SYSTEMS AND METHODS FOR DETECTING AND MOVING OBJECTS

Description

BACKGROUND

[0001] The invention generally relates to programmable motion systems and relates in particular to end effectors for programmable motion devices (i.e., robotic systems) for use in object processing such as object sortation.

[0002] End effectors for robotic systems, for example, may be employed in certain applications to select and grasp an object, and then move the acquired object very quickly to a new location. End effectors that are designed to very securely grasp an object during movement may have limitations regarding how quickly and easily they may select and grasp an object from a jumble of dissimilar objects. Conversely, end effectors that may quickly and easily grasp a selected object from a jumble of dissimilar objects may have limitations regarding how securely they may grasp an acquired object during rapid movement, particularly rapid acceleration and deceleration (both angular and linear).

[0003] Many end effectors employ vacuum pressure for acquiring and securing objects for transport or subsequent operations by articulated arms. Other techniques for acquiring and securing objects employ electrostatic attraction, magnetic attraction, needles for penetrating objects such as fabrics, fingers that squeeze an object, hooks that engage and lift a protruding feature of an object, and collets that expand in an opening of an object, among other techniques. Typically, end effectors are designed as a single tool, such as for example, a gripper, a welder, or a paint spray head, and the tool is typically designed for a specific set of needs.

[0004] There remains a need therefore, for an end effector in a programmable motion system that may select and grasp an object, and then move the acquired object very quickly to a new location.

[0005] US 6846029 discloses a device for gripping, holding, and releasing objects of varying sizes and shapes, which comprises an elongated torus enclosing a fluid material, an external control rod and an internal control rod. Also disclosed is a gripper with an elongated torus being driven (actuated) by a roller assembly. The roller assembly is stationary in this design and mounted to a storage bin. For use on a robotic arm, a bracket can be used to bolt the gripper to the end of the mechanical arm (robotic arm).US 4243040 discloses an extracting device, useful for removing kidney stones, comprising a thin tubular rubber sleeve having its proximal and distal ends connected to the distal ends of outer and inner flexible tubes insertable into the body passage.SUMMARY

[0006] In accordance with another embodiment, the invention provides an end effector system according to appended claim 1. The end effector system includes a primary acquisition system that includes a primary end effector, and a secondary retention system proximate to the primary gripper system such that the primary end effector system may be used to select an object from a plurality of objects, and the secondary retention system may be used to retain the object for rapid transport to an output destination.

[0007] In accordance with a further embodiment, the invention provides a method according to appended claim 8 of engaging and moving an object using a robotic system. The method includes the steps of engaging the object with a primary end effector of a primary acquisition system, moving the object toward a secondary retention system, retaining the object with the secondary retention system, and transporting the object to an output destination.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The following description may be further understood with reference to the accompanying drawings in which: Figure 1 shows an illustrative diagrammatic view of a system; Figure 2 shows an illustrative diagrammatic view of an end effector portion of the system of Figure 1; Figures 3A - 3C show illustrative diagrammatic sectional views of the end effector portion including a tubular annulus during acquisition and retention of an object; Figures 4A - 4D show illustrative diagrammatic sectional views of the end effector portion including a jamming gripper during acquisition and retention of an object; Figures 5A - 5C show illustrative diagrammatic sectional views of the end effector portion including vacuum cups during acquisition and retention of an object; Figures 6A - 6D show illustrative diagrammatic sectional views of the end effector portion including gripping retention actuators during acquisition and retention of an object; Figures 7A and 7B show illustrative diagrammatic sectional views of the end effector portion including a retention shroud during acquisition and retention of an object; Figures 8A and 8B show illustrative diagrammatic sectional views of the end effector portion including further gripping retention actuators during acquisition and retention of an object; Figures 9A and 9B show illustrative diagrammatic sectional views of the end effector portion including a further arrangement of vacuum cups during acquisition and retention of an object; Figures 10A and 10B show illustrative diagrammatic sectional views of the end effector portion including retention stabilizing pads during acquisition and retention of an object; Figure 11 shows an illustrative diagrammatic view of a system in accordance with an embodiment of the present invention that includes a retention tray; Figure 12A - 12F show illustrative diagrammatic sectional views of the end effector portion in accordance with an embodiment including a retention tray during acquisition, retention and release of an object; Figure 13 shows an illustrative diagrammatic view of a system that includes a retention support; Figures 14A and 14B show illustrative diagrammatic sectional views of the end effector portion including a retention support during acquisition, retention and release of an object; Figure 15 shows an illustrative diagrammatic view of the end effector system of Figure 13 approaching a jumble of objects; Figures 16A and 16B show illustrative diagrammatic sectional views of the end effector portion of Figure 15 including a retention support during acquisition and retention of an object; Figure 17 shows an illustrative diagrammatic view of a system that includes multiple vacuum cups; Figures 18A and 18B show illustrative diagrammatic sectional views of the end effector portion including multiple vacuum cups during acquisition and retention of an object; and Figures 19A and 19B show illustrative diagrammatic sectional views of the end effector portion employing positive air pressure to create a vacuum at the end effector.

