Mobile robot platform and method for sensing movement of the same

• US 7,747,349 B2
• Filed: 03/22/2006
• Issued: 06/29/2010
• Est. Priority Date: 12/26/2005
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Tu, Mao-Feng, Tseng, Kuo-Shih, Chen, Meng-Chun, Yeh, Syh-Shiuh
• Primary Examiner(s): Tran; Khoi
• Assistant Examiner(s): Figueroa; Jaime
• Application Number:
  US11/385,797
• Publication Number:
  US 20070150096A1
• Time in Patent Office: 1,560 Days
• Field of Search: 180/20, 180/21, 180/252, 180/253, 280/124.114, 700/245
• US Class Current: 700/245
• CPC Class Codes: B25J 5/007 mounted on wheels
• CPC Class Codes: G05D 1/0259 using magnetic or electromagnetic means
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00

Abstract

A mobile robot platform and a method for sensing movement of the same are disclosed, which utilize two omni-directional meter wheels perpendicular to each other and a magnetic sensing module for detecting a moving condition of the platform moving on a planar surface while transmitting the detected moving condition to a signal processing unit to calculate the position, velocity, angular position and angular velocity of the platform.

Claims

1. A mobile robot platform, comprising:

a frame;

at least an omni-directional meter wheel, being arranged on the frame, each further comprising;

an omni-directional wheel;

a side support, coupled to the omni-directional wheel by a bearing; and

a rotary encoder, coupled to the omni-directional wheel by the bearing, for issuing a pulse signal with respect to the rotation of the omni-directional meter wheel;

a magnetic sensing module, arranged on the frame, capable of issuing a bit signal with respect to the variation of geomagnetic strength; and

a signal processing unit, for processing the bit signal and the pulse signal.

2. The mobile robot platform of claim 1, wherein a plurality of rollers are arranged on the frame.

3. The mobile robot platform of claim 2, wherein a power driving unit is arranged on the frame for driving the plural rollers to rotate.

4. The mobile robot platform of claim 1, wherein each omni-directional meter wheel further comprises an elastic member for buffering the vibrations caused when the rotating omni-directional wheel comes into contact with ground.

5. The mobile robot platform of claim 1, wherein the magnetic sensing module is an electrical compass.

6. The mobile robot platform of claim 1, wherein the signal processing unit, further comprising:

at least a decoder, for decoding the pulse signal and generating a count signal accordingly; and

a position unit, for performing a position calculation upon the count signal to generate a position signal accordingly.

7. The mobile robot platform of claim 1, wherein the signal processing unit, further comprising:

at least a decoder, for decoding the pulse signal and generating a count signal accordingly;

at least a difference operator, for performing a calculation of difference upon the count signal to generate a difference signal accordingly; and

a velocity unit, for performing a velocity calculation upon the difference signal to generate a velocity signal accordingly.

8. The mobile robot platform of claim 1, wherein the signal processing unit, further comprising:

at least a decoder, for decoding the bit signal and generating a digital signal accordingly;

an orientation unit, for performing an orientation calculation upon the digital signal to generate an angular position signal accordingly.

9. The mobile robot platform of claim 1, wherein the signal processing unit, further comprising:

at least a decoder, for decoding the bit signal and generating a digital signal accordingly;

at least a difference operator, for performing a calculation of difference upon the digital signal to generate a difference signal accordingly; and

a rotation unit, for performing a rotation calculation upon the digital signal to generate an angular speed signal accordingly.

10. The mobile robot platform of claim 1, wherein the signal processing unit, further comprising:

a central control unit, for monitoring moving conditions of the frame.

11. A method for sensing movements of a moving mobile robot platform, comprising the steps of:

providing a first omni-directional meter wheel and a second omni-directional meter wheel, each of which comprising an omni-directional wheel, a side support, and a rotary encoder for issuing a pulse signal with respect to the rotation of the omni-directional meter wheel, wherein both the side support and the rotary encoder are coupled to the omni-directional wheel by one bearing;

decoding a pulse signal issued by the first omni-directional meter wheel to generate a first count signal while decoding another pulse signal issued by the second omni-directional meter wheel to generate a second count signal;

performing a position calculation upon the first count signal and the second count signal to generate a position signal;

performing a calculation of difference upon the first count signal to generate a first difference signal while performing a calculation of difference upon the second count signal to generate a second difference signal; and

performing a velocity calculation upon the first difference signal and the second difference signal to generate a velocity signal.

12. The method claim 11, further comprising the steps of:

providing a magnetic sensing module;

decoding a bit signal issued by the magnetic sensing module to generate a digital signal;

performing an orientation calculation upon the digital signal to generate an angular position signal;

performing a calculation of difference upon the digital signal to generate a difference signal; and

performing a rotation calculation upon the difference signal to generate an angular velocity signal.

13. The method claim 12, wherein the first omni-directional meter wheel, the second omni-directional meter wheel and the magnetic sensing module are arranged on a frame of the mobile robot platform.

14. The method claim 13, wherein the first omni-directional meter wheel is orientated to perpendicular to the second omni-directional meter wheel.

15. The method claim 13, wherein the magnetic sensing module is an electrical compass.

16. The method claim 13, wherein the frame further comprises a signal processing unit for receiving the pulse signal of the first omni-directional meter wheel, the pulse signal of the second omni-directional meter wheel and the bit signal of the magnetic sensing module.

17. The method claim 16, wherein the signal processing unit, further comprising:

at least a decoder;

at least a difference operator;

a position unit;

a velocity unit;

an orientation unit;

a rotation unit; and

a central control unit.

18. The method claim 17, wherein each decoder is used for performing the decoding operation.

19. The method claim 17, wherein each difference operator is used for performing the calculation of difference.

20. The method claim 17, wherein the position unit is used for performing the position calculation to obtain the position of the frame of the mobile robot platform.

21. The method claim 17, wherein the velocity unit is used for performing the velocity calculation to obtain the velocity of the frame of the mobile robot platform.

22. The method claim 17, wherein the orientation unit is used for performing the orientation calculation to obtain the angular position of the frame of the mobile robot platform.

23. The method claim 17, wherein the rotation unit is used for performing the rotation calculation to obtain the angular velocity of the frame of the mobile robot platform.

24. The method claim 17, wherein the central control unit is used for receiving the position signal, the velocity signal, the angular position signal and the angular velocity signal so as to monitor the moving condition of the frame of the mobile robot platform.