop-off area 130, orient first object 140a to first designated location 150a, release first object 140a, orient second object 140b to second designated location 150b, and release second object 140b at a third time. Similarly, the gripper device 110 may, at a first time, orient and move to grasp a first object 140a (and avoid grasping a second object 140b or a third object 140c), and grasp a second object 140b (and avoid dropping the first object 140a or grasping the third object 140c) within the pickup area 120, and, at a third time, move to the drop-off area 130 and orient the first object 140a and the second object 140b to corresponding designated locations 150a, 150b to release the first object 140a and the second object 140b. Thus, the gripper device 110 can change the relative orientation of two or more objects 140 with respect to one another between the pickup area 120 and the drop-off area 130 without moving between the pickup area 120 and the drop-off area 130 multiple times. In other words, by controlling which portions of the gripping surface are activated or deactivated at any given time, small movements of the relative position of the gripper device 110 in one or more of the pickup area 120 and drop-off area 130 can reduce the amount of large movements required between the pickup area 120 and drop-off area 130, thereby saving time and energy during the manufacturing process and reducing the risk of damaging parts during manufacturing operations.

[0028]

[0044] In addition to or instead of moving gripper device 110 relative to pickup area 120 and drop-off area 130, pickup area 120 and drop-off area 130 may move relative to gripper device 110 (e.g., via a conveyor belt) to allow gripper device 110 to select different objects 140 from pickup area 120 and move them to drop-off area 130. Those skilled in the art will be familiar with various automated systems that can be used in environment 100 to move one or more of gripper device 110, pickup area 120, and drop-off area 130 relative to one another, and a description of such elements has generally been omitted from this disclosure so as not to detract from the pixelated electroadhesion control of gripper device 110 described herein.

[0029]

[0045] By increasing the fine control for selecting various objects by the gripper device 110, the present disclosure may have advantages such as improving assembly speed, reducing power consumption of the gripper device 110, and reducing wear on the articulation system.

[0030] An exemplary pixelated electroadhesive system for grasping an object

[0046] FIG. 2 shows a pixelated electroadhesive system 200 for grasping an object, according to an embodiment of the present disclosure.

[0031]

[0047] A pixelated electroadhesive system 200 (referred to as system 200) includes a device such as a pixelated pad 202 for gripping an object. The pixelated pad 202 is configured to electrostatically grip an object using a substrate 210. The substrate 210 comprises a plurality of electrode pixels 212. In the embodiment shown, the plurality of electrode pixels 212 includes a plurality of negative electrode pixels 214 (one of which is labeled) and a plurality of positive electrode pixels 216 (two of which are labeled). In this example, each electrode pixel in the plurality of electrode pixels 212 is adjacent to at least two other electrode pixels in the plurality of electrode pixels 212. The at least two other electrode pixels have the opposite polarity as the respective electrode pixel. For example, a negative electrode pixel 214 is adjacent to at least two positive electrode pixels 216. Thus, the plurality of electrode pixels 212 are arranged in a grid pattern or a checkerboard pattern in which the polarity of adjacent electrode pixels alternates. The grid pattern of the plurality of electrode pixels 212 advantageously allows the system 200 to selectively power or energize separate zones or subsets of the electrode pixels 214 and 216, as described in connection with Figures 6A and 6B.

[0032]

[0048] The electrode pixels 214 and 216 shown in FIG. 2 are merely one example of how each of the plurality of electrode pixels 212 may be configured. In some embodiments, the plurality of electrode pixels 212 may be configured differently such that each pixel of the plurality of electrode pixels 212 may be set to a different polarity than that shown in FIG. 2. For example, the polarity of the electrode pixels 212 may be configured to be reversed from that shown in FIG. 2, such that an electrode pixel shown as a negative electrode pixel 214 may instead be a positive electrode pixel 216, and an electrode pixel 212 shown as a positive electrode pixel 216 may instead be a negative electrode pixel 214. In some embodiments, the plurality of electrode pixels 212 may be configured to include only negative electrode pixels or only positive electrode pixels. In some embodiments, such as those described in connection with FIG. 5A, the plurality of electrode pixels 212 may be configured such that the electrode pixels 214 and 216 are arranged in different patterns (e.g., patterns other than a checkerboard). In some aspects, the plurality of electrode pixels 212 may be configurable such that each pixel of the plurality of electrode pixels 212 can be set to a positive or negative polarity, or to a grounded (e.g., unpowered or unenergized) state. For example, the polarity of the electrode pixels 212 may be set to a negative electrode pixel 214 and a positive electrode pixel 216 as shown in FIG. 2 to grasp or lift an object with the pixelated pad 202. When the object is released, the polarity of the plurality of electrode pixels 212 may be reversed to move the object away from the pixelated pad 202. Thus, the description of the system 200 in FIG. 2 is not intended to limit the arrangement or configuration of the plurality of electrode pixels 212 to the arrangement in FIG. 2.

[0033]

[0049] As shown, the plurality of electrode pixels 212 includes a rectangular perimeter 230. In some embodiments, the perimeter 230 may be a different shape, such as a circle, semicircle, triangle, square, arc, bow, or other polygon, as described in connection with FIGS. 5B and 5C . Each electrode pixel (referred to as electrode pixels 214 and 216) of the plurality of electrode pixels 212 is separated from any adjacent electrode pixel of the plurality of electrode pixels 212 by a gap 218. For example, the gap 218 separates a negative electrode pixel 214 located at a corner of the pixelated pad 202 from two adjacent positive electrode pixels 216. Following this example, the negative electrode pixel 214 located at the center of the pixelated pad is adjacent to four positive electrode pixels 216. The gap 218 separates the negative electrode pixel 214 from the adjacent positive electrode pixels 216. The grid pattern of electrode pixels 212 and the gaps 218 between electrode pixels 214 and 216 provides more electrode pixels of opposite polarity (e.g., positive to negative) than conventional electroadhesive systems. For example, conventional electroadhesive systems have two opposing integrated electrodes (e.g., a positive electrode and a negative electrode) with a gap between them. The integrated electrodes form electrodes of opposite polarity along each connected joint.

[0034]

[0050] System 200 generates electrostatic fields at each set of electrode pixels 214 and electrode pixels 216 of opposite polarity. When used to lift an object, each electrostatic field generates an adhesive force by rearranging (e.g., polarizing) the object's charges so that positive charges in the object are attracted to the negative electrode and negative charges in the object are attracted to the positive electrode. Thus, the pixelated pad 202 of system 200 with its interdigitated electrodes is an improvement over conventional systems because the improved system 200 has more electrodes of opposite polarity, which can generate more electrostatic fields than conventional systems, resulting in increased adhesion forces.

[0035]

[0051] Furthermore, system 200 is an improvement over conventional systems because the improved system 200 can more reliably lift objects due to its anisotropic electrical properties at various alignment angles. For example, the improved system 200 can lift an anisotropic dry carbon fiber ply when the electrode pixels 212 are aligned along the length of the carbon strands of the carbon fiber ply (e.g., positioned at a 0-degree angle). When aligned, the electrode pixels 212 create polarized regions along the length of the tow rather than forcing current to flow along the conductive length of the carbon strands. Therefore, the improved system 200 can reliably lift objects due to its anisotropic electrical properties regardless of the alignment of the electrode pixels 212.

[0036]

[0052] A power supply (not shown) provides power to the pixelated pads 202. The power supply includes a negative voltage input 213 and a positive voltage input 215. The voltage inputs 213 and 215 are shown with dashed lines because the power inputs are on the opposite side of the substrate 210, rather than on the side of the multiple electrode pixels 212, and are hidden from view in FIG. 2 . In some embodiments, the substrate 210 may include multiple layers. Thus, references to the substrate 210 may refer to all layers of the substrate 210, and references to a “side” of the substrate 210 are generally made in relation to the entire substrate, with one side being the top or upper layer and the other side being the bottom or lower layer. As further described in connection with FIGS. 3A-4 , the negative voltage input 213 is connected to the negative electrode pixel 214, and the positive voltage input 215 is connected to the positive electrode pixel 216 through multiple vias 220 in the substrate 210. Via 220 is shown as a dashed circle on electrode pixel 212 to illustrate that it is hidden from the perspective of FIG.

[0037]

[0053] The system 200 further includes a controller 204, a motion system 206, and a distance measurement system 208. The controller 204 is configured to individually energize the electrode pixels 214 and 216. For example, the controller 204 may selectively energize separate zones or individual electrode pixels of the electrode pixels 214 and 216, as described in connection with Figures 6A and 6B. The controller 204 may also energize the entire plurality of electrode pixels 212. In some embodiments, as previously described, the controller 204 may selectively energize each pixel of the plurality of electrode pixels 212 as a negative electrode pixel 214, a positive electrode pixel 216, or no polarity (powered or unpowered).

[0038]

[0054] The motion system 206 is configured to position the substrate proximate to the object to be grasped. For example, the motion system 206 may include a robotic system such as a gantry or arm attached to the pixelated pad 202 and using the pixelated pad 202 as an end effector. The controller 204 may be configured to control the operation of the motion system 206.

[0039]

[0055] The distance measurement system 208 is configured to measure the distance between a portion of the pixelated pad 202, such as the substrate 210, and an object to be grasped. For example, the distance measurement system 208 may be used to position the substrate 210 a predetermined distance from an object before the motion system 206 moves the pixelated pad 202 into contact with the object. The distance measurement system 208 may be used to determine whether the pixelated pad 202 is in contact with the object before energizing the pixelated pad 202. This is useful for preventing the motion system 206 from partially lifting the object (e.g., a dry carbon fiber ply) and damaging the object as it moves the pixelated pad 202 into place. In certain embodiments, the electrode pixels 212 may protrude from the substrate 210, so that a portion of the pixelated pad 202 may contact the object even when the substrate 210 is a predetermined distance from the object. Additionally, positioning pixelated pad 202 prior to energization prevents system 200 from affecting other objects, such as remnant portions around a ply being cut and lifted from a sheet of ply. Distance measurement system 208 may also be configured to determine the orientation of pixelated pad 202 in relation to an object. For example, distance measurement system 208 may determine the shape of the object being electrostatically gripped.

[0040]

[0056] Based on the shape of the object, the distance measurement system 208 may determine how to rotate or translate the pixelated pad 202 in three-dimensional space to align the pixelated pad 202 with the object. Aligning the pixelated pad 202 may advantageously position the pixelated pad 202 so that a subset of the plurality of electrode pixels 212 can be energized to selectively lift the object shown in FIGS. 6A and 6B . The controller 204 may be configured to interface with the distance measurement system 208 and may use data (e.g., measurements) received from the distance measurement system 208 to control the operation of the motion system 206. The controller 204 may further be configured to energize a subset of the plurality of electrode pixels 212 based on the shape of the object determined by the distance measurement system 208. For example, the controller 204 may energize the subset of electrode pixels based on the perimeter of the shape of the object. The distance measurement system 208 may include at least one of a laser, ultrasonic, photoelectric, or optical measurement system. The distance measurement system 208 may also include one of a number of position sensors, such as an encoder or angle sensor, for sensing the position or angle of the object or pixelated pad 202. Additional sensors may also be used to sense the position or angle, as described in connection with FIG.

[0041]

[0057] Various systems and sensors advantageously provide data related to the position of the pixelated pad 202 relative to the object. In some embodiments, the systems and sensors may be part of other systems. For example, the sensors may include encoders integrated into the robotic arms of the motion system 206.

[0042]

[0058] In some embodiments, the substrate 210 is flexible or includes flexible or articulated portions, which can advantageously allow the pixelated pad 202 to conform to non-planar shapes of objects. For example, the substrate 210 may be used to lift dry carbon fiber plies from a curved table or a pre-formed piece of carbon fiber. A flexible substrate 210 can bend the pixelated pad 202 to conform to the curve of the table, reducing the amount of air gap between the pixelated pad 202 and the ply. Reducing the air gap advantageously increases the adhesion provided by the pixelated pad 202. In some embodiments, the substrate 210 is a printed circuit board (PCB) or a flexible PCB. In some embodiments, the plurality of electrode pixels 212 may be affixed to the substrate 210 by various means, including adhesives or solder, or may be formed as a layer on the substrate 210.

[0043] An example of a pixelated pad for grasping an object

[0059] 3A shows a partial top view of a pixelated electroadhesive system 200 in accordance with another embodiment of the present disclosure. Specifically, FIG. 3A shows a close-up view of multiple electrode pixels 212 and gap 218 between electrode pixels 214 and 216.

