Electroadhesive device for handling flexible articles

Abstract

An electroadhesive device (100) for handling a flexible article comprises a gripping surface (110) for picking up the flexible article, a plurality of electrodes (120, 130) located inside the gripping surface (110), and a dielectric material (140) located between the electrodes (120, 130); a voltage difference between adjacent electrodes (120, 130) generates an electrical adhesion force causing the flexible article to adhere to the gripping surface (110); the gripping surface (110) comprises a curved surface; the electroadhesive device (100) is rollable on the flexible article, or rotatable about an axis of rotation such that at least a portion of the flexible article may be wound on the curved surface.

Description

Technical Field

[0001] The present disclosure relates to electroadhesion devices and systems for manipulating flexible articles, and methods for transporting flexible articles. Background Art

[0002] The textile industry is one of the world's largest manufacturing sectors. Despite its enormous market, it remains labor-intensive. Due to the complexity of fabric manipulation during production, the transition to full automation has been slow. Consequently, the industry suffers from high factory costs.

[0003] Conventional robotic grippers typically use suction or actuator-driven mechanical grippers to pick up and move items. However, these grippers are not well suited for handling flexible items. Fabric manipulation is challenging due to its high degree of flexibility. Using conventional grippers, it is difficult to individually pick up thin, flexible fabrics from a stack. In particular, conventional grippers can cause wrinkling and folding of the fabric and can damage it when attempting to precisely position it on the work surface.

[0004] Electroadhesion is an electrically controllable adhesion mechanism that has been studied and applied in a variety of applications. Electroadhesion involves the use of electrostatic forces to join two objects. Electroadhesion exploits the electrical control of these forces to allow for a temporary and removable attachment between two objects. This electrostatic adhesion, generated by an applied electric field, holds two surfaces together or increases the effective traction or friction between them. Compared to other existing adhesion solutions, electroadhesion offers greater adaptability, reduced system complexity, lower energy consumption, and less damage to materials.

[0005] Recently, electroadhesion-based gripping systems have been developed for manipulating flexible objects. Most systems use a generally flat electroadhesion pad to pick up the flexible object. To avoid wrinkling and folding on the flexible object, the size of the flat electroadhesion pad needs to match the size of the flexible object. Therefore, to handle large flexible objects, manufacturers may need to build at least one electroadhesion-based gripping system of the same size, which can be very expensive.

[0006] Therefore, there is a need to provide an alternative and improved method of handling flexible items that allows for the automated picking, moving and positioning of thin and fragile items without causing unnecessary marks and damage to the items. Summary of the Invention

[0007] This disclosure provides a novel electroadhesive gripping device and system for manipulating flexible objects, resolving the aforementioned issues with conventional systems. The gripping system significantly reduces size and cost, and the gripping force is controllable, ensuring that flexible objects do not fall during manipulation.

[0008] In a first aspect, an electroadhesion device for manipulating a flexible object is provided. The electroadhesion device may include a gripping surface for picking up the flexible object, a plurality of electrodes on the inner side of the gripping surface, and a dielectric material positioned between the electrodes. A voltage difference between adjacent electrodes may generate an electroadhesion force, causing the flexible object to adhere to the gripping surface. The gripping surface may include a curved surface. The electroadhesion device may be capable of rolling on the flexible object or rotating about a rotation axis such that at least a portion of the flexible object can be wrapped around the curved surface.

[0009] In certain embodiments, the electroadhesion device may be in the form of a roller, and the gripping surface may have a substantially circular cross-section. The plurality of electrodes may include positive and negative electrodes embedded in a dielectric material in an alternating manner. The electroadhesion device may include a protective layer surrounding the positive and negative electrodes and the dielectric material. Alternatively, the gripping surface may include a substantially flat portion that smoothly transitions to a curved surface. The substantially flat portion may be configured to contact the flexible article prior to the curved surface.

