Tool attachment, tool changer and corresponding method of use

Abstract

A tool attachment (200) for a robotic manipulator (100), includes a housing (202), an input shaft (208) configured to be engaged by an end effector (105) of the robotic manipulator (100), an output shaft (210), and a tool (214) coupled to the output shaft (210). The housing (202) includes at least one slot or at least one projection for preventing relative rotational movement between the housing (202) and a housing of the robotic manipulator (100). Upon engagement of the end effector (105) of the robotic manipulator (100) with the input shaft (208), the tool attachment (200) is retained on the robotic manipulator (100), and rotational movement of the end effector (105) of the robotic manipulator (100) acts to rotate said input shaft (208) and drive said tool (214).

Claims

1. A tool attachment for a robotic manipulator, comprising: a housing configured to engage with the robotic manipulator; an input shaft configured to be engaged by an end effector of the robotic manipulator; an output shaft coupled to the input shaft; and a tool coupled to said output shaft, wherein: said housing comprises means for preventing relative rotational movement between said housing and a housing of the robotic manipulator; upon engagement of the end effector of the robotic manipulator with the input shaft, the tool attachment is retained on the robotic manipulator, and rotational movement of the end effector of the robotic manipulator acts to rotate said input shaft relative to said housing and drive said tool; wherein said housing of the tool attachment comprises a hollow sleeve portion having a first, open, end and a second, closed, end, said tool disposed at said second end, said input shaft being within an interior space of said hollow sleeve portion; and wherein said hollow sleeve portion is shaped to form a guide portion at said first, open, end, the guide portion being configured to radially align, relative to a longitudinal axis of said housing of the tool attachment, and guide the robotic manipulator into the interior space of said hollow sleeve portion of said housing of the tool attachment.

2. The tool attachment for the robotic manipulator according to claim 1, wherein said guide portion is frusto-conical.

3. The tool attachment for the robotic manipulator according to claim 1, wherein a rotational axis of said input shaft is substantially aligned with the longitudinal axis of said housing of the tool attachment.

4. The tool attachment for the robotic manipulator according to claim 1, wherein said means for preventing relative rotational movement comprises at least one slot, the slot configured to engage with a corresponding projection on the robotic manipulator or each slot configured to engage with a respective projection on the robotic manipulator.

5. The tool attachment for the robotic manipulator according to claim 1, wherein said input shaft comprises an interface portion configured to be engaged by the end effector of the robotic manipulator.

6. The tool attachment for the robotic manipulator according to claim 5, wherein said interface portion comprises a bar affixed perpendicular to said input shaft to form a T-piece.

7. The tool attachment for the robotic manipulator according to claim 1, wherein the tool is a rotary tool, and wherein the output shaft is coupled to the input shaft by a transmission unit comprising an input coupled to the input shaft and an output coupled to the output shaft, said transmission unit configured such that the rotational speed of the output is higher than the rotational speed of the input, or such that the rotational speed of the output is lower than the rotational speed of the input.

8. The tool attachment for the robotic manipulator according to claim 7, wherein a rotational axis of the transmission unit output is angularly offset from a rotational axis of the transmission unit input.

9. The tool attachment for the robotic manipulator according to claim 7, wherein said rotary tool is a cutting disc.

10. The tool attachment for the robotic manipulator according to claim 1, wherein the tool is a linear tool, and wherein the output shaft is coupled to the input shaft by a linear transmission unit comprising an input coupled to the input shaft and an output coupled to the output shaft, said transmission unit configured such that rotation input shaft causes linear movement of the output shaft.

11. The tool attachment for the robotic manipulator according to claim 10, wherein said linear tool is one of: a cable cutter; a gripper comprising three or more jaws; an orange peel grabber; and a sample collector.

12. A tool changer comprising: a plurality of the tool attachments according to claim 1; and a tooling basket comprising a plurality of mounts, each mount configured to releasably mount a respective one of the plurality of tool attachments.

13. The tool changer according to claim 12, wherein said tooling basket is configured to be mounted to an unmanned underwater vehicle.

14. The tool changer according to claim 12, wherein said tooling basket comprises a rotatably mounted carousel configured to selectively rotate said plurality of tool attachments to a position in which one of the tool attachments can be engaged by the robotic manipulator.

