阅读说明：本技术 用于机器人臂的多级止动装置 (Multi-stage stop device for robot arm ) 是由 D·P·诺尔博伊 于 2020-03-11 设计创作，主要内容包括：本申请描述了用于机器人臂的多级止动装置。在第一级期间,机器人臂的连杆的旋转运动压缩多级止动装置的可压缩构件,以吸收和消解由碰撞产生的至少一些力。第二级提供硬止动,该硬止动停止任何进一步的旋转。本文中所述的多级止动装置可以包括伸缩销,该销配置成在第一级期间压缩可压缩构件。在销收缩后,在第二级期间刚性侧壁提供硬止动,从而防止进一步旋转。(The present application describes a multi-stage stopping device for a robotic arm. During the first stage, rotational movement of the links of the robotic arm compresses the compressible members of the multi-stage stops to absorb and counteract at least some of the forces generated by the collision. The second stage provides a hard stop that stops any further rotation. The multi-stage stop arrangement described herein may include a telescoping pin configured to compress the compressible member during the first stage. After the pin is retracted, the rigid sidewall provides a hard stop during the second stage, preventing further rotation.)

1. A multi-stage stopping device for a robotic arm, the multi-stage stopping device comprising:

a frame member configured to be mounted to one of a first link and a base of a robotic arm, wherein the first link and the base are connected by a rotational joint such that the first link rotates relative to the base, the frame member including a first sidewall defining a first opening therethrough;

a compressible member positioned within the frame member; and

a first pin including a first shaft extending from a first head to a first distal end, wherein the first shaft is slidably received within the first opening of the first sidewall and the first head is positioned between the first sidewall and the compressible member.

2. The multi-stage stop device of claim 1, wherein a first force acting on the first distal end of the first pin moves the first pin toward the compressible member, thereby compressing the compressible member to absorb the first force.

3. The multi-stage stop device of claim 2, wherein contact between the frame member and a protruding member on the one of the first link and the base stops rotation of the first link relative to the base.

4. The multi-stage retaining device of claim 1,

the frame member further includes a second sidewall defining a second opening therethrough; and is

The multi-stage stop further comprises a second pin comprising a second shaft extending from a second head to a second distal end, wherein the second shaft is slidably received within the second opening of the second sidewall and the second head is positioned between the second sidewall and the compressible member.

5. The multi-stage stop device according to claim 4, wherein a second force acting on the second distal end of the second pin moves the second pin toward the compressible member, thereby compressing the compressible member to absorb the second force.

6. The multi-stage stop device according to claim 1, wherein the compressible member comprises a rubber block having a shore hardness of at least 40A.

7. The multi-stage retaining device of claim 1,

the frame member includes a keyed profile configured to correspond with a keyed slot of the one of the first link and the base of the robotic arm, the frame member configured to mount to the one of the first link and the base, and

the frame member is at least partially received within the keyed slot when mounted to the one of the first link and the base of the robotic arm.

8. The multi-stage stop device of claim 1, further comprising a mechanical fastener extending through the frame member to mount the frame member to the one of the first link and the base of the robotic arm.

9. The multi-stage stop device according to claim 1, wherein the first head comprises a shape larger than the first opening.

10. A robotic system, the robotic system comprising:

a first link of a robotic arm connected to a base by a rotary joint such that the first link rotates relative to the base; and

a multi-stage detent device, the multi-stage detent device comprising:

a frame member mounted to one of the first link and the base, the frame member including a first sidewall defining a first opening therethrough;

a compressible member positioned within the frame member; and

a first pin comprising a first shaft extending from a first head to a first distal end, wherein the first shaft is slidably received within the first opening of the first sidewall and the first head is positioned between the first sidewall and the compressible member; and

a first protruding member mounted to the other of the first link and the base, the first protruding member positioned to contact the first distal end of the first pin at a first rotational position of the first link relative to the base to limit rotation of the first link in a first rotational direction.

11. The robotic system of claim 10, wherein the first protruding member comprises a bolt.

12. The robotic system of claim 10, wherein,

the frame member further includes a second sidewall defining a second opening therethrough; and is

The multi-stage stop further comprises a second pin comprising a second shaft extending from a second head to a second distal end, wherein the second shaft is slidably received within the second opening of the second sidewall and the second head is positioned between the second sidewall and the compressible member.

13. The robotic system of claim 12, wherein the first protruding member contacts the second distal end of the second pin at a second rotational position to limit rotation of the first link in a second rotational direction.

14. The robotic system of claim 12, further comprising a second protruding member mounted to the other of the first link and the base, the second protruding member positioned to contact the second distal end of the second pin at a second rotational position of the first link relative to the base to limit rotation of the base in a second rotational direction.

15. The robotic system of claim 14, wherein the second protruding member comprises a bolt.

16. The robotic system of claim 14, wherein the positions of the first and second protruding members are adjustable.

17. The robotic system of claim 10, wherein,

the one of the first link and the base includes a key slot;

the frame member includes a keyed profile configured to correspond with the keyed slot; and is

The frame member is at least partially received within the keyed slot.

18. The robotic system of claim 10, further comprising a mechanical fastener extending through a mounting opening of the frame member and to the one of the first link and the base to mount the frame member to the one of the first link and the base.

19. The robotic system of claim 10, wherein the frame member is mounted to an interior portion of a housing of the one of the first link and the base.

20. The robotic system of claim 10, wherein the frame member is mounted to the first link.

21. The robotic system of claim 10, wherein the compressible member comprises a rubber block having a shore hardness of at least 40A.

Technical Field

The present application relates to robotic systems, and more particularly to multi-stage stopping devices, systems, and methods for mechanically limiting and/or stopping the rotation of a robotic arm or other component.

