PINS

BACKGROUND

[0001] In several industries, such as the manufacturing industry, warehousing and packaging industry, etc., operations involve picking, handling, and shuttling items (e.g., components, workpieces, items to be packaged and shipped, etc.). Operations may further involve combining several items in a package or a kit, which can be referred to as a kitting operation.

[0002] Picking operations can be accomplished via manual labor or an automated system that reduces the need for manual labor. Automated systems can involve robots configured to pick items.

[0003] Available picking automation solutions are currently limited by adaptability, reliability, and complexity of the systems. Particularly, while a robot might be available to pick a particular type of items, such robot may be challenged in picking a different type of item having a different geometry or configuration, or where items are stacked in a particular manner. In other words, existing robots might not be suited for high-mix environments where different types of items arranged in different configurations are to be picked.

[0004] It may thus be desirable to have a robotic gripper that is versatile to enable a robot to pick items in high-mix environment. It is with respect to these and other considerations that the disclosure made herein is presented. SUMMARY

[0005] Within examples described herein, the present disclosure describes implementations that relate to a robotic gripper with a finger having a matrix of spring-loaded pins.

[0006] In a first example implementation, the present disclosure describes a finger. The finger includes: a pin housing; a plurality of pins disposed partially in the pin housing, each pin being configured to be movable within the pin housing; and a spring plate, wherein each pin of the plurality of pins is spring-loaded by a spring disposed between the pin and the spring plate.

[0007] In a second example implementation, the present disclosure describes a robotic gripper including a plurality of gripper arm assemblies, wherein a gripper arm assembly of the plurality of gripper arm assemblies comprises: an arm linkage and the finger of the first example implementation pivotably coupled to the arm linkage.

[0008] In a third example implementation, the present disclosure describes a robot including a robot arm and the robotic gripper of the second example implementation coupled to the arm robot.

[0009] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, implementations, and features described above, further aspects, implementations, and features will become apparent by reference to the figures and the following detailed description.

BRIEF DESCRIPTION OF THE FIGURES

[0010] The novel features believed characteristic of the illustrative examples are set forth in the appended claims. The illustrative examples, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to the following detailed description of an illustrative example of the present disclosure when read in conjunction with the accompanying Figures.

[0011] Figure 1 illustrates a schematic view of a robot, in accordance with an example implementation.

[0012] Figure 2 illustrates a perspective view of a robotic gripper, in accordance with an example implementation, in accordance with an example implementation.

[0013] Figure 3 illustrates a side view of the robotic gripper shown in Figure 2, in accordance with an example implementation.

[0014] Figure 4 illustrates a top view of the robotic gripper shown in Figure 2, in accordance with an example implementation.

[0015] Figure 5 illustrates a perspective view of a gripper arm assembly, in accordance with an example implementation.

[0016] Figure 6 illustrates a side view of the gripper arm assembly shown in Figure 5, in accordance with an example implementation.

[0017] Figure 7 illustrates another side view of the gripper arm assembly shown in Figure 5, in accordance with an example implementation.

[0018] Figure 8 illustrates a top view of the gripper arm assembly shown in Figure 5, in accordance with an example implementation. [0019] Figure 9 illustrates a perspective view of the robotic gripper of Figure 2 operating in a three-finger configuration, in accordance with an example implementation.

[0020] Figure 10 illustrates a top view of the robotic gripper operating in the three-finger configuration, in accordance with an example implementation.

[0021] Figure 11 illustrates a perspective view of the robotic gripper of Figure 2 operating in a two-finger configuration, in accordance with an example implementation.

[0022] Figure 12 illustrates a top view of the robotic gripper operating in the two-finger configuration, in accordance with an example implementation.

[0023] Figure 13 illustrates a perspective view of the robotic gripper of Figure 2 operating in a vacuum-only configuration, in accordance with an example implementation.

[0024] Figure 14 illustrates a side view of the robotic gripper operating in the vacuum-only configuration, in accordance with an example implementation.

[0025] Figure 15 illustrates operating the robotic gripper initially in a vacuum-only configuration to attach to a book and raise the book from a binding side, in accordance with an example implementation.

[0026] Figure 16 illustrates operating the robotic gripper in a three-finger configuration and using two combined arms to provide support for the book, in accordance with an example implementation.

[0027] Figure 17 illustrates using the other two fingers to stabilize and complete picking operation of the book, in accordance with an example implementation.

[0028] Figure 18 illustrates picking a wine glass, in accordance with an example implementation. [0029] Figure 19 illustrates a perspective view of a finger, in accordance with an example implementation.

[0030] Figure 20 illustrates a top view of the finger of Figure 19, in accordance with an example implementation.

[0031] Figure 21 illustrates a side view of the finger of Figure 19, in accordance with an example implementation.

[0032] Figure 22 illustrates a front view of the finger of Figure 19, in accordance with an example implementation.

[0033] Figure 23 illustrates a rear view of the finger of Figure 19, in accordance with an example implementation.

[0034] Figure 24 illustrates a bottom view of the finger of Figure 19, in accordance with an example implementation.

[0035] Figure 25 illustrates another top view of the finger of Figure 19 in another orientation, in accordance with an example implementation.

[0036] Figure 26 illustrates a cross-sectional view of the finger of Figure 25, in accordance with an example implementation.

DETAILED DESCRIPTION

[0037] Disclosed examples will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all of the disclosed examples are shown. Indeed, several different examples may be described and should not be construed as limited to the examples set forth herein. Rather, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0038] Robots are used in industrial and warehousing facilities to perform various tasks. For example, an industrial robot is a robot system used for manufacturing. Industrial robots are automated, programmable and capable of movement on three or more axes. Typical applications of industrial robots include welding, painting, assembly, disassembly, pick and place, packaging and labeling, palletizing, product inspection, and testing. Robots can also assist in material handling.

[0039] Similarly, warehouse robots can help pick, pack, and sort items being handled at warehouses. Example robots can have articulated robotic arms configured for picking and placing operations. Such articulated robotic arms are multi-jointed limbs used to manipulate products within distribution centers, warehouses, and manufacturing facilities.

[0040] Figure 1 illustrates a schematic view of a robot 100, in accordance with an example implementation. The robot 100 includes a base 102 and a robotic arm 104 comprising an arm mount 106. The robotic arm 104 includes a first robot arm segment 108 coupled to the arm mount 106 at an articulating joint 109, and the robotic arm 104 also includes a second robot arm segment 110 connected to the first robot arm segment 108 via an articulating joint 112. The robot 100 also includes a robotic gripper 114 coupled to the second robot arm segment 110. [0041] The robot 100 is represented herein as a generic industrial robot; however, it should be understood that the robotic gripper implementation described throughout this disclosure could be used with any type of robots including articulate robots, Cartesian coordinate robots, cylindrical coordinate robots, spherical coordinate robots, Selective Compliance Assembly Robot, Delta robot, serial manipulators, parallel manipulators, etc.

