Patent Description:
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).

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.

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.

<CIT> 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). <CIT> 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.

In accordance with another embodiment, the invention provides an end effector system according to appended claim <NUM>. 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.

In accordance with a further embodiment, the invention provides a method according to appended claim <NUM> 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.

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.

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.

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.

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.

<FIG> shows a robotic system <NUM> that includes an articulated arm <NUM> on a base <NUM>, and an end effector system <NUM>. As further shown in <FIG>, the end effector system may attach to the articulated arm <NUM> by way of an engagement feature <NUM> (such as threads, spring-loaded clasp, or ball and socket engagement) that mate with an engagement feature on the articulated arm <NUM>, and further, the end effector system may include a primary gripper system including a gripper on the end of an extender <NUM>, as well as secondary retention system <NUM> 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..

<FIG> diagrammatically show sectional views of an end effector system <NUM> that includes a primary gripper system including a gripper <NUM> on the end of an extender <NUM>. The end effector system <NUM> also includes a secondary retention system including a flexible toroid <NUM>.

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.

As shown in <FIG>, a portion of the outer surface of the flexible toroid <NUM> is attached to the inner surface of the housing <NUM> as shown at <NUM>, and a portion of the inner surface of the elastic toroid is attached to the extender at <NUM>. The toroid is able to move up and down (by rolling) between the outer collar and the inner extender.

With reference to <FIG>, the extender <NUM> may be moved in the direction as indicated at A such that the vacuum gripper <NUM> engages an object to be grasped <NUM>. By supplying a vacuum source through the extender <NUM>, the object may be engaged. As further shown in <FIG>, when the extender <NUM> 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 <NUM> undergoes this process of everting, it remains attached to the housing <NUM> at the attachment <NUM>.

As shown in <FIG>, 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 <NUM> 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 <NUM> is discharged). The elastic toroid is formed of a flexible material that may conform to the shape of the object <NUM> 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.

As shown in <FIG> (which show diagrammatic sectional views), an end effector system <NUM> includes a primary gripper system including a gripper <NUM> on the end of an extender <NUM>. The end effector system <NUM> also includes a secondary retention system including a jamming gripper <NUM> having one or more vacuum attachment ports <NUM>. 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 <NUM>, the jamming gripper <NUM> reduces its volume and grabs any object within its outer edge. The jamming gripper <NUM> is also attached to the interior of the housing <NUM> as shown at <NUM>.

As shown in <FIG>, the extender <NUM> may be extended, permitting the gripper <NUM> to engage an object <NUM>, and as shown in <FIG>, when the object is drawn up near or into the jamming gripper <NUM>, the jamming gripper engages at least a portion of the outer surface of the object <NUM>. As shown in <FIG>, when the vacuum source is applied to the jamming gripper <NUM>, the gripper <NUM> conforms to the surface of the object <NUM>, thereby securing the object <NUM> for transport or other processing operations.

In each of the embodiments of <FIG>, 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.

As shown in <FIG> (which show diagrammatic sectional views), an end effector system <NUM> includes a primary gripper system including a gripper <NUM> on the end of an extender <NUM>. The gripper <NUM> may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc. The end effector system <NUM> also includes a secondary retention system including a large area gripper <NUM> (e.g., a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc.) that surrounds the extender <NUM>. As shown in <FIG>, when the gripper <NUM> is extended into a cluttered environment (including, e.g., objects <NUM>, <NUM>, <NUM>), the gripper <NUM> may engage an object <NUM>, and draw the object toward the large area gripper <NUM>, which then surrounds the gripper <NUM>. The large area gripper <NUM> is then employed during rapid transport or further processing operations.

<FIG> show a diagrammatic sectional view of an end effector system <NUM>, which includes a primary gripper system including a gripper <NUM> on the end of an extender <NUM>. The gripper <NUM> may be any of a vacuum gripper, an electrostatic gripper, or a magnetic gripper etc. The end effector system <NUM> also includes a secondary retention system including two or more constricting actuators <NUM> (e.g., pinch grippers), that may be rotated with respect to pivot locations <NUM> such that a portion of each actuator <NUM> may engage a portion of an object to thereby secure the object.

In particular, as shown in <FIG>, the actuator <NUM> may be extended to engage an object such as a bag <NUM> that includes loose items <NUM>. As shown in <FIG>, the bag <NUM> may be acquired by the gripper <NUM>, and the constricting actuators <NUM> may then be rotated to secure the bag <NUM> within the end effector system <NUM>.