[0010] In some embodiments, at least a portion of the electroadhesion device can be deformable to increase the initial contact area between the gripping surface and the flexible article. The electrodes can be removably mounted to the electroadhesion device. The gripping surface can be roughened to increase friction when the electroadhesion device rolls over the flexible article.

[0011] In a second aspect, an electroadhesion system for conveying flexible articles is provided. The electroadhesion system may include a first gripper, a second gripper, a voltage source for applying a voltage to electrodes in the first gripper and the second gripper, a drive system for actuating the first gripper and the second gripper, and a controller for controlling operation of the first gripper and the second gripper, wherein the first gripper includes at least one electroadhesion device and the second gripper includes at least one electroadhesion device.

[0012] In some embodiments, the first gripper may include a first electroadhesion roller, and the second gripper may include a second electroadhesion roller. The first electroadhesion roller and the second electroadhesion roller may be oriented parallel to each other and controlled separately. The first electroadhesion roller may be controlled to roll in one direction to pick up one edge of the flexible item. The second electroadhesion roller may be controlled to roll in the opposite direction to pick up the opposite edge of the flexible item. The first electroadhesion roller and the second electroadhesion roller may each include a sensor for detecting the area of ​​wrapping of the edge of the flexible item on the gripping surface.

[0013] In certain embodiments, the controller may include a scroll control unit configured to control the scroll distance or rotation angle of the first and second electroadhesion rollers based on an operating parameter selected from the group consisting of: the number of electrodes in the first and second electroadhesion rollers, the dimensions of the first and second electroadhesion rollers, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the coefficient of friction of the flexible article. The controller may also include a voltage control unit configured to control the voltage applied to the electrodes based on the properties of the flexible article and parameters of the first and second electroadhesion rollers. The controller may also include an edge detection unit configured to detect the position of an edge of the flexible article and assist in aligning the first and second electroadhesion rollers with the edge of the flexible article.

[0014] In a third aspect, a method for conveying a flexible article is provided. The method may include: placing a first gripper in contact with a first edge of the flexible article; applying a first voltage to an electrode in the first gripper to establish electrical adhesion between the first gripper and the first edge; rolling the first gripper in a first direction so that a first portion of the flexible article proximate the first edge wraps around the first gripper; placing a second gripper in contact with a second edge of the flexible article; applying a second voltage to an electrode in the second gripper to establish electrical adhesion between the second gripper and the second edge; rolling the second gripper in a second direction opposite to the first direction so that a second portion of the flexible article proximate the second edge wraps around the second gripper; and moving the first gripper and the second gripper to a target position.

[0015] In certain embodiments, rotational movement of the first and second electroadhesion rollers is disabled while the first and second electroadhesion rollers are moving toward a target location.

[0016] In some embodiments, the first electroadhesion roller can be driven to roll a first distance on the flexible article. The second electroadhesion roller can be driven to roll a second distance on the flexible article. The first distance and the second distance can be determined based on operating parameters selected from the group consisting of: the number of electrodes in the first and second electroadhesion rollers, the dimensions of the first and second electroadhesion rollers, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the coefficient of friction of the flexible article.

[0017] In some embodiments, the method may include aligning the longitudinal axes of the first and second electroadhesion rollers with the first and second edges of the flexible article, respectively. The alignment may be assisted by an edge detection unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects and features of the present invention will become apparent from the following description of the present invention when taken in conjunction with the accompanying drawings, in which:

[0019] Figure 1 A cross-sectional view of an electroadhesion device according to one embodiment of the present disclosure is shown.

[0020] Figure 2A and Figure 2B The operation of an electroadhesion roller according to one embodiment of the present disclosure is illustrated.

[0021] Figure 3A and Figure 3B The operation of the electroadhesion roller according to another embodiment of the present disclosure is illustrated.

[0022] Figure 4 A functional block diagram of an electroadhesion system for conveying flexible articles according to one embodiment of the present disclosure is shown.