[0042] The robotic gripper 114 can also be referred to as an end-of-arm-tooling (EOAT) or end- effector. The robotic gripper 114 is a device that enables picking, holding, handling, tightening, and releasing of an object. Different configurations of robotic grippers can be used. In an example, the robotic gripper 114 can be a mechanical gripper as illustrated in Figure 1 where the robotic gripper has mechanical fingers to manipulate objects.

[0043] The number of robot fingers varies depending on the tasks required by the robot 100. For instance, the number of fingers can be between two and four fingers. A two- or three-finger robotic gripper may be suitable for picking up some types of objects but might not be suitable for picking up other objects such as books lined up in a stack or a liquid container with unstable momentum that might be spill-prone.

[0044] In another example, the robotic gripper comprises a vacuum gripper that grips objects through a suction cup. A vacuum gripper can be used for handling objects with uneven surfaces or irregular shapes. Such vacuum grippers can be with or without fingers. Without fingers, a vacuum gripper may be challenged to pick thin items that do not have a large surface to grip on. A vacuum gripper may also have difficulty picking a book from a stack, particularly if the suction is applied far from the binding side of the book because such suction may cause the cover of the book to open up, but might not allow the whole book to be picked in an orderly non damaging manner. [0045] In some cases, fingers may be combined with a suction cup. Such a vacuum gripper with fingers may similarly have difficulty picking up objects such as liquid containers and books. For instance, it may be difficult for a vacuum gripper with fingers to pick a book that is resting on a stack of books where the books are flush so that the book is not protruding from the stack. As mentioned above, vacuum suction may cause the book cover to open without picking the entire book. Further, approaching the book from the side with the fingers might also fail as the fingers might not be able to be inserted between two books, particularly if the book is disposed within a bin.

[0046] In another example, the fingers may be configured as soft grippers that are suitable for fragile objects such as glasses. However, such soft grippers might not be suitable for heavier objects, liquid containers, books, among other objects.

[0047] As such, existing gripper solutions are not configured to be sufficiently versatile to pick a variety of items in a high-mix environment. Particular grippers are suitable for a group of objects but not suitable other groups of objects. Thus, in a high-mix environment where a robot is required to pick and move a variety of items with different configuration, existing grippers may fail to pick all the items. Replacing grippers often to suit a particular group of items is not practical.

[0048] It may thus be desirable to provide a robotic gripper that is versatile and flexible. Disclosed herein are robotic grippers that can adapt to the shape and configuration of a variety of items in a high-mix of environment. Such robotic grippers increase the range of objects that can be picked with accuracy without tool changing, manual intervention, or causing objects to drop.

[0049] Particularly, disclosed herein is a robotic gripper having a plurality of arm assemblies coupled to a frame or base. An example arm assembly includes an arm pivot bracket rotatably coupled to the base, an arm linkage pivotably coupled to the arm pivot bracket, and a finger pivotably coupled to the arm linkage. Rotation of the arm pivot bracket relative to the base, pivoting motion of the arm linkage relative to the arm pivot bracket, and pivoting motion of the finger relative to the arm linkage are each controlled independently by a respective actuator. As such, each arm assembly provides three degree-of-freedom (DOF) motion. Having multiple arm assemblies coupled to the base provides a multiple DOF gripper that can adapt to a variety of objects in a high-mix environment. Further, some degrees of freedom of such robotic gripper may be coupled by a common actuator to reduce cost and complexity based on the application.

[0050] Further, disclosed herein is finger for a robotic gripper, with the finger having a matrix of spring-loaded pins. The finger can also have a force sensor (e.g., a load cell) that provides an indication of a magnitude of force that the finger is applying or the weight that the finger is carrying.

[0051] Figure 2 illustrates a perspective view of a robotic gripper 200, Figure 3 illustrates a side view of the robotic gripper 200, and Figure 4 illustrates a top view of the robotic gripper 200, in accordance with an example implementation. Figures 2-4 are described together. The robotic gripper 200 can, for example, be coupled to the second robot arm segment 110 and can represent the robotic gripper 114.

[0052] The robotic gripper 200 includes a base plate 202. The base plate 202 can also be referred to as a base or frame of the robotic gripper 200. The base plate 202 can be configured as a disk as shown in Figures 2-4.

[0053] The robotic gripper 200 also includes a plurality of gripper arm assemblies rotatably- coupled to the base plate 202. For example, the robotic gripper 200 includes four gripper arm assemblies, gripper arm assembly 204, gripper arm assembly 206, gripper arm assembly 208, and gripper arm assembly 210.

[0054] Figure 5 illustrates a perspective view of the gripper arm assembly 204, Figure 6 illustrates a side view of the gripper arm assembly 204, Figure 7 illustrates another side view of the gripper arm assembly 204, and Figure 8 illustrates a top view of the gripper arm assembly 204, in accordance with an example implementation. Figures 5-8 are described together.

[0055] The gripper arm assembly 204 includes a gripper arm 300. The gripper arm 300 is a multi-jointed arm and includes an arm linkage 302 and a finger 304, where the finger 304 is pivotably-coupled to the arm linkage 302 at finger pivot pin 305 mounted at a joint 307 between the arm linkage 302 and the finger 304. The finger 304 is coupled to the finger pivot pin 305 and is configured to pivot or rotate about an axis of the finger pivot pin 305. As an example for illustration, the finger 304 can be configured to rotate through a range of angles of up to 220 degrees.

[0056] The gripper arm assembly 204 further includes an arm pivot bracket 306. The arm pivot bracket 306 is configured to be rotatably mounted to the base plate 202 of the robotic gripper 200. Particularly, the arm pivot bracket 306 is coupled to the base plate 202 but is allowed to rotate about the top surface of the base plate 202 as described below, thereby rotating the gripper arm 300 circumferentially about the base plate 202.

[0057] The arm pivot bracket 306 has radial ear 308 and radial ear 310 that extend radially - outward from the arm pivot bracket 306. The gripper arm assembly 204 includes a finger drive shaft 312 that extends between the radial ears 308, 310 and is configured to operate as a pivot pin about which the arm linkage 302 rotates. [0058] The arm pivot bracket 306 further has side ear 314 and side ear 316 that extend sideways from the arm pivot bracket 306. The gripper arm assembly 204 includes a finger drive input shaft 318 pass through the side ears 314, 316. Particularly, a shaft bearing 320 is mounted to the finger drive input shaft 318 and is disposed within the side ear 314 to allow the finger drive input shaft 318 to rotate about its axis relative to the arm pivot bracket 306. Another shaft bearing (not shown) can be mounted to the finger drive input shaft 318 within the side ear 316.

