System and method for inducing motion in a rolling robot using a dual telescoping linear actuator

Patent metadata

Field	Value
Publication number	US-10472008-B2
Application number	US-201615567782-A
Country	US
Kind code	B2
Filing date	Apr 20, 2016
Priority date	Apr 20, 2015
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

An embodiment is developed for a cylindrically shaped, elliptical rolling robot that has the ability to morph its outer surface as it rolls. The morphing actuation alters lengths of the major and minor axes, resulting in a torque imbalance that rolls the robot along faster or brakes its motion. A control scheme is implemented, whereby angular position and horizontal velocity are used as feedback to trigger and define morphing actuation. A goal of the control scheme is to cause the robot to follow a given velocity profile comprised of steps and ramps. Equations of motion for the rolling robot are formulated, which include rolling resistance torque caused by deformation of the outer surface tread. A computer program solves the equations of motion, and resulting plots show that by automatically morphing its shape in a periodic fashion, the rolling robot is able to commence from an initial position, achieve constant average velocity and slow itself.

First claim

What is claimed is:

1. A rolling robot, comprising:
(a) a flexible hollow cylindrical shell, said shell having an interior;
(b) a dual telescoping linear actuator positioned within said shell, said linear actuator comprising
(1) a telescoping rack column having a first end and a second end, said rack column having a rack gear attached thereto, said rack column spanning said interior of said shell, said first and second rack column ends being in mechanical communication with said shell,
(2) a telescoping pinion column having a first end and a second end, said pinion column, said pinion column spanning said interior of said shell, said first and second pinion column ends being in mechanical communication with said shell,
(3) a pinion gear positioned to engage said rack gear, and,
(4) a servomotor in mechanical communication with said pinion gear and with said pinion column, said servomotor at least for rotating said pinion gear to extend and contract said linear actuator;

(c) a first sensor for measuring an angular position of said shell;
(d) a second sensor for measuring a velocity of said shell; and,
(e) a CPU in electrical communication with said first sensor, said second sensor, and said servomotor, said CPU reading signals from said first and second sensors and using said signals to direct said servomotor to expand or contract said linear actuator, thereby altering a shape of said cylindrical shell to effect lateral motion.

2. The rolling robot according to claim 1 , wherein said rack column and said pinion column are parallel.

3. The rolling robot according to claim 1 , wherein said servomotor is affixed to said pinion column.

4. The rolling robot according to claim 1 , wherein said servomotor is an electric DC servo motor.

5. The rolling robot according to claim 1 , wherein said first sensor and said second sensor are a same sensor.

6. The rolling robot according to claim 5 , wherein said same sensor is a 3D accelerometer.

7. The rolling robot according to claim 1 , wherein said first sensor is a gyroscope.

8. A dual telescoping linear actuator, comprising
(a) a telescoping rack column having a first end and a second end, wherein
said first end of said rack column terminates in a first end-joint,
said second end of said rack column terminates in a second end-joint, and
said rack column has a rack gear attached thereto;

(b) a telescoping pinion column parallel to said rack column, said pinion column having a first end and a second end, wherein,
said first end of said pinion column terminates in said first end-joint,
said second end of said pinion column terminates in said second end-joint;

(c) a pinion gear positioned to engage said rack gear, and,
(d) a servomotor in mechanical communication with said pinion gear and with said pinion column, said servomotor at least for rotating said pinion gear to extend and contract said linear actuator.

9. The rolling robot according to claim 8 , wherein said servomotor is affixed to said pinion column.

10. The rolling robot according to claim 8 , wherein said servomotor is an electric DC servo motor.

11. A method of altering a movement condition of a rolling robot having a flexible elliptical exterior shell, said shell having two changeable elliptical axes associated therewith, comprising the steps of:
a. determining an angular position of said rolling robot with respect to said elliptical axes;
b. determining an angular velocity of said rolling robot;
c. using said angular position and said angular velocity to change a length of each of said two elliptical axes to create a torque imbalance in said robot, thereby changing said movement condition of said rolling robot.

12. The method of altering a movement condition of a rolling robot according to claim 11 , wherein said changed movement condition is an acceleration of said rolling robot.

13. The method of altering a movement condition of a rolling robot according to claim 11 , wherein said changed movement condition is a deceleration of said rolling robot.

14. The method of altering a movement condition of a rolling robot according to claim 11 , steps (a) through (c) are performed a plurality of different times.

Assignees

• Univ Oklahoma State

Inventors

• Rehm Kelly
• Puopolo Michael Gerald

Classifications

• B60Y2200/80

  Other vehicles not covered by groups B60Y2200/10 - B60Y2200/60 · CPC title

• B60B19/04

  expansible · CPC title

• B60Y2200/40

  Special vehicles · CPC title

• B60B19/02

  convertible, e.g. from road wheel to rail wheel; Wheels specially designed for alternative use on road and rail · CPC title

• B62D57/00 Primary

  Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track (sledges B62B; motor sledges B62M) · CPC title