Background

Robotic arms are available to perform a variety of tasks and are particularly common in automation. A robotic arm typically includes a plurality of links connected by one or more joints. The one or more joints are driven by various types of actuators (e.g., electric motors, hydraulics, etc.) to control joints of the robotic arm to position an end effector configured to perform a task. In some cases, the robotic arm may include a physical stop (e.g., a hard stop) that may be configured to limit rotational movement between the links of the arm. Such a stop device may limit damage to the robot arm or injury to others in the event of a failure of the robot arm.

Disclosure of Invention

The present application describes multi-stage stopping devices (and related systems and methods) configured for use with robotic arms and other robotic systems. The multi-stage stop device may be configured to provide a mechanical mechanism to limit rotation at a rotary joint of a robotic arm to which the multi-stage stop device is mounted. In some embodiments, the multi-stage stopping device may be used as a mechanical safety mechanism to stop or limit the rotation of the robotic arm in the event of a failure.

The multi-stage stopping devices described herein are referred to as "multi-stage" because they comprise two stages for stopping rotational movement, as will be described below. During the first stage, the rotational motion compresses the compressible member to absorb and counteract at least a portion of the force generated by the impact. The second stage provides a hard stop that stops any further rotation. The multi-stage stop arrangement described herein may include a telescoping pin configured to compress the compressible member during the first stage. After pin retraction, the rigid sidewalls of the multi-stage stop arrangement provide a hard stop during the second stage, preventing further rotation.

As a first embodiment, a multi-stage stopping device for a robot arm may include: a frame member configured to be mounted to one of a first link and a base of a robotic arm. The first link and the base are connected by a rotary joint such that the first link rotates relative to the base. The frame member includes a first sidewall defining a first opening therethrough. The multi-stage stop arrangement includes a compressible member positioned within the frame member. The multi-stage stop device also includes a first pin including a first shaft extending from the first head to the first distal end. The first shaft is slidably received within the first opening of the first sidewall, and the first head is positioned between the first sidewall and the compressible member.

In some embodiments, the multi-stage stop device may include one or more of the following features in any combination: (a) wherein a first force acting on the first distal end of the first pin moves the first pin toward the compressible member, thereby compressing the compressible member to absorb the first force; (b) wherein contact between the frame member and a protruding member on the one of the first link and the base stops rotation of the first link relative to the base; (c) wherein the frame member further comprises a second sidewall defining a second opening therethrough; and the multi-stage stop further comprises a second pin comprising a second shaft extending from a second head to a second distal end, wherein the second shaft is slidably received within the second opening of the second sidewall and the second head is positioned between the second sidewall and the compressible member; (d) wherein a second force acting on the second distal end of the second pin moves the second pin toward the compressible member, thereby compressing the compressible member to absorb the second force; (e) wherein the compressible member comprises a rubber block having a shore hardness of at least 40A; (f) wherein the frame member includes a keyed profile configured to correspond with a keyed slot of the one of the first link and the base of the robotic arm, the frame member configured to be mounted to the one of the first link and the base and at least partially received within the keyed slot when mounted to the one of the first link and the base of the robotic arm; (g) a mechanical fastener extends through the frame member to mount the frame member to the one of the first link and the base of the robotic arm; (h) wherein the frame member is configured to be mounted to a first link of a robotic arm; (i) wherein the first head comprises a shape larger than the first opening; and/or any additional features described in the detailed description section below.

As another embodiment, a robotic system may comprise: a first link of a robot arm connected to a base of the robot arm by means of a rotary joint such that the first link rotates relative to the base. The robotic system also includes a multi-stage stopping device. The multi-stage stopping device comprises: a frame member mounted to one of the first link and the base, the frame member including a first sidewall defining a first opening therethrough; a compressible member positioned within the frame member; and a first pin including a first shaft extending from a first head to a first distal end, wherein the first shaft is slidably received within the first opening of the first sidewall and the first head is positioned between the first sidewall and the compressible member. The robotic system also includes a first protruding member mounted to the other of the first link and the base. The first protruding member is positioned to contact the first distal end of the first pin at a first rotational position of the first link relative to the base to limit rotation of the first link in a first rotational direction.

In some embodiments, the robotic system may include one or more of the following features in any combination: (a) wherein the first protruding member comprises a bolt; (b) wherein the frame member further comprises a second sidewall defining a second opening therethrough; and the multi-stage stop further comprises a second pin comprising a second shaft extending from a second head to a second distal end, wherein the second shaft is slidably received within the second opening of the second sidewall and the second head is positioned between the second sidewall and the compressible member; (c) wherein the first protruding member contacts the second distal end of the second pin at a second rotational position to limit rotation of the first link in a second rotational direction; (d) a second projecting member mounted to the other of the first link and the base, the second projecting member positioned to contact the second distal end of the second pin at a second rotational position of the first link relative to the base to limit rotation of the base in a second rotational direction; (e) wherein the second protruding member comprises a bolt; (f) wherein the position of the first protruding member and the second protruding member is adjustable; (g) wherein the one of the first link and the base includes a key slot; the frame member includes a keyed profile configured to correspond with the keyed slot; and the frame member is at least partially received within the keying slot; (h) a mechanical fastener extends through a mounting opening of the frame member and to the one of the first link and the base to mount the frame member to the one of the first link and the base; (i) wherein the frame member is mounted to an interior portion of the housing of the one of the first link and the base; (j) wherein the frame member is mounted to the first link; (k) wherein the compressible member comprises a rubber block having a shore hardness of at least 40A; and/or any additional features described in the detailed description section below.

Drawings

The features and advantages of the multi-stage retaining device, system, and method described herein will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. These drawings depict only several embodiments in accordance with the disclosure and are not to be considered limiting of its scope. In the drawings, like reference numbers or symbols generally indicate like parts, unless the context dictates otherwise. The drawings may not be to scale.

FIG. 1 is an isometric view of one embodiment of a robotic arm.

FIG. 2A is a top perspective view of one embodiment of a multi-stage stopping device that may be configured for use with, for example, the robotic arm of FIG. 1.