15. A method of use of a tool changer comprising a plurality of the tool attachments according to claim 1, the method comprising the steps of: engaging the input shaft of a first tool attachment of the plurality of tool attachments with an end effector of the robotic manipulator; dismounting the first tool attachment from a first mount of the tool changer; and remounting the first tool attachment onto the first mount of the tool changer.

16. The method according to claim 15, further comprising the step of: performing an action with the first tool attachment.

17. The method according to claim 15, further comprising the step of: engaging the input shaft of a second tool attachment of the plurality of tool attachments with the end effector of the robotic manipulator; and dismounting the second tool attachment from a second mount of the tool changer.

18. The method according to claim 15, further comprising the step of: rotating, selectively, a carousel of the tool changer, to position a specific one of the plurality of tool attachments so as to be engageable by the end effector of the robotic manipulator.

19. The tool attachment for the robotic manipulator according to claim 1, wherein said means for preventing relative rotational movement comprises at least one projection, the projection configured to engage with a corresponding slot on the robotic manipulator or each projection configured to engage with a respective slot on the robotic manipulator.

Description

BRIEF DESCRIPTIONS OF THE DRAWINGS

(1) The invention will now be further described with reference to the figures in which:

(2) FIG. 1 is a side view of an exemplary robotic manipulator;

(3) FIG. 2 is a schematic cross-section of a tool attachment according to the present invention;

(4) FIG. 3A is a cut-away perspective view of the tool attachment of FIG. 2 without part of its housing, and the exemplary end effector of FIG. 1 connected to a robotic manipulator;

(5) FIG. 3B is a close-up perspective view of a connection between the housing of the tool attachment of FIG. 2 and the exemplary end effector of FIG. 1;

(6) FIG. 4 is a perspective view of an exemplary unmanned underwater vehicle and a tool changer according to the present invention;

(7) FIG. 5 shows an enlarged perspective view of the tool changer of FIG. 4 and a portion of the exemplary unmanned underwater vehicle;

(8) FIGS. 6a and 6b show further examples of tools suitable for the tool attachment; and

(9) FIG. 7 shows a flow diagram of the operation of selecting a tool from a carousel.

(10) FIG. 8 schematically depicts an alternative arrangement for the means for preventing relative rotation between the housing of the tool attachment and the housing of the robotic manipulator.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(11) FIG. 1 is a side view a distal end of an exemplary robotic manipulator 100, which comprises a housing 102, and which comprises plurality of connectors 104, such as wires, configured to be connected to the remaining portions of the robotic manipulator (not shown).

(12) The terms distal and proximal are used herein to describe the relative positions of components of the robotic manipulator 100 and the tool attachment 200. An exemplary robotic manipulator 100, or a tool attachment 200 according to the present invention, has a proximal end which is closest to a robotic manipulator and a distal end which is furthest from a robotic manipulator.

(13) The robotic manipulator 100 terminates distally in an end effector 105. The end effector 105 is a gripper module 106 having two prongs or fingers 108. The gripper module 106 is configured to allow each of the prongs or fingers 108 to be actuated to close a gap 110 between the prongs or fingers 108 to grip, or engage, objects external to the robotic manipulator 100. The gripper module 106 is also configured to rotate, powered by a drive motor, about a longitudinal axis of the robotic manipulator.

(14) As shown in FIGS. 2, 3A, and 3B, a tool attachment 200 according to the present invention comprises a housing 202 having a proximal end 201A which is open, shown at the top of FIG. 2, and a distal end 201B which is closed, shown at the bottom of FIG. 2. The proximal end 201A of the housing 202 comprises a guide portion 203, which is frusto-conical. The housing 202 is a hollow sleeve which defines a cavity 204 configured to receive a robotic manipulator 100 and a portion of a robotic manipulator.

(15) As the distal portion of the robotic manipulator 100 comprising the gripper module 106 enters the cavity 204 to engage the tool attachment 200, the guide portion 203 is configured to guide the distal portion of the robotic manipulator 100 into the cavity 204 as well as radially aligning the robotic manipulator 100 with the housing 202.

(16) At its proximal end 201A, the housing 202 further comprises a plurality of slots 206 configured to engage with corresponding projections on a housing 102 of the robotic manipulator 100. As such, the slots-and-projections prevent relative rotational between the housing 202 of the tool attachment 200 and the housing 102 of the robotic manipulator 100. That is to say, the slots and projections transfer the torque generated when the end effector, i.e. the gripper module 106, rotates to power the tool 214.