[0023] Figure 5 The arrangement of the first gripper and the second gripper in the electroadhesion system is shown.

[0024] Figure 6 The state is shown when the electroadhesion roller has picked up a flexible item.

[0025] Figure 7 A flow chart of a method for conveying a flexible article according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0026] The present disclosure generally relates to an electroadhesion device, system, and method for transporting flexible articles. Figure 1 1 shows a cross section of an exemplary electroadhesion device. The electroadhesion device 100 includes a gripping surface 110 for picking up flexible items and a plurality of electrodes 120, 130 located inside the gripping surface 110. For illustrative purposes, the electroadhesion device 100 has a total of six pairs of 12 electrodes. Each pair has a positive electrode 120 and a negative electrode 130. It will be readily understood that more or fewer electrodes may be used in a given electroadhesion device. In some embodiments, the positive and negative electrodes are embedded in a dielectric material 140 in an alternating manner on the inside of the gripping surface 110. As shown in FIG. Figure 1 As shown in FIG, electrodes 120, 130 are arranged circumferentially on the inside of the gripping surface 110. Adjacent electrodes 120, 130 are separated by a dielectric material 140. The gap between adjacent electrodes 120, 130 can be selected based on the needs of a particular application.

[0027] When the electroadhesion device 100 is placed against or near the surface of a flexible object, an electrostatic adhesion voltage can be applied to the electrodes. The electrostatic adhesion voltage generates positive and negative charges on adjacent electrodes, which creates an electric field. An electrostatic adhesion voltage is a voltage that produces an appropriate electrostatic force to connect adjacent surfaces. The electrode pairs 120 and 130 form closely spaced electrical conductors that generate an alternating pattern of induced currents. The electrode pairs 120 and 130 are embedded in a dielectric material 140 so that the electric field between each electrode pair induces an electric charge in the dielectric material. This increase in the electric field leads to an increase in charge density. When the electroadhesion device 100 comes into contact with the flexible object, the same electric field generates opposite charges on the surface of the flexible object. Due to the opposite charges, an attractive force is generated between them. As a result, the flexible object adheres to the gripping surface 110 of the electroadhesion device 100.

[0028] The voltage required for electroadhesion device 100 varies depending on various factors, including the area of ​​the gripping surface, the conductivity of the material, the gap between the electrode pair, the dielectric material, the surface material of the flexible article, and operating environmental conditions, including temperature and humidity. In one embodiment, the electrostatic adhesion voltage comprises a differential voltage between electrode pair 120, 130 ranging from approximately 100 volts to approximately 10 kilovolts. The voltage across a single electrode can also vary over time. The magnitude of the electroadhesion force can be adjusted, for example, by varying the area of ​​the contact surface, varying the applied voltage, and / or varying the distance between the electrode and the flexible article.

[0029] The electroadhesion device 100 may include a protective layer 150 surrounding the positive electrode 120, the negative electrode 130, and the dielectric material 140. The protective layer 150 is made of an insulating material.

[0030] Conventional electroadhesion devices typically include a gripping pad with a generally flat gripping surface to maximize the contact area between the gripping surface and the flexible object being picked up. To avoid wrinkles and creases on the flexible object, the flat electroadhesion pad's dimensions must match the object's size. However, producing large gripping pads is expensive, and a single gripping pad may not be able to handle flexible objects of varying sizes.

[0031] exist Figure 1 In the embodiment shown in FIG, the gripper surface 110 comprises a curved surface. Curved surfaces are effective when handling thin, flexible sheets such as textiles. The contact area between the gripper surface and the flexible sheet can be increased by rolling or rotating the electroadhesion device, which causes a larger portion of the flexible sheet to be wrapped around and adhered to the curved surface.

