Amphibious robotic crawler

• US 8,317,555 B2
• Filed: 06/11/2010
• Issued: 11/27/2012
• Est. Priority Date: 06/11/2009
• Status: Active Grant

• Current Assignee: SARCOS LC (Sarcos Technology & Robotics Corp.)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Jacobsen, Stephen C., Smith, Fraser M., Olivier, Marc X.
• Primary Examiner(s): AVILA, STEPHEN P
• Application Number:
  US12/814,302
• Publication Number:
  US 20100317244A1
• Time in Patent Office: 900 Days
• Field of Search: 440/12.63, 114/312
• US Class Current: 440/12.63
• CPC Class Codes: B63C 11/34 Diving chambers with mechanical link, e.g. cable, to a base manipulators B25J; externally attached cofferdams and the like B63B17/0018; diving chambers without mechanical link to a base B63G8/00; caissons adapted to laying foundations E02D23/00 - E02D27/00
• CPC Class Codes: B63C 11/52 Tools specially adapted for working underwater, not otherwise provided for

Abstract

An amphibious robotic crawler for traversing a body of water having two frame units coupled end-to-end or in tandem by an actuated linkage arm. Each frame unit includes a housing with a drivable continuous track rotatably supported thereon. The frame units are operable with a power supply, a drive mechanism and a control module. Each frame unit further includes a buoyancy control element for suspending the frame unit in the water, and for controlling the depth of the robotic crawler within the water. The control module coordinates the rotation of the continuous tracks, the position of the linkage arm and the buoyancy of the buoyancy control elements to control movement, direction and pose of the robotic crawler through the body of water.

Claims

1. A segmented robotic crawler for traversing about or through a body of water comprising:

at least two frame units including a housing containing a drive mechanism;

a drivable, continuous track operable with each frame unit and rotatably supported around the housing, the track further comprising a plurality of tread elements, wherein at least one surface of the continuous track is exposed to enable engagement with the body of water;

a control module for guiding the robotic crawler in the body of water;

at least one drive unit coupled between the continuous track and the drive mechanism;

at least one actuated linkage arm coupled between the frame units to provide controllable bending about at least two axes; and

at least one buoyancy control element disposed on the frame units adapted to control the buoyancy of the frame units in the body of water

wherein the plurality of tread elements further comprise a plurality of extendable and one of retractable and foldable type tread elements, and wherein the tread elements one of retract and fold during travel in a first directional motion for disengagement from the water and extend during travel in a second directional motion for engagement with the water.

2. The segmented robotic crawler of claim 1, wherein the buoyancy control element is an inflatable receptacle configured to expand in an outward direction from the frame units.

3. The segmented robotic crawler of claim 1, wherein the buoyancy control elements comprises a plurality of separate compartments which can be individually filled with a buoyant material to provide additional control over the pose and trim of the robotic crawler as it moves through the body of water.

4. The segmented robotic crawler of claim 1, wherein the buoyancy control elements are retractably supported about the frame units.

5. The segmented robotic crawler of claim 2, wherein the inflatable receptacle is filled with a buoyant material selected from the group consisting of foam, pressurized gas, a fuel gas derived from a phase change of a fuel source and a product gas derived from a chemical reaction between two or more reactants.

6. The segmented robotic crawler of claim 1, wherein the buoyancy of the buoyancy control element is controllable to cause the frame units to ascend within the body of water, wherein the buoyancy control elements comprise positive buoyancy control elements.

7. The segmented robotic crawler of claim 1, wherein the buoyancy of the buoyancy control element is controllable to cause the frame units to be suspended at a neutral depth below the surface of the body water.

8. The segmented robotic crawler of claim 1, wherein the buoyancy of the buoyancy control element is controllable to cause the frame units to descend within the body of water, the buoyancy control elements comprising negative buoyancy control elements.

9. The segmented robotic crawler of claim 1, wherein the buoyancy of the buoyancy control element is controllable to adjust an attitude of the frame units suspended in the body water.

10. The segmented robotic crawler of claim 1, wherein an upper portion of each continuous track is lifted above the surface of the water and a lower portion of each continuous track is configured to propel the crawler through the water as the plurality of tread elements move through the water.

11. The segmented robotic crawler of claim 1, wherein a portion of each continuous track is covered and an uncovered portion of each continuous track is configured to propel the crawler through the water as the plurality of tread elements move through and push against the water.

12. The segmented robotic crawler of claim 1, further comprising an asymmetric propulsion-enhancing tread that provides an asymmetric thrust between the opposing surfaces of the tracks to increase the mobility of the robotic crawler through the water.

13. The segmented robotic crawler of claim 1, further comprising means for manipulating the tread elements about the track.

14. The segmented robotic crawler of claim 13, wherein the means for manipulating comprises a mechanical manipulator selected from the group consisting of a guide mechanism that mechanically directs the tread elements depending upon position, a spring and latch mechanism that forces the tread elements closed and latched along a first direction of travel, and that releases the tread elements along a second, opposite direction of travel.

15. The segmented robotic crawler of claim 13, wherein the means for manipulating comprises an electrical manipulator that manipulates the tread elements in response to an electrical signal.

16. The segmented robotic crawler of claim 13, wherein the means for manipulating comprises a fluid manipulator, wherein the tread elements are manipulated in response to a fluid pressure.

17. The segmented robotic crawler of claim 1, wherein the at least one actuated linkage arm is adapted to provide relative rotation between the frame units about a roll axis.

18. The segmented robotic crawler of claim 1, wherein the actuated linkage arm further comprises a steering mechanism, wherein the frame units may be selectively oriented and positioned relative to one another to control steering of the robotic crawler within the water.