[0009] The drawings are shown for illustrative purposes only.DETAILED DESCRIPTION

[0010] In accordance with various embodiments, the invention provides end effector systems that include two elements, one element for acquisition, and one element for secure holding during transportation. The acquisition element may be specialized to address challenges of acquisition, which may include perception of a desired object, separating the object from supporting or surrounding objects, and shifting the object to a position and orientation suited for transportation.

[0011] The secure holding element may be specialized to address challenges of transportation, which may include security and stability during transport, despite gravitational forces, high speed acceleration, centrifugal forces, and contact with surrounding objects.

[0012] Generally and in certain embodiments, the invention provides an end effector system for a robotic system, e.g., an articulated arm robotic system or any of a delta, gantry, spherical, SCARA, or cylindrical robotic systems. The end effector system includes a primary gripper system and a secondary retention system that substantially surrounds at least a portion of the primary gripper system. In certain embodiments, at least a portion of the primary gripper system may be drawn up within at least a portion of the secondary retention system such that the primary gripper system may be used to select an object from a plurality of objects, and the secondary retention system may be used to secure the object for rapid transport to an output destination.

[0013] More generally, and in accordance with a further embodiment, the invention provides a method of engaging and moving an object using a robotic system. The method includes the steps of engaging the object with a primary gripper system, moving the object toward a secondary retention system, retaining the object with the secondary retention system, and transporting the object to an output destination.

[0014] Figure 1 shows a robotic system 10 that includes an articulated arm 12 on a base 14, and an end effector system 16. As further shown in Figure 2, the end effector system may attach to the articulated arm 12 by way of an engagement feature 18 (such as threads, spring-loaded clasp, or ball and socket engagement) that mate with an engagement feature on the articulated arm 12, and further, the end effector system may include a primary gripper system including a gripper on the end of an extender 20, as well as secondary retention system 24 as discussed in more detail below. As each of the acquisition element and the secure holding element may vary, and many different embodiments are possible. The gripper in each of the embodiments, for example, may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc.

[0015] Figures 3A - 3C diagrammatically show sectional views of an end effector system 30 that includes a primary gripper system including a gripper 32 on the end of an extender 34. The end effector system 30 also includes a secondary retention system including a flexible toroid 36.

[0016] The flexible toroid is a fluid-filled or powder filled (and optionally elastic) flexible membrane that is compressed and inverted as it is drawn into the center of the supporting structure. Such a device is formed of a continuous sheet of fabric that is in the form of a torus, or an annulus that extends along the direction that extends through the center of the annulus.

[0017] As shown in Figure 3A, a portion of the outer surface of the flexible toroid 36 is attached to the inner surface of the housing 38 as shown at 40, and a portion of the inner surface of the elastic toroid is attached to the extender at 41. The toroid is able to move up and down (by rolling) between the outer collar and the inner extender.