[0032] In one embodiment, electroadhesion device 100 is in the form of a roller, and gripping surface 110 has a substantially circular cross-section. A roller with a larger diameter provides a greater contact area between the gripping surface and the flexible object when the flexible object is wrapped around the roller. The length of the roller can be selected to match the size of the flexible object to be manipulated. In some embodiments, the roller length can be greater than the length of the edge of the flexible object, allowing the entire edge of the flexible object to be wrapped around the roller.

[0033] Figure 2A and 2B The operation of the electroadhesion roller 200 is shown. The electroadhesion roller 200 has a circular gripping surface 210 in cross-section, with positive and negative electrodes alternately embedded in a dielectric material inside the gripping surface 210. The flexible item to be picked up is a fabric sheet 800. Fabric sheet 800 may be the top sheet of a stack of fabric sheets. Fabric sheet 800 is generally rectangular in shape. Fabric sheet 800 has a first edge 801, a second edge 802, an upper surface 810, and a lower surface 820.

[0034] Figure 2A The figure shows a state where the electroadhesion roller 200 contacts the upper surface 810 near the first edge 801. A voltage can be applied to the electrodes to generate an electroadhesion force between the gripping surface 210 and the fabric sheet 800. The electroadhesion force causes the first edge 801 to adhere to the bottom portion 220 of the gripping surface 210. The electroadhesion roller 200 is then driven to roll over the fabric sheet 800, causing a larger portion of the fabric sheet 800 to be wrapped around the gripping surface 210. In some embodiments, the gripping surface 210 can be a rough surface to increase the friction between the gripping surface 210 and the upper surface 810 of the fabric sheet 800. Figure 2B It shows the state when half of the gripping surface 210 is covered by the fabric sheet 800. The first edge 801 is now located on top of the electroadhesion roller 200.

[0035] It should be noted that direct surface-to-surface contact is not always required. For example, when the electroadhesion roller 200 is placed close to the fabric sheet 800, the electroadhesion force can still attract the fabric sheet 800. The electroadhesion roller 200 can then be driven to rotate so that a larger portion of the fabric sheet 800 is wrapped around the gripping surface 210.

[0036] Although Figure 2A and 2B While an electroadhesive roller 200 is shown having a circular gripping surface 210, it will be appreciated that various alternative designs of electroadhesive devices may be employed. For example, the gripping surface may have an elliptical or semicircular cross-sectional shape. To avoid damaging the flexible item, it is preferred to avoid corners or abrupt changes in the gripping surface.

[0037] In some embodiments, the gripping surface may include a substantially flat portion that smoothly transitions to a curved surface. Figure 3A and 3B An electroadhesion roller 300 is shown having a racetrack-shaped gripping surface 310. The gripping surface 310 includes a flat portion 330 that smoothly transitions to a curved surface 320. The flat portion 330 can be disposed at the bottom of the electroadhesion device 300 so that the flat portion 330 always contacts and picks up the flexible item 800 before the curved surface 320. Figure 3B A state is shown in which both the flat portion 330 and the curved surface 320 are covered by the fabric sheet 800 .

[0038] Furthermore, it is contemplated that at least a portion of the electroadhesion device (e.g., the lower portion) could be made deformable. When the electroadhesion device is placed against a flexible object, an external force could be applied to the device, causing the lower portion to deform. This deformation of the lower portion allows the bottom portion of the gripping surface to conform to the surface of the flexible object. This increases the initial contact area between the gripping surface and the flexible object.

[0039] In certain embodiments, electrodes are removably mounted in the electroadhesion device. The electrodes may be in the form of strips, rods, or plates extending longitudinally along the electroadhesion device. The electrodes may be inserted into channels formed in the dielectric material. Removable electrodes facilitate replacement and maintenance of the device.

[0040] The rolling motion of the electroadhesion device can be considered a combination of translational motion and rotational motion, wherein the contact point is momentarily at rest. The rotational motion can be generated by an actuator, such as an electric motor. In one embodiment, the electroadhesion device can include a hole or recess for receiving a drive shaft coupled to the actuator. The gripping surface of the electroadhesion device can be a rough surface to increase the friction between the gripping surface and the flexible sheet. In addition, a downward force can be applied to press the electroadhesion device toward the flexible sheet. During the rolling motion, the rotational speed of the drive shaft and the downward force can be controlled to ensure that the flexible sheet is wrapped around the gripping surface.