[0059] The finger drive input shaft 318 is coupled or drivingly connected to a finger drive worm gear 322 (i.e., a worm screw) configured to have helical or spiral threads. The finger drive worm gear 322 can be mounted to, or be made integral with, the finger drive input shaft 318 and is interposed between the side ears 314, 316.

[0060] The finger drive worm gear 322 meshes with a finger drive gear such as finger drive worm wheel 324 configured as a spur gear, for example. The helical threads of the finger drive worm gear 322 are butted up against teeth of the finger drive worm wheel 324.

[0061] The robot 100 has a plurality of actuators such as a gripper finger actuator 326 configured to rotate the finger drive input shaft 318. The gripper finger actuator 326 can include any type of rotary actuator such as a motor (e.g., electric, pneumatic, or hydraulic motor) or a combination of a motor and gear reducer, for example.

[0062] As the gripper finger actuator 326 is activated or commanded by a controller of the robot 100 to rotate the finger drive input shaft 318, the finger drive worm gear 322 rotates therewith. Thus, the finger drive worm gear 322 rotates against the finger drive worm wheel 324, and the threads of the finger drive worm gear 322 pushes on the teeth of the finger drive worm wheel 324, thereby causing the finger drive worm wheel 324 to rotate. [0063] This arrangement changes rotational movement or the plane of movement of the finger drive worm gear 322 by 90 degrees to the finger drive worm wheel 324. The finger drive worm wheel 324 is mounted to the finger drive shaft 312 such that as the finger drive worm wheel 324 rotates, the finger drive shaft 312 rotates therewith. The finger drive shaft 312 passes through a hole in the arm linkage 302 and does not cause the arm linkage 302 to rotate.

[0064] With this configuration, the finger drive shaft 312 can have a reduced rotational speed compared to the finger drive worm gear 322. However, the torque transmitted to the finger drive shaft 312 is higher than the torque applied to the finger drive worm gear 322.

[0065] The finger drive shaft 312 can have has a sprocket, pulley, or gear teeth formed at its end close to the radial ear 310. Similarly, the finger pivot pin 305 has a corresponding sprocket, pulley, or gear teeth. The gripper arm assembly 204 includes a finger drive belt 328 (toothed belt) that engages the teeth of the finger drive shaft 312 and the teeth of the finger pivot pin 305. This way, the finger drive belt 328 mechanically couples the finger drive shaft 312 to the finger pivot pin 305, such that as the finger drive shaft 312 rotates, the finger pivot pin 305 rotates, causing the finger 304 to rotate therewith relative to the arm linkage 302 about the axis of the finger pivot pin 305.

[0066] The gripper arm assembly 204 further includes an arm drive input shaft 330 configured to be driven by an gripper arm actuator 332. Similar to the gripper finger actuator 326, the gripper arm actuator 332 can include any type of rotary actuator such as a motor (e.g., electric, pneumatic, or hydraulic motor) or a combination of a motor and gear reducer, for example.

[0067] Referring to Figure 7, the arm drive input shaft 330 is coupled or drivingly connected to an arm drive worm gear 334 (i.e., a worm screw) configured to have helical or spiral threads. The arm drive worm gear 334 can be mounted to, or be made integral with, the arm drive input shaft 330.

[0068] As shown in Figures 5-8, a portion of an end of the arm linkage 302 is configured as an arm drive gear having spur gear teeth. The portion is referred to herein as arm drive worm wheel 336. The arm drive worm gear 334 meshes with the arm drive worm wheel 336. The helical threads of the arm drive worm gear 334 are butted up against teeth of the arm drive worm wheel 336.

[0069] As the gripper arm actuator 332 is activated or commanded by the controller of the robot 100, the arm drive input shaft 330 rotates and the arm drive worm gear 334 rotates therewith. Thus, the arm drive worm gear 334 rotates against the arm drive worm wheel 336, and the threads of the arm drive worm gear 334 pushes on the teeth of the arm drive worm wheel 336, thereby causing the arm drive worm wheel 336 and the arm linkage 302 to rotate about an axis of the finger drive shaft 312.

[0070] The gripper arm assembly 204 further includes an angular drive gear 338. The arm drive input shaft 330 passes through the angular drive gear 338 and rotates relative to the angular drive gear 338 when the gripper arm actuator 332 is activated. In other words, rotation of the arm drive input shaft 330 is independent of the angular drive gear 338 and does not cause the angular drive gear 338 to rotate and vice versa (rotation of the angular drive gear 338 does not cause the arm drive input shaft 330 to rotate). For example, the angular drive gear 338 an be mounted on a bearing disposed about the arm drive input shaft 330).

[0071] As shown schematically in Figure 5, the robot 100 includes an angular drive actuator 340 configured to drive the angular drive gear 338. Similar to the gripper finger actuator 326 and the gripper arm actuator 332, the angular drive actuator 340 can include any type of rotary actuator such as a motor (e.g., electric, pneumatic, or hydraulic motor) or a combination of a motor and gear reducer, for example.

[0072] The angular drive gear 338 is attached or coupled to the arm pivot bracket 306 such that rotation of the angular drive gear 338 causes the arm pivot bracket 306, as well as the components mounted to the arm pivot bracket 306 (e.g., the gripper arm 300), to rotate about the surface of the base plate 202 around an axis of the angular drive gear 338. In other words, rotation of the angular drive gear 338 causes the gripper arm 300 to rotate circumferentially about the base plate 202.

[0073] As such, the gripper arm 300 has three degrees of freedom. The first degree of freedom is associated with rotation of the finger 304 about the finger pivot pin 305 relative to the arm linkage 302. The second degree of freedom is associated with rotation of the arm linkage 302 about the finger drive shaft 312 relative to the arm pivot bracket 306. The third degree of freedom is associated with rotation of the arm pivot bracket 306 and the gripper arm 300 about the axis of the angular drive gear 338.

[0074] The finger 304 has a fingertip 342. In an example, the fingertip 342 is integral with the finger 304. In another example, the fingertip 342 is removable and replaceable with other fingertips having different materials. As such, the fingertip 342 can be selected to match a particular application or particular item to be picked by the robotic gripper 200.

[0075] In an example, the fingertip 342 is configured to have variable stiffness. In other words, the stiffness of the fingertip 342 can be varied to adapt to different stages of a picking operation and adapt to the configuration of the item being picked. For instance, as the finger 304 approaches an item and the fingertip 342 contacts the item, the fingertip 342 is made to be soft (i.e., made to be compliant and having low stiffness) so it does not damage the item and also to allow the fingertip 342 to conform to the shape of the item. The stiffness of the fingertip 342 can then be increased to make the fingertip 342 more rigid to lock the fingertip 342 in a conforming position about the item to achieve an optimal grip contact area between the fingertip 342 and the item.