[0044]

[0060] The plurality of electrode pixels 212 are disposed on the top surface of the substrate 210, where "top" refers to the orientation shown on the page of FIG. 3B. For example, the plurality of electrode pixels 212 are disposed on a first surface 311A ​​of a core layer 311 of the substrate 210. The core layer 311 is further described in FIG. 3B. The electrode pixels 214 and 216 can vary in size or shape. In the illustrated embodiment, the electrode pixels 214 and 216 are rectangular and approximately 5 mm (millimeters) by 50 mm in size. In some embodiments, the electrode pixels 214 and 216 can be 5 mm by 15 mm. In some embodiments, different dimensions can be used for the electrode pixels 214 and 216. In relation to measurements of the shape of the electrode pixels 214 and 216, "approximately" can mean a range of ±1 mm. In other embodiments, the electrode pixels 214 and 216 can be different shapes, as described in relation to FIGS. 2, 5B, and 5C. In the illustrated embodiment, the size of the gap 218 is generally no more than approximately 1 mm, although other gap sizes may be used in some embodiments. Generally speaking, decreasing the size of the gap 218 results in increased adhesion. Thus, a gap size of approximately 1 mm or less advantageously enhances the adhesion of the pixelated pad 202 compared to the larger gap sizes used in conventional electroadhesive systems. With respect to the size of the gap 218, "approximately" may mean within a ±20% range. In some embodiments, the size of the gap 218 is no more than approximately 2 mm. The via 220 is indicated by a dashed circle on the plurality of electrode pixels 214 and 216 to illustrate that it is hidden from the perspective of FIG. 3A (as shown in FIG. 3B ). In some embodiments, the via 220 may be located elsewhere, such as at the edge of each electrode pixel 214 and 216. In some embodiments, the via 220 may extend through the electrode pixels 214 and 216 as a through-hole.

[0045]

[0061] 3B shows a cross-sectional view of a pixelated electroadhesive system 200 in accordance with another embodiment of the present disclosure. Specifically, FIG. 3B shows the different layers of pixelated pad 202.

[0046]

[0062] As previously described, the plurality of electrode pixels 212 (e.g., electrode pixels 214 and 216) are disposed on a first surface 311A ​​of a core layer 311 of the substrate 210. The core layer 311 may function as a bonding layer, an insulating layer, or a structural support layer for the substrate 210. In some embodiments, the core layer 311 may include a dielectric medium, such as glass or at least one of polymers, such as polytetrafluoroethylene (PTFE), polypropylene, and polyethylene. For example, the core layer 311 may be an acrylic wafer.

[0047]

[0063] The dielectric layer 322 is disposed over the electrode pixels 214 and 216 such that the dielectric layer 322 is disposed between the electrode pixels 214 and 216 and the object to be grasped. The dielectric layer 322 can be thin enough so that it does not reduce the electrostatic field of the electrode pixels 214 and 216. The thickness of the dielectric layer 322 can vary depending on the dielectric medium. Furthermore, the dielectric layer 322 can include a dielectric medium or material and be disposed within the gap 218, as previously described. In some aspects, the dielectric layer 322 includes a different dielectric medium than the core layer 311. In some aspects, the dielectric layer 322 includes polyimide or fiberglass prepreg. In some aspects, the dielectric layer 322 is the air surrounding the electrode pixels (e.g., ambient air), and is not a layer that actually contains something, so it is advantageous to use the bare electrode pixels 214 and 216 to grasp a non-conductive material.

[0048]

[0064] As shown in FIG. 3B , the plurality of conductive control traces 324 are disposed on a different layer than the electrode pixels 214 and 216. The plurality of conductive control traces 324 may be disposed on the bottom surface of the substrate 210, where "bottom" refers to the orientation shown on the page of FIG. 3B . For example, the plurality of conductive control traces 324 may be disposed on the second surface 311B of the core layer 311 of the substrate 210, the second surface 311B being the opposite surface of the core layer 311 rather than the first surface 311A. Each of the electrode pixels 214 and 216 is connected to the plurality of conductive control traces 324 by vias 220 in the substrate 210. As shown in FIG. 3B , the voltage inputs 213 and 215 are disposed on the second surface 311B of the core layer 311 and connected to the conductive control traces 324.

[0049]

[0065] In some embodiments, voltage inputs 213 and 215 and / or conductive control trace 324 are located at different locations (or multiple locations). For example, substrate 210 may include multiple layers. Voltage inputs 213 and 215 and conductive control trace 324 may each be located on different layers of substrate 210 or between two different layers. Negative voltage input 213 and positive voltage input 215 may be located such that voltage inputs 213 and 215 are not located on the same layer or between layers of substrate 210. Conductive control trace 324 may also be located such that different ones of conductive control trace 324 are not located on the same layer or between layers. Thus, voltage inputs 213 and 215 and conductive control trace 324 may be separated between layers. In some embodiments, via 220 may not form a through hole through all layers of the substrate, but instead may form an opening through some of the layers of the substrate.

[0050]

[0066] In some embodiments, the voltage inputs 213 and 215 may be connected to the electrode pixels 214 and 216 by a PCB that is separate from the substrate 210. For example, the PCB may include the voltage inputs 213 and 215 and a plurality of conductive control traces 324, each of the vias 220 in the substrate 210 may terminate in a socket or pin, and the PCB may be configured to connect the conductive control traces 324 to the sockets or pins of the vias 220. The PCB may be detachable to allow the conductive control traces 324 to be reconfigured. A detachable PCB is advantageous because it allows the voltage inputs 213 and 215 to be supplied to the electrode pixels 214 and 216 in different configurations. In an embodiment, one configuration may supply the voltage input 213 or 215 to each of the electrode pixels 214 and 216. Another configuration may supply the voltage input 213 or 215 to different regions or zones of the electrode pixels 214 and 216. In some embodiments, the controller may be coupled to a detachable PCB and configured to provide voltage inputs 213 and 215 to electrode pixels 214 and 216 .

[0051]

[0067] In one embodiment, each electrode pixel of the plurality of electrode pixels 212 is configured to be energized with a voltage scale ranging from 0 volts (V) to 4,000 V. In another embodiment, each electrode pixel of the plurality of electrode pixels 212 is configured to be energized with a voltage scale ranging from 0 volts to 1,500 V. In some embodiments, other voltage scales may be used to energize the plurality of electrode pixels 212. The voltage inputs 213 and 215 may be controlled by the controller 204, as described in connection with FIGS. 2 and 7, or by a controller connected to a power supply. The conductive control traces are further described in connection with FIG. 4.

[0052]

[0068] The pixelated pad 202 may include at least one heating element 328. The at least one heating element 328 is configured to heat the dielectric layer 322, which, as experimentally observed, advantageously enhances adhesion. The heating element 328 is shown disposed between the electrode pixels 214 and 216 and the core layer 311 and is configured to heat the dielectric layer 322 by electrical conduction through the electrode pixels 214 and 216. The vias 220 may further extend through the at least one heating element 328, and the at least one heating element 328 may be connected to one of the conductive control traces 324 through one or more vias 220. In some embodiments, the heating element 328 may be configured to heat separate zones of the electrode pixels 214 and 216, individual electrode pixels, or the entire plurality of electrode pixels 212. For example, heating element 328 may include multiple heating elements 328, with each heating element of multiple heating elements 328 corresponding to and positioned behind a zone or region of electrode pixels 214 and 216. Each heating element of multiple heating elements 328 may also be positioned behind an individual electrode pixel of electrode pixels 214 and 216 and / or within gap 218. In some embodiments, heating element 328 may be positioned between different layers of pixelated pad 202 than those shown in FIG. 3B . In some embodiments, heating element 328 need not be positioned between electrode pixels 214 and 216 and the object to be grasped.

[0053]

[0069] In some embodiments where the substrate 210 includes multiple layers (referred to as a multi-layer substrate), the dielectric layer 322, the electrode pixels 214 and 216, the gap 218, the at least one heating element 328, the core layer 311, the voltage inputs 213 and 215, and the conductive control trace 324 may each form at least one layer of the multiple layers of the substrate 210. For example, the electrode pixels 214 and 216 and the gap 218 may form at least one layer of the substrate 210. The conductive control trace 324 may form a different layer of the substrate 210. The vias 220 may connect the conductive control trace 324 to the electrode pixels 214 and 216 by through-hole vias, blind vias, and / or buried vias. In some embodiments, the multi-layer substrate may include at least one prepreg layer that may connect different layers of the multi-layer substrate. The core layer 311 may also include one or more prepreg layers. In some embodiments, the multilayer substrate includes a dielectric layer between each layer containing electrode pixels 214 and / or 216. The dielectric layer prevents each conductive layer containing electrode pixels 214 and 216 from arcing to another conductive layer. In some embodiments, the multilayer substrate may include only dielectric layers and electrode pixel layers. For example, the layers of the multilayer substrate may be arranged as follows: dielectric-electrode pixel-dielectric-electrode pixel-dielectric. The dielectric-electrode pixel multilayer substrate may further interface with a detachable PCB configured to provide voltage inputs 213 and 215 to the electrode pixels through vias, as previously described.

[0054]

[0070] Some embodiments further include a temperature sensor, such as a thermocouple, to sense the temperature of the heating element 328 or another portion of the pixelated pad 202, as described in connection with FIG. 7. The temperature sensor may be part of the heating element 328 or may be attached to the heating element 328. The temperature sensor may also be attached to the substrate 210 or one or more of the electrode pixels 214 and 216. A temperature sensor is advantageous because it allows for the temperature of the heating element 328, the substrate 210, and / or the electrode pixels 214 and 216 to be adjusted by controlling power to the heating element 328.

[0055]

[0071] In some embodiments, a controller, such as the controller 204 described in connection with FIGS. 2 and 7 , is configured to control the heating elements 328. For example, the controller may be configured to energize the heating elements 328 and adjust the temperature of the dielectric layer 322 by energizing at least one heating element 328 configured to heat the dielectric layer 322 via the controller. The heating elements 328 may require less voltage or power than the multiple electrode pixels 212. In some embodiments, a temperature sensor may interface with the controller to adjust the temperature of the dielectric layer 322. For example, the system controller may use data from the temperature sensor to adjust the temperature of the dielectric layer 322 by controlling the heat output by the heating elements 328. Data from the temperature sensor can be used to form a control feedback loop, which may be implemented by the control system of FIG. 7 . In some embodiments, the multiple heating elements 328 may be configured to heat different zones or regions of the dielectric layer 322. Each heating element of the multiple heating elements 328 may be selectively energized via the controller. For example, each heating element may be associated with a corresponding temperature sensor, and a controller may use data from the temperature sensors to independently control the heat output by each heating element. In some embodiments, the zones or regions of the dielectric layer 322 heated by the multiple heating elements 328 may coincide with the zones or regions of the electrode pixels 214 and 216.

[0056]

[0072] The pixelated pad 202 may include a flexible support layer 326 in contact with the substrate 210. The flexible support layer 326, as described above, is configured to allow the pixelated pad 202 to conform to the surface of the object being gripped. For example, the pixelated pad 202 may be used to lift a dry carbon fiber ply from a table or a piece of pre-formed carbon fiber. The surface of the table on which the ply rests, or the surface of a portion of the pre-formed carbon fiber, may be uneven, causing the ply or piece to be uneven when lifted. The flexible support layer 326 allows the pixelated pad 202 to bend to conform to the contours of the table, reducing the amount of air gap between the pixelated pad 202 and the ply. Reducing the air gap advantageously increases the adhesion provided by the pixelated pad 202. As shown, flexible support layer 326 is attached to second surface 311B of core layer 311 and at least partially surrounds voltage inputs 213 and 215 and conductive control traces 324, advantageously preventing voltage inputs 213 and 215 and conductive control traces 324 from contacting items outside of pixelated pads 202 during use. In some embodiments, flexible support layer 326 may be a layer of substrate 210. For example, core layer 311 may comprise a flexible material and function as flexible support layer 326.

[0057]

[0073] Figure 4 shows a wiring diagram for the back of a pixelated electroadhesive system 200 according to another embodiment of the present disclosure. Specifically, Figure 4 shows an example of how conductive control traces 324 may be connected to electrode pixels 214 and 216 of a pixelated pad 202. In various aspects, power and control lines can enter the pixelated pad 202 via connectors attached directly to the back of the pad (e.g., the side opposite the gripping surface).