Fig. 2B is a bottom perspective view of the multi-stage stop device of fig. 2A.

Fig. 2C is a top view of the multi-stage retaining device of fig. 2A.

Fig. 3 is a perspective view illustrating a portion of one embodiment of a first link of the robotic arm of fig. 1 including a keyed slot configured to receive the multi-stage stop of fig. 2A.

Fig. 4 is a perspective view illustrating the multi-stage stopper of fig. 2A mounted in the key groove of fig. 3.

FIG. 5 is a perspective view showing a portion of a base of the robotic arm of FIG. 1, the base including a protruding member configured to contact the multi-stage stop to limit rotation of the first link of the robotic arm.

Fig. 6A is a cross-sectional view of the robotic arm of fig. 1, the cross-sectional view being taken through a rotational joint between the base and the first link to illustrate the multi-stage stop and the projecting member.

Fig. 6B is another cross-sectional view of the robotic arm of fig. 1, taken through the rotational joint between the base and the first link in an embodiment including a multi-stage stop and two projecting members.

Fig. 7A-7C illustrate the function of the multi-stage retaining device of fig. 2A according to one embodiment.

FIG. 7A illustrates one embodiment of the multi-stage stop prior to contact with the protruding member.

Fig. 7B illustrates one embodiment of the multi-stage retaining device during contact with the protruding member. In this embodiment, the protruding member contacts the distal end of the pin of the multi-stage stop arrangement causing the pin to compress the compressible member of the multi-stage stop arrangement.

Fig. 7C illustrates one embodiment of the multi-stage retaining device during contact with the protruding member. In this embodiment, the protruding member is in contact with the side wall of the multi-stage stop arrangement.

Detailed Description

Features of the multi-stage retaining device, system, and method of the present disclosure will now be described in detail with reference to certain embodiments shown in the drawings. The illustrated embodiments described herein are provided by way of illustration and are not intended to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the present subject matter. It will be readily understood that the aspects and features of the present disclosure, as described below and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which form a part of this disclosure, by one of ordinary skill in the art.

FIG. 1 is an isometric view of one embodiment of a robotic arm 10, which robotic arm 10 may include a multi-stage stopping device 100 as described herein. In the embodiment shown, the multi-stage stop device 100 is not visible in fig. 1. The multi-stage stop device 100 is shown, for example, in fig. 2A-2C, which will be described further below. As shown in fig. 1, in the illustrated embodiment, the robotic arm 10 includes a base 12, a first link 14, a second link 16, and an end effector 18. The multi-stage stopping device 100 described further below may also be used on other types of robotic arms or systems. The illustrated robotic arm 10 is provided by way of example only.

Base 12 may be configured to support other portions of robotic arm 10. In some embodiments, base 12 houses many of the electronic components of robotic arm 10. The first link 14 may be connected to the base 12 by a first rotational joint 20. The first rotational joint 20 allows the first link 14 to rotate relative to the base 12. In the illustrated embodiment, the first link 14 rotates relative to the base 12 about a first axis of rotation 24. In general, rotation of the first link 14 relative to the base 12 may be controlled by execution of one or more sequences of instructions (i.e., software) and/or with the aid of custom hardware (e.g., an application specific integrated circuit, a field programmable gate array, etc.). However, it may be beneficial or desirable to provide a mechanical mechanism to limit or stop the rotation of the first link 14 relative to the base 12, for example, in the event of a failure of the robotic arm 10. The multi-stage stop device 100 described in the present application may be included at the first rotary joint 20 to provide this function. For example, a multi-stage stop device 100 may be included at the first rotational joint 20 to limit or stop rotation of the first link 14 relative to the base 12.

With continued reference to fig. 1, the second link 16 is connected to the first link 14 by a second rotational joint 22. The second rotational joint 22 allows the second link 16 to rotate relative to the first link 14. In the illustrated embodiment, the second link 16 rotates relative to the first link 14 about a second axis of rotation 26. Also, in general, the rotation of the second link 16 relative to the first link 14 may be controlled or limited by software or custom hardware. However, in the event of a failure of the robotic arm 10, it may be beneficial or desirable to provide a mechanical mechanism to limit or stop the rotation of the second link 16 relative to the first link 14. In some embodiments, a multi-step stop device 100 described below may be included at the second rotary joint 22 to provide this function. For example, a multi-stage stop device 100 may be included at the second rotational joint 22 to limit or stop rotation of the second link 16 relative to the first link 14. In some embodiments, different types of stop devices may be included at the second rotational joint 22.

In the illustrated embodiment, the base 12, the first link 14, and the second link 16 are arranged to form a Selective Compliance Assembly Robotic Arm (SCARA). The multi-stage retaining device 100 can be used at any one of the swivel joints of the SCARA. The multi-stage stopping device 100 may also be configured for use with other types of robotic arms (e.g., non-SCARA robotic arms).

In the embodiment shown in fig. 1, robotic arm 10 includes an end effector 18. In this embodiment, the end effector 18 may be positioned by rotating the first and/or second links 14, 16 about the first and/or second axes of rotation 24, 26. End effector 18 may be configured to perform a variety of tasks, as will be apparent to those of ordinary skill in the art.

In many of the embodiments described below, the multi-stage stop device 100 is described with reference to the first rotational joint 20 between the first link 14 and the base 12. This is done for ease of description and it is to be understood that the multi-stage stop device 100 may alternatively or additionally be used at any other rotational joint of the robotic arm 10.

Fig. 2A-2C illustrate one embodiment of a multi-stage retaining device 100 according to the present disclosure. Fig. 2A is a top perspective view of multi-stage retaining device 100, fig. 2B is a bottom perspective view of multi-stage retaining device 100, and fig. 2C is a top view of multi-stage retaining device 100.