[0076] Variable stiffness of the fingertip 342 can be achieved in several ways. For example, a granular jamming technique can be used where the fingertip 342 encloses granular materials, which is allowed to conform around the item to be picked. Once contact has been made around the item, a vacuum is generated within the fingertip 342, locking the fingertip 342 in a conforming position about the item. In an example, vacuum generation can be used alone without using granular materials within the fingertip 342

[0077] In another example, the fingertip 342 can be made of an electro active polymer material, where passing an electric current through the electro active polymer material changes the stiffness thereof. Another example technique involves using shape memory alloys that can change shape and stiffness based on a magnitude of an electric current passing therethrough. In another example, the fingertip 342 includes a magnetorheological material that changes its stiffness based on a strength of a magnetic field applied to the magnetorheological material within the fingertip 342.

[0078] Referring back to Figures 2-4, the gripper arm assemblies 206, 208, 210 are configured similar to the gripper arm assembly 204. For example, as shown in Figure 2, the gripper arm assembly 206 includes gripper arm 344 having arm linkage 346 and finger 348, finger drive input shaft 350, finger drive belt 352, arm drive input shaft 354, arm pivot bracket 356, and angular drive gear 358. [0079] Similarly, as shown in Figure 4, the gripper arm assembly 208 includes gripper arm 360 having arm linkage 362 and finger 364, finger drive input shaft 366, finger drive belt 368, arm drive input shaft 370, arm pivot bracket 372, and angular drive gear 374. As shown in Figure 2, the gripper arm assembly 210 includes gripper arm 376 having arm linkage 378 and finger 380, finger drive input shaft 382, finger drive belt 384 (shown in Figure 4), arm drive input shaft 386, arm pivot bracket 388, and angular drive gear 390.

[0080] Further, referring to Figures 2 and 3, the robotic gripper 200 can also include a suction cup 394 coupled to the base plate 202. A shown schematically in Figure 4, a vacuum generating device 392 (e.g., a blower) can be configured to generate a vacuum environment within the suction cup 394. For example, the robot 100 or a remote system fluidly coupled to the robot 100 via conduits (e.g., tubes, pipes, hoses, etc.) can include the vacuum generating device 392. The base plate 202 has a hole 396 that allows for a vacuum environment to be generated within the suction cup 394.

[0081] As the robotic gripper 200 approaches an item to be picked, the vacuum environment can be generated within the suction cup 394, causing a suction force to be applied to the item, thereby drawing or pulling the item toward the suction cup 394. With this configuration of the robotic gripper 200, the suction cup 394 operates as a human thumb, whereas the gripper arms 300, 344, 360, and 376 operate as the remaining fingers of a human hand.

[0082] This human-like configuration of the robotic gripper 200 provides enhanced dexterity compared to existing grippers. Particularly, with each gripper arm having three degree of freedoms, the robotic gripper 200 can potentially have twelve degrees of freedom. However, the configuration shown in Figures 2-4 couples the angular motion of the gripper arms 300, 344 together because the angular drive gears 338, 358 engage or mesh with each other, and thus one angular actuator (e.g., the angular drive actuator 340 shown in Figure 5) actuates both the angular drive gears 338, 358. As such, angular motion of the gripper arms 300, 344 takes place in tandem with each other, and they rotate in opposite directions, either toward each other or away from each other.

[0083] Similarly, angular motions of the gripper arms 360, 376 are coupled because the angular drive gears 374, 390 engage or mesh with each other, and thus one angular actuator actuates both the angular drive gears 374, 390. As such, angular motion of the gripper arms 360, 376 takes place in tandem with each other. This way, the robotic gripper 200 has ten degrees of freedom. However, it should be understood that the robotic gripper 200 can potentially have twelve degrees of freedom. The number of degrees of freedom can be reduced by coupling some of the input shafts together and using a reduced number of actuators.

[0084] The configuration of the robotic gripper 200 offers enhanced versatility and adaptability that may facilitate picking a wide variety or high-mix of items. For example, Figures 2-4 illustrates the robotic gripper 200 in a four-finger configuration, which may be suitable for picking certain items that require four fingers controlled independently to capture the item.

[0085] The robotic gripper 200 can operate in other configurations due to the large number of degrees of freedom it has. For example, rather than operating in a four-finger configuration, two of the gripper arms can be actuated in unison such that they operate as a single arm, while the two remaining gripper arms are controlled independently, thereby rendering the robotic gripper 200 operating as a three-finger gripper.

[0086] Figure 9 illustrates a perspective view of the robotic gripper 200 operating in a three- finger configuration, Figure 10 illustrates a top view of the robotic gripper 200 operating in the three-finger configuration, in accordance with an example implementation. As shown in Figures 9-10, the angular drive gear 374 of the gripper arm assembly 208 can be driven clockwise (from the perspective of the top view of Figure 10) or the angular drive gear 390 of the gripper arm assembly 210 can be driven counter-clockwise (from the perspective of the top view of Figure 10), thereby rotating the gripper arm assembly 208 and the gripper arm assembly 210 toward each other until they are parallel.

[0087] The gripper arms 360, 376 can then be controlled in tandem such that the gripper arms 360, 376 move in unison as if they are one larger arm. In other words, the same command is sent to the actuators of the finger drive input shafts 366, 382 and the same command is sent to the actuators of the arm drive input shafts 370, 386 such that motion of the arm linkages 362, 378 and the fingers 364, 380 is duplicated and the gripper arms 360, 376 move as one gripper arm. On the other hand, the remaining two gripper arm assemblies (i.e., the gripper arm assemblies 204, 206) are controlled independently. As such, the robotic gripper 200 operates in a three- finger configuration.

[0088] In another example, the robotic gripper 200 an operate in a two-finger configuration where one pair of gripper arms is actuated in unison such that they operate as a single gripper arm, and the other pair of gripper arms is also actuated in unison such that they operate as a respective single arm. This way, the robotic gripper 200 operates as a two-finger gripper.

[0089] Figure 11 illustrates a perspective view of the robotic gripper 200 operating in a two- finger configuration, Figure 12 illustrates a top view of the robotic gripper 200 operating in the two-finger configuration, in accordance with an example implementation. As shown in Figure 12, the angular drive gear 374 of the gripper arm assembly 208 can be driven clockwise (from the perspective of the top view of Figure 12) or the angular drive gear 390 of the gripper arm assembly 210 can be driven counter-clockwise (from the perspective of the top view of Figure 12), thereby rotating the gripper arm assembly 208 and the gripper arm assembly 210 toward each other until they are parallel. Similarly, the angular drive gear 338 of the gripper arm assembly 204 can be driven clockwise (from the perspective of the top view of Figure 12) or the angular drive gear 358 of the gripper arm assembly 206 can be driven counter-clockwise (from the perspective of the top view of Figure 12), thereby rotating the gripper arm assembly 204 and the gripper arm assembly 206 toward each other until they are parallel.