[0058]

[0074] As shown in FIG. 4 , the voltage inputs 213 and 215 are disposed along the periphery 230 of the plurality of electrode pixels 212. The voltage inputs 213 and 215 are connected to conductive control traces 324, which are shown to include negative control traces 433 and positive control traces 435. For example, the negative voltage input 213 is connected to the negative control trace 433, and the positive voltage input 215 is connected to the positive control trace 435. The conductive control traces 324 are further connected to the plurality of electrode pixels 212, as described in connection with FIG. 3B . In the illustrated embodiment, each of the negative electrode pixels 214 is connected to the negative control trace 433, and each of the positive electrode pixels 216 is connected to the positive control trace 435. The individualized connections from the conductive control traces 324 to the plurality of electrode pixels 212 allow each of the electrode pixels 214 and 216 to be individually energized. Each of the electrode pixels 214 and 216 is configured to be energized over a voltage scale ranging from 0V to 4,000V. Thus, the negative voltage input 213 may be configured to be supplied with a voltage between −0 V and −4,000 V, and the positive voltage input 215 may be configured to be supplied with a voltage between 0 V and 4,000 V. In some embodiments, the voltage scale may range from 0 V to 1,500 V.

[0059]

[0075] 4, the conductive control traces 324 follow an interlocked layout, such as a diagonal layout. An interlocked layout is advantageous because it allows the conductive control traces 324 to be disposed on a single layer and connected to each of multiple electrode pixels 212 without overlapping or interfering with other conductive control traces. For example, the interlocked layout of the negative control trace 433 and the positive control trace 435 allows each of the control traces 433 and 435 to be disposed on the second surface 311B of the core layer 311 and connected to each of the electrode pixels 214 and 216, respectively, while maintaining a minimum separation distance from the other conductive control traces. In some embodiments, layouts or patterns other than a diagonal layout may be used for the conductive control traces 324, such as freeform or curved shapes.

[0060]

[0076] In some embodiments, conductive control trace 324 may be a conductor. In some embodiments, conductive control trace 324 may be a track or circuit trace of a printed circuit board, as previously described in connection with FIG. 3B. In some embodiments, conductive control trace 324 may comprise several layers of substrate 210, as previously described in connection with FIG. 3B, which is advantageous because it allows conductive control trace 324 to be connected to electrode pixel 212 without overlapping or interfering with other conductive control traces. In some embodiments, control traces 433 and 435 may be connected to different zones or regions of electrode pixels 214 and 216 instead of to individual electrode pixels.

[0061]

[0077] Although voltage inputs 213 and 215 are each shown as a single line, voltage inputs 213 and 215 may include multiple conductors or circuit traces. For example, there may be one negative voltage input 213 for each negative control trace 433 and one positive voltage input 215 for each positive control trace 435.

[0062]

[0078] In some embodiments, the voltage inputs 213 and 215 may each include a single conductor or circuit trace. For example, a controller, a power distribution module, an in-line switching element, or a power distribution board (collectively referred to as a control trace power supply) may be disposed between the voltage inputs 213 and 215 and the conductive control traces 324. The control trace power supply may be configured to selectively energize each conductive control trace of the conductive control traces 324, and consequently, one or more of the electrode pixels 214 and 216 connected to each conductive control trace 324. The control trace power supply may be configured to energize each electrode pixel of the plurality of electrode pixels 212 with a voltage scale ranging from 0V to 4,000V. In some embodiments, each electrode pixel of the plurality of electrode pixels 212 may be energized with a different voltage, independent of the other electrode pixels of the plurality of electrode pixels 212. In some embodiments, the controller 204 may include a control trace power supply, as described in connection with FIG. 2, such that the controller 204 is configured to selectively energize each of the conductive control traces 324. For example, the controller 204 may energize each of the conductive control traces 324 with a positive voltage or a negative voltage, and may vary between positive and negative voltages as needed. Thus, the configuration of the electrode pixels 214 and 216, as shown in FIG. 5A, may be reconfigured as desired to be different from that shown in FIGS. 2-4.

[0063]

[0079] In some embodiments, voltage inputs 213 and 215 may be configured differently. For example, voltage inputs 213 and 215 may not be located along periphery 230, but may be located inside periphery 230. In some embodiments, voltage inputs 213 and 215 may be located on first surface 311A ​​of core layer 311. For example, voltage inputs 213 and 215 may be connected to control traces 433 and 435, respectively, through vias (not shown).

[0064]

[0080] The discussion relating to Figures 2-4 illustrates different embodiments of system 200 and pixelated pad 202. In some embodiments, different pixelated pads can be used with system 200 or similar pixelated electroadhesive systems, as discussed in connection with Figures 5A-5C.

[0065] Example of different pixel-organized pads

[0081] 5A-5C show different pixelated electroadhesive systems for gripping objects according to embodiments of the present disclosure. Specifically, FIGS. 5A-5C show examples of different electrode layouts for different pixelated pads 502A-502C.

[0066]

[0082] 5A illustrates a different pixelated pad 502A for gripping an object, according to an embodiment of the present disclosure. Specifically, the pixelated pad 502A illustrated in FIG. 5A is an improved version of the comb-like electrode layout of a conventional interdigitated system.

[0067]

[0083] The pixelated pad 502A includes a substrate 510A, which further includes a plurality of electrode pixels 512A. The plurality of electrode pixels 512A are arranged in a grid pattern such that each electrode pixel in the plurality of electrode pixels 512A is adjacent to at least two other electrode pixels in the plurality of electrode pixels 512A. A plurality of gaps 518A separate each electrode pixel in the plurality of electrode pixels 512A. In the illustrated embodiment, the plurality of electrode pixels 512A includes a plurality of negative electrode pixels 514A (two of which are labeled) and a plurality of positive electrode pixels 516A (two of which are labeled). The negative electrode pixels 514A and the positive electrode pixels 516A are each arranged in an interdigitated pattern such that each column of the plurality of electrode pixels 512A alternates. For example, a first column may include only negative electrode pixels 514A, a second column may include only positive electrode pixels 516A, a third column may include only negative electrode pixels 514A, a fourth column may include only positive electrode pixels 516A, and so on. Each column of the plurality of electrode pixels 512A may include two or more electrode pixels. For example, in the illustrated embodiment, each column includes four electrode pixels 514A or 516A. With two or more electrode pixels in each column, a portion of each column can be energized, advantageously enabling the pixelated pad 502 to selectively grip objects, as described in connection with FIGS. 6A and 6B . For example, conventional systems use conventional electrode attachment pads that non-selectively grip all objects that contact or are within a set distance from the pad.

[0068]

[0084] Negative electrode pixels 514 are connected to a negative voltage input 513 via a negative control trace (not shown). Similarly, positive electrode pixels 516 are connected to a positive voltage input 515 via a positive control trace (not shown). The negative and positive control traces (referred to as conductive control traces) are connected to the negative electrode pixels 514 and the positive electrode pixels 516, respectively, via a plurality of vias 520 (four of which are labeled) in the substrate 510, as described in connection with Figures 3A-4. The plurality of vias 520 are shown as dashed circles on the plurality of electrode pixels 512 to illustrate that they are hidden from view in Figure 5A.

[0069]

[0085] In some embodiments, the negative electrode pixels 514A and the positive electrode pixels 516A may be reconfigured as described in connection with FIG. 4 to match the pattern of electrode pixels 214 and 216 shown in FIG. 2, respectively.

[0070]

[0086] In some embodiments, the plurality of electrode pixels 512 may include more or fewer columns or rows. In some embodiments, each column of the plurality of electrode pixels 512 may include a negative and a positive electrode pixel. In some embodiments, more or fewer electrode pixels per column may be used.

[0071]

[0087] 5B illustrates a different pixelated pad 502B for gripping an object, according to an embodiment of the present disclosure. Specifically, the pixelated pad 502B illustrated in FIG. 5B is similar to the pixelated pad 202 of the system 200 described in connection with FIG. 2, except for the layout of the plurality of electrode pixels 512B.

[0072]

[0088] The pixelated pad 502B includes a substrate 510B that further includes a plurality of electrode pixels 512B. The plurality of electrode pixels 512B includes, as shown in one example configuration, a negative electrode pixel 514B and a positive electrode pixel 516B. The negative electrode pixel 514B and the positive electrode pixel 516B may each be reconfigured as described in connection with FIG. 4. A plurality of gaps 518B separate the electrode pixels 514B and 516B.

[0073]

[0089] As shown in the illustrated embodiment, each column may include a different number of electrode pixels. For example, the outer portions of pixelated pad 502B may include more electrode pixels than the inner or central portions. Varying the number of electrode pixels per column allows pixelated pad 502B to selectively grasp objects with different or complex edges with finer control than a pixelated pad having a fixed number of electrode pixels per column. For example, electrode pixels in the outer portions of pixelated pad 502B may be selectively energized to match the shape of the object to be grasped, as described in connection with FIGS. 6A and 6B .

[0074]

[0090] In some embodiments, pixel configured pad 502B may further include multiple vias, positive and negative voltage inputs, and conductive control traces, as described in connection with FIGS.

[0075]

[0091] 5C illustrates a different pixelated pad 502C for gripping an object according to an embodiment of the present disclosure. Specifically, the pixelated pad 502C illustrated in FIG. 5C is similar to the pixelated pad 502B described in connection with FIG. 5B, except for the shape of the substrate 510C and the shape and layout of the plurality of electrode pixels 512C.

[0076]

[0092] Similar to pixelated pad 502B, pixelated pad 502C includes a substrate 510C and a plurality of electrode pixels 512C, each comprising a negative electrode pixel 514C and a positive electrode pixel 516C separated by a plurality of gaps 518C. The plurality of electrode pixels 512C are arranged in a circular pattern (also referred to as a target pattern) having multiple nested rings of electrode pixels. As shown, each electrode pixel in the plurality of electrode pixels 512C has an arc, bow, or semicircle shape and is adjacent to at least two other electrode pixels of opposite polarity. For example, a negative electrode pixel 514C is adjacent to at least two positive electrode pixels 516C. In the illustrated embodiment, the electrode pixels in each ring of the circular pattern alternate between negative electrode pixels 514C and positive electrode pixels 516C. The electrode pixels further alternate between negative electrode pixels 514C and positive electrode pixels 516C radially outward from the central ring of the circular pattern to the outer rings. Electrode pixels 514C and 516C vary in shape and size. Each electrode of the plurality of electrode pixels 512C may be selectively energized, advantageously allowing pixelated pad 502C to selectively grasp an object, as described in connection with Figures 6A and 6B. Negative electrode pixel 514C and positive electrode pixel 516C may each be reconfigured, as described in connection with Figure 4.

[0077]

[0093] In some embodiments, each ring of the circular pattern includes only negative electrode pixels 514C or only positive electrode pixels 516C. In some embodiments, the plurality of electrode pixels 512C may be arranged in a spiral pattern. In some embodiments, the circular pattern may be considered a grid pattern.

[0078]

[0094] In some embodiments, pixelated pad 502C may further include multiple vias, positive and negative voltage inputs, and conductive control traces, as described in connection with FIG. 5A.

[0079]

[0095] 5A-5C illustrate different embodiments of pixelated pads. For example, pixelated pads 502A-402C, respectively, are different from pixelated pad 202, as previously described in connection with FIGS. 2-4. In some embodiments, each of pixelated pads 502A-402C may be used in conjunction with system 200, as previously described in connection with FIG. 2. As previously described, a subset of the electrode pixels of pixelated pad 202 or 502A-402C may be energized to selectively grip an object, as further described in connection with FIGS. 6A and 6B.

[0080] Example of Selective Grasping of Objects Using Pixelated Pads

[0096] 6A and 6B illustrate a subset 632 of electrode pixels configured to grasp different objects, according to an embodiment of the present disclosure. Specifically, FIGS. 6A and 6B illustrate how one or more subsets of the plurality of electrode pixels 212 (e.g., subset 632 of electrode pixels) are energized to selectively grasp (or lift) different objects. The representations in FIGS. 6A and 6B are schematic in nature and are not intended to be perspective views of a pixelated pad (e.g., pixelated pad 202 or 502A). For illustrative purposes, shading is used to indicate some of the objects that may be lifted. The subset 632 of the plurality of electrode pixels 212 is shown with solid lines, while the remaining electrode pixels of the plurality of electrode pixels 212 (e.g., non-energized electrode pixel 631) are shown with dashed lines. For example, when an object is grasped, the subset 632 of electrode pixels is energized and the non-energized electrode pixel 631 is not energized.