[0041] Figure 4 A functional block diagram of an exemplary electroadhesion system for conveying flexible articles according to one embodiment of the present disclosure is shown. The electroadhesion conveying system 500 includes a first gripper 510 and a second gripper 520. Each of the two grippers 510, 520 can include one or more electroadhesion devices as described above. A support structure can be provided to support the first gripper 510 and the second gripper 520. A voltage source 530 is provided for applying a voltage to electrodes in the first gripper 510 and the second gripper 520. In some embodiments, the power source is used to provide an AC voltage or a DC voltage.

[0042] The electroadhesion transfer system 500 also includes a drive system 540 for actuating the first gripper 510 and the second gripper 520. The drive system 540 can include a plurality of drive modules, including a first gripper module for generating rolling or rotational motion of the first gripper, a first transfer module for generating translational motion of the first gripper, a second gripper module for generating rolling or rotational motion of the second gripper, and a second transfer module for generating translational motion of the second gripper. The drive modules can be controlled by a controller 550 that determines and controls the rolling distance, rotation angle, rotation speed, translation speed, and / or target position of the first gripper 510 and the second gripper 520.

[0043] Figure 5 An exemplary arrangement of a first gripper 510 and a second gripper 520 is shown. The first gripper 510 includes a first electroadhesion roller 511, while the second gripper 520 includes a second electroadhesion roller 521. The first electroadhesion roller 511 and the second electroadhesion roller 521 are spaced apart and oriented parallel to each other. During operation, the first electroadhesion roller 511 is controlled to roll in one direction to pick up one edge 801 of the flexible item 800, and the second electroadhesion roller 521 is controlled to roll in the opposite direction to pick up the opposite edge 802 of the flexible item 800. Figure 6 The state is shown when the electroadhesion rollers 511 , 521 have picked up the edges 801 , 802 of the flexible article 800 .

[0044] In other embodiments, the electroadhesive conveying system 500 may include more than two grippers. For example, four electroadhesive rollers may be used to pick up the four edges of a rectangular fabric sheet.

[0045] Each electroadhesive roller 511, 521 may be equipped with a sensor 512, 522 for detecting the area of ​​the flexible object wrapped around the roller surface. Various types of sensors may be used, including electronic sensors, optical sensors, and pressure sensors. In one embodiment, if the controller detects that more than half of the roller surface is covered by the flexible object, the controller may stop the rolling motion.

[0046] The gripping force generated may be affected by a variety of factors, including the applied voltage, the arrangement of the electrodes in the electroadhesion roller, the winding area, and the material of the flexible article. The controller 550 may include a voltage control unit 552 for controlling the voltage applied to the electrodes based on the properties of the flexible article and the parameters of the electroadhesion roller. The controller 550 may also include a rolling control unit 551 for controlling the rolling distance or rotation angle of the electroadhesion roller based on various operating parameters. The operating parameters may include the number of electrodes in the first and second electroadhesion rollers, the arrangement of the electrodes, the size (diameter and length) of the first and second electroadhesion rollers, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the friction coefficient of the flexible article.

[0047] In one embodiment, the electroadhesive transfer system 500 may include a user interface 560 that allows a user to input position information of the flexible article to be transferred, set properties of the flexible article, and / or select a specific operating mode from a plurality of preset modes stored in the controller 550 .