[0090] The gripper arms 360, 376 can then be controlled in tandem such that the gripper arms 360, 376 move in unison as if they are one larger arm. In other words, the same command is sent to the actuators of the arm linkages 362, 378 and actuators of the fingers 364, 380 so the gripper arms 360, 376 move as one gripper arm. Also, the gripper arms 300, 344 can be controlled in tandem such that the gripper arms 300, 344 move in unison as if they are one larger arm. In other words, the same command is sent to the actuators of the arm linkages 302, 346 and actuators of the fingers 304, 348 so the gripper arms 300, 344 move as one gripper arm. As such, the robotic gripper 200 operates in a two-finger configuration.

[0091] In another example, a particular item is best picked by a suction cup only, without fingers. The robotic gripper 200 is configured to operate in a vacuum-only configuration. Particularly, in such configuration, the gripper arms 300, 344, 360, and 376 are retracted and the suction cup 394 is then used to pick the item.

[0092] Figure 13 illustrates a perspective view of the robotic gripper 200 operating in a vacuum- only configuration, Figure 14 illustrates a side view of the robotic gripper 200 operating in the vacuum-only configuration, in accordance with an example implementation. As shown in Figures 13-14, the arm drive input shafts 330, 354, 370, and 386 are driven such that the gripper arms 300, 344, 360, and 376 retract (i.e., the arm linkages 302, 346 rotate counter-clockwise and the arm linkages 362, 378 rotate clockwise from the perspective of the side view of Figure 14). This way, the gripper arms 300, 344, 360, and 376 do not obstruct the suction cup 394, which can then be moved toward an object to be picked. Vacuum can be generated as described above, and the object is attracted, and sticks, to the suction cup 394.

[0093] Thus, the robotic gripper 200 can operate in a four-finger configuration (Figures 2-4), a three-finger configuration (Figures 9-10), a two-finger configuration (Figures 11-12), and a vacuum-only configuration (Figures 13-14). Further, other unique configurations can be achieved. For example, two gripper arms can be rotated by their respective angular drive gear such that they cross a center of the base plate 202 and join the other two gripper arms such that all four gripper arms are disposed on the same side of the base plate 202. In other words, all four gripper arms (i.e., the gripper arms 300, 344, 360, and 376) can be facing outward from one side of the base plate 202 and operate as four human fingers, whereas the suction cup 394 operate as a human thumb. As such, the robotic gripper 200 operate in a human hand-like configuration.

[0094] In another example, any of the fingers 304, 348, 364, and 380 can be rotate over-center about its respective finger pivot pin (e.g., the finger 304 can rotate over-center about the finger pivot pin 305) and the finger can then be pushed outward to enter a can or hollow cylinder to perform a task.

[0095] The versatility and various configurations in which the robotic gripper 200 can operate facilitate pick a variety of items in a high-mix environment. In some instance, the robotic gripper 200 can operate in a first configuration initially to perform an initial operation, then switch to a different configuration to complete the picking operation. To illustrate the versatility and adaptability of the robotic gripper 200, Figures 15, 16, and 17 illustrate the process of picking a book, and Figure 18 illustrates the process of picking a wine glass. [0096] Figure 15 illustrates operating the robotic gripper 200 initially in a vacuum-only configuration to attach to a book 400 and raise the book 400 from a binding side 402, Figure 16 illustrate operating the robotic gripper 200 in a three-finger configuration and using two combined arms to provide support for the book 400, and Figure 17 illustrate using the other two fingers to stabilize and complete picking operation of the book 400, in accordance with an example implementation.

[0097] The robot 100 may have a vision system or other sensory system that enables a controller of the robot 100 to identify the binding side 402 of the book 400. The robot 100 then operates the robotic gripper 200 in a vacuum-only configuration (see Figures 13-14 described above). The robot 100 then moves the robotic gripper 200 to position the suction cup 394 on a front cover of the book 400 proximate the binding side 402.

[0098] The vacuum generating device can then be activated to apply a suction force on the book 400 so the book 400 attaches to the suction cup 394. The robot 100 can then lift the robotic gripper 200 along with the book 400 attached thereto such that the binding side 402 of the book 400 is raised, while the other side of the book may still be resting on a surface 404 as shown in Figure 16.

[0099] The robot 100 then operates the robotic gripper 200 in a three-finger configuration (see Figures 9-10 and description above) where the gripper arms 360, 376 are combined to operate as one large arm. The fingers 364, 380 are then inserted underneath the book 400 to provide support thereto. The fingers 304, 348 can then also be made to contact the other side of the book 400.

[00100] Once the fingers 364, 380 are inserted sufficiently underneath the book 400, the robotic gripper 200 can lift the book 400 off the surface 404 and stabilize the book 400 horizontally using the suction cup 394, the fingers 364, 380, and the fingers 304, 348 as shown in Figure 17. This process can be used even if the book 400 is placed within a bin.

[00101] As described above, the finger drive input shafts (e.g., the finger drive input shaft 318) and the arm drive input shafts (e.g., the arm drive input shaft 330) are configured to drive respective worm gears (e.g., the finger drive worm gear 322, and the arm drive worm gear 334) that in turn drive worm wheels (e.g., the finger drive worm wheel 324 and the arm drive worm wheel 336). Advantageously, the worm gear arrangement described above prevents the input shafts and the actuators driving them from being back-driven by gravity or other forces. Particularly, the friction between the worm gears and the worm wheels prevents the worm wheels from applying a force to the worm gear engaging therewith that would cause the worm gears to rotate backward. As such, even if power is lost to the robot 100, the object (e.g., the book 400) being handled by the robotic gripper 200 may stay in position supported by the robotic gripper 200 rather than being dropped.