[0018] With reference to Figure 3B, the extender 34 may be moved in the direction as indicated at A such that the vacuum gripper 32 engages an object to be grasped 42. By supplying a vacuum source through the extender 34, the object may be engaged. As further shown in Figure 3B, when the extender 34 is moved in the direction as indicated at A, it draws the inner surface of the elastic toroid with it, which causes one end of the elastic toroid to roll inward upon itself in direction A, while the opposing end of the elastic toroid will roll outward. While the elastic toroid 36 undergoes this process of everting, it remains attached to the housing 38 at the attachment 40.

[0019] As shown in Figure 3C, when the engaged object is pulled into the elastic toroid, the object is securely engaged for transport or other processing operations. By controlling the movement of the elastic toroid as described above, the end effector may be used to draw the object 42 into the elastic toroid and hold it within the elastic toroid until the linear actuator is moved in a direction that is opposite the direction indicated at A (and the object 42 is discharged). The elastic toroid is formed of a flexible material that may conform to the shape of the object 42 being grasped. The fluid (or powder) within the elastic toroid may be water (or plastic particles) or may be selected to have a particular viscosity.

[0020] As shown in Figures 4A - 4C (which show diagrammatic sectional views), an end effector system 50 includes a primary gripper system including a gripper 52 on the end of an extender 54. The end effector system 50 also includes a secondary retention system including a jamming gripper 56 having one or more vacuum attachment ports 58. Generally, the jamming gripper encloses a fluid or volume of particles having a very small size (e.g., powder) such that when a vacuum source is provided to the ports 58, the jamming gripper 56 reduces its volume and grabs any object within its outer edge. The jamming gripper 56 is also attached to the interior of the housing 60 as shown at 62.

[0021] As shown in Figure 4B, the extender 54 may be extended, permitting the gripper 54 to engage an object 64, and as shown in Figure 4C, when the object is drawn up near or into the jamming gripper 56, the jamming gripper engages at least a portion of the outer surface of the object 64. As shown in Figure 4D, when the vacuum source is applied to the jamming gripper 56, the gripper 56 conforms to the surface of the object 64, thereby securing the object 56 for transport or other processing operations.

[0022] In each of the embodiments of Figure 3A - 4D, the secondary retention system may have difficulty engaging an object from an input area, but when combined with the primary gripper system, the end effector systems may acquire an object and subsequently securely retain the object, even when the end effector system undergoes rapid linear and angular acceleration or deceleration.

[0023] As shown in Figures 5A - 5C (which show diagrammatic sectional views), an end effector system 70 includes a primary gripper system including a gripper 72 on the end of an extender 74. The gripper 72 may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc. The end effector system 70 also includes a secondary retention system including a large area gripper 76 (e.g., a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc.) that surrounds the extender 74. As shown in Figure 5B, when the gripper 72 is extended into a cluttered environment (including, e.g., objects 80, 82, 84), the gripper 72 may engage an object 82, and draw the object toward the large area gripper 76, which then surrounds the gripper 72. The large area gripper 76 is then employed during rapid transport or further processing operations.

[0024] Figures 6A - 6D show a diagrammatic sectional view of an end effector system 90, which includes a primary gripper system including a gripper 92 on the end of an extender 94. The gripper 92 may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc. The end effector system 90 also includes a secondary retention system including two or more constricting actuators 96 (e.g., pinch grippers), that may be rotated with respect to pivot locations 98 such that a portion of each actuator 96 may engage a portion of an object to thereby secure the object.

[0025] In particular, as shown in Figure 6B, the actuator 92 may be extended to engage an object such as a bag 100 that includes loose items 102. As shown in Figures 6C and 6D, the bag 100 may be acquired by the gripper 92, and the constricting actuators 96 may then be rotated to secure the bag 100 within the end effector system 90.

[0026] Figures 7A and 7B show an end effector 110 that includes a first portion 112 having a vacuum cup that may be actuated to engage an object 114, and then may withdraw the grasped object within a second portion 116 in the form of a shroud. In various embodiments, the first portion 112 may move toward the object while the shroud 116 remains fixed, or in other embodiments, the first portion may be fixed, and the shroud 116 may be actuated to move toward the object 114 once grasped.