[0081]

[0097] As shown in FIG. 6A , the plurality of electrode pixels 212 are surrounded by a periphery 230. When used to lift an object 640, the plurality of electrode pixels 212 are positioned above the object 640 such that the object 640 is contained within the periphery 230 when viewed from above, as shown in FIG. 6A . In the illustrated embodiment, only the electrode pixels above the object 640 are energized. For example, each electrode pixel of the subset of electrode pixels 632 is above at least a portion of the object 640. Energizing only the subset of electrode pixels 632 advantageously allows the plurality of electrode pixels 212 to reliably lift the object 640 using fewer electrode pixels and less energy than conventional systems, while ensuring that the edges of the object 640 are not bent or damaged.

[0082]

[0098] A controller (e.g., controller 204 of FIGS. 2 and 7 ) may be provided with instructions to energize a subset of electrode pixels (e.g., subset of electrode pixels 632 and electrode pixel 212) of the plurality of electrode pixels. The subset of electrode pixels 632 may be based on the shape of the object 640 to be grasped. In some aspects, the controller may be configured to determine the shape of the object 640 and energize the subset of electrode pixels 632 of the plurality of electrode pixels based on the shape of the object 640. For example, a distance measurement system (e.g., distance measurement system 208 of FIGS. 2 and 7 ) may determine the position and orientation of the object 640 in relation to the plurality of electrode pixels 212. The controller may interface with the distance measurement system to determine the shape and orientation of the object 640. The controller may determine the subset of electrode pixels to energize (e.g., subset of electrode pixels 632) based on the shape and orientation of the object 640. In some aspects, the controller determines the subset of electrode pixels with the minimum number of electrode pixels over the object 640. In some embodiments, the controller determines a subset of electrode pixels (e.g., first subset of electrode pixels 632A of FIG. 6B ) with the largest number of electrode pixels that do not extend beyond the periphery of the object (e.g., first object 642 of FIG. 6B ). In some embodiments, the controller determines a subset of electrode pixels that meets a power or adhesion threshold. The controller may further control a motion system (e.g., motion system 206 of FIGS. 2 and 7 ) to position and orient the determined subset of electrode pixels (e.g., subset of electrode pixels 632) above the object 640.

[0083]

[0099] 6B , the plurality of electrode pixels 212 can include multiple subsets 632 of electrode pixels. For example, the plurality of electrode pixels 212 can include a first subset 632A of electrode pixels and a second subset 632B of electrode pixels. Each subset can correspond to an object to be lifted. In the illustrated embodiment, the first subset 632A of electrode pixels lifts a first object 642, and the second subset 632B of electrode pixels lifts a second object 646.

[0084]

[0100] First object 642 is a portion cut from ply sheet 643. The remaining portion of ply sheet 643 is remnant portion 644. First subset of electrode pixels 632A is aligned with first object 642 such that each electrode pixel of first subset of electrode pixels 632A is contained within the periphery of first object 642. When energized, first subset of electrode pixels 632A lifts first object 642 but does not lift remnant portion 644. Thus, first subset of electrode pixels 632A selectively lifts first object 642 while leaving remnant portion 644 intact.

[0085]

[0101] The second object 646 is disposed near the third object 648. The second subset of electrode pixels 632B is aligned such that each electrode pixel of the second subset of electrode pixels 632B overlies at least a portion of the second object 646, but none of the electrode pixels overlies the third object 648. For example, the unenergized electrode pixel 639 overlies the second object 646 and the third object 648. Although the electrode pixel 639 overlies the second object 646, the second subset of electrode pixels 632B does not include the electrode pixel 639. Thus, when energized, the second subset of electrode pixels 632B selectively lifts the second object 646 while leaving the third object 648 intact.

[0086] Exemplary Control Architecture

[0102] 7 is a block diagram of a control architecture for a gripper device according to an embodiment of the present disclosure. A computer 710 (such as the computing system 1600 described in more detail with respect to FIG. 16 ) communicates with an embedded controller 720 (such as another example of the computing system 1600) to manage and control various electrode pixels 730 such as those in the gripper device 110 (e.g., FIG. 1 ). In various embodiments, the computer 710 is a control station used by a user or operator to program or generally control the gripper device 110, including its operation within an environment. In turn, the embedded controller 720 translates instructions related to activating and deactivating electrode pixels into individual activate / deactivate signals to selectively power some of the electrodes of the gripper device 110.

[0087]

[0103] Embedded controller 720 communicates with electrode pixels 730, distribution bus 740, and power supply 750 to manage gripper device 110, which electrode pixels to activate or deactivate, when to activate or deactivate those electrode pixels, and what voltages to apply to the various activated electrode pixels. Electrode pixels 730 may represent some or all of the electrode pixels of gripper device 110, which may be arranged according to various layouts, such as those described in connection with Figures 2-6B.

[0088]

[0104] An alternating current (AC) source 760 (such as a manufacturing facility's mains power supply) provides the power used to operate the electrode pixels 730, and a power supply 750 converts the incoming AC power via direct current (DC) power to drive the electrode pixels 730 at a commanded voltage level. The power supply 750 includes an AC / DC rectifier 751 for converting the AC from the AC source to DC, and a high-voltage DC (HVDC) booster 752 for converting the voltage level of the DC power to a desired voltage. The boosted DC voltage is then supplied to a grip / release (GR) circuit under the control of an embedded controller 720 to set a desired system state or drive frequency for the electrode pixels 730.

[0089]

[0105] Although generally described in connection with a single phase of AC power, the power supply 750 may use an AC source 760 that provides two-phase, three-phase, or more multi-phase power. Additionally or alternatively, the embedded controller 720 may use multi-phase power supplies 750, each associated with one phase of the power provided by the multi-phase AC source 760. Additionally or alternatively, the electrode pixels 730 may be provided in several independently controllable groups, and thus several power supplies 750 may be provided, each associated with one group of the electrode pixels 730.

[0090]

[0106] A distribution bus 740 carries the converted voltage from the GR circuitry to the electrode pixels 730 and may receive instructions from the embedded controller 720 to regulate which electrode pixels 730 receive power from a given power supply 750 .

[0091] Exemplary Voltage Driver Circuit

[0107] 8A-8C illustrate exemplary voltage driver circuits as may be provided in power supplies 750 of FIG. 7 according to embodiments of the present disclosure. In various embodiments, when several power supplies 750 are provided for control of individual elements of the gripping surface of gripper device 110, gripper device 110 may include one or more of the circuit layouts shown in FIGS. 8A-8C.

[0092]

[0108] FIG. 8A illustrates a half-bridge center-tapped transformer drive, FIG. 8B illustrates a single-ended drive flyback converter, and FIG. 8C illustrates a Royer oscillator drive, which are non-limiting examples of hardware configurations for power supply 750. Each figure includes a transformer 830 that provides at least one power input 810a-810b (generally or generically, power input 810) for DC power and at least one power output 820a-820b (generally or generically, power output 820) for AC power. As shown in FIG. 8C, transformer 830 may be divided into several windings 835a-835d.

[0093]

[0109] Various hardware components, such as resistors 840 (including variable resistors), capacitors 850, and switching elements 860 (e.g., switches, metal-oxide field-effect transistors (MOSFETs), relays, insulated-gate bipolar transistors (IGBTs), optocouplers), may be employed in each of the hardware configurations and controlled via various logic elements 870 (e.g., logic gates, embedded microcontrollers, external computing devices) to convert a DC input into an AC output of a desired amplitude and frequency. Additionally, an operational amplifier 880 and a diode 890 may be provided within the hardware configurations.

[0094]

[0110] Those skilled in the art will appreciate that various configurations for the power supply have different advantages and that the control logic, hardware selections, and electrical values ​​(e.g., capacitance, resistance, turns ratio) can be configured for a desired output AC power based on the input DC power, or a combination thereof.

[0095] Exemplary Power Control Circuit

[0111] 9A shows a power control architecture for a tile structure with a high-voltage generator according to an embodiment of the present disclosure. An AC source 940 (such as power supply 750) selectively applies AC voltages to electrode pixels 970 according to inputs set by matrix control elements 910 to select one or more electrode pixels 970 for actuation.

[0096]

[0112] Matrix control element 910, which may be a computing device such as computing system 1600 described in connection with FIG. 16, sends signals to positive switching elements 920a-920b (generally or collectively, positive switching elements 920) and negative switching elements 930a-930b (generally or collectively, negative switching elements 930) to control whether a given gripping electrode pixel 970 receives a positive polarity voltage (e.g., via positive switching element 920) or a negative polarity voltage (e.g., via negative switching element 930).

[0097]

[0113] In various aspects, the matrix control element 910 sends a first signal to the first positive switching element 920a and the first negative switching element 930a, and the first signal inverter 960a (generally or collectively, signal inverter 960) inverts one of the signals (e.g., to activate one of the first positive switching element 920a and the first negative switching element 930a and deactivate or leave the other in an inactivated state). Similarly, the matrix control element 910 sends a second signal to the second positive switching element 920b and the second negative switching element 930b, and the second signal inverter 960b inverts one of the signals (e.g., to activate one of the second positive switching element 920b and the second negative switching element 930b and deactivate or leave the other in an inactivated state). Thus, the control signal allows one of the pair of positive switching elements 920 and negative switching elements 930 to be activated at any one time, thereby reducing the risk of shorting out the electrical elements.

[0098]

[0114] Each second positive switching element 920b and second negative switching element 930b is associated with a respective electrode pixel 970, and various additional second positive switching elements 920b and second negative switching elements 930b (not shown) are provided for individual control of the additional electrode pixels 970. Thus, the matrix control element 910 may be in communication with several pairs of second positive switching elements 920b and second negative switching elements 930b to individually control a corresponding plurality of electrode pixels 970.

[0099]

[0115] Electrode pixels 970, according to the present disclosure, are modular units of control for gripping an object via gripper device 110. Gripper device 110 may include several electrode pixels 970, each individually controllable and powerable, for gripping and releasing an object. Each electrode pixel 970 can exhibit one of three charge states (e.g., positive X kilovolts (kV), negative X kV, or unpowered or grounded). Thus, the range of voltage experienced within an electrode pixel 970 will be between 0 and 2X kV when gripping an object.

[0100]

[0116] To reach a desired voltage level (e.g., ±X kV) within electrode pixel 970, a first positive switching element 920a and a first negative switching element 930a control the input voltage provided to high voltage converter 950 from AC source 940. The high voltage converter rectifies and increases the voltage received from AC source 940 to provide output voltages of two different polarities (e.g., ±X kV) for use in electrode pixel 970. In various aspects, high voltage converter 950 is a Cockcroft-Walton ladder that provides a positive voltage amplified to +X kV and a negative voltage amplified to −X kV for use in electrode pixel 970 via a capacitor ladder with cross-linked diode “stages,” with the diodes for the positive polarity output oriented opposite to the diodes for the negative polarity output.

[0101]

[0117] 9B shows a power control architecture for a tile structure with a high-voltage generator according to an embodiment of the present disclosure. An AC source 940, such as power supply 750, selectively applies AC voltages to electrode pixels 970 a and 970 b according to inputs set by respective matrix control elements 910 a and 910 b, each time a signal sent from embedded controller 720 drives two or more electrode pixels 970 a and 970 b with different (e.g., positive and negative) polarities.

[0102]

[0118] An embedded controller 720, which may be a computing device such as the computing system 1600 described in connection with Figure 16, sends signals to the positive switching element 920 and the negative switching element 930 to control whether a given electrode pixel 970 receives a positive polarity voltage (e.g., via the positive switching element 920) or a negative polarity voltage (e.g., via the negative switching element 930). In various aspects, the circuit layout of the switching elements may be the circuit layout described in more detail in connection with Figure 10 with respect to the grip and release circuit 1020.

[0103]

[0119] In various embodiments, the matrix control element 910 further controls when the associated electrode pixel 970 is activated by the applied voltage. Thus, the control signal allows one of the pair of positive switching element 920 and negative switching element 930 to be activated at any one time, thereby reducing the risk of shorting out the electrical elements.