[00102] Figure 18 illustrates picking a wine glass 500, in accordance with an example implementation. Initially, the robot 100 operates the robotic gripper 200 in a four-finger configuration (see Figures 2-4) and move the robotic gripper 200 close to the wine glass 500 such that a stem 502 of the wine glass 500 is positioned between the fingers 364, 380. The robot 100 can then operate the robotic gripper 200 in a three-finger configuration where the gripper arms 360, 376 are combined to operate as one large arm with the stem 502 squeezed lightly between the fingers 364, 380. The robot 100 can then move the fingers 304, 348 toward a body 504 of the wine glass to grip the wine glass 500. The wine glass 500 can then be moved where desired. [00103] Several variations can be implemented to the robotic gripper 200. For example, rather than using worm gears and worm wheels, other types of gears could be used (e.g., spur gears, helical gears, etc.). In other examples, belts or chains could be used instead of gears. Various types of actuators could be used to actuate or move the arm linkages, fingers, and rotate the arm pivot brackets. Also, although the robotic gripper 200 is illustrates in the figures as having four gripper arms, in other examples, fewer or more gripper arms and arm assemblies can be used.

[00104] Further, the gripper arm assemblies 204, 206, 208, 210 are described herein as being identical, with each gripper arm assembly having a respective arm pivot bracket rotatably coupled to the base plate, a respective arm linkage pivotably coupled to the respective arm pivot bracket, and a respective finger pivotably coupled to the respective arm linkage. However, in other example implementation, the gripper arm assemblies may differ. For instance, one or more gripper arm assemblies may have three degrees of freedom as described herein, whereas one or more of the remaining gripper arm assemblies may have a reduced number of degrees of freedom or can be configured with different components, gear types, etc.

[00105] In an example, it may be desirable to configure the fingers of a robotic gripper (e.g., robotic gripper 200) such that the fingers can adapt or conform to a shape of an object, thereby enabling the robotic gripper to pick object with various geometries. It may be further desirable to configure the fingers of the robotic gripper with a force sensor to indicate the gripping force being applied by the fingers to the object or, if the fingers are carrying an object, indicate the weight of the object.

[00106] Described herein is an example implementation of a finger having a plurality of pins, or more particularly a matrix of spring-loaded pins. The matrix of spring-loaded pins can adapt and conform to a geometry of the object being gripped. In an example implementation, the finger also has a force sensor (e.g., a load cell) that provides an indication of the load that the finger applies or the weight that it carries. The disclosed finger can be used with, but is not limited to, the robotic gripper 200 described above, for example. It should be understood that the configuration of the finger can be used with any other robotic gripper.

[00107] Figures 19-26 illustrates an example implementation of a finger 600. Particularly, Figure 19 illustrates a perspective view of the finger 600, Figure 20 illustrates a top view of the finger 600, Figure 21 illustrates a side view of the finger 600, Figure 22 illustrates a front view of the finger 600, Figure 23 illustrates a rear view of the finger 600, and Figure 24 illustrates a bottom view of the finger 600, in accordance with an example implementation. The finger 600 can represent, for example, any of the fingers 304, 348, 364, and 380 described above. However, the finger 600 can represent any finger of a robotic gripper.

[00108] The finger 600 can be pivotably-coupled to an arm linkage of an arm assembly via a finger pivot pin 602 mounted at a joint between the finger 600 and the arm linkage. For example, assuming the finger 600 represents the finger 304 described above, the finger pivot pin 602 represents the finger pivot pin 305, and the finger 600 can be pivotably-coupled to the arm linkage 302 via the finger pivot pin 602.

[00109] The finger 600 includes a plurality of pins comprising a matrix 604 of spring-loaded pins. In the example implementation of Figures 19-24, the matrix 604 includes five rows of pins, each row including four pins. The matrix 604 further includes a sixth row having three pins and a seventh row having two pins. The sixth and seventh row have fewer pins to accommodate a tapered portion 605 of the finger 600. This configuration is an example for illustration. More or fewer pins and rows thereof can be used based on a size of the finger and the application in which the robotic gripper is to be used. [00110] Figure 25 illustrates another top view of the finger 600 in another orientation, and Figure 26 illustrates a cross-sectional view of the finger 600, in accordance with an example implementation. The cross-sectional view of Figure 26 is taken along a plane labelled in Figure 25.

[00111] The cross-sectional view of Figure 26 shows four pins of the matrix 604: a pin 606, a pin 608, a pin 610, and a pin 612. The pin 606 is described next, and the pins 608, 610, 612 can be configured similarly.

[00112] The pin 606 has a pin body 614 having a pin body tip 616. The pin body 614 can be made of a rigid material (e.g., a metallic material such as steel). In an example, the pin body tip 616 can take the shape of an I-beam (e.g., two horizontal flanges that are connected by a vertical connection) to facilitate over molding a pin tip 618. The pin body tip 616 can take any other shape that facilitates or improve adhesion of an over-molded pin tip (e.g., the pin tip 618).

[00113] In an example, the pin tip 618 can be made of an elastic material, whereas the pin body 614 is made of a harder material (i.e., a material that has a higher hardness) than the elastic material of the pin tip 618. For example, the pin tip 618 can be a rubber over-molded pin tip. When the robotic gripper grips or carries an object, it contacts the object via the pin tip 618. Advantageously, due to being made of an elastic material, the pin tip 618 may avoid damaging or deforming the object. Further, the pin tip 618 may add friction to improve traction and grip- ability as the finger 600 contacts the object to grip it.

[00114] In another example implementation, the pins, such as the pin 606 can be made of a single or unitary piece (i.e., the pin body 614 and the pin tip 618 can be combined into a single body). For instance, for applications involving lighter forces, the pins, e.g., the pin 606, can be a single body made of a plastic material. [00115] The matrix 604 of pins are retained by a pin housing 620. As depicted, the pins 606-612 are partially disposed in pin housing 620 such that a portion of each pin protrudes outward from the pin housing 620 to interact with objects to be gripped by the finger 600. As described below, the pin housing 620 operates as a bushing or a plain bearing that allows the pins to slide or reciprocate axially along their axes when they interact with an object.

[00116] The pin 606 has a pocket or cavity 622 at the pin end opposite the pin tip 618. The cavity 622 receives a first end of a spring 624. The pin body 614 has a protrusion 625 that protrudes in the cavity 622, and the spring 624 is disposed partially about the exterior surface of the protrusion 625. With this configuration, the first end of the spring 624 is retained and guided within the cavity 622. Particularly, the exterior surface of the spring 624 is guided by the interior surface of the pin 606, and the interior surface of the spring 624 is guided by the protrusion 625.

[00117] The finger 600 further includes a spring plate 626 disposed within the pin housing 620 and configured to accommodate the second end of the spring 624. Particularly, the spring plate 626 has a respective pocket or respective cavity 628 that receives the second end (i.e., opposite end) of the spring 624. With this configuration, the spring 624 is retained between the pin 606 and the spring plate 626 such that the spring 624 is disposed partially in the cavity 622 of the pin 606 and disposed partially in the respective cavity 628 of the spring plate 626. As depicted, the spring plate 626 has similar cavities to accommodate respective springs of the pins 608, 610, 612.