<FIG> show an end effector <NUM> that includes a first portion <NUM> having a vacuum cup that may be actuated to engage an object <NUM>, and then may withdraw the grasped object within a second portion <NUM> in the form of a shroud. In various embodiments, the first portion <NUM> may move toward the object while the shroud <NUM> remains fixed, or in other embodiments, the first portion may be fixed, and the shroud <NUM> may be actuated to move toward the object <NUM> once grasped.

<FIG> show an end effector <NUM> that includes a first portion <NUM> having a vacuum cup that may be actuated to engage an object <NUM>, and then may withdraw the grasped object <NUM>. A second portion <NUM> that includes two or more paddles <NUM> then move radially inward as shown at A to secure the grasped object <NUM>.

<FIG> show an end effector <NUM> that includes a first portion <NUM> having a vacuum cup that may be actuated to engage an object <NUM>. The object <NUM> is then withdrawn toward a second portion <NUM> that includes one or more additional vacuum cups <NUM> (three are shown) to secure the object <NUM> during transport. In accordance with further embodiments, the first portion <NUM> may be fixed with respect to an articulated arm, and the second portion <NUM> may be lowered onto the object <NUM>.

<FIG> show an end effector <NUM> that includes a first portion <NUM> having a vacuum cup that may be actuated to engage an object <NUM>. The object <NUM> is then withdrawn toward a second portion <NUM> that includes one or more compliant pads <NUM> to secure the object <NUM> during transport. In accordance with further embodiments, the first portion <NUM> may be fixed with respect to an articulated arm, and the second portion <NUM> may be lowered onto the object <NUM>.

<FIG> shows a robotic system <NUM> in accordance with an embodiment of the invention that includes an articulated arm <NUM> on a base <NUM>, and an end effector system <NUM>. The end effector system may include a primary gripper system including a gripper <NUM> on the end of an extender <NUM>, as well as secondary retention system <NUM> as discussed in more detail below with reference to <FIG>. 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..

<FIG> diagrammatically show views of the end effector system <NUM> in accordance with an embodiment of the present invention that includes a primary gripper system including the gripper <NUM> on the end of the extender <NUM>. The secondary retention system <NUM> includes a suspended cup <NUM> that may be mounted on an actuated member <NUM> such that the suspension point of the cup <NUM> may be moved relative to the base of the end effector system <NUM>.

As shown in <FIG>, the gripper <NUM> may engage and acquire an object <NUM>, and bring the object <NUM> toward the suspended cup <NUM>. As shown in <FIG>, the end effector <NUM> may then be rotated, causing the suspended cup to move below the object <NUM>. As shown in <FIG>, the object <NUM> may then be dropped into the suspended cup <NUM>. 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 <NUM> may include a releasable bottom <NUM> that may be actuated to drop the one or more objects into the output destination.

<FIG> shows a system <NUM> that includes an articulated arm <NUM> on a base <NUM> as well as an end effector portion <NUM>. The end effector portion <NUM> includes a primary acquisition portion <NUM> and a secondary retention system <NUM>. As further shown in <FIG>, the primary acquisition system includes a vacuum cup on an actuator shaft <NUM> that passes through an actuatable magnetic coil within arm <NUM>. The secondary retention system <NUM> includes a tray for supporting the object <NUM> once grasped as shown in <FIG>. As shown in <FIG>, such an end effector portion <NUM> may also be employed to selectively pull one object (e.g., <NUM>) from a mix of objects <NUM>. As shown in <FIG>, the primary acquisition system <NUM> may acquire the object <NUM>, and the secondary retention system may then support the retained object <NUM>.

As shown in <FIG>, a system <NUM> may provide an end effector system that includes a primary acquisition system <NUM> and a secondary retention system <NUM>, each of which includes a vacuum cup and a pivot joint. When the primary acquisition system <NUM> engages an object <NUM> (as shown in <FIG>), the end effector then rotates (as shown in <FIG>) such that the secondary retention system <NUM> also grasp the object <NUM> so that it may then be lifted and moved (as shown in <FIG>).

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. <FIG> show an example of a primary retention system <NUM> (that may be used with any of the above discussed embodiments), and includes a conduit <NUM> for selectively providing air at positive pressure to an end effector <NUM>. The conduit (which is provided within a second retention system <NUM> as discussed above), includes an area of restricted diameter <NUM> as well as a Venturi opening <NUM>. When positive air pressure is provided (as shown in <FIG>), the air blows out the end of the conduit and produces a vacuum source at the opening <NUM>, thereby permitting the end effector <NUM> to acquire an object <NUM>. Again, such a positive air pressure and Venturi system for providing the vacuum, may be used with each of the above embodiments.

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