[0104]

[0120] Each second positive switching element 920b and second negative switching element 930b is associated with a respective electrode pixel 970, and various additional second positive switching elements 920b and second negative switching elements 930b (not shown) are provided for individual control of the additional electrode pixels 970. Thus, the matrix control element 910 may be in communication with several pairs of second positive switching elements 920b and second negative switching elements 930b to individually control a corresponding plurality of electrode pixels 970.

[0105]

[0121] The high voltage converter rectifies and increases the voltage received from the AC source 940 to provide output voltages of two different polarities (e.g., ±X kV) for use by the electrode pixels 970. In various embodiments, the high voltage converter 950 is a Cockcroft-Walton ladder that provides a positive voltage boosted to +X kV and a negative voltage boosted to −X kV for use by the electrode pixels 970 via a ladder of capacitors with cross-linked diode “stages,” with the diodes for the positive polarity output oriented opposite to the diodes for the negative polarity output.

[0106] Exemplary Tile and Zone Switching Circuitry

[0122] FIG. 10 illustrates a tile and zone switching unit 1000 according to one embodiment of the present disclosure. A DC source 1010, such as a power supply 750, is connected to two or more grip and release circuits 1020 (e.g., at least one for each polarity), which are then selectively connected to one or more tiles 1030. In various embodiments, at least two grip and release circuits 1020 are provided, one for each polarity, with each manipulator and array of electrode pixels. The grip and release circuits 1020 may be understood as separate grip and release circuits or may be combined and arranged with switching elements. While FIG. 10 illustrates all switches 1021a-1021e (generally or collectively, switches 1021) as single-pole, single-throw switches (in a normally open configuration), various other types of switches 1021 may be used (including gate semiconductors), and various numbers of switches 1021 may be of various different types or configurations.

[0107]

[0123] The grip and release circuit 1020 includes a first switch 1021a connected between the DC source 1010 and a first node 1022a, a capacitor 1023 connected between the first node 1022a and a second node 1022b, a second switch 1021b connected between the second node 1022b and a third node 1022c (e.g., an electrode control node) for the various grip tiles 1030, a third switch 1021c connected between the second node 1022b and ground, a fourth switch 1021d connected between the first node 1022a and ground, and a fifth switch 1021e connected between the first node 1022a and the third node 1022c.

[0108]

[0124] Each of the switches 1021 may be controlled individually or collectively (e.g., by logic controller 1110 described in connection with FIG. 11 ) to change the voltage source and voltage polarity supplied to the associated grip tile 1030. For example, power may be supplied from DC source 1010 to actuate grip tile 1030 and simultaneously charge capacitor 1023. In another embodiment, power may be supplied from capacitor 1023 to actuate grip tile 1030 with a polarity opposite to that received from DC source 1010 (e.g., discharging capacitor 1023).

[0109]

[0125] In a first configuration, when applying power from the DC source 1010 (to actuate the grip tiles 1030 and charge the capacitors 1023), the first switch 1021a, the third switch 1021c, and the fifth switch 1021e are closed, while the second switch 1021b and the fourth switch 1021d are open. In the first open / closed configuration of the switches 1021, the DC source 1010 provides an output voltage of a first polarity to the grip tiles 1030 and charges the capacitors 1023, and the grip-release circuit 1020 is controllable to reverse its open and closed states (e.g., opening the close switch 1021 and closing the open switch 1021) as part of a polarity-alternating duty cycle to grip or release an object.

[0110]

[0126] When flipped, the grip and release circuit 1020 provides an output voltage with a second (opposite) polarity, and in the second configuration, the first switch 1021a, the third switch 1021c, and the fifth switch 1021e are open, while the second switch 1021b and the fourth switch 1021d are closed. Similarly, when the switches are in the second configuration, the grip and release circuit 1020 is controllable to reverse the open and closed states (e.g., opening the close switch 1021 and closing the open switch 1021) as part of a polarity-altering duty cycle for gripping an object or for gripping a new or previously released object.

[0111]

[0127] As will be appreciated, other open / closed configurations of switch 1022 are possible for discharging capacitor 1023 without powering grip tile 1030 (e.g., bleeding off charge), for powering grip tile 1030 from DC source 1010 without charging capacitor 1023, etc.

[0112]

[0128] The grip tiles 1030 include tile controls 1031 (e.g., enable switches or local logic controllers) for controlling when they accept power from the grip and release circuits 1020. The tile controls 1031 are disposed between the third nodes 1022c of the associated grip and release circuits 1020 and a shared node 1034 within the grip tiles 1030. In various aspects, when a grip tile 1030 is designated as part of a first or second subset of electrodes for a gripping operation (e.g., for a first grip and release circuit 1020 associated with the first subset, or a second grip and release circuit 1020 associated with the second subset), the tile controls 1031 can be selectively connected to different third nodes 1022c of different grip and release circuits 1020. In other aspects, a tile control 1031 may be selectively disconnected from an associated grip and release circuit 1020 (e.g., by opening a switch therein) when the associated grip tile 1030 is not designated as part of a subset of electrodes for a grasping operation (e.g., when the grip and release circuit 1020 is associated with n grip tiles available as a first subset of electrodes, but nm grip tiles have not been selected for grasping an object).

[0113]

[0129] An electrode pixel 1032 includes one or more electrodes that are designated to receive a voltage supplied by a connected grip and release circuit 1020 from a DC source 1010 or as a discharge from a capacitor 1023 for gripping and releasing an object. Depending on the number of electrode pixels 1032 included in a grip tile 1030, each electrode pixel 1032 may have a corresponding tile control 1031 for connecting to (or remaining disconnected from) a different grip and release circuit 1020.

[0114]

[0130] In various embodiments, a grip tile 1030 may include two or more tile controls 1031 for connecting various electrode pixels 1032 within the grip tile 1030 to a first grip and release circuit 1020 that carries a first polarity voltage, while simultaneously connecting various other electrode pixels 1032 within the grip tile 1030 to a second grip and release circuit 1020 that carries a second polarity voltage (and optionally keeping various other electrode pixels 1032 within the grip tile 1030 disconnected from any grip and release circuit 1020).

[0115]

[0131] A feedback resistor 1033 is provided to the grip tile 1030 when generating the inversion voltage and supplying current flow at the inversion voltage via the grip and release circuit 1020. Additionally, when the grip and release circuit 1020 is deactivated (e.g., powered off or set to 0 V), the feedback resistor 1033 prevents the electrode pixel 1032 from electrically floating when an adjacent electrode pixel 1032 in the array is energized. Thus, the feedback resistor 1033 reduces the risk of losing resolution on the gripping surface and the possibility of gripping (or not releasing) an unintended portion of the object.

[0116] Exemplary Control Unit

[0132] 11 illustrates a control unit according to one embodiment of the present disclosure. The control unit includes a logic controller 1110, which can be a computing device such as the computing system 1600 described in connection with FIG. 16, that controls the grip and release circuit 1020 (e.g., as described in connection with FIG. 10) to set various switching configurations to define a positive circuit 1120 (e.g., a grip and release circuit 1020 configured to deliver a positive voltage to an associated electrode pixel), a negative circuit 1130 (e.g., a grip and release circuit 1020 configured to deliver a negative voltage to an associated electrode pixel), or a neutral circuit 1140 (e.g., a grip and release circuit 1020 that does not activate or charge or discharge an associated electrode 1150 for an electrode pixel).

[0117]

[0133] The logic controller 1110 can select which of the grip-release circuits 1020 to use as the positive circuit 1120, the negative circuit 1130, or the non-actuation circuit 1140, where on the gripping surface the gripper device 110 grips the object, the gripping scheme (e.g., alternating or constant polarity), the duty cycle, the grip command, the release command, etc. based on the shape of the object to be gripped. Additionally, the logic controller 1110 may switch the polarity (or remove the applied voltage) provided to the associated electrodes 1150 by reassigning one or more grip-release circuits 1020 as the positive circuit 1120, the negative circuit 1130, or the non-actuation circuit 1140 (e.g., depending on the grip command, release command, or duty cycle). Depending on how the logic controller 1110 designates the various grip and release circuits 1020, power from the power source 750 is supplied to the associated electrode 1150 with positive polarity, negative polarity (or not supplied to the associated electrode 1150) from either the power source 750 or the charging capacitor (1023) according to the switching configuration within the individual grip and release circuit 1020.

[0118]

[0134] In addition to controlling the states of the switches in the grip and release circuit 1020, the logic controller 1110 also communicates with the gripper device 110 to ensure that objects are properly gripped and released as commanded. Various pixel sensors 1160 are associated with each electrode pixel and may include light sensors that darken when an object is gripped by the associated electrode 1150 (recording a dimming of the light when the object is gripped or an increasing light when the object is released), contact or voltage sensors that record the presence of a gripped object, distance sensors, etc. The pixel sensors 1160 may also include temperature sensors to monitor the temperature of a given electrode pixel (e.g., to control whether a heating resistor or other heating element is activated), or position sensors (e.g., integrated into the actuation motor of the gripper device 110) to monitor the relative position of the gripper device 110 within its environment.

[0119]

[0135] In various embodiments, the logic controller 1110 controls various release mechanisms 1180 associated with the electrode pixels to physically push the object off the gripper device 110, in addition to or instead of electrostatic release by the electrode pixels. In some embodiments, the logic controller 1110 activates the release mechanism 1180 in response to a release command (e.g., in parallel with the electrostatic release), in response to a pixel sensor 1160 indicating that the object is still being held by the gripper device after a threshold time has elapsed since attempting to release the object (e.g., when the electrostatic release has failed or taken longer than expected), or without electrostatically releasing the object (e.g., while maintaining the electrodes 1150 gripping the object when electrostatic release is undesirable). In various embodiments, the release mechanism 1180 can include a vent for blowing air to release the object, a plunger (e.g., controlled by a solenoid, motor, or spring) for pushing the object off the gripping surface, an additional or alternative electrode (e.g., configured to operate at a higher voltage), etc.

[0120] Exemplary Heating Elements

[0136] 12A and 12B show a layout of a heating element 1210 for use with a gripper device 110 according to an embodiment of the present disclosure.

[0121]

[0137] 12A illustrates an exemplary circuit layout for controlling a heating element 1210 embedded in a gripper device 110 according to an embodiment of the present disclosure. The heating element 1210 may include various resistive elements arranged in a known pattern on the gripping surface of the gripper device 110. A drive circuit 1240, controlled by the embedded controller 720, selectively routes power from a DC source 1250 through the heating element 1210, resistively generating heat within the heating element 1210, which is then radiated to surrounding elements of the gripper device 110.

[0122]

[0138] Various temperature sensors 1220 are located on the gripper device 110 to monitor the temperature of the gripping surface and return the measured temperature to the embedded controller 720. The computer 710 sends set temperature commands to the embedded controller 720 to adjust the desired temperature at the gripping surface and the rate at which the desired temperature is reached, which affects the drive circuitry 1240 to provide 100% on / off power supply from the DC source 1250, stepped power control from the DC source 1250, or proportional (P), integral (I), or derivative (D) control of the power from the DC source 1250, and variations thereof (e.g., P, PI, PD, or PID).

[0123]

[0139] In various embodiments, the thermal protector 1230 is a switch that is monitored by the embedded controller 720 to break contact when the temperature sensor 1220 indicates that the gripping surface has reached a threshold temperature. In some embodiments, the thermal protector 1230 includes a thermocouple that breaks contact when the bimetal reaches the threshold temperature.

[0124]

[0140] 12B illustrates an exemplary layer stack in which heating elements 1210 are embedded relative to electrode pixels 730 in gripper device 110, according to an embodiment of the present disclosure. The layer stack for the gripping surface may include various layers of electronics and electrical insulation (e.g., first circuit layer 1205a, second circuit layer 1205b, and first electrical insulation layer 1215a disposed therebetween), including various circuit and electrical elements for controlling and monitoring gripper device 110. These electronic control components are separated from the gripping and heating components by thermal insulation layer 1225, which further helps to contain heat generated by heating elements 1210 to the gripping surface and electrode pixels 730, rather than to the opposite side of gripper device 110. Although not shown, various traces or wires may pass through the insulation layers to provide power to elements on other layers or to receive return signals from these elements.

[0125]

[0141] The heating element 1210 may be disposed between a thermal insulating layer 1225 and a second electrical insulating layer 1215b, which shields the heating element 1210 from the high voltage used to control the electrode pixel 730 when gripping or releasing an object. A dielectric layer 1245 is disposed over the electrode pixel 730 to isolate the electrode pixel 730 from any gripped object 140 and to protect the electrode pixel 730 from arcing when a voltage is applied.