As described above, the multi-stage stopping device 100 may be configured to stop or limit rotation at a rotational joint of a robotic arm or system (e.g., the robotic arm 10 shown in fig. 1 or other robotic arms or systems). For example, referring to the robotic arm 10 of fig. 1, a multi-stage stop device 100 may be mounted at the first rotary joint 20 to stop or limit rotation of the first link 14 relative to the base 12, and/or a multi-stage stop device 100 may be mounted at the second rotary joint 22 to stop or limit rotation of the second link 16 relative to the first link 14. An installation embodiment of the multi-stage stopping device 100 will be described in more detail below with reference to fig. 3 to 5.

In the embodiment shown in fig. 2A-2C, the multi-stage stop device 100 includes a frame member 102, a first pin 104, a second pin 106, and a compressible member 108. These features will now be described in more detail.

The frame member 102 may comprise the body or housing of the multi-stage retaining device 100. In the illustrated embodiment, the frame member 102 comprises a single, unitary piece. In some embodiments, the frame member 102 may include more than one piece joined together to form the frame member 102. The frame member 102 may be made of a strong, rigid material, such as many types of metals. In some embodiments, the frame member 102 is made of steel.

As shown in fig. 2A, in the illustrated embodiment, the frame member 102 includes a first sidewall 110. The first sidewall 110 may include a first opening 112 defined therein. That is, the first opening 112 may be formed through the first sidewall 110 and extend through the first sidewall 110. As shown, in some embodiments, the first opening 112 extends along a first pin axis 132. The first opening 112 may be configured to receive the first pin 104 therethrough. For example, as shown, the first pin 104 extends through the first opening 112 and through the first sidewall 110 of the frame member 102. The first opening 112 may be configured such that the first pin 104 is slidably received within the first opening 112. To this end, in some embodiments, the first opening 112 may be slightly larger (e.g., about 1%, 2.5%, 5%, 10%, 15%, or 20% larger in cross-sectional area, diameter, etc.) than the first pin 104, allowing the first pin 104 to slide back and forth through the first opening 112 along the first pin axis 132. In the illustrated embodiment, the first opening 112 is shown as having a circular cross-section, which corresponds to the circular cross-section of the first pin 104. Generally, although not always, the cross-section of the first opening 112 is configured to correspond to the cross-section of the first pin 104. Further, in some embodiments, the cross-section of the first opening 112 and the first pin 104 may include other non-circular shapes.

Likewise, in the illustrated embodiment, the frame member 102 also includes a second sidewall 114. The second sidewall 114 may be positioned on the frame member 102 on a side of the frame member 102 opposite the first sidewall 110. In the illustrated embodiment, the second sidewall 114 includes a second opening 116 defined therein. That is, the second opening 116 may be formed through the second sidewall 114 and extend through the second sidewall 114. As shown, in some embodiments, the second opening 116 extends along a second pin axis 140. The second opening 116 may be configured to receive the second pin 106 therethrough. For example, as shown, the second pin 106 extends through the second opening 116 and through the second sidewall 114 of the frame member 102. The second opening 116 may be configured such that the second pin 106 is slidably received within the second opening 116. For example, the second opening 116 may be slightly larger (e.g., 1%, 2.5%, 5%, 10%, 15%, or 20% larger) than the second pin 106, thereby allowing the second pin 106 to slide back and forth along the second pin axis 140 through the second opening 116. In some embodiments, the second opening 116 is the same size as the first opening 112, although this need not be the case in all embodiments. In the illustrated embodiment, the second opening 116 is shown as having a circular cross-section, which corresponds to the circular cross-section of the second pin 106. Generally, although not always, the cross-section of the second opening 116 is configured to correspond to the cross-section of the second pin 106. Further, in some embodiments, the cross-section of the second opening 116 and the second pin 106 may include other non-circular shapes.

As shown in fig. 2A, the frame member 102 may also include an outer sidewall 118. In the illustrated embodiment, outer sidewall 118 extends between first sidewall 110 and second sidewall 114 at the top of frame member 102 (relative to the orientation shown in the figures). Further, the frame member 102 may also include an inner portion 120. As shown, in some embodiments, the interior portion 120 extends between the first sidewall 110 and the second sidewall 114 at the bottom of the frame member 102 (relative to the orientation shown in the figures).

Accordingly, the frame member 102 may include a first sidewall 110, a second sidewall 114, an outer sidewall 118, and an interior portion 120, such as shown in fig. 2A. The first sidewall 110, the second sidewall 114, the outer sidewall 118, and the inner portion 120 may be arranged to define a space 122 therebetween. For example, as shown in fig. 2A, the space 122 is defined and bounded on a first side by the first sidewall 110, on a second side by the second sidewall 114, on a third side by the outer sidewall 118, and on a fourth side by the interior portion 120. As will be described in greater detail below, the compressible member 108 may be received and positioned within the space 122. That is, as shown, the compressible member 108 may be positioned between the first sidewall 110, the second sidewall 114, the outer sidewall 118, and the inner portion 120.

The first side wall 110, the second side wall 114, the outer side wall 118, and the inner side portion 120 may be arranged such that the frame member 102 includes a keyed profile 124. The term "contour" when used in reference to the frame member 102 refers to an outer contour or outer shape of the frame member 102 when viewed from above (e.g., as shown in fig. 2C) or below. For example, in the illustrated embodiment, the profile of the frame member 102 includes a generally four-sided, wedge-like shape with rounded corners. Certain features of this shape will be described in more detail below with reference to fig. 2C. Furthermore, the profiles shown are provided by way of example only, and other profile shapes for the frame member 102 are possible. The profile of the frame member 102 is referred to as "keyed" because, as will be described below with reference to fig. 3 and 4, it may be configured to fit within a corresponding keyed slot 158 when mounted to the robotic arm 10.