(17) Only some of the slots 206 are shown in FIGS. 2, 3A, and 3B. In some embodiments, there are three slots, or four slots, and the slots are spaced evenly around the circumference of the housing, such that the torque that must be resisted by the slots-and-projections to prevent the relative rotational motion of the housings 102, 202 to one another can be evenly distributed around the circumference.

(18) The gripper module 106 is configured to engage an input shaft 208 of the tool attachment 200. The gripper module 106 is attached to the robotic manipulator 100.

(19) The housing 102 of the robotic manipulator 100 comprises a plurality of projections 302 which correspond to the plurality of slots 206 in the housing 202 of the tool attachment 200.

(20) The input shaft 208 is coupled to an output shaft 210. When the input shaft 208 is engaged by the gripper module 106 of the robotic manipulator 100, rotational movement of the gripper module 106 acts to rotate the input shaft 208, and said rotation of the input shaft 208 drives the output shaft 210.

(21) The input shaft 208 is substantially co-axial with the longitudinal axis of the housing 202, such that the rotational axis of the input shaft 208 is aligned with the longitudinal axis of the housing 202, so that there is substantially no angular moment between the robotic manipulator 100 and the input shaft 208.

(22) Proximally, the input shaft 208 comprises an interface portion, configured to be engaged by the robotic manipulator 100, which is a bar 212 affixed perpendicular to said input shaft 208. The input shaft 208 and the bar 212 form a T-piece which facilitates engagement of the input shaft 208 by the robotic manipulator 100.

(23) At the distal end 201B, the tool attachment 200 comprises the tool 214. In the embodiment shown in FIG. 2, the tool 214 is a rotary brush. As the tool 214 is a rotary tool, the output shaft 210 is coupled to the input shaft 208 by a transmission unit 216 or gear box. The transmission unit 216 allows for the rotational speed of the output shaft 210 to be different to that of the input shaft 208in this example the transmission unit is an epicyclic, planetary, gearbox comprising a ring gear 218 fixed to the housing 220 of the transmission unit 216, a series of planet gears 222a, 222b, . . . , fixed to a planet carrier 224, and a sun gear 226. In this example, the planet carrier 224 is coupled to the input shaft 208, and the sun gear 226 is coupled to the output shaft 210, and so the rotational speed of the output shaft will be greater than the rotational speed of the input shaft. As will be appreciated, if it is required that the rotational speed of the output shaft is less than the rotational speed of the input shaft then the transmission unit may be arranged such that the input shaft is coupled to the sun gear and the output shaft is coupled to the planer carrier.

(24) As shown in the cut-away perspective view of the tool attachment 200 in FIG. 3A, the gripper module 106 is configured to enter the cavity 204 defined by housing 202 to engage the input shaft 208 via the bar 212.

(25) FIGS. 4 and 5 show a UUV 400 comprising two robotic manipulators 100, each robotic manipulator 100 comprising a gripper module 106 as end effector 105. The robotic manipulators 100 comprise joints 402 and linkages 404.

(26) Also shown is a tool changer 500 according to the present invention. The tool changer 500 comprises a plurality of tool attachments 200. Each tool attachment 200 comprises a different tool 214A, 214B, 214C.

(27) The tool changer 500 is defined by a tooling basket 502 comprising a plurality of mounts 504A, 504B, 504C. Each mount 504A, 504B, 504C is configured to receive one of the tool attachments 200.

(28) Each tool attachment 200 is releasably mounted on a respective one of the mounts 504A, 504B, 504C. Although not shown, the tooling basket 502 may be mounted to the UUV 400 by a fastening means, such as bolts or wires. Alternatively, the tooling basket 502 may be mounted to the UUV 400 by quick release pins. The quick release pins may be remotely actuatable to enable the UUV to dock and undock with the tooling basket while subsea. In this alternative, the tooling basket 502 may remain, for example, on the seafloor while the UUV carries out the mission.

(29) A first tool attachment 200A is mounted on a first mount 504A, and comprises a rotary tool such as the rotary brush 214A also shown in FIGS. 2 and 2A. Although the rotational speed of the rotary brush 214A may differ from a rotational speed of the robotic manipulator 100 due to the transmission unit 216, the rotational axis of the rotary brush 214A is coaxial to the rotational axis of the robotic manipulator 100.