[0126] Exemplary Methodology

[0142] 13 is a flow diagram of a method 1300 for controlling a gripper apparatus according to an aspect of the present disclosure. Method 1300 begins at block 1310, where the logic controller 1110 of the gripper apparatus receives a gripping command to grip one or more objects. The gripping command may include one or more of the material type of the object to be gripped, a silhouette, periphery, or outline of the object, the object's initial coordinates in space, its intended final coordinates relative to the object space, its initial relative position within the pile or material selection area, and its intended final relative position. In various aspects, gripping commands for several objects may be received sequentially (e.g., a first command for a first object, a second command for a second object, etc.) and combined by the logic controller 1110 into a single gripping command (e.g., a batch command for the first object and the second object), or may be received as a single command from a control or external computer to grip the indicated objects. Additionally, the logic controller 1110 may queue various gripping commands to move obstructing or impeding objects when appropriate relative to the overall processing rate of objects in the gripper device, to increase the percentage of the gripping surface used, to manage power in the gripper device, etc.

[0127]

[0143] In block 1320, the logic controller 1110 selects electrodes for gripping the object indicated by the grip command. In various embodiments, the logic controller 1110 uses a silhouette of the object to be gripped according to the method 1400 described in connection with FIG. 14 to select the electrodes to be activated. The logic controller 1110 may adjust the position of the gripper device relative to the object to align the selected electrodes with the object to be gripped.

[0128]

[0144] In block 1330, the logic controller 1110 activates the first and second subsets of electrodes selected in block 1320 to grasp the object. In various embodiments, the logic controller 1110 selects the first and second subsets of electrodes to deliver a voltage with a first polarity and a voltage with a second polarity (opposite the first polarity) for the duration of the grasping operation (e.g., until the object is released). In some embodiments, the logic controller 1110 selects the first and second subsets of electrodes to deliver voltages of opposite polarities according to a duty cycle for the duration of the grasping operation (e.g., alternating positive / negative voltages until the object is released). The selection and application of different voltages to activate different electrodes is described in more detail in method 1500 in connection with FIG. 15 .

[0129]

[0145] Although generally described herein with reference to a first and second subset of electrodes, in various aspects, logic controller 1110 may select and control n subsets of electrodes to simultaneously grip multiple objects, but also to lift and lower various objects individually. For example, the first and second subsets of electrodes may grip a first object, while the third and fourth subsets of electrodes grip a second object, and logic controller 1110 may individually signal the paired first / second subset to lift or lower the first object and the paired third / fourth subset to lift or lower the second object. Control may also be understood to be at the level of the grip and release circuit, where grip (and release) commands set the state or mode of the grip and release circuit to be applied to the associated electrodes. Thus, images are updated at appropriate times to sequentially lift (or release) objects, which may include adding or removing given sub-images associated with various regions of the gripping surface.

[0130]

[0146] In block 1340, the logic controller 1110 determines whether the object has been grasped. In various embodiments, the logic controller 1110 receives input from various pixel sensors 1160, which may include light sensors that darken when an object is grasped by an associated electrode 1150 (recording that the light goes dark when the object is grasped), contact or voltage sensors that record the presence of a grasped object, distance sensors, etc. If the logic controller 1110 determines that the object has not been grasped, the method 1300 returns to block 1320 to reselect electrodes to grasp the object (e.g., avoid bad cells in the selected electrodes, expand or reconfigure the grip area, reconfigure the voltage used to grip the object, retry the last electrode configuration, etc.). If the logic controller 1110 determines that the object has been grasped, the method 1300 proceeds to block 1350.

[0131]

[0147] In block 1350, the logic controller 1110 moves the object from the pickup area to the drop-off area. The logic controller 1110 controls the various actuation motors 1170 in the gripper device 110 to move the gripping surface and the gripped object from one location to another.

[0132]

[0148] In block 1360, logic controller 1110 deactivates the selected first and second subsets of electrodes (activated in block 1330) to release the gripped object. In various aspects, logic controller 1110 may deactivate all electrodes simultaneously to release the object in one piece, while in other aspects logic controller 1110 may sequentially deactivate different portions of the electrodes to "peel" the object from the gripping surface (e.g., in a wave of deactivation or polarity reversals across the gripping surface).

[0133]

[0149] In various aspects, deactivating the first and second subsets includes reversing the polarity of the voltages being carried by the electrodes while grasping the object (e.g., switching the first subset from a first polarity to a second polarity and switching the second subset from a second polarity to the first polarity). Additionally or alternatively, deactivating the first and second subsets includes applying a ground or zero volt voltage to the electrodes. The selection and application of different voltages to deactivate different electrodes is described in more detail in method 1500 with reference to FIG. 15 .

[0134]

[0150] When moving multiple objects at once from the pickup area to the drop-off area, method 1300 may perform different steps in blocks 1360 and 1370 to continuously change the relative positions of the objects from the pickup area to the drop-off area (e.g., adjusting the position of gripper device 110 to adjust the positions at which the first and second objects are released relative to the positions at which the objects were lifted), to lift and drop, or stack, the multiple objects from different areas (e.g., lifting adjacent objects and layering the objects at the drop-off area).

[0135]

[0151] In block 1370, the logic controller 1110 determines whether the object has been released. In various aspects, the logic controller 1110 receives inputs from the various pixel sensors 1160 used to determine whether the object is being grasped (in block 1340) to determine whether the object remains grasped. When the logic controller 1110 determines that the object has been released (e.g., is no longer being grasped), the method 1300 may conclude, or may continue as additional objects are grasped or released. When the logic controller determines (block 1360) that the object has not been released and is still being grasped, the method 1300 proceeds to block 1380, even though the first and second subsets of electrodes have been deactivated.

[0136]

[0152] In block 1380, the logic controller 1110 activates one or more secondary release mechanisms 1180 to release the object from the gripping surface of the gripper apparatus 110. In various embodiments, the secondary release mechanisms 1180 may include vents that utilize blown air to release the object, plungers (e.g., controlled by a solenoid, motor, or spring) to push the object off the gripping surface, or electrodes in an alternative voltage transfer arrangement separate from the grip arrangement (e.g., grounding the electrodes, setting all electrodes to one polarity, setting electrodes to a polarity opposite the grip polarity at a voltage higher than the grip voltage). The method 1300 then returns to block 1370 to determine whether further action is required to release the object.

[0137]

[0153] FIG. 14 is a flow diagram of a control method for activating electrodes of a gripper device when gripping an object according to an embodiment of the present disclosure. Control software, either in the logic controller 1110 or an external computer, builds an image of the surface of the object to be gripped using progressively smaller blocks of the gripper device 110. To grasp the object, a “silhouette” of the object can be mapped to various electrodes in the gripper device 110 so that the selected electrodes at least cover the silhouette. In other words, the silhouette is used to match or associate the shape of the object with a corresponding shape region of the multiple electrodes available for gripping. Because object shapes may be irregular or matching to the shapes of the various electrodes may be imprecise, the selected electrodes may represent a larger area than the initial surface area. For example, if the surface of the object is circular, the silhouette may represent a “pixelated” circle that can contain the gripped surface within the silhouette (based on the size / shape / arrangement of the electrode pixels).

[0138]

[0154] When selecting a subset of electrode pixels, the logic controller 1110 can activate different supersets of electrode pixels hierarchically to simplify control of the gripper device. The silhouette is divided into a series of zones, tiles, and cells that correspond to the various electrodes. Thus, the logic controller 1110 uses the compressed silhouette to control the largest set of electrodes combined as a whole before using a smaller set of electrodes. Thus, the logic controller 1110 can activate all of the subunits within the selected block at a larger, higher level, thereby eliminating the need to control individual tiles when a superset of tiles can alternatively be controlled.

[0139]

[0155] Method 1400 begins at block 1410, where logic controller 1110 receives an image of an object. In various embodiments, this image is a silhouette of the surface of the object being gripped by gripper device 110, while in other embodiments, logic controller 1110 converts a two-dimensional image of the object (or one surface of the object) into a silhouette based on the size, orientation, and placement of electrode pixels associated with the gripper device.

[0140]

[0156] In block 1420, logic controller 1110 determines whether all of the gripping surfaces are used to represent the silhouette. If the silhouette uses all of the gripping surfaces, method 1400 proceeds to block 1430, where the logic controller calls all of the available pixels for the first and second subsets to grip the given object. If the silhouette does not use all of the gripping surfaces, method 1400 proceeds to block 1440.

[0141]

[0157] In block 1440, logic controller 1110 matches the highest current hierarchical level of the gripping surface to the silhouette. For example, if the gripping surface is laid out in an array of 9x8 zones, each zone in a 1x8 array of cells, each cell in a 12x1 array of tiles, each tile in a 12x1 array of pixels, and the hierarchy includes four levels (e.g., zone > cell > tile > pixel) to represent the silhouette, logic controller 1110 attempts to match first entire zones, then entire cells, entire tiles, and finally individual pixels to the silhouette. As will be appreciated, logic controller 1110 can represent silhouettes using more or fewer hierarchical levels than four, and the hierarchical levels can have array sizes / shapes different from those given in the above example.

[0142]

[0158] In block 1450, logic controller 1110 determines whether the silhouette covers the object. If the silhouette does not cover all of the object, method 1400 proceeds to block 1460, where logic controller 1110 selects the next lower hierarchical level and returns to block 1440 to attempt to match the next lower hierarchical level.

[0143]

[0159] In various aspects, logic controller 1110 can match various hierarchical levels to the silhouette so that a superset is not invoked (down to the lowest level) if the surface does not completely cover the corresponding electrode. For example, when a surface partially covers a first zone (at the highest hierarchical level), logic controller 1110 does not match the first hierarchical level to the surface, but waits to use lower hierarchical levels within the first zone to represent the silhouette. Once logic controller 1110 reaches the lowest hierarchical level (e.g., pixel), logic controller 1110 begins matching silhouettes beyond the initial contour of the object's surface. Similarly, logic controller 1110 can use image files defining silhouettes in various formats that can be decomposed into smaller sub-images to form a mosaic representing a subsection of the image. In other words, an image of a "whole pad" layout can be decomposed into a series of smaller images that can be handled by appropriate zones of the surface, or several sub-images that can be combined to form the "whole pad" layout.

[0144]

[0160] When the silhouette covers all of the surface (or extends beyond the surface), method 1400 proceeds to block 1440. In block 1470, logic controller 1110 writes image instructions to individual electrodes of the selected hierarchical level. In various aspects, the selected hierarchical level is divided into two subsets of electrodes across the hierarchical array, with a first subset carrying a voltage with a first polarity and a second subset carrying a voltage with a second (opposite) polarity, to electrostatically grip the object according to the object's silhouette.

[0145]

[0161] When multiple objects are to be grasped simultaneously, method 1400 may be repeated, and any electrodes excluded from the first and second subsets of electrodes for the previously laid out object (e.g., based on the shape and position of the first object to be grasped via the first and second subsets of electrodes) may be available for use in grasping the second (i.e., subsequent) object. In various aspects, when multiple objects are to be grasped at once, at least one buffer of pixels is established around each of the currently placed objects before logic controller 1110 attempts to grasp the subsequent object simultaneously with the previously laid out object. These buffer pixels may be defined around the boundaries of the various silhouettes and may also be shared by multiple silhouettes as a third subset of pixels that remains deactivated when grasping the various objects.

[0146]

[0162] 15 is a flow diagram of a method 1500 for controlling a switching unit according to an embodiment of the present disclosure. Method 1500 begins at block 1510, where logic controller 1110 opens and closes various switches in the switching unit (such as switches 1021 of switching unit 1000 described in connection with FIG. 10) according to an initial assignment of a first polarity to a first subset of electrodes and a second polarity to a second subset of electrodes. In various embodiments, each subset of electrodes includes a switch that allows it to receive current (or not receive current) with a first polarity or a second polarity, and one or more electrode pixels that are energized by an associated circuit. The various pixels may be arranged such that each electrode in the first subset is adjacent to at least one electrode in the second subset (and vice versa).