19. The segmented robotic crawler of claim 1, further comprising at least one controllable planar surface extending from the frame units to provide additional steering control of the crawler through the water.

20. The segmented robotic crawler of claim 1, wherein the control module further comprises electronic hardware and downloadable software.

21. The segmented robotic crawler of claim 1, further comprising at least one auxiliary propulsion module deployable from a frame unit and configured to propel the crawler through the water.

22. A self-powered amphibious robotic crawler comprising:

at least two frame units, each frame unit further comprising;

a housing containing a drive mechanism;

a continuous track supported therein having at least one surface with tread elements exposed for engagement with a body of water; and

a controllable drive unit coupled between the continuous track and the drive mechanism; and

at least one actuated linkage arm coupled between the frame units to provide controllable bending about at least two axes and including a steering mechanism;

at least one power supply providing power to the actuated linkage arm and the drive mechanisms of each frame unit;

at least one buoyancy control element disposed on the frame units; and

at least one control module operable with the frame units, the control module being configured to direct the robot through the body of water with controllable bending of the at least one linkage arm and controllable movement of the continuous tracks,

wherein the plurality of tread elements further comprise a plurality of extendable and one of retractable and foldable type tread elements, and wherein the tread elements one of retract and fold during travel in a first directional motion for disengagement from the water and extend during travel in a second directional motion for engagement with the water.

23. The robotic crawler of claim 22, wherein the buoyancy of the buoyancy control element is controllable by the control module.

24. The robotic crawler of claim 22, further comprising the at least one actuated linkage arm providing controllable relative rotation between the at least two frame units about a roll axis.

25. A method of operating a segmented robotic crawler through a body of water comprising:

providing two frame units coupled by an actuated linkage arm to form a segmented robotic crawler, each frame unit having a continuous track with tread elements coupled to a drive source to provide rotation of the continuous track there around, wherein the plurality of tread elements further comprise a plurality of extendable and one of retractable and foldable type tread elements;

suspending each frame unit in the water with at least one buoyancy control element;

selectively engaging at least one surface of each continuous track with the water during rotation of the track to propel the frame unit through the water, said selectively engaging comprising one of retracting and folding of the plurality of tread elements during travel in a first directional motion for disengagement from the water and facilitating extending of the tread elements during travel in a second directional motion for engagement with the water;

activating the actuated linkage arm to control an angular alignment between the two frame units, wherein controlling the angular alignment results in at least partially steering the crawler; and

coordinating rotation of each continuous track and actuation of the actuated linkage arm to direct the crawler along predetermined course through the body of water.

26. The method of claim 25, further comprising filling the buoyancy control element with a positive buoyant material to cause the robotic crawler to ascend or remain neutral within the body of water.

27. The method of claim 25, wherein the positive buoyant material is selected from the group consisting of foam, pressurized gas, a fuel gas derived from a phase change of a fuel source and a product gas derived from a chemical reaction between two or more reactants.

28. The method of claim 25, further comprising filling the buoyancy control element with a negative buoyant material to cause the robotic crawler to descend within the body of water.

29. The method of claim 25, further comprising adjusting the buoyancy of each buoyancy control element to control the depth of the crawler in the body of water.

30. The method of claim 25, further comprising selectively controlling the amount of buoyant material present within a plurality of compartments formed in the buoyancy control element to adjust the attitude of the robotic crawler while traveling through the body of water.

31. The method of claim 25, wherein suspending each frame unit in the water with the buoyancy control element further comprises extending an inflatable receptacle from a side of the frame unit.

32. The method of claim 31, wherein extending the inflatable receptacle further comprises filling the inflatable receptacle with a buoyant material selected from the group consisting of a positive buoyant material and a negative buoyant material.

33. The method of claim 31, further comprising inflating the inflatable receptacle when the crawler enters the body of water and deflating the inflatable receptacle when the crawler leaves the body of water.

34. The method of claim 25, wherein selectively engaging one surface of each continuous track with the water further comprises floating the frame unit at the surface of the body of water to lift an upper portion of the track above the surface to engage a lower portion of the track with the water.

35. The method of claim 25, wherein selectively engaging one surface of each continuous track with the water further comprises covering a portion of the track to engage an uncovered portion of the track with the water.

36. The method of claim 25, wherein activating the actuated linkage arm further comprises bending the linkage arm until the two frame units are orientated substantially side-by-side in a tank configuration.

37. The method of claim 25, further comprising activating a roll joint in the actuated linkage arm to provide relative rotation between the two frame units about a roll axis.

38. The method of claim 25, further comprising rotating the angle of at least one pivoting planar surface extending from each of the two frame units to provide additional steering of the crawler through the water.

39. The method of claim 25, further comprising detaching the buoyancy control element from the frame units when the crawler leaves the body of water.

40. A segmented robotic crawler for traversing about or through a body of water comprising:

at least two frame units including a housing containing a drive mechanism;

a drivable, continuous track operable with each frame unit and rotatably supported around the housing, the track further comprising a plurality of tread elements, wherein at least one surface of the continuous track is exposed to enable engagement with the body of water;

a control module for guiding the robotic crawler in the body of water;

at least one drive unit coupled between the continuous track and the drive mechanism;

at least one actuated linkage arm coupled between the frame units to provide controllable bending about at least two axes; and

a controllable planar surface extending from the frame units and adapted to operate with the continuous track to enable the crawler to maintain a desired depth in the body of water,

wherein the plurality of tread elements further comprise a plurality of extendable and one of retractable and foldable type tread elements, and wherein the tread elements one of retract and fold during travel in a first directional motion for disengagement from the water and extend during travel in a second directional motion for engagement with the water.