[00118] Also, with this configuration, the spring 624 applies a biasing force on the pin 606 in an outward direction (e.g., upward in Figure 26). The pin body 614 has a flanged portion 630 that interfaces with or rests against a shoulder 632 made by the interior surface of the pin housing 620 to limit the extent to which the pin 606 moves outward. As such, the pin 606 is spring- loaded and biased to the position shown in Figure 26 when the finger 600 is not in contact with an object. When the finger 600 grips an object (along with another opposing finger of another arm of the robotic gripper), at least a subset of pins of the matrix 604 engages the object and are pushed inward to accommodate it, thereby compressing their respective springs. When the object is released, the springs bias the pins back to their position shown in Figure 26.

[00119] In an example, the finger 600 can further include a back plate 634 that is rigid. Referring to Figures 21, 24 and 26, the back plate 634 can be coupled to the pin housing 620 via a plurality of fasteners such as fastener 636.

[00120] Also, in an example implementation, as shown in Figure 26, the finger 600 can include a force sensor such as a load cell 638 interposed between the spring plate 626 and the back plate 634. The load cell 638 is configured as a force transducer that converts compressive forces, pressure, or torque applied thereto into an electrical signal. As the force applied to the load cell 638 increases, the electrical signal changes proportionally. Other types of force or pressure sensors can be used, such as strain gauges.

[00121] As the pins of the matrix 604 are compressed, they apply a force to the load cell 638 via the spring plate 626. The spring plate 626 and the back plate 634 are rigid and operate as non- deformable surfaces against which the load cell 638 reacts to measure the force being applied to the load cell 638.

[00122] In operation, the controller of the robotic gripper can move the robotic gripper to a location of an object (e.g., the book 400 of the wine glass 500). The controller can then command the actuators of the robotic gripper to move the fingers, such as the finger 600, toward the object to grip it. As the finger 600 contacts the object, at least a subset of the pins of the matrix 604 engages or contacts the object. Advantageously, the matrix 604 of pins adapts or conforms to the shape of the object (i.e., the number of pins that engage the object, and the extent of linear movement of the pins is such that the matrix 604 of pins adapts to the shape of the object).

[00123] As the finger 600 moves further toward the object to apply a sufficient gripping force thereto, the pins are pushed inward and compress their respective springs (e.g., the pin 606 compresses the spring 624). As the springs of the pins are compressed, the compressive force is transferred to the spring plate 626, which in turn squeezes the load cell 638 against the back plate 634. As such, the load cell 638 can generate an electric signal indicative of the magnitude of the force being applied to, which is indicative of the grip strength or force that the finger 600 applies to the object.

[00124] The pin housing 620 operates a bushing for the pins of the matrix 604 and for the spring plate 626. Particularly, the pin housing 620 can be made of a bushing material (e.g., graphite, urethane, polyoxymethylene, etc.), and thus the interior surface of the pin housing 620 operates as a lubricated plain bearing surface that allows components to slide therealong. As such, the pin housing 620 facilitates linear movement of the pins (e.g., the pin 606) as the finger 600 presses against the object, and the object moves the pins inward.

[00125] Further, the pin housing 620 advantageously may cause the load cell 638 to be loaded uniformly regardless of which pins of the matrix 604 are in contact with or engaging the object. For example, an object may have a particular shape that, when the finger 600 approaches and engages the object, causes the pin 606 to move inward, compressing the spring 624, whereas the other pins 608, 610, and 612 do not contact the object. It might not be desirable to have the spring plate 626 being side-loaded by the pin 608, because such side loading may cause the load cell 638 to provide an inaccurate force measurement. The interior surface of the pin housing 620 acting as a lubricated bushing surface for both side exterior surfaces of the spring plate 626 (which interface with the interior surface of the pin housing 620) advantageously may cause the spring plate 626 to apply a uniform load (e.g., straight load) on the load cell 638 despite being loaded on one side by the pin 606 and not the other pins.

[00126] As the finger 600 squeezes the object (against another finger of the robotic gripper), the load cell 638 is in turn squeezed between the spring plate 626 and the back plate 634, and the load cell 638 can thus provide to the controller of the robotic gripper an electric signal indicative of the force that the finger 600 applies to the object (i.e., the gripping force being applied to the object). The controller can responsively determine the extent with which to move the finger 600 toward the object, i.e., the amount of squeezing to apply to the object to avoid damaging the object.

[00127] Each object may tolerate a particular gripping force before being damaged. For example, fruit (e.g., apple, tomato, avocado, etc.) may tolerate a small gripping force (e.g., 1 lbf), while another more rigid object, such as the wine glass 500, may tolerate a larger gripping force (e.g., 2 lbf). Thus, the controller identifies the type of the object and monitors the signal received from the load cell 638 to determine when to stop squeezing the object to achieve sufficient gripping strength without damaging the object. For instance, for fruit, once the load cell 638 indicates that the force is approaching a threshold force (e.g., 1 lbf), the controller may stop the finger 600 from squeezing the object further to avoid damaging it.

[00128] In another example, rather than gripping or squeezing an object, the robotic gripper may be carrying an object (e.g., the book 400) from one location to another. In this example, the load cell 638 provides a force measurement indicative of a weight of the object to the controller. [00129] In another example implementation, the finger 600 might not have the force sensor or load cell 638. In this example implementation, the spring plate 626 and the back plate 635 can be combined into a single plate (or the spring plate 626 can be eliminated) having cavities, such as the respective cavity 628, for the respective springs. As such, it should be understood that the force sensor is an optional feature.

[00130] The detailed description above describes various features and operations of the disclosed systems with reference to the accompanying figures. The illustrative implementations described herein are not meant to be limiting. Certain aspects of the disclosed systems can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein.

[00131] Further, unless context suggests otherwise, the features illustrated in each of the figures may be used in combination with one another. Thus, the figures should be generally viewed as component aspects of one or more overall implementations, with the understanding that not all illustrated features are necessary for each implementation.

[00132] Additionally, any enumeration of elements, blocks, or steps in this specification or the claims is for purposes of clarity. Thus, such enumeration should not be interpreted to require or imply that these elements, blocks, or steps adhere to a particular arrangement or are carried out in a particular order.

[00133] Further, devices or systems may be used or configured to perform functions presented in the figures. In some instances, components of the devices and/or systems may be configured to perform the functions such that the components are actually configured and structured (with hardware and/or software) to enable such performance. In other examples, components of the devices and/or systems may be arranged to be adapted to, capable of, or suited for performing the functions, such as when operated in a specific manner.