With continued reference to fig. 2A, features present in some embodiments of the first and second pins 104, 106 will now be described. In the illustrated embodiment, the first pin 104 includes a first shaft 126. As shown, the first shaft 126 includes a circular cross-section, although this is not true in all embodiments, and other cross-sectional shapes of the first shaft 126 are possible. The first shaft 126 extends along a first pin axis 132 between the first head 128 and the first distal end 130. As shown in fig. 2A, the first shaft 126 of the first pin 104 extends through the first opening 112 of the first sidewall 110. As described above, the first shaft 126 may be slidably received within the first opening 112 such that the first pin 104 may slide back and forth through the first opening 112 along the first pin axis 132. To facilitate sliding, in some embodiments, the first shaft 126 may be slightly smaller (e.g., about 1%, 2.5%, 5%, 10%, 15%, or 20% smaller) than the first opening 112.

As shown in fig. 2A, the first head 128 of the first pin 104 may be positioned between the first sidewall 110 and the compressible member 108. In some embodiments, for example, as shown, the first head 128 may include a shape or diameter that is larger than the first opening 112. This aspect may be included to retain the first pin 104 within the first opening 112. For example, as shown, the first head 128 prevents the first pin 104 from sliding completely out of the first opening 112. Thus, from the position shown in fig. 2A, the first pin 104 may slide inward toward the compressible member 108 (causing the compressible member 108 to be compressed), but is restricted or prevented from sliding outward (away from the compressible member) because the first head 128 does not fit through the first opening 112.

As shown in fig. 2A, the enlarged first head 128 may also advantageously distribute forces over a larger surface area of the compressible member 108. As will be described in more detail below with reference to fig. 7A-7C, a force may be applied to the distal end 130 of the first pin 104 during use of the multi-stage stop 100. The force may cause the first pin 104 to slide along the first pin axis 132 toward the compressible member 108 (causing compression of the compressible member 108). The first head 128 may contact the compressible member 108 and transfer forces acting on the first pin 104 to the compressible member 108. The enlarged first head 128 may distribute the force over a greater portion of the compressible member 108.

In many respects, the second pin 106 may be similar to the first pin 104. For example, in the illustrated embodiment, the second pin 106 includes a second shaft 134. The second shaft 134 may include a circular cross-section, although this is not true in all embodiments, and other cross-sectional shapes of the second shaft 134 are possible. The second shaft 134 extends along a second pin axis 140 between the second head 136 and the second distal end 138. As shown in fig. 2A, the second shaft 134 of the second pin 106 extends through the second opening 116 of the second sidewall 114. As described above, the second shaft 134 may be slidably received within the second opening 116 such that the second pin 106 may slide back and forth through the second opening 116 along the second pin axis 140. To facilitate sliding, in some embodiments, the second shaft 134 may be slightly smaller (e.g., about 1%, 2.5%, 5%, 10%, 15%, or 20% smaller) than the second opening 116.

As shown in fig. 2A, the second head 136 of the second pin 106 may be positioned between the second sidewall 114 and the compressible member 108. In some embodiments, for example, as shown, the second head 136 may include a shape or diameter that is larger than the second opening 116. This aspect may be included to retain the second pin 106 within the second opening 116. As shown, the second head 134 prevents the second pin 106 from sliding completely out of the second opening 116. Thus, from the position shown in fig. 2A, the second pin 106 may slide inward toward the compressible member 108 (causing the compressible member 108 to be compressed), but is restricted or prevented from sliding outward (away from the compressible member) because the second head 136 does not fit through the second opening 116. Similar to the first pin 104, the enlarged second head 136 on the second pin 106 may also advantageously distribute forces over a larger surface area of the compressible member 108, as shown in fig. 2A.

The first pin 104 and the second pin 106 may be made of a strong, rigid material, such as many types of metals. In some embodiments, the first pin 104 and the second pin 106 are made of steel. In some embodiments, the first pin 104 and the second pin 106 are cast. In some embodiments, the first pin 104 and the second pin 106 are identical.

As shown in fig. 2A, in some embodiments, the compressible member 108 is positioned within the space 122 between the first head 128 of the first pin 104 and the second head 136 of the second pin 106. More specifically, in some embodiments, the first head 128 of the first pin 104 acts on the first wall 142 of the compressible member 108 and the second head 136 of the second pin 106 acts on the second wall 144 of the compressible member 108. Thus, in some embodiments, a force acting on the first distal end 130 of the first pin 104 or the second distal end 138 of the second pin 106 may be transferred to the compressible member 108 via the first pin 104 or the second pin 106. If the force is sufficient, it may cause the compressible member 108 to compress, which may advantageously absorb the force. As mentioned above, this may provide a first stage of the multi-stage retaining device 100. For example, in the event of a collision, some of the force may be absorbed by compression of the compressible member 108, as explained in further detail below with reference to fig. 7A-7C.

The illustrated embodiment includes a first pin 104 and a second pin 106 on opposite sides of a compressible member 108, which may be advantageously used to limit rotational movement in both rotational directions. Further, this design may be advantageous because it may be configured to use a single compressible member 108 that functions with both the first pin 104 and the second pin 106. Such a configuration may advantageously reduce the size of the multi-stage retaining device 100, allowing it to be installed in small spaces. Although the illustrated embodiment includes a first pin 104 and a second pin 106, in some embodiments, only a single pin may be included. A single pin arrangement may be used to limit rotation in only a single direction.

In the illustrated embodiment, the compressible member 108 includes a hexagonal shape. This is not true in all embodiments, and other shapes of the compressible member 108 are possible.

As shown in the embodiment shown in fig. 2A, the compressible member 108 may comprise a block of material. The material may be selected to have a stiffness configured to absorb forces expected during an impact. The expected force during the collision may be determined based on considerations of various parameters of the robotic arm including, for example, the size and weight of the robotic arm and its various linkages, the rotational speed of the robotic arm, the potential payload of the robotic arm operation, and the placement of the multi-stage stopping device 100.

