Multi-spoked wheel assembly

• US 9,726,268 B1
• Filed: 12/03/2013
• Issued: 08/08/2017
• Est. Priority Date: 12/07/2012
• Status: Active Grant

• Current Assignee: United States of America as represented by the Administrator of NASA
• Original Assignee: United States Administrator of National Aeronautics and Space Administration
• Inventors: Krasowski, Michael, Greer, Lawrence
• Primary Examiner(s): Siconolfi, Robert A
• Assistant Examiner(s): Dodd, Ryan
• Application Number:
  US14/095,442
• Time in Patent Office: 1,344 Days
• Field of Search: 475334, 475325, 475311, 475313, 475337, 475339, 475319, 475288, 475346, 475903
• CPC Class Codes: A61G 5/06 with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
• CPC Class Codes: A61G 5/061 for climbing stairs
• CPC Class Codes: A61G 5/065 with three or more wheels mounted on a rotary cross member, e.g. spiders or spoked wheels with small wheels at the end of the spokes
• CPC Class Codes: F16H 1/36 with two central gears coupled by intermeshing orbital gears
• CPC Class Codes: F16H 2001/2881 comprising two axially spaced central gears, i.e. ring or sun gear, engaged by at least one common orbital gear wherein one of the central gears is forming the output
• CPC Class Codes: F16H 3/58 with sets of orbital gears, each consisting of two or more intermeshing orbital gears
• CPC Class Codes: F16H 3/663 with conveying rotary motion between axially spaced orbital gears, e.g. RAVIGNEAUX
• CPC Class Codes: F16H 37/041 for conveying rotary motion with constant gear ratio

Abstract

A robust ground traction (drive) assembly for remotely controlled vehicles, which not only operates smoothly on surfaces that are flat, but also upon surfaces that include rugged terrain, snow, mud, and sand, is provided. The assembly includes a sun gear and a braking gear. The sun gear is configured to cause rotational force to be applied to second planetary gears through a coupling of first planetary gears. The braking gear is configured to cause the assembly (or the second planetary gears) to rotate around the braking gear when an obstacle or braking force is applied.

Claims

1. An apparatus, comprising:

a sun gear rotatable about a center axis;

a plurality of first planetary gears in mesh engagement with the sun gear;

a plurality of second planetary gears each in mesh engagement with a corresponding first planetary gear;

a wheel connected to each of the plurality of second planetary gears to allow the apparatus to traverse on the wheels over the ground such that when one of the plurality of second planetary gears rotates about its axis of rotation its corresponding wheel rotates about the same axis of rotation;

wherein rotational force applied to the sun gear causes rotational force on the second planetary gears through the mesh coupling of the first planetary gears; and

a braking gear rotatable about the center axis and in mesh engagement with the plurality of second planetary gears;

where the apparatus is configured to operate in two rotational modes of operation, comprising;

a minor mode where each second planetary gear rotates about its respective axis and rotationally drives its corresponding wheel to allow the apparatus to roll on its wheels over a surface;

or

a major mode where each second planetary gear rotates about its respective axis and rotationally drives its corresponding wheel to roll over a surface as in the minor mode and also where each second planetary gear simultaneously travels rotationally around the braking gear thereby allowing the wheels to walk over a surface.

2. The apparatus of claim 1, wherein, during operation of the apparatus, the sun gear and the second planetary gears are configured to rotate in a first direction, and the braking gear and the first planetary gears are configured to rotate in a second direction.

3. The apparatus of claim 1, further comprising:

a front plate and a back plate are configured to hold the sun gear, the first planetary gears, the second planetary gears, and the braking gear to form the apparatus.

4. The apparatus of claim 1, wherein the sun gear is configured to be operated by a motor.

5. The apparatus of claim 1, wherein the braking gear is configured to be operated by a braking mechanism.

14. The apparatus of claim 1, wherein the major mode is engaged through a braking force applied to the braking gear.

15. The apparatus of claim 1, wherein the major mode is engaged when the apparatus encounters an obstacle that retards the rotational force of any second planetary gear.

16. The apparatus of claim 1, wherein the major mode is engaged passively through operator command or autonomously actuated using feedback from the assembly indicating slippage or approaching a stall state.

17. The apparatus of claim 1, wherein the major mode is engaged when the terrain is loose and traction is not good.

18. The apparatus of claim 1, wherein the major mode is engaged through fractional or modulated braking.

6. A multi-spoked assembly, comprising:

a sun gear rotatable about a center axis;

a plurality of first planetary gears in mesh engagement with the sun gear;

a plurality of second planetary gears each in mesh engagement with a corresponding first planetary gear;

a wheel connected to each of the plurality of second planetary gears to allow the apparatus to traverse on the wheels over the ground such that when one of the plurality of second planetary gears rotates about its axis of rotation its corresponding wheel rotates about the same axis of rotation;

wherein rotational force applied to the sun gear causes rotational force on the second planetary gears via the first planetary gears;

a braking gear rotatable about the center axis and in mesh engagement with the plurality of second planetary gears;

where the apparatus is configured to operate in two rotational modes of operation, comprising;

a minor mode where each second planetary gear rotates about its respective axis and rotationally drives its corresponding wheel to allow the apparatus to roll on its wheels over a surface;

or

a major mode where each second planetary gear rotates about its respective axis and rotationally drives its corresponding wheel to roll over a surface as in the minor mode and also where each second planetary gear simultaneously travels rotationally around the braking gear thereby allowing the wheels to walk over a surface;

wherein when a rotational force of the braking gear is reduced or the braking gear is prevented from moving or spinning, the plurality of second planetary gears travel around the braking gear.

7. The multi-spoked assembly of claim 6, wherein, during operation of the apparatus, the sun gear and the second planetary gears are configured to rotate in a first direction, and the braking gear and the first planetary gears are configured to rotate in a second direction.

8. The multi-spoked assembly of claim 6, further comprising:

a front plate and a back plate are configured to hold the sun gear, the first planetary gears, the second planetary gears, and the braking gear to form the apparatus.

9. The multi-spoked assembly of claim 6, wherein the sun gear is configured to be operated by a motor.

10. The multi-spoked assembly of claim 6, wherein the braking gear is configured to be controlled by a braking mechanism.

11. An apparatus, comprising:

a motor driven sun gear rotatable about a center axis;

a plurality of first planetary gears in mesh engagement with the sun gear;

a plurality of second planetary gears each in mesh engagement with a corresponding first planetary gear;

a wheel connected to each of the plurality of second planetary gears to allow the apparatus to traverse on the wheels over the ground such that when one of the plurality of second planetary gears rotates about its axis of rotation its corresponding wheel rotates about the same axis of rotation,

a braking gear rotatable about the center axis and in mesh engagement with the plurality of second planetary gears;

where the apparatus is configured to operate in two rotational modes of operation, comprising;

a minor mode wherein rotational force applied to the sun gear causes rotational force on the wheels, causing the apparatus to roll on its wheels to traverse across a surface;

or a major mode where each wheel rotates about its respective axis as in the minor mode and also simultaneously travels rotationally around the braking gear thereby allowing the wheels to walk over surfaces.

12. The apparatus of claim 11, wherein, during operation of the apparatus, the sun gear and the second planetary gears are configured to rotate in a first direction, and the braking gear and the first planetary gears are configured to rotate in a second direction.

13. The apparatus of claim 11, further comprising:

a front plate and a back plate are configured to hold the sun gear, the first planetary gears, the second planetary gears, and the braking gear to form the apparatus.