[0147]

[0163] In block 1520, the logic controller 1110 charges the capacitors 1023 of the switching units 1000 while supplying the initial polarity voltages to the associated electrodes. The capacitors 1023 associated with a first subset of electrodes are charged while the first subset is activated to carry a voltage with a first polarity, and the capacitors 1023 associated with a second subset of electrodes are charged while the second subset of electrodes is activated to carry a voltage with a second polarity.

[0148]

[0164] In block 1530, the logic controller 1110 opens and closes various switches 1021 of the switching unit 1000 to reverse the initially selected polarity. Thus, when a first subset of electrodes was activated to convey a first polarity in block 1510, the first subset of electrodes is activated to convey a second polarity in block 1530. Similarly, when a second subset of electrodes was activated to convey a second polarity in block 1510, the second subset of electrodes is activated to convey the first polarity in block 1530. In various aspects, the logic controller 1110 disconnects the switching unit from the power source used to supply current according to the initial polarity (in block 1510) and opens and closes the switches 1021 to charge the capacitor 1023 and use the capacitor 1023 as the power source for the electrode pixel (in block 1520).

[0149]

[0165] In various aspects, the logic controller 1110 determines to proceed with the method 1500 to block 1530 in response to a release command (e.g., the object stops being gripped), a duty cycle timer (e.g., at least X milliseconds (ms) have elapsed since block 1510), a voltage or current measurement of the gripped object (e.g., the gripped object draws at least Y milliamperes (mA) of current), etc.

[0150]

[0166] In block 1540, the logic controller 1110 discharges the capacitor 1023 that was charged in block 1520. The switch 1021 of the associated switching unit 1000 is configured to provide power from the capacitor 1023 with a polarity opposite to that initially provided by the power source, so that Electrodes that conduct a voltage with a first polarity in block 1510 conduct a voltage with a second polarity in block 1540. Similarly, electrodes that conduct a voltage with a second polarity in block 1510 conduct a voltage with a first polarity in block 1540. Any electrodes not selected by logic controller 1110 to conduct a voltage in block 1510 (e.g., non-actuated electrodes) remain in a non-actuated state in block 1540.

[0151]

[0167] In various embodiments, the logic controller 1110 can apply a constant initial polarity through a selected subset of electrodes (at block 1510) while grasping the object and apply an opposite polarity (at block 1540) to release the object. In some embodiments, the logic controller 1110 alternates between the initial and opposite polarities according to a duty cycle (at blocks 1510-1540) while grasping the object, and releases the object by removing or no longer applying voltage to the electrodes (at block 1560).

[0152]

[0168] In some embodiments, the duty cycle defines the length of time the first and second polarities are applied and when the polarities of the corresponding electrodes are reversed. In various aspects, the duty cycle may cycle through the opposite polarities every X milliseconds (ms) or when the gripped object begins to conduct a threshold amount of current of Y milliamperes (mA). The logic controller 1110 may set the value of X or Y based on the material of the gripped object, the thickness or weight of the gripped object, the frequency of the AC power source (e.g., 60 Hertz (Hz), 50 Hz, Z Hz), the capacitive and inductive characteristics of the gripper device, etc. For example, a duty cycle that switches various electrode pixels on and off every 10 ms to 18 ms may be used when gripping carbon fiber ply. In various aspects, the duty cycle may be uniform (e.g., a 50% duty cycle with Xms in initial polarity and Xms in reverse polarity), non-uniform (e.g., Xms in initial polarity and 2Xms or 0.5Xms in reverse polarity), or time-varying (e.g., Xms in initial polarity, Xms in reverse polarity, followed by 2Xms in initial polarity and 2Xms in reverse polarity, etc.).

[0153]

[0169] By using a certain polarity scheme, polarity reversal can aid in the removal of an object from the gripper device 110 due to the charge applied to the object from the electrodes. For example, a portion of an object gripped by a positive polarity electrode may begin to experience a negative polarity in the object's material matrix (at least at the surface level), aiding in gripping the object. This negative polarity induced in the object is then repelled when the electrodes are switched to a negative polarity, thereby aiding in the release of the object. However, manufacturers may wish to avoid inducing a charge in portions of the object being gripped and may specify a duty cycle for switching between positive and negative polarity, thereby avoiding charging the object or reducing the amount of charge applied to the object when gripped.

[0154]

[0170] Additionally or alternatively, when the logic controller 1110 receives a command to drop all currently grasped objects, the logic controller 1110 can drive all electrodes to the same polarity (e.g., all positive or all negative) for a short period of time (e.g., X ms) to aid in the release of the material. In another aspect, the logic controller 1110 can continue to drive the electrodes at the assigned duty cycle, but reduce the voltage applied to the electrodes below the electroadhesion threshold for the grasped material. Thus, reducing the voltage and continuing the cycle can allow the portion of the pads whose voltage is reduced to release all grasped objects while reducing the accumulated charge in the objects and pads.

[0155]

[0171] Thus, in block 1550, logic controller 1110 determines whether the object is gripped by the duty cycle and whether to continue based on the duty cycle. If logic controller 1110 determines to continue based on the duty cycle, method 1500 returns to block 1510 as logic controller 1110 applies the initial polarity voltage to the electrodes. If logic controller 1110 determines not to continue based on the duty cycle, method 1500 proceeds to block 1560 to release the object when using an alternating polarity gripping scheme or when using a constant polarity gripping scheme (e.g., no duty cycle) that released the object at blocks 1530-1540. In various aspects, based on the length and time of the duty cycle required to move the object, logic controller 1110 may convert the final cycle of the duty cycle to a constant polarity scheme, hold the object gripped according to the initial polarity assignment until a release command is received, and responsively switch to the opposite polarity to release the object.

[0156]

[0172] In block 1560, the logic controller 1110 opens and closes the various switches 1021 of the switching unit 1000 to remove the voltage from the electrodes. In various aspects, the logic controller 1110 may continue to discharge any remaining charge on the capacitor 1023 (e.g., via a bleed-off resistor), but does not instruct the capacitor 1023 to power the electrodes. The method 1500 may then end.

[0157] Exemplary Processing System and Controller

[0173] FIG. 16 illustrates a schematic diagram of a computing system 1600 that can be used with the systems and methods described herein. The computing system 1600 includes a processor 1660 (e.g., a central processing unit (CPU)) in data communication with a memory 1650, an input device 1670, and an output device 1680. It should be understood that the functional blocks described with respect to the computing system 1600, although illustrated separately, are not required to be separate functional elements. For example, the processor 1660 and the memory 1650 can be embodied on a single chip. The processor 1660 can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any suitable combination thereof, designed to perform the functions described herein. A processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP, or any other similar configuration.

[0158]

[0174] The processor 1660 can be coupled via one or more buses to read and write information to the memory 1650. The processor may additionally or alternatively include memory such as processor registers. The memory 1650 may include a processor cache, including multiple levels of hierarchical caches, with different levels having different capacities and access speeds. The memory 1650 may also include random access memory (RAM), other volatile storage devices, or non-volatile storage devices. The storage devices may include hard drives, flash memory, etc. The memory 1650 may also include computer program products embodied thereon, including code such as a motion system control application 1656 used to control the position and orientation of pixelated pads, as described in connection with FIGS. 2 and 6A-6B, a voltage control application 1654 used to control voltage inputs, as described in connection with FIGS. 3B and 4, or a heating control application 1658 used to control voltage or power to a heating element, as described in connection with FIG. 3B. The control applications 1654, 1656, and 1658 may be code executable by the processor 1660. In various examples, memory is referred to as a computer-readable medium or a non-transitory computer-readable medium. A computer-readable storage medium is a non-transitory device capable of storing information and may be distinguished from a computer-readable transmission medium, such as a transient electronic signal, that can convey information from one place to another. The non-transitory computer-readable medium includes computer-executable instructions that, when executed by a processing system, cause the processing system to perform a method including gripping an object via a substrate including a plurality of electrode pixels and selectively energizing each electrode pixel of the plurality of electrode pixels via a controller, as described in connection with FIGS. 2 and 3A-6B. In some embodiments, the method performed by the processing system includes determining a shape of the object and energizing a subset of the plurality of electrode pixels via a controller based on the shape of the object.In some embodiments, the method performed by the processing system includes positioning the substrate proximate to the object via a motion system. In some embodiments, the method performed by the processing system includes positioning the substrate based on a distance measurement between the substrate and the object. In some embodiments, the method performed by the processing system includes energizing at least one heating element configured to heat the substrate via a controller. Computer-readable media as described herein may generally refer to computer-readable storage media or computer-readable transmission media.

[0159]

[0175] Processor 1660 may also be coupled to input device(s) 1670 and output device(s) 1680 for receiving input from and providing output to computing system 1600. Input device 1670 may be part of distance measurement system 208 or substrate temperature sensor 1678. Suitable input devices from distance measurement system 208 include, but are not limited to, a video camera, encoder (e.g., optical or magnetic, capacitive or inductive encoder), resolver, electrometer, angle sensor, accelerometer, gyroscope, inertial measurement unit, global positioning system (GPS), motion detector, etc., which may be coupled to a pixelated pad (e.g., pixelated pad 202 of FIG. 2 ) or video processing software for detecting the position of an object grasped by the pixelated pad. For example, input device 1670 may include an encoder or a position sensor, such as an angular position sensor, as described in connection with FIG. 2 . The substrate temperature sensor 1678 may be at least one of a thermocouple, a resistance temperature detector, a thermistor, or a semiconductor-based integrated circuit. Suitable output devices include, but are not limited to, the motion system 206 described in connection with Figures 2 and 6A-6B, the plurality of electrode pixels 212 described in connection with Figures 2 and 3A-6B, and the heating element 328 described in connection with Figure 3.

[0160]

[0176] Aspects of the present disclosure have been described above with reference to particular embodiments. However, those skilled in the art will understand that various modifications and changes may be made thereto without departing from the broader spirit and scope of the present disclosure as defined in the appended claims. Accordingly, the foregoing description and drawings should be regarded as illustrative rather than restrictive.

[0161] Example clauses

[0177] Example implementations are described in the numbered clauses below.

[0162]

[0178] Clause 1. A control unit comprising: a voltage converter configured to boost an input voltage relative to an output voltage; a first gripping circuit configured to selectively supply an output voltage at a first polarity to a first electrode subset of a plurality of electrodes; a second gripping circuit configured to selectively supply an output voltage at a second polarity opposite the first polarity to a second electrode subset of the plurality of electrodes different from the first electrode subset, associated with the first electrode subset; a first release circuit configured to selectively invert the output voltage supplied to the first electrode subset to the second polarity; and a second release circuit configured to selectively invert the output voltage supplied to the second electrode subset to the first polarity.

[0163]

[0179] Clause 2. The control unit described in Clause 1, wherein each of the first grip circuit and the first release circuit further comprises a first switch connected between the voltage converter and the first node, a capacitor connected between the first node and a second node, a second switch connected between the second node and an electrode control node for the first subset of electrodes, a third switch connected between the second node and ground, a fourth switch connected between the first node and ground, and a fifth switch connected between the first node and the electrode control node.

[0164]

[0180] Clause 3. When the first gripping circuit and the first release circuit provide an output voltage at a first polarity to the first electrode subset, The first switch, the third switch, and the fifth switch are opened, and the second switch and the fourth switch are closed. The control unit of clause 2, configured to close the first switch, the third switch, and the fifth switch and open the second switch and the fourth switch when supplying an output voltage with a second polarity to the first electrode subset.

[0165]

[0181] Clause 4. A control unit described in any one of clauses 1 to 3, wherein the first subset of electrodes comprises an enable switch connected between the electrode control node and a third node, and at least one electrode pixel of a predetermined shape and position among the plurality of electrodes.

[0166]

[0182] Clause 5. A control unit described in any one of clauses 1 to 4, further comprising a processor configured to identify, based on the shape and position of an object to be grasped via the first subset of electrodes and the second subset of electrodes, which electrodes of the plurality of electrodes are included in the first subset of electrodes or the second subset of electrodes, and which electrodes of the plurality of electrodes are excluded from both the first subset of electrodes and the second subset of electrodes.

[0167]

[0183] Clause 6. An apparatus comprising: a gripper device configured to electrostatically grip an object via a plurality of electrodes; and a control unit configured to instruct the gripper device to grip the object by selecting individual electrodes of the plurality of electrodes to grip the object, actuating a first subset of the electrodes to deliver a voltage at a first duty cycle, actuating a second subset of the individual electrodes to deliver a voltage at a second duty cycle different from the first duty cycle, and to release the object from the gripper device by energizing the first subset of electrodes according to a third duty cycle different from the first duty cycle, and energizing the second subset of electrodes according to a fourth duty cycle different from the second duty cycle.