For example, a larger, heavier robotic arm working with a heavier payload may generate greater forces during a collision than a smaller, lighter robotic arm working with a lighter payload. As another example, a robotic arm operating at a higher speed may generate a greater force during a collision than a robotic arm operating at a slower speed. As another example, a multi-stage stop device 100 placed closer to the axis of rotation may experience greater forces during a collision than a multi-stage stop device 100 placed further from the axis of rotation.

In some embodiments, the compressible member 108 may include a harder material when higher forces are expected. In some embodiments, the material of the compressible member 108 may have a shore hardness of at least about 40A, 50A, 60A, 70A, 80A, 90A, 100A, 10D, 20D, 30D, 40D, 50D, 60D, 70D, 75D, 80D, 90D, or 100D. In some embodiments, the compressible member 108 may comprise a rubber material. In some embodiments, the compressible member 108 may comprise a spring.

In some embodiments, for example, as shown in fig. 2A, the multi-stage stopping device 100 may include a mounting hole 146, the mounting hole 146 configured to receive a fastener 148 for attaching the multi-stage stopping device 100 to the robotic arm 10. In the illustrated embodiment, the mounting holes 146 are formed through the inner portion 120 of the frame member 102. In the illustrated embodiment, the fasteners 148 include bolts (as shown). Other mechanisms for securing multi-stage stopping device 100 to robotic arm 10 are possible. Fig. 4, described below, illustrates one embodiment of the multi-stage stop 100 in an installed position.

Fig. 2B is a bottom perspective view of multi-stage stop device 100. As shown in fig. 2B, in some embodiments, the frame member 102 further includes a bottom wall 150 (i.e., a bottom wall, according to its configuration installed in the robotic device of fig. 1). The bottom wall 150 may extend between the first sidewall 110, the second sidewall 114, the outer sidewall 118, and the inner portion 120. The bottom wall 150 may partially define a space 122 in which the compressible member 108 is positioned. In some embodiments, as shown, the bottom wall 150 includes an aperture 152 formed therein.

Fig. 2C is a top view of multi-stage retaining device 100 and shows: in some embodiments, some aspects of the profile 124 of the frame member 102 may be determined based in part on the placement of the multi-stage stop device 100 relative to the axis of rotation 154 of the rotary joint in which the multi-stage stop device 100 is installed. As shown in fig. 2C, the first sidewall 110 and the second sidewall 114 may form an angle α with respect to each other. As shown, the angle α may cause the frame member 102 to have a wedge shape. The angle α may be configured such that the planes of the first sidewall 110 and the second sidewall 114 intersect at the axis of rotation 154. Such an angle α may provide that the first pin axis 132 and the second pin axis 140 are tangent to a circle 156 formed at a radius R from the axis of rotation. The first pin 104 and the second pin 106 may be positioned at a radius R from the circle 156. The angle β formed between the first wall 142 and the second wall 144 of the compressible member 108 may be substantially equal to or about equal to the angle α. This may provide that the force induced on the compressible member 108 by the first pin 104 or the second pin 106 acts in a direction orthogonal to the first wall 142 or the second wall 144. In some embodiments, such a configuration may facilitate installation of the multi-stage stopping device 100 inside the robotic arm 10.

Fig. 3 is a perspective view illustrating one embodiment of a keyed slot 158 configured to receive the multi-stage stop 100 of fig. 2A-2C. In the illustrated embodiment, the keying slot 158 is formed on the first link 14 of the robotic arm 10 of fig. 1. In particular, in the illustrated embodiment, the keyed slot 158 is formed on an interior portion or surface 166 of a housing 168 of the first link 14. The interior portion or surface 166 of the housing 168 may be a portion of the first link 14 that is not visible when the robotic arm 10 is assembled. In some embodiments, an interior portion or surface 166 of the housing 168 may face an interior surface or portion 170 of the base 12 when the robotic arm 10 is assembled (see, e.g., fig. 5). However, in some embodiments, the keying slot 158 may be positioned on an exterior portion or surface of the housing 168. In addition, the keying slots 158 may also be formed at different locations, as will be described further below. For example, in some embodiments, the keying slot 158 may be formed on an interior surface or an exterior surface of the base 12. In some embodiments, the multi-stage stopping device 100 may be positioned at a joint between two links of a robotic arm. Thus, in some embodiments, the key slot 158 may be positioned on either link.

As shown in fig. 3, the keyed slot 158 is configured to correspond in shape and size to the keyed profile 124 of the frame member 102 of the multi-stage stop 100. The keyed slot 158 may be configured to closely receive the multi-stage stop device 100 such that the play (e.g., relative movement, clearance, etc.) between the multi-stage stop device 100 and the keyed slot 158 is limited when the multi-stage stop device 100 is positioned within the keyed slot 158.

As shown, the keying slot 158 may include a mounting hole 160. The mounting hole 160 can be configured to receive a portion of the fastener 148 of the multi-stage stop 100 to secure the multi-stage stop 100 in the keyed slot 158. For example, the fastener 148 may extend through the mounting hole 146 of the frame member 102 of the multi-stage retaining device 100 and into the mounting hole 160 of the keyed slot 158. In some embodiments, the fastener 148 includes a bolt, and the mounting hole 160 is threaded to receive a threaded end of the bolt.

In some embodiments, as shown, the key slot 158 further includes a protrusion 162. The projection 162 may be configured to extend partially into the space 122 of the multi-stage retaining device 100 to hold the compressible member 108 in place. For example, in the illustrated embodiment, the projection 162 includes a V-shape configured to extend into the space 122 between the first and second sidewalls 110, 114 of the frame member 102 and contact a surface of the compressible member 108. Although the protrusion 162 is shown as having a V-shape, in other embodiments, the protrusion 162 may include other shapes.

