Spherical wheel drive and mounting

Patent metadata

Field	Value
Publication number	US-11001298-B2
Application number	US-201816191301-A
Country	US
Kind code	B2
Filing date	Nov 14, 2018
Priority date	Nov 15, 2017
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

Implementations relate to a spherical wheel drive and mounting. In some implementations, a wheel mechanism includes a spherical wheel, a base, and a rotary bearing coupled to the base and contacting a surface of the spherical wheel, where the rotary bearing configured to allow the spherical wheel to rotate. The wheel mechanism includes an omni wheel coupled to the base and engaged with a surface of the spherical wheel, and an actuator coupled to the base and to the omni wheel, where the actuator configured to rotate the omni wheel to cause rotation of the spherical wheel.

First claim

What is claimed is:

1. A wheel mechanism comprising:
a spherical wheel configured to contact a ground surface;
a base;
a rotary bearing coupled to the base and contacting a surface of the spherical wheel at locations of the spherical wheel on a first side of a plane that extends parallel to the ground surface through a center of the spherical wheel, the ground surface being on a second side of the plane opposite to the first side of the plane, wherein the rotary bearing is configured to provide a path for a portion of weight of a load carried by the wheel mechanism directly to the spherical wheel;
an omni wheel coupled to the base, the omni wheel being rotatable about an axis of the omni wheel and engaged with the surface of the spherical wheel; and
an actuator coupled to the base and to the omni wheel, the actuator configured to rotate the omni wheel to cause rotation of the spherical wheel;
a spring element coupled between the omni wheel and the base, the spring element providing a force on the omni wheel that biases the omni wheel against the surface of the spherical wheel, the spring element configured to isolate vibrations caused by rotation of the omni wheel against the surface of the spherical wheel.

2. The wheel mechanism of claim 1 wherein:
the rotary bearing is configured to allow the spherical wheel to rotate, and
the rotary bearing includes a ball transfer unit including a spherical ball contacting the surface of the spherical wheel.

3. The wheel mechanism of claim 1 wherein:
the omni wheel includes a plurality of rollers arranged around a circumference of the omni wheel, one or more of the plurality of rollers engaged with the surface of the spherical wheel, each roller of the plurality of rollers rotating about a respective axis of rotation that is tangential to the circumference of the omni wheel, and
the vibrations are caused by surfaces of the plurality of rollers rotating against the surface of the spherical wheel.

4. The wheel mechanism of claim 1 wherein:
the rotary bearing is one of a plurality of rotary bearings, and
the plurality of rotary bearings are coupled to the base and contact the surface of the spherical wheel at respective locations of the spherical wheel above the plane that is parallel to the ground surface.

5. The wheel mechanism of claim 4 wherein the plurality of rotary bearings are each configured to provide a path for a respective portion of the weight of the load carried by the wheel mechanism directly to the spherical wheel.

6. The wheel mechanism of claim 4 wherein the rotary bearings are spaced approximately equally around the spherical wheel.

7. The wheel mechanism of claim 4 wherein:
a first rotary bearing of the plurality of rotary bearings contacts the surface of the spherical wheel at a first position to oppose a force applied by the omni wheel against the spherical wheel,
a second rotary bearing of the plurality of rotary bearings contacts the surface of the spherical wheel at a second position closer to the base than the first position at which the first rotary bearing contacts the surface of the spherical wheel, and
the second rotary bearing transfers a greater force of the load to the spherical wheel than the first rotary bearing.

8. The wheel mechanism of claim 4 wherein:
the omni wheel is one of a plurality of omni wheels coupled to the base and engaged with the surface of the spherical wheel at respective locations of the spherical wheel on the first side of the plane, and
each rotary bearing of the plurality of rotary bearings engages the spherical wheel in a respective position to oppose a respective force applied by a particular omni wheel of the plurality of omni wheels against the surface of the spherical wheel.

9. The wheel mechanism of claim 8 wherein:
each of the omni wheels is rotatably coupled to a respective pivoting member,
each respective pivoting member is rotatably coupled to the base, and
the spring element is one of a plurality of spring elements, each spring element being coupled between each respective pivoting member and the base that biases the respective omni wheel against the surface of the spherical wheel.

10. The wheel mechanism of claim 1 wherein:
the omni wheel is rotatably coupled to a pivoting member,
the pivoting member is rotatably coupled to the base, and
the spring element is coupled between the pivoting member and the base.

11. A wheel system comprising:
a chassis; and
a plurality of wheel modules coupled to the chassis, wherein one or more wheel modules of the plurality of wheel modules includes:
a spherical wheel configured to contact a ground surface;
a base coupled to the spherical wheel via a rotary bearing that contacts a surface of the spherical wheel at locations of the spherical wheel above a plane that extends parallel to the ground surface through a center of the spherical wheel, wherein the rotary bearing is configured to provide a path for a portion of weight of a load carried by the wheel system directly to the spherical wheel;
an omni wheel coupled to the base, the omni wheel being rotatable about an axis of the omni wheel and engaged with the surface of the spherical wheel; and
an actuator coupled to the base and to the omni wheel and configured to apply rotational force to the omni wheel to cause rotation of the spherical wheel,
a spring element coupled between the omni wheel and the base, the spring element providing a force on the omni wheel that biases the omni wheel against the surface of the spherical wheel, the spring element configured to isolate vibrations caused by rotation of the omni wheel against the surface of the spherical wheel.

12. The wheel system of claim 11 wherein the plurality of wheel modules are three wheel modules.

13. The wheel system of claim 11 wherein:
the one or more wheel modules are multiple wheel modules,
the wheel system includes a respective actuator associated with each of the multiple wheel modules, and
each of the respective actuators is configured to rotate an associated spherical wheel in a different direction with respect to other wheel modules of the multiple wheel modules.

14. The wheel system of claim 11 wherein:
in each of the one or more wheel modules, the rotary bearing is one of a plurality of ball transfer units that each transmit a respective portion of the weight of the load carried by the wheeled system directly to the spherical wheel,
the plurality of ball transfer units are coupled to the base and contact the surface of the spherical wheel at respective locations of the spherical wheel above the plane, and wherein
the plurality of ball transfer units are configured to allow the spherical wheel to rotate.

15. The wheel system of claim 11 wherein, in each of the one or more wheel modules:
the rotary bearing is a first rotary bearing that contacts the surface of the spherical wheel at a first position to oppose a force applied by the omni wheel against the spherical wheel,
a second rotary bearing contacts the surface of the spherical wheel at a second position closer to the base than the first position at which the first rotary bearing contacts the surface of the spherical wheel, and
the second rotary bearing transfers a greater force of the load to the spherical wheel than the first rotary bearing.

16. The wheel system of claim 15 , wherein:
the omni wheel engages the surface of the spherical wheel above the plane,
the omni wheel includes a plurality of rollers arranged around a circumference of the omni wheel, one or more of the plurality of rollers engaged with the

Assignees

• Intuitive Surgical Operations

Inventors

• Geiger Stefan
• Carbone Joseph

Classifications

• B62D15/00 Primary

  Steering not otherwise provided for · CPC title

• B60B19/003

  Multidirectional wheels · CPC title

• B60B19/14

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

• B60K2007/003

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

• B62D11/003

  Electric or electronic control systems · CPC title