[0168]

[0184] Clause 7. The device described in Clause 6, wherein the first duty cycle and the fourth duty cycle always apply a voltage according to a first polarity, and the second duty cycle and the fourth duty cycle always apply a voltage according to a second polarity opposite to the first polarity.

[0169]

[0185] Clause 8. An apparatus as described in clause 6 or 7, wherein the control unit reverses the first polarity to a second polarity when releasing the object by charging a first capacitor associated with the first subset while the first subset is activated to conduct voltage at the first polarity, and discharging the first capacitor to the first subset at the second polarity in response to disconnection of the voltage supply from the first subset.

[0170]

[0186] Clause 9. An apparatus described in any one of clauses 6 to 8, wherein the first duty cycle and the second duty cycle constantly cycle between a first polarity and a second polarity opposite to the first polarity at an equal cycle frequency, and the third duty cycle and the fourth duty cycle constantly apply a ground voltage to the first subset and the second subset of electrodes.

[0171]

[0187] Clause 10. The apparatus of any one of clauses 6 to 9, wherein cycling between the first polarity and the second polarity further includes charging a first capacitor associated with the first subset while the first subset is activated to carry a voltage at the first polarity during a first half of the equal-cycle frequency, charging a second capacitor associated with the second subset while the second subset is activated to carry a voltage at the second polarity during the first half of the equal-cycle frequency, discharging the first capacitor while the first subset is activated to carry a voltage at the second polarity during a second half of the equal-cycle frequency, and discharging the second capacitor while the second subset is activated to carry a voltage at the first polarity during the second half of the equal-cycle frequency.

[0172]

[0188] Clause 11. The device of any one of clauses 6 to 10, wherein the control unit is further configured to verify via the optical sensor that the object is electrostatically held by the gripper device in response to activating the first subset and the second subset of electrodes, and the control unit is further configured to activate a solenoid release mechanism included in the gripper device in response to determining via the optical sensor that the object is still held by the gripper device after applying voltage according to the third duty cycle and the fourth duty cycle.

[0173]

[0189] Clause 12. A device described in any one of clauses 6 to 11, wherein each electrode of the first subset is adjacent to at least one electrode of the second subset, and each electrode of the second subset is adjacent to at least one electrode of the first subset.

[0174]

[0190] Clause 13. A method comprising: in response to receiving a first command to grip an object via a gripper device having a plurality of electrodes, identifying at least two electrodes of a plurality of electrodes associated with the object; actuating the at least two identified electrodes, a first subset of the at least two electrodes to deliver a voltage with a first polarity and a second subset of the at least two electrodes to deliver a voltage with a second polarity opposite the first polarity; and in response to receiving a second command to release the object from the gripper device, reversing the polarity of the voltage of the first subset and the second subset.

[0175]

[0191] Clause 14. The method of clause 13, further comprising verifying via the optical sensor that the object is electrostatically held to the gripper device in response to actuating the at least two identified electrodes.

[0176]

[0192] Clause 15. The method of clause 13 or 14, further comprising actuating a solenoid release mechanism included in the gripper device in response to receiving a second command to release the object from the gripper device.

[0177]

[0193] Clause 16. The method of any one of clauses 13 to 15, further comprising verifying via the optical sensor that the object is no longer electrostatically held by the gripper device after reversing the first polarity of the voltage, and wherein in response to determining that the object is still held by the gripper device, a solenoid release mechanism is activated.

[0178]

[0194] Clause 17. The method of any one of clauses 13 to 16, wherein each electrode of the plurality of electrodes is an individually controllable electrode pixel, and the plurality of electrodes is arranged in a grid pattern with adjacent electrode pixels configured to operate relative to each other with alternating voltage polarities.

[0179]

[0195] Clause 18. The method of any one of clauses 13 to 17, wherein reversing the polarity of the voltage in the first subset and the second subset further comprises: charging a first capacitor associated with the first subset while the first subset carries a voltage with the first polarity; charging a second capacitor associated with the second subset while the second subset carries a voltage with the second polarity; discharging the first capacitor to the first subset with the second polarity in response to disconnecting the voltage supply from the first subset; and discharging the second capacitor to the second subset with the first polarity in response to disconnecting the voltage supply from the second subset.

[0180]

[0196] Clause 19. The method of any one of clauses 13 to 17, wherein identifying at least two electrodes of the plurality of electrodes to associate with the object further includes receiving an image of the shape of the object, receiving a location of the object within the pickup area, and matching the shape to a corresponding shape area of ​​the plurality of electrodes, the corresponding shape area being disposed within the plurality of electrodes such that it corresponds to the location of the object within the pickup area when the gripper device is disposed in the pickup area.

[0181]

[0197] Clause 20. The method of any one of clauses 13 to 19, wherein activating at least two electrodes comprises heating at least two identified electrodes to a predetermined temperature range.

[0182] Further considerations

[0198] The foregoing description is provided to enable any person skilled in the art to practice the various embodiments described herein. The examples described herein are not limited in scope, applicability, or embodiments set forth in the claims. Various modifications to these embodiments will be readily apparent to those skilled in the art. Additionally, the general principles defined herein may be applied to other embodiments. For example, changes may be made in the function and arrangement of described elements without departing from the scope of the present disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described for some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of aspects set forth herein. Furthermore, the scope of the present disclosure is intended to cover apparatuses or methods that are implemented using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

[0183]

[0199] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects.

[0184]

[0200] "At least one" of a list of items, as used herein, refers to any combination of those items, including single members. By way of example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other permutation of a, b, and c).

[0185]

[0201] As used herein, the term "identifying" encompasses a wide variety of actions. For example, "identifying" can include calculating, computing, processing, deriving, examining, looking up (e.g., looking up in a table, database, or other data structure), ascertaining, etc. Also, "identifying" can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), etc. Also, "identifying" can include resolving, selecting, choosing, establishing, etc.

[0186]

[0202] The methods disclosed herein include one or more steps or actions to achieve the method. Method steps and / or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions may be modified without departing from the scope of the claims. Furthermore, various steps of the methods described above may be performed by any suitable means capable of performing the corresponding functions. This means may include various hardware and / or software components and / or modules, including, but not limited to, circuits, application-specific integrated circuits (ASICs), or processors. Generally, where steps are illustrated in figures, these steps may have corresponding equivalent means-plus-function components that are similarly numbered.

[0187]

[0203] The following claims are not intended to be limited to the embodiments set forth herein, but are to be accorded the full scope consistent with the language of the claims. Within the claims, reference to an element in the singular does not mean "one and only one," but rather "one or more," unless otherwise specified. The term "some" means one or more, unless otherwise specified. A claim will not be construed as falling within 35 U.S.C. § 112(f) unless it is expressly recited using the phrase "means for," or, in the case of a method claim, the phrase "step for." Structural and functional equivalents to the elements of various aspects described throughout this disclosure that are known, or later become known, to those skilled in the art are expressly incorporated herein by reference and intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be made available to the public, regardless of whether such disclosure is expressly recited in the claims.

Claims

1. a gripper device (110) configured to electrostatically grip an object (140) via a plurality of electrodes (1150); Logic controller (1110) Equipped with The logic controller (1110) Commanding (1310) the gripper device to grip the object, selecting (1320) individual electrodes of the plurality of electrodes for grasping the object; activating a first subset of the individual electrodes to deliver a voltage at a first duty cycle (1330); actuating a second subset of the individual electrodes to deliver the voltage at a second duty cycle different from the first duty cycle; commanding (1310) to grasp the object by Releasing the object from the gripper device, applying the voltage to the first subset of the individual electrodes according to a third duty cycle different from the first duty cycle; applying the voltage to the second subset of the individual electrodes according to a fourth duty cycle different from the second duty cycle; Releasing the object by configured to: Device.

2. 2. The apparatus of claim 1, wherein the first duty cycle and the fourth duty cycle always apply the voltage according to a first polarity, and the second duty cycle and the fourth duty cycle always apply the voltage according to a second polarity opposite the first polarity.

3. When releasing the object, the logic controller: charging (1520) a first capacitor (1023) associated with the first subset while the first subset is activated to deliver the voltage in the first polarity; and in response to disconnecting the voltage supply from the first subset, discharging (1540) the first capacitors into the first subset with the second polarity. The apparatus of claim 2 , further comprising: inverting the first polarity to the second polarity in the first subset.

4. 2. The apparatus of claim 1, wherein the first duty cycle and the second duty cycle constantly cycle between a first polarity and a second polarity opposite the first polarity at an equal cycle frequency, and the third duty cycle and the fourth duty cycle constantly apply a ground voltage to the first and second subsets of the individual electrodes.

5. Cycling between the first polarity and the second polarity comprises: charging (1520) a first capacitor (1023) associated with the first subset while the first subset is activated to deliver the voltage at the first polarity during the first half of the isocyclic frequency; charging a second capacitor associated with the second subset while the second subset is activated to deliver the voltage at the second polarity during the first half of the isocyclic frequency; Discharging the first capacitor during the second half of the iso-cycle frequency while the first subset is activated to deliver the voltage at the second polarity; and discharging the second capacitor during the second half of the iso-cycle frequency while the second subset is activated to deliver the voltage at the first polarity. The apparatus of claim 4 further comprising:

6. 13. The apparatus of claim 1, wherein the logic controller is further configured to verify (1340) via an optical sensor that the object is electrostatically held to the gripper device in response to activating the first and second subsets of individual electrodes, and wherein the logic controller is further configured to activate (1380) a solenoid release mechanism included in the gripper device in response to determining (1370) via the optical sensor that the object is still held to the gripper device after applying the voltage according to a third duty cycle and a fourth duty cycle.

7. 2. The apparatus of claim 1, wherein each electrode in the first subset is adjacent to at least one electrode in the second subset, and each electrode in the second subset is adjacent to at least one electrode in the first subset.

8. In response to receiving (1310) a first command to grip an object (140) via a gripper device (110) comprising a plurality of electrodes (1150), selecting 1320 at least two electrodes of the plurality of electrodes associated with the object; activating (1330) the at least two electrodes, with a first subset of the at least two electrodes to deliver a voltage with a first polarity and a second subset of the at least two electrodes to deliver the voltage with a second polarity opposite the first polarity; reversing (1360) the polarity of the voltages of the first subset and the second subset in response to receiving a second command to release the object from the gripper device; A method comprising:

9. 10. The method of claim 8, further comprising verifying (1340) that the object is electrostatically held to the gripper device via an optical sensor in response to actuating the at least two electrodes.

10. in response to receiving the second command to release the object from the gripper device; The method of claim 8 or 9, further comprising actuating (1380) a solenoid release mechanism included in the gripper device.

11. 11. The method of claim 10, further comprising verifying (1370) that the object is no longer electrostatically held by the gripper device via an optical sensor after reversing the first polarity of the voltage, and wherein the solenoid release mechanism is actuated in response to determining that the object is still held by the gripper device.

12. 9. The method of claim 8, wherein each electrode of the plurality of electrodes is an individually controllable electrode pixel (1032), and the plurality of electrodes are arranged in a grid pattern with adjacent electrode pixels configured to operate relative to each other with alternating voltage polarities.

13. Reversing the polarity of the voltages in the first subset and the second subset includes: charging (1520) a first capacitor (1023) associated with said first subset while said first subset carries said voltage at said first polarity; charging a second capacitor associated with the second subset while the second subset carries the voltage at the second polarity; Discharging (1540) the first capacitors into the first subset with the second polarity in response to disconnecting (1530) the voltage supply (1010) from the first subset; discharging the second capacitors into the second subset with the first polarity in response to disconnecting the voltage supply from the second subset; The method of claim 8 further comprising:

14. Selecting the at least two electrodes of the plurality of electrodes to associate with the object includes: receiving 1410 an image of the shape of the object; receiving a location of the object within a pickup area (120); Matching (1440) the shape to a corresponding shape region of the plurality of electrodes, the corresponding shape region being positioned within the plurality of electrodes to correspond to the location of the object within the pickup area when the gripper device is positioned within the pickup area; The method of claim 8 further comprising:

15. The method of claim 8 , wherein activating the at least two electrodes comprises heating the at least two electrodes to a predetermined temperature range.

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