As described above, the keyed slot 158 is configured to at least partially receive the multi-stage stop 100 therein. This may serve one or more beneficial purposes. For example, the keying slot 158 may be used to ensure that the multi-stage retaining device 100 is properly oriented and positioned when installed. In some embodiments, the engagement between the keyed slot 158 and the keyed profile 124 of the multi-stage stop 100 may ensure or help ensure that the multi-stage stop 100 can only be installed in a single position in a single orientation. This may prevent or reduce the likelihood of the multi-stage stop device 100 being installed incorrectly and position the multi-stage stop device 100 correctly with respect to the axis of rotation 24 (see also fig. 2C, which shows the relative position between the multi-stage stop device 100 and the axis of rotation 154).

As another example, the engagement between the keyed slot 158 and the keyed profile 124 of the multi-stage stop device 100 may advantageously transmit force between the multi-stage stop device 100 and a portion of the robotic arm 10 (e.g., the first link 14 in the illustrated embodiment) to which the multi-stage stop device 100 is attached. For example, during a collision, forces acting on the multi-step stop 100 may be transferred between the multi-step stop 100 and the first link 14 through contact between the multi-step stop 100 and the wall 164 of the key slot 158. This may advantageously distribute forces that may shear fastener 148 if fastener 148 is the only mechanism securing multi-stage retaining device 100 to first link 14. Thus, in some embodiments, a system incorporating multi-stage retaining device 100 and keyed slot 158 may be able to handle greater forces than a system that does not include keyed slot 158. However, in some embodiments where the force is low, the multi-stage stop device 100 may be used without the keying slot 158.

Fig. 4 is a perspective view showing the multi-stage stop device 100 installed in the key slot 158 of fig. 3. As shown, the frame member 102 is closely received within the keyed slot 158 due to the corresponding nature of the keyed profiles 124 and the keyed slot 158. As described above, this may advantageously ensure that the multi-stage stop device 100 is properly oriented and positioned and that forces are transmitted between the multi-stage stop device 100 and the first link 14. Further, as shown, the fastener 148 may secure the multi-stage retaining device 100 into the keyed slot 158. The fasteners 148 may include, for example, mechanical fasteners (e.g., bolts).

In the illustrated embodiment, when installed, the multi-stage stop device 100 is positioned on an interior surface or portion 166 of the housing 168 of the first link 14. The positioning of the multi-stage stop device 100 on the interior surface or portion 166 of the housing 168 may be advantageous because it may hide the multi-stage stop device 100, thereby improving the appearance of the robotic arm 10. In other embodiments, the multi-step stop 100 may be positioned on an exterior surface or portion of the housing 168 of the first link 14, or on an interior or exterior surface or portion of the base 12.

Fig. 5 is a perspective view illustrating a portion of the base 12 of the robotic arm 10 of fig. 1, the base 12 including a protruding member 172, the protruding member 172 configured to contact the multi-stage stop device 100 to limit or stop rotation of the first link 14 relative to the base 12 about the rotational axis 24. In the illustrated embodiment, the protruding member 172 protrudes from an interior portion or surface 170 of the housing 174 of the base 12. The interior portion or surface 170 of the housing 174 may be a portion of the base 12 that is not visible when the robotic arm 10 is assembled. In some embodiments, the interior portion or inner surface 170 of the housing 174 may face the interior surface or inner portion 166 of the first link 14 when the robotic arm 10 is assembled (see, e.g., fig. 4 and 5).

The protruding member 172 is positioned to contact the first pin 104 and/or the second pin 106 of the multi-stage stop 100 when the first link 14 is rotated relative to the base 12. Thus, if the multi-stage stop device 100 is positioned on an interior portion or surface of the first link 14, the protruding member 172 may be positioned on a corresponding interior portion or surface of the base 12 (or vice versa). Likewise, if the multi-stage stop device 100 is positioned on an exterior portion or surface of the first link 14, the protruding member 172 may be positioned on a corresponding exterior portion or surface of the base 12 (or vice versa). In some embodiments, the multi-stage retaining device 100 can be positioned on an interior portion or surface of the first link 14 and the protruding member 172 can be positioned on a corresponding exterior portion or surface of the base 12 (or vice versa).

The protruding member 172 may be positioned at the same distance from the rotational axis 24 as the first and second pins 104, 106, such that the protruding member 172 contacts the first and/or second pins 104, 106 during rotation of the first link 14 relative to the base 12. As will be described in greater detail with reference to fig. 7A-7C, contact between the protruding member 172 and the first pin 104 and/or the second pin 106 limits or stops rotation of the first link 14 relative to the base 12.

In some embodiments, for example, as shown, the protruding member 172 may comprise a bolt. In the illustrated embodiment, the bolt head protrudes from an interior surface or portion 170 of the base 12 to a position to contact the first pin 104 and/or the second pin 106 during rotation of the first link 14 relative to the base 12. As shown in fig. 5, in some embodiments, the interior surface or portion 170 of the base 12 may include a plurality of locations 176 where the protruding members 172 may be mounted. For example, in fig. 5, the interior surface or portion 170 of the base 12 includes eight locations 176 where the protruding members 172 may be mounted. In the embodiment shown, eight locations 176 include eight bolt holes into which bolts may be fitted. In some embodiments, other numbers of locations 176 (e.g., one, two, three, four, five, six, etc.) may be included. The different positions 176 allow the protruding member 172 to be mounted in different positions such that the protruding member 172 contacts the first pin 104 and/or the second pin 106 at different rotational positions during rotation of the first link 14 relative to the base 12. Further, in some embodiments, more than one protruding member 172 may be mounted so as to limit the range of rotational motion between the first link 14 and the base 12, as shown in fig. 6B described below.

Fig. 6A is a cross-sectional view of the robotic arm 10 of fig. 1, taken through the rotary joint 20 (see fig. 1) between the base 12 and the first link 14 to illustrate the multi-stage stop 100 and the projecting member 172 according to the first embodiment. The illustrated embodiment includes a single protruding member 172 (as shown). Thus, the first link 14 may rotate relative to the base 12 about the axis of rotation 24 through the illustrated range of rotation 178. At the end of the range of rotation 178 (shown with an arrow on the dashed line), the first and second pins 104, 106 contact the protruding member 172 to limit and stop rotation.