(30) A second tool attachment 200B is mounted on a second mount 504B, and comprises a linear tool such as a cable cutter 214B. The second tool attachment 200B therefore comprises a linear transmission unit which is configured to convert rotational movement of the input shaft 208 into linear movement of the output shaft 210.

(31) The conversion of rotary motion to linear motion may be achieved by any means known to the skilled person, such as a screw type mechanism, rack and pinion mechanisms, slider-crank mechanisms, or the like. The screw type mechanism may be a lead screw, ball screw or satellite roller screw, mechanism.

(32) A third tool attachment 200C is mounted on a third mount 504C, and comprises a rotary tool such as a cutting disc or grinding disc 214C, the rotational motion of which is angularly offset from a rotational axis of the input shaft 208. The angular transmission unit 506 of the third tool attachment 200C allows for rotational movement of the input shaft 208 to be angularly offset, such that rotational motion of the output shaft 210 occurs along a different rotational axis than rotational motion of the input shaft 208. The rotational axis of the cutting disc or grinding disc 214C is offset by about 90 degrees from the rotational axis of the input shaft 208.

(33) Although the tool changer 500 is shown as having three tools 214A, 214B, 214C attached to three tool attachments 200A, 200B, 200B mounted on three mounts 504A, 504B, 504C, the tool changer 500 may comprise any number of tools. Tools with further functionality may be easily envisaged by the skilled person.

(34) Any variety of linear tools may be envisaged be the skilled person, and although the cable cutter 214B is configured to move linearly in a direction of the rotational axis of the input shaft 208, the linear tool may move in a direction which is angularly offset from the rotational axis of the input shaft 208.

(35) Similarly, any variety of angular tools may be envisaged, and rotational movement of such an angular tool may be along the rotational axis of the input shaft 208, or it may be angularly offset from the rotational axis of the input shaft 208. Additionally or alternatively, the rotational speed of the output shaft 210 may be different to the rotational speed of the input shaft 208, and the rotational speed of the output shaft 210 may be variable dependently or independently of the speed of the input shaft 208.

(36) FIGS. 6(a) and 6(b) respectively show two examples of further linear actuated tools. In each example, the housing of the tool attachment device and the input to the transmission unit is that same as for the example shown and described with reference to FIG. 2. Looking first to FIG. 6(a), the tool attachment device 600 comprises a subsea sample collector tool 602. The tool comprises a pair of matching scoops, in the form of concave cups, configured to open and close upon linear actuation of the tool. The transmission unit 604 is configured to convert the rotational input to linear motion of the output shaft 606 which in turn acts on the lever arms of the tool 602.

(37) Looking now to FIG. 6(b), the tool attachment device 608 comprises an orange peel grabber tool 610. The orange peel grabber tool 610 comprises a plurality of concave sections which, upon the grabber being closed, form an enclosed space in which material may be held. Similarly to the tool attachment 600, the tool attachment 608 further comprises transmission unit 612 which is configured to convert the rotational input to linear motion of the output shaft 614 which in turn acts on the lever arms of the tool 610.

(38) As the reach of the robotic manipulators 100 attached to the UUV 400 may be limited, the tooling basket 502 of the tool changer 500 may comprise a carousel which is rotatable such that a selected one of the three tool attachments 200A, 200B, 200C is in a position to be engaged by the gripper module 106 of the robotic manipulator 100.

(39) FIG. 7 shows a method of use of a tool changer 500 of the present invention. The end effector 105 of the robotic manipulator 100 engages 702 an input shaft 210 of a first tool attachment 200A. The robotic manipulator 100 then dismounts 704 the first tool attachment 200A from a first mount 504A of a tooling basket 502 of a tool changer 500.

(40) A tool 214A of the first tool attachment 200A may, optionally, be used to perform 706 an action. The first tool attachment 200A is then remounted 708 onto the first mount 504A of the tool changer 500.

(41) Optionally, a carousel of the tool changer 500 is rotated 710 to position a second tool attachment 200B to be engageable by the end effector 105 of the robotic manipulator 100.

(42) Further optionally, the end effector 105 of the robotic manipulator 100 engages 712 an input shaft of a second tool attachment 200B. A tool 214B of the second tool attachment 200B may then be used to perform an action.