[00134] By the term “substantially” or “about” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[00135] The arrangements described herein are for purposes of example only. As such, those skilled in the art will appreciate that other arrangements and other elements (e.g., machines, interfaces, operations, orders, and groupings of operations, etc.) can be used instead, and some elements may be omitted altogether according to the desired results. Further, many of the elements that are described are functional entities that may be implemented as discrete or distributed components or in conjunction with other components, in any suitable combination and location.

[00136] While various aspects and implementations have been disclosed herein, other aspects and implementations will be apparent to those skilled in the art. The various aspects and implementations disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the following claims, along with the full scope of equivalents to which such claims are entitled. Also, the terminology used herein is for the purpose of describing particular implementations only, and is not intended to be limiting.

[00137] Implementations of the present disclosure can thus relate to one of the enumerated example implementation (EEEs) listed below. [00138] EEE 1 is a finger of a robotic gripper, the finger comprising: a pin housing; a plurality of pins disposed partially in the pin housing, each pin being configured to be movable within the pin housing; a spring plate, wherein each pin of the plurality of pins is spring-loaded by a spring disposed between the pin and the spring plate; a back plate coupled to the pin housing; and a force sensor interposed between the spring plate and the back plate, such that when a subset of pins of the plurality of pins contact an object, the subset of pins move within the pin housing against respective springs associated with the subset of pins, and the force sensor provides an electric signal indicative of a force applied by the subset of pins to the object.

[00139] EEE 2 is the finger of EEE 1, wherein each pin has a cavity, and wherein the spring plate has a respective cavity corresponding to the cavity of the pin, and wherein the spring associated with the pin is disposed partially in the cavity of the pin and partially in the respective cavity of the spring plate.

[00140] EEE 3 is the finger of EEE 2, wherein the pin has a pin body having a protrusion protruding in the cavity of the pin to operate as a guide for the spring.

[00141] EEE 4 is the finger of any of EEEs 1-3, wherein each pin has a pin body having a flanged portion, wherein the pin housing has a shoulder, and wherein the spring biases the pin such that the flanged portion of the pin contacts the shoulder until the pin contacts the object.

[00142] EEE 5 is the finger of EEE 4, wherein the pin further comprises a pin tip coupled to the pin body, wherein the pin tip is made of an elastic material, and wherein the pin body is made of a material that is harder than the elastic material of the pin tip.

[00143] EEE 6 is the finger of any of EEEs 1-5, wherein an exterior surface of the pin interfaces with and slides along an interior surface of the pin housing when the pin contacts the object. [00144] EEE 7 is the finger of any of EEEs 1-6, wherein a side exterior surfaces of the spring plate interfaces with an interior surface of the pin housing, which operates as a plain bearing for the spring plate.

[00145] EEE 8 is a robotic gripper comprising: a plurality of gripper arm assemblies, wherein a gripper arm assembly of the plurality of gripper arm assemblies comprises: an arm linkage and a finger pivotably coupled to the arm linkage, and wherein the finger comprises: a pin housing, a plurality of pins disposed partially in the pin housing, each pin being configured to be movable within the pin housing, a spring plate, wherein each pin of the plurality of pins is spring-loaded by a spring disposed between the pin and the spring plate, a back plate coupled to the pin housing, and a force sensor interposed between the spring plate and the back plate, such that when a subset of pins of the plurality of pins contact an object, the subset of pins move within the pin housing against respective springs associated with the subset of pins, and the force sensor provides an electric signal indicative of a force applied by the subset of pins to the object.

[00146] EEE 9 is the robotic gripper of EEE 8, wherein each pin has a cavity, and wherein the spring plate has a respective cavity corresponding to the cavity of the pin, and wherein the spring associated with the pin is disposed partially in the cavity of the pin and partially in the respective cavity of the spring plate.

[00147] EEE 10 is the robotic gripper of EEE 9, wherein the pin has a pin body having a protrusion protruding in the cavity of the pin to operate as a guide for the spring.

[00148] EEE 11 is the robotic gripper of any of EEEs 8-10, wherein each pin has a pin body having a flanged portion, wherein the pin housing has a shoulder, and wherein the spring biases the pin such that the flanged portion of the pin contacts the shoulder until the pin contacts the object. [00149] EEE 12 is the robotic gripper of EEE 11, wherein the pin further comprises a pin tip coupled to the pin body, wherein the pin tip is made of an elastic material, and wherein the pin body is made of a material that is harder than the elastic material of the pin tip.

[00150] EEE 13 is the robotic gripper of any of EEEs 8-12, wherein an exterior surface of the pin interfaces with and slides along an interior surface of the pin housing when the pin contacts the object.

[00151] EEE 14 is the robotic gripper of any of EEEs 8-13, wherein a side exterior surfaces of the spring plate interfaces with an interior surface of the pin housing, which operates as a plain bearing for the spring plate.

[00152] EEE 15 is a robot comprising: a robot arm; and a robotic gripper coupled to the robot arm, wherein the robotic gripper comprises a plurality of gripper arm assemblies, wherein a gripper arm assembly of the plurality of gripper arm assemblies comprises: an arm linkage and a finger pivotably coupled to the arm linkage, and wherein the finger comprises: a pin housing, a plurality of pins disposed partially in the pin housing, each pin being configured to be movable within the pin housing, a spring plate, wherein each pin of the plurality of pins is spring-loaded by a spring disposed between the pin and the spring plate, a back plate coupled to the pin housing, and a force sensor interposed between the spring plate and the back plate, such that when a subset of pins of the plurality of pins contact an object, the subset of pins move within the pin housing against respective springs associated with the subset of pins, and the force sensor provides an electric signal indicative of a force applied by the subset of pins to the object.

[00153] EEE 16 is the robot of EEE 15, wherein each pin has a cavity, and wherein the spring plate has a respective cavity corresponding to the cavity of the pin, and wherein the spring associated with the pin is disposed partially in the cavity of the pin and partially in the respective cavity of the spring plate.

[00154] EEE 17 is the robot of EEE 16, wherein the pin has a pin body having a protrusion protruding in the cavity of the pin to operate as a guide for the spring.

[00155] EEE 18 is the robot of any of EEEs 15-17, wherein each pin has: a pin body having a flanged portion, wherein the pin housing has a shoulder, and wherein the spring biases the pin such that the flanged portion of the pin contacts the shoulder until the pin contacts the object; and a pin tip coupled to the pin body, wherein the pin tip is made of an elastic material, and wherein the pin body is made of a material that is harder than the elastic material of the pin tip.

[00156] EEE 19 is the robot of any of EEEs 15-18, wherein an exterior surface of the pin interfaces with and slides along an interior surface of the pin housing when the pin contacts the object.

[00157] EEE 20 is the robot of any of EEEs 15-19, wherein a side exterior surfaces of the spring plate interfaces with an interior surface of the pin housing, which operates as a plain bearing for the spring plate.