Omnidirectional vehicle

• US 5,186,270 A
• Filed: 10/24/1991
• Issued: 02/16/1993
• Est. Priority Date: 10/24/1991
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: West, A. Mark T.
• Primary Examiner(s): Focarino, Margaret A.
• Assistant Examiner(s): Hurley, Kevin
• Application Number:
  US07/783,640
• Time in Patent Office: 481 Days
• Field of Search: 180/6.2, 180/6.44, 180/6.5, 180/6.6, 180/6.62, 180/6.7, 180/7.1, 180/7.2, 180/9.3, 180/9.34, 180/9.38, 180/9.44, 180/20, 180/199, 180/200, 180/202, 280/28.5, 901/1, 305/16, 305/17, 305/18, 305/15, 305/52
• US Class Current: 180/6.62
• CPC Class Codes: B25J 5/005 mounted on endless tracks or belts
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60L 2220/46 Wheel motors, i.e. motor connected to only one wheel
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2260/28 Four wheel or all wheel drive
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B62D 11/00 Steering non-deflectable wheels; Steering endless tracks or the like
• CPC Class Codes: B62D 55/08 Endless track units; Parts thereof
• CPC Class Codes: B62D 55/28 detachable
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

The invention provides controlled omnidirectional relative movement between a device and a selected surface in contact therewith. The device is preferably a vehicle having a first and second track mounted thereto, which tracks are parallel and spaced from each other and are independently driven in a first direction. A plurality of spheres are mounted in each of the tracks at intervals spaced in the first direction and the spheres in at least one of the tracks are driven to rotate in a second direction, generally perpendicular to the first direction. By suitably controlling the movements of the tracks in the first direction and of the spheres in the second direction, movement along any desired trajectory may be achieved with three degrees of freedom. By having the device stationary and the surface movable, an omnidirectional platform is provided.

Claims

1. An omnidirectional vehicle comprising:

a) a first track mounted to said vehicle;

b) a second track mounted to said vehicle parallel to and spaced from said first track;

c) first means for independently driving said first track and said second track in a first direction;

d) a plurality of spheres mounted in each of said tracks at intervals spaced in said first direction;

e) second means for driving the spheres in at least one of said tracks to rotate in a second direction generally perpendicular to said first direction; and

means for controlling said first and second means to move the vehicle in a desired direction.

2. A vehicle as claimed in claim 1 wherein said first means includes separate first and second motors, each of said motors having a rotating output shaft, and means for connecting the output shaft of the first motor to drive the first track and the output shaft of the second motor to drive the second track.

3. A vehicle as claimed in claim 1 wherein said second means includes at least one third motor having a rotating output shaft, and means for connecting the output shaft of the third motor to drive the spheres on at least one of said tracks.

4. A vehicle as claimed in claim 3 wherein said third motor drives the spheres in one of said tracks, and including a fourth motor for driving the spheres in the other track.

5. A vehicle as claimed in claim 3 wherein a selected plurality of the spheres in each track are in contact with a surface on which the vehicle is to move at any given time, the spheres in contact with the surface in each track changing as the tracks are driven;

and wherein the connecting means for the third motor includes a roller means in friction contact with at least selected ones of the spheres of a given track in contact with the surface at each time, and means for connecting the third motor output shaft to rotate said roller in said second direction.

6. A vehicle as claimed in claim 5 wherein there is a roller for each of said tracks in friction contact with the spheres thereof, and wherein the third motor output shaft is connected to rotate the rollers for both tracks.

7. A vehicle as claimed in claim 5 wherein there are two rollers for each track, both of which are in friction contact with at least selected ones of the spheres, the third motor output shaft being connected to rotate at least one of the rollers for at least one of the tracks.

8. A vehicle as claimed in claim 5 including a second plurality of spheres mounted in each of said tracks at spaced intervals in said first direction, the second plurality of spheres in each track being spaced in said second direction from the plurality of spheres in such track, and wherein the roller means for a given track is in friction contact with selected spheres from both plurality of spheres for the track.

9. A vehicle as claimed in claim 3 wherein said motors are electric motors, and wherein said means for controlling controls the drive current applied to each of said motors.

10. A vehicle as claimed in claim 1 wherein the vehicle moves on a selected surface, wherein said means for controlling includes means for indicating the desired direction of movement with reference to a selected prospective parallel to said surface, and means responsive to said indicating means for controlling the first and second driving means.

11. A vehicle as claimed in claim 10 wherein said means for indicating includes means for indicating a desired rotation of said vehicle about an axis perpendicular to said surface and means responsive to the indications of desired rotations for selectively operating at least said first means to rotate said vehicle about said axis.

12. A vehicle as claimed in claim 11 wherein said means for indicating is a joystick controller, said controller having a rotational input to indicate a desired rotation.

13. A vehicle as in claim 10 wherein said perspective is from within the vehicle, the first direction being the direction which the vehicle is facing.

14. A vehicle as claimed in claim 10 wherein said perspective is from outside the vehicle, the first direction being a selected direction on a surface on which to vehicle is moving.

15. A vehicle as claimed in claim 1 wherein said tracks are inside the vehicle, only said spheres projecting from the vehicle.

16. A vehicle as claimed in claim 15 wherein each track includes at least one low friction roller in the spaces between successive spheres in said first direction, and chain means interconnecting said rollers, said first means interacting with said chain means to drive the track.

17. A vehicle as claimed in claim 1 wherein said tracks are outside said vehicle, each of said tracks including a plurality of interconnected link means, and means for mounting said sphere in the link means so as to cause less than half of each sphere to project from the link means.

18. A vehicle as claimed in claim 1 wherein said means for controlling controls both the rate and directions of movement of said vehicle.

19. A vehicle as claimed in claim 1 wherein said means for controlling controls said first and second means to also control rotation of the vehicle about an axis perpendicular to both the first and second directions.

20. A device for providing controlled omnidirectional relative movement between the device and a selected surface in contact with the device comprising:

a) a first track mounted to said device;

b) a second track mounted to said device parallel to and spaced from said first track;

c) first means for independently driving said first track and said second track in a first direction;

d) a plurality of spheres mounted in each of said tracks at intervals spaced in said first direction;

e) second means for driving the spheres in at least one of said tracks to rotate in a second direction generally perpendicular to said first direction; and

means for controlling said first and second means to create relative movement in a desired direction between the device and the surface.

21. A device as claimed in claim 20 wherein the device is stationary and the surface is on a movable platform resting on the device.