[0048] For the electroadhesion conveying system 500, it is important to know the exact position of the flexible item 800. The controller 550 can control the drive system 540 to move the first electroadhesion roller 511 and the second electroadhesion roller 521 to the correct position to pick up the flexible item. In one embodiment, the user interface allows the user to manually set the position of the flexible item. Alternatively or additionally, the controller 550 may include an edge detection module 553 for detecting the position of the flexible item, in particular the position of the edge of the flexible item. The edge detection module 553 can also assist the drive system 540 in aligning the first electroadhesion roller 511 and the second electroadhesion roller 521 with the edges 801 and 802 of the flexible item 800. The edge detection module may include a computer vision system, an optical sensor, an ultrasonic sensor, or any other sensor capable of detecting the edge of a flexible item.

[0049] In another embodiment, electroadhesion rollers 511, 521 can be formed by connecting multiple roller segments. All roller segments can have the same cross-sectional shape and can be configured to be driven by the same actuator. The number of roller segments can be selected to match the edge length of the flexible article to be conveyed. This is particularly advantageous when the system is used to convey flexible articles of varying sizes, including very large sheets of fabric.

[0050] Figure 7 A flow chart of a method 600 for transferring a flexible article according to an embodiment of the present disclosure is shown. The method 600 may be performed by Figure 4The electroadhesion transfer system 500 shown in FIG. In step 601, position information of the flexible article 800 is collected. This position information can be set by a user through the user interface 560 or detected by a computer vision system or sensor of the edge detection module 553. The position information includes information about the two edges 801 and 802 of the flexible article 800.

[0051] In step 602, a first gripper 510 is aligned with a first edge 801 of a flexible article 800. The first gripper may include at least one electroadhesion device as described above, such as an electroadhesion roller having a circular cross-section. The first gripper may be moved by a drive system 540. Alignment between the longitudinal axis of the first gripper and the first edge may be assisted by an edge detection unit 553.

[0052] In step 603, a first gripper is placed in contact with a first edge of the flexible article. The first gripper can be lowered by a drive system until it contacts the surface of the flexible article.

[0053] In step 604, a voltage is applied to electrodes in the first gripper to establish electrical adhesion between the first gripper and the first edge. The voltage can be controlled based on the properties of the flexible object and parameters of the first gripper. Once the first edge is firmly adhered to the gripping surface of the first gripper, a signal can be sent to a controller.

[0054] In step 605, the first gripper is rolled in a first direction so that a first portion of the flexible article near the first edge is wrapped around a gripping surface of the first gripper. The rolling distance can be controlled based on the number of electrodes in the first gripper, the arrangement of the electrodes, the size of the first gripper, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the coefficient of friction of the flexible article. In one embodiment, the wrapping area of ​​the first edge on the gripping surface is detected. The detected wrapping area can help the controller determine whether the first gripper has rolled the correct distance.

[0055] In step 606, the second gripper 520 is aligned with the second edge 802 of the flexible article 800. The second gripper may also include at least one electroadhesion device as described above, such as an electroadhesion roller having a circular cross-section. Similar to step 602, an edge detection unit may assist in aligning the longitudinal axis of the second gripper with the second edge.

[0056] In step 607, a second gripper is placed in contact with a second edge of the flexible article. The second gripper can be lowered by the drive system until it contacts the surface of the flexible article.

[0057] In step 608, a voltage is applied to electrodes in the second gripper to establish electrical adhesion between the second gripper and the second edge. The voltage can be controlled based on the properties of the flexible article and parameters of the second gripper. Once the second edge is firmly adhered to the surface of the second gripper, a signal is sent to a controller.

[0058] In step 609, the second gripper is rolled in a second direction opposite to the first direction so that a second portion of the flexible article proximate the second edge is wrapped around the gripping surface of the second gripper. The rolling distance can be controlled based on the number of electrodes in the second gripper, the arrangement of the electrodes, the size of the second gripper, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the coefficient of friction of the flexible article. In one embodiment, the wrapping area of ​​the second edge on the gripping surface is detected. The detected wrapping area can help the controller determine whether the second gripper has rolled the correct distance.

[0059] It will be appreciated that the first gripper and the second gripper may be controlled separately.In one embodiment, steps 602 to 605 and steps 606 to 609 may be performed simultaneously to improve the efficiency of the gripping operation.