[0027] Figures 8A and 8B show an end effector 120 that includes a first portion 122 having a vacuum cup that may be actuated to engage an object 124, and then may withdraw the grasped object 124. A second portion 126 that includes two or more paddles 128 then move radially inward as shown at A to secure the grasped object 124.

[0028] Figures 9A and 9B show an end effector 130 that includes a first portion 132 having a vacuum cup that may be actuated to engage an object 134. The object 134 is then withdrawn toward a second portion 136 that includes one or more additional vacuum cups 138 (three are shown) to secure the object 134 during transport. In accordance with further embodiments, the first portion 132 may be fixed with respect to an articulated arm, and the second portion 136 may be lowered onto the object 134.

[0029] Figures 10A and 10B show an end effector 140 that includes a first portion 142 having a vacuum cup that may be actuated to engage an object 144. The object 144 is then withdrawn toward a second portion 146 that includes one or more compliant pads 148 to secure the object 144 during transport. In accordance with further embodiments, the first portion 142 may be fixed with respect to an articulated arm, and the second portion 146 may be lowered onto the object 144.

[0030] Figure 11 shows a robotic system 210 in accordance with an embodiment of the invention that includes an articulated arm 212 on a base 114, and an end effector system 216. The end effector system may include a primary gripper system including a gripper 222 on the end of an extender 220, as well as secondary retention system 224 as discussed in more detail below with reference to Figures 12A - 12F. As each of the acquisition element and the transportation element may vary, many different embodiments are possible. The gripper in each of the embodiments, for example, may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc.

[0031] Figures 12A - 12F diagrammatically show views of the end effector system 216 in accordance with an embodiment of the present invention that includes a primary gripper system including the gripper 222 on the end of the extender 220. The secondary retention system 224 includes a suspended cup 226 that may be mounted on an actuated member 228 such that the suspension point of the cup 226 may be moved relative to the base of the end effector system 216.

[0032] As shown in Figures 12A and 12B, the gripper 222 may engage and acquire an object 230, and bring the object 230 toward the suspended cup 226. As shown in Figures 12C and 12D, the end effector 216 may then be rotated, causing the suspended cup to move below the object 230. As shown in Figure 12E, the object 230 may then be dropped into the suspended cup 226. The robotic system may, in certain applications, acquire and place many such objects into a cup prior to transport. Following transport to an output destination, in certain embodiments, the cup 226 may include a releasable bottom 232 that may be actuated to drop the one or more objects into the output destination.

[0033] Figure 13 shows a system 250 that includes an articulated arm 252 on a base 254 as well as an end effector portion 256. The end effector portion 256 includes a primary acquisition portion 258 and a secondary retention system 260. As further shown in Figures 14A and 14B, the primary acquisition system includes a vacuum cup on an actuator shaft 264 that passes through an actuatable magnetic coil within arm 266. The secondary retention system 260 includes a tray for supporting the object 262 once grasped as shown in Figure 14B. As shown in Figure 15, such an end effector portion 256 may also be employed to selectively pull one object (e.g., 270) from a mix of objects 272. As shown in Figures 16A and 16B, the primary acquisition system 258 may acquire the object 270, and the secondary retention system may then support the retained object 270.

[0034] As shown in Figure 17, a system 300 may provide an end effector system that includes a primary acquisition system 302 and a secondary retention system 304, each of which includes a vacuum cup and a pivot joint. When the primary acquisition system 302 engages an object 306 (as shown in Figure 18A), the end effector then rotates (as shown in Figure 18B) such that the secondary retention system 304 also grasp the object 306 so that it may then be lifted and moved (as shown in Figure 18C).