Fig. 6B is another cross-sectional view of robotic arm 10 of fig. 1, taken through rotary joint 20 between base 12 and first link 14 in an embodiment including multi-stage stop 100 and two projecting members 172. In this embodiment, since the first link 14 can only rotate relative to the base 12 within the rotation range 178 between the two protruding members 172, the rotation range 178 is reduced.

As will be apparent to those of ordinary skill in the art in view of fig. 6A and 6B (and the general disclosure), the range of rotation 178 of the first link 14 relative to the base 12 can be adjusted by adjusting the position and number of the protruding members 172 (e.g., using one or two). As described above, the protruding member 172 may be mounted in any possible location 176.

At each end of the range of rotation 178, one of the first pin 104 and the second pin 106 is in contact with the protruding member 172. Fig. 7A to 7C illustrate the function of the multi-stage stopping device 100 when the multi-stage stopping device 100 is in contact with the protruding member 172. Fig. 7A to 7C illustrate the contact between the first pin 104 and the protruding member 172. The contact between the second pin 106 and the protruding member 172 may be similar.

Fig. 7A shows the multi-stage stop device 100 prior to contact with the protruding member 172. The multi-stage stop device 100 is in a default configuration prior to contact and the compressible member 108 is in an uncompressed state. When the first link 14 rotates relative to the base 12, the protruding member 172 approaches the first pin 104 in the direction indicated by the arrow.

Fig. 7B illustrates one embodiment of a "first stage" of the multi-stage retaining device 100 during contact with the protruding member 172. In this embodiment, when the protruding member 172 contacts the distal end of the first pin 104 of the multi-stage stop device 100, the first pin 104 is driven inward, thereby compressing the compressible member 108 of the multi-stage stop device 100. In some embodiments, compression of the compressible member 108 absorbs and counteracts the impact forces between the protruding members 172 and the multi-stage retaining device 100. The first stage of the multi-stage stopping device 100 may be a compliant stage that occurs as the first pin 104 compresses the compressible member 108.

Fig. 7C illustrates one embodiment of a "second stage" of the multi-stage retaining device 100 during contact with the protruding member 172. In this embodiment, the protruding member 172 has fully driven the first pin 104 such that the protruding member 172 is now in contact with the first sidewall 110 of the multi-stage stop device 100. The first sidewall 110 acts as a hard stop preventing further rotation of the first link 14 relative to the base 12. The second stage of the multi-stage stop device 100 may be a hard stop stage that occurs when the protruding member comes into contact with the first sidewall 110 of the multi-stage stop device 100, preventing any further rotation.

The multi-stage detent device 100 described herein may provide advantages not achievable with other types of mechanical detent devices. Other mechanical stops typically include only a hard stop that abruptly stops rotation. These other hard stops are typically formed by bolt-to-bolt or bolt-to-rubber direct contact, which can cause significant wear on the robotic arms on which they are mounted. Furthermore, these other hard stops are typically located outside of the robotic arm, which may be disadvantageous. Finally, these other hard stops are typically positioned at predetermined locations such that the user cannot adjust the angle of rotation of the arm.

In contrast, the multi-stage stop device 100 described herein may advantageously include a first compliant stage and a second hard stop stage, which may reduce wear on the robotic arm. Further, the multi-stage stop device 100 may be positioned within the interior of the robotic arm (as in the embodiments described above). Finally, the multi-step retaining device 100 may be adjustable by moving the protruding member 172 to any available position 176 (see fig. 5, 6A, and 6B).

The multi-stage stop arrangement shown in fig. 2A has been tested on the robotic arm 10 shown in fig. 1 and successfully stopped rotating about the axis 24 while withstanding full speed and full payload collisions. The shore hardness of the compressible member 108 tested was 75D. However, this is only one example, and as mentioned above, many other implementations are possible.

The foregoing description details certain embodiments of the systems, devices, and methods disclosed herein. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the systems, apparatus, and methods may be practiced in many ways. Furthermore, as noted above, it should be noted that the use of particular terminology when describing certain features or aspects of the disclosure should not be taken to imply that the terminology is being redefined herein to be restricted to including any specific characteristics of the technical features or aspects with which that terminology is associated.

It will be understood by those skilled in the art that various modifications and changes may be made without departing from the scope of the described technology. Such modifications and variations are intended to fall within the scope of the present embodiments. Those skilled in the art will also appreciate that components included in one embodiment may be interchanged with components from other embodiments; one or more components from the depicted embodiments may be included in any combination in other depicted embodiments. For example, any of the various components described herein and/or depicted in the figures may be combined with, interchanged with, or excluded from the other embodiments.

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. For clarity, various singular/plural permutations may be expressly set forth herein.

Directional terminology (e.g., top, bottom, side, upward, downward, inward, outward, etc.) used herein is used generally with reference to the orientation shown in the drawings and is not intended to be limiting. For example, the top surface described above may refer to a bottom surface or a side surface. Thus, features described as being on the top surface may be included on the bottom surface, the side surfaces, or any other surface.

It will be understood by those within the art that, in general, terms used herein are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" should typically be interpreted to mean "at least one" and "one or more"); the same holds true for the use of definite articles used to introduce claims. Furthermore, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "a or B" will be understood to include the possibility of "a" or "B" or "a and B".

As used herein, the term "consisting of … …" is synonymous with "including," "comprising," or "characterized by," and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps.

The above description discloses several methods and materials of the present invention. The present invention is capable of modifications in the methods and materials, as well as variations in the methods and apparatus of manufacture. Such variations would become clear to one of ordinary skill in the art upon consideration of this disclosure or practice of the invention disclosed herein. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed herein, but that the invention will include all modifications and alternatives falling within the true scope and spirit of the invention as embodied in the following claims.