[0060] In step 610, the first gripper and the second gripper carrying the two edges of the flexible article are moved to the target position. Preferably, the distance between the two grippers is maintained during step 610 to prevent the flexible article from being stretched and wrinkled or folded. Rotation and rolling of the grippers are also avoided.

[0061] When the flexible article reaches the target location, the voltage applied to the electrodes in the first gripper and the second gripper can be reduced to release the two edges of the flexible article from the gripping surface. In some embodiments, the target location can be a work platform.

[0062] Although the disclosed subject matter has been described and illustrated in the foregoing exemplary embodiments, it is to be understood that the present disclosure is by way of example only and that various changes may be made to the implementation details of the disclosed subject matter without departing from the spirit and scope of the disclosed subject matter. In addition, although a particular feature of the present invention may be disclosed with respect to only one of the multiple embodiments, that feature may be combined with one or more other features of the other embodiments according to the needs and advantages of any given or particular application.

Claims

1. An electroadhesion device for manipulating a flexible object, comprising: a gripping surface for picking up the flexible item; a plurality of electrodes located on an inner side of the gripping surface; as well as a dielectric material positioned between the electrodes; wherein the voltage difference between adjacent electrodes generates an electroadhesive force, causing the flexible object to adhere to the gripping surface; The gripping surface comprises a curved surface, and the electroadhesion device is capable of rolling on the flexible article or rotating about a rotation axis, so that at least a portion of the flexible article is capable of wrapping around the curved surface.

2. The electroadhesion device according to claim 1, wherein The plurality of electrodes includes positive electrodes and negative electrodes embedded in the dielectric material in an alternating manner, and the electroadhesive device includes a protective layer surrounding the positive electrodes, the negative electrodes, and the dielectric material.

3. The electroadhesion device according to claim 1 or 2, wherein: The electroadhesive device is in the form of a roller, and the gripping surface is substantially circular in cross-section.

4. The electroadhesion device according to claim 1 or 2, wherein: The gripping surface includes a substantially flat portion that smoothly transitions to the curved surface, the substantially flat portion being configured to contact the flexible article prior to the curved surface.

5. The electroadhesion device according to claim 1 or 2, wherein: At least a portion of the electroadhesion device is deformable to increase an initial contact area between the gripping surface and the flexible article.

6. The electroadhesion device according to any one of claims 1 to 5, wherein: The electrode is removably mounted to the electroadhesion device.

7. The electroadhesion device according to any one of claims 1 to 6, wherein: The gripping surface is a rough surface to increase friction when the electroadhesion device rolls over the flexible object.

8. The electroadhesion device according to any one of claims 1 to 7, wherein The electroadhesion device is driven by an actuator to roll or rotate, and the electroadhesion device includes a hole or a recess for receiving a drive shaft coupled to the actuator.

9. An electroadhesion system for conveying flexible articles, comprising: a first gripper comprising at least one electroadhesion device according to any one of claims 1 to 8; a second gripper comprising at least one electroadhesion device according to any one of claims 1 to 8; a voltage source for applying a voltage to electrodes in the first gripper and the second gripper; a drive system for actuating the first gripper and the second gripper; as well as A controller for controlling operation of the first gripper and the second gripper.

10. The electroadhesion system according to claim 9, wherein: The first gripper includes a first electroadhesion roller and the second gripper includes a second electroadhesion roller, the first and second electroadhesion rollers being oriented parallel to each other and being individually controlled.

11. The electroadhesion system according to claim 10, wherein: The first electroadhesion roller is controlled to roll in one direction to pick up one edge of the flexible article, and the second electroadhesion roller is controlled to roll in an opposite direction to pick up an opposite edge of the flexible article.

12. The electroadhesion system according to claim 10 or 11, wherein: The first and second electroadhesion rollers each include a sensor for detecting a wrap area of ​​the edge of the flexible article on the gripping surface.