[0035] Again, the gripper attached to the programmable motion extender in each of the embodiments may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc. In other embodiments, both the primary gripper system and the secondary retention system may involve a wide variety of acquisition and retention systems. For example, in accordance with further embodiments, any of the above disclosed systems may be provided with a vacuum source at the end effector wherein the vacuum is provided by a Venturi opening at the end effector. Figures 19A and 19B show an example of a primary retention system 310 (that may be used with any of the above discussed embodiments), and includes a conduit 314 for selectively providing air at positive pressure to an end effector 318. The conduit (which is provided within a second retention system 312 as discussed above), includes an area of restricted diameter 316 as well as a Venturi opening 320. When positive air pressure is provided (as shown in Figure 19B), the air blows out the end of the conduit and produces a vacuum source at the opening 320, thereby permitting the end effector 318 to acquire an object 322. Again, such a positive air pressure and Venturi system for providing the vacuum, may be used with each of the above embodiments.

[0036] Those skilled in the art will appreciate that numerous modifications and variations may be made to the above disclosed embodiments without departing from the scope of the present invention as defined by the appended claims.

Claims

1. An end effector system (216) for attachment to an articulated arm of a robotic system (210), said end effector system (216) comprising: a primary gripper system that includes a gripper (222); and a secondary retention system (224) including a suspended cup (226) proximate to the primary gripper system such that the gripper (222) is configured to acquire an object (230) from a plurality of objects and drop the object (230) into the suspended cup (226) for transport to an output destination.

2. The end effector system (216) as claimed in claim 1, wherein the gripper (222) of the primary gripper system includes a vacuum gripper.

3. The end effector system (216) as claimed in clam 1, wherein the gripper (222) is attached to an end of an extender (224).

4. The end effector system (216) as claimed in claim 3, wherein the suspended cup (226) includes a releasable bottom (232) that is actuated to drop the object (230) into the output destination.

5. The end effector system (216) as claimed in claim 1, wherein the suspended cup (226) is attached to an actuated member (228) such that a suspension point of the cup (226) is movable relative to a base (214) of the end effector system (216).

6. The end effector system (216) as claimed in claim 5, wherein the suspended cup (226) is movable to a position below the object (230) acquired by the gripper (222) prior to the object (230) being dropped into the suspended cup (226).

7. The end effector system (216) as claimed in claim 1, wherein the gripper (222) of the primary gripper system includes any of an electrostatic gripper and a magnetic gripper.

8. A method of engaging and moving an object (230) using a robotic system, said method comprising: acquiring the object (230) with a gripper (222) of a primary gripper system, the primary gripper system being attached to an end effector of an articulated arm of the robotic system; dropping the object (230) from the gripper (222) into a suspended cup (226) of a secondary retention system (224), the secondary retention system (224) also being attached to the end effector; and moving the articulated arm to transport the object (230) in the suspended cup (226) of the secondary retention system (224) to an output destination.

9. The method as claimed in claim 8, further comprising: moving the end effector such that the suspended cup (226) of the secondary retention system (224) moves below the object (230) acquired by the gripper (222); wherein the object (230) is dropped from the gripper (222) of the primary gripper system into the suspended cup (226) once the suspended cup (226) of the secondary retention system (224) is positioned below the object (230).

10. The method as claimed in claim 8, wherein the gripper (222) of the primary gripper system includes a vacuum gripper.

11. The method as claimed in claim 8, wherein the suspended cup (226) of the secondary retention system (224) is attached to the end effector by an actuated member (228) such that a suspension point of the cup (226) is movable relative to a base (214) of the end effector.

12. The method as claimed in claim 8, wherein the method further includes transferring the object (230) from the suspended cup (226) of the secondary retention system (224) to the output destination.

13. The method as claimed in claim 12, wherein the suspended cup (226) of the secondary retention system (224) includes a releasable bottom (232), and wherein the object (230) is transferred from the suspended cup (226) to the output destination by actuating the releasable bottom (232) of the suspended cup (226) to drop the object (230) into the output destination.

14. The method as claimed in claim 8, wherein the gripper (222) of the primary gripper system includes any of an electrostatic gripper and a magnetic gripper.