Ball-balancing robot and drive assembly therefor

Patent metadata

Field	Value
Publication number	US-10189342-B2
Application number	US-201615549520-A
Country	US
Kind code	B2
Filing date	Feb 9, 2016
Priority date	Feb 9, 2015
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

A ball-balancing drive assembly includes a ball having a ball surface and a reference axis extending through a centroid of the ball. Three omniwheel assemblies, each having a motor with a motor axle and an omniwheel configured to rotate around the motor axle are mounted on a chassis configured for supporting the three omniwheel assemblies at radially symmetric spacings with the motor axles oriented at an angle relative to the reference axis and the omniwheels oriented in mutually-orthogonal planes. Each omniwheel frictionally contacts the ball surface to convert rotational motion of the motor axle to torque on the ball.

First claim

The invention claimed is:

1. A ball-balancing drive assembly, comprising:
a ball having a ball surface and a reference axis extending through a centroid of the ball;
three omniwheel assemblies, each omniwheel assembly comprising a motor having a motor axle and an omniwheel configured to rotate around the motor axle;
a chassis configured for supporting the three omniwheel assemblies at radially symmetric spacings with the motor axles oriented at an angle relative to the reference axis and the omniwheels oriented in mutually-orthogonal planes, wherein each omniwheel frictionally contacts the ball surface to convert rotational motion of the motor axle to torque on the ball.

2. The ball-balancing drive assembly of claim 1 , wherein the ball surface has an equator corresponding to a plane perpendicular to the reference axis that bisects the ball, wherein the omniwheels frictionally contact the ball surface within a mid-latitude range near the equator.

3. The ball-balancing drive assembly of claim 2 , wherein the mid-latitude range comprises 20° N to 30° N of the equator.

4. The ball-balancing drive assembly of claim 1 , wherein angle relative to the reference axis is within a range of 45° to 80°.

5. The ball-balancing drive assembly of claim 1 , wherein the angle relative to the reference axis is within a range of 60° to 70°.

6. The ball-balancing drive assembly of claim 1 , wherein the omniwheels are oriented mutually-orthogonally within a range of 35° to 55°.

7. The ball-balancing drive assembly of claim 1 , wherein the omniwheels are oriented mutually-orthogonally within a range of 48° to 52°.

8. The ball-balancing drive assembly of claim 1 , wherein the omniwheels are single row omniwheels.

9. The ball-balancing drive assembly of claim 1 , wherein the omniwheels are double row omniwheels.

10. The ball-balancing drive assembly of claim 1 , further comprising a frame extending from the chassis, the frame configured for supporting a power supply.

11. The ball-balancing drive assembly of claim 1 , further comprising a controller for selectively and independently activating each omniwheel assembly.

12. A ball-balancing robot, comprising:
a ball having a ball surface and a reference axis extending through a centroid of the ball;
three omniwheel assemblies, each omniwheel assembly comprising a motor having a motor axle and an omniwheel configured to rotate around the motor axle;
a chassis configured for supporting the three omniwheel assemblies at 120° spacings with the motor axles oriented at an angle a relative to the reference axis and the omniwheels rotated at an angle β to define mutually-orthogonal planes, wherein each omniwheel frictionally contacts the ball surface to convert rotational motion of the motor axle to torque on the ball;
a frame extending upward from the chassis;
a control assembly disposed on the frame, the control assembly comprising an electronic controller for selectively and independently activating the omniwheel assemblies; and
a power supply for powering the motors and the control assembly.

13. The ball-balancing robot of claim 12 , wherein the ball surface has an equator corresponding to a plane perpendicular to the reference axis that bisects the ball, wherein the omniwheels frictionally contact the ball surface within a mid-latitude range near the equator.

14. The ball-balancing robot of claim 13 , wherein the mid-latitude range comprises 20° N to 30° N of the equator.

15. The ball-balancing robot of claim 12 , wherein angle α is within a range of 45° to 80°.

16. The ball-balancing robot of claim 12 , wherein the angle β is within a range of 35° to 55°.

17. The ball-balancing robot of claim 12 , wherein the angle α and the angle β are selected as an angle pair from the pairs consisting of

α

45°
60°
70°
80°

β
35.237°
48.186°
52.082°
54.145°

18. The ball-balancing robot of claim 12 , wherein the omniwheels are single row omniwheels.

19. The ball-balancing robot of claim 12 , wherein the omniwheels are double row omniwheels.

20. The ball-balancing robot of claim 12 , further comprising an outer skin configured for enclosing at least of portion of the frame, control assembly and power supply.

Assignees

• Univ California

Inventors

• Bewley Thomas R
• Friesen Jeffrey M
• Sihite Eric
• Yang Daniel

Classifications

• B60K1/02 Primary

  comprising more than one electric motor · CPC title

• B60K2007/003

  with two or more motors driving a single wheel · CPC title

• B60B33/08

  Ball castors {(B60B33/0028 takes precedence)} · CPC title

• B60B19/14 Primary

  Ball-type wheels (B60B19/06 takes precedence) · CPC title

• B25J5/00

  Manipulators mounted on wheels or on carriages (B25J1/00 takes precedence; programme-controlled manipulators B25J9/00 {; vehicle aspects B60, B62, e.g. remote-controlled steering for motor vehicles B62D1/24; control of position of vehicles G05D1/00}) · CPC title