13. The electroadhesion system according to any one of claims 9 to 12, wherein: The controller includes a rolling control unit for controlling the rolling distance or rotation angle of the first electroadhesion roller and the second electroadhesion roller based on operating parameters selected from the group consisting of: the number of electrodes in the first electroadhesion roller and the second electroadhesion roller, the size of the first electroadhesion roller and the second electroadhesion roller, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the friction coefficient of the flexible article.

14. The electroadhesion system according to any one of claims 9 to 13, wherein: The controller includes a voltage control unit for controlling a voltage applied to the electrodes based on properties of the flexible article and parameters of the first and second electroadhesion rollers.

15. The electroadhesion system according to any one of claims 9 to 14 further comprises a user interface for a user to input position information of the flexible article to be transferred, set properties of the flexible article, and / or select a specific operating mode from a plurality of preset modes stored in the controller.

16. The electroadhesion system according to any one of claims 9 to 15, wherein: The controller includes an edge detection unit for detecting the position of the edge of the flexible article and assisting the first and second electroadhesion rollers in aligning with the edge of the flexible article, wherein the edge detection unit includes one or more sensors or an AI-based computer vision system.

17. The electroadhesion system of claim 9, wherein: The first gripper and / or the second gripper comprises a plurality of electroadhesion devices connected together and configured to be driven by the same actuator during operation. Preferably, the number of electroadhesion devices in the first gripper and / or the second gripper is selected to match the size of the flexible article to be conveyed.

18. A method for conveying a flexible article, comprising: placing a first gripper in contact with a first edge of the flexible article, wherein the first gripper comprises at least one electroadhesion device according to any one of claims 1 to 8; applying a first voltage to electrodes in the first gripper to establish electrical adhesion between the first gripper and the first edge; rolling the first gripper in a first direction so that a first portion of the flexible article near the first edge is wrapped around the first gripper; placing a second gripper in contact with a second edge of the flexible article, wherein the second gripper comprises at least one electroadhesion device according to any one of claims 1 to 8; applying a second voltage to electrodes in the second gripper to establish electrical adhesion between the second gripper and the second edge; rolling the second gripper in a second direction opposite to the first direction so that a second portion of the flexible article proximate the second edge is wrapped around the second gripper; as well as Move the first gripper and the second gripper to the target position.

19. The method for conveying a flexible article according to claim 18, wherein: The first gripper includes a first electroadhesive roller and the second gripper includes a second electroadhesive roller, the first and second electroadhesive rollers being oriented parallel to each other with the first and second edges of the flexible article opposing each other.

20. The method for conveying a flexible article according to claim 19, wherein: While the first and second electroadhesion rollers are moving toward a target location, rotational movement of the first and second electroadhesion rollers is disabled.

21. The method for conveying a flexible article according to claim 19 or 20, wherein: The step of rolling the first gripper in a first direction includes: driving a first electroadhesion roller to roll a first distance on the flexible article; and The step of rolling the second gripper in the second direction includes: driving the second electroadhesion roller to roll a second distance over the flexible article; The first distance and the second distance are determined based on operating parameters selected from the group consisting of: the number of electrodes in the first electroadhesion roller and the second electroadhesion roller, the size of the first electroadhesion roller and the second electroadhesion roller, the composition of the flexible article, the thickness of the article material, the density of the flexible article, and the friction coefficient of the flexible article.

22. The method for conveying a flexible article according to any one of claims 19 to 21, further comprising: prior to the step of applying a first voltage to the electrodes in the first gripper, aligning a longitudinal axis of a first electroadhesion roller with a first edge of the flexible article; as well as prior to the step of applying a second voltage to the electrodes in the second gripper, aligning the longitudinal axis of the second electroadhesion roller with the second edge of the flexible article, The alignment of the first electroadhesion roller and the second electroadhesion roller is assisted by an edge detection unit.

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