MOVING APPARATUS AND METHOD OF SELF-DIRECTION TESTING AND SELF-DIRECTION CORRECTION THEREOF

• US 20080172150A1
• Filed: 06/04/2007
• Published: 07/17/2008
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Yu, Hung-Hsiu, Wang, Wei-Han, Huang, Hsuan-Kuan, Liu, Ching-Yi
• Granted Patent: US 7,444,215 B2
• Time in Patent Office: Days
• US Class Current: 701/23
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• 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 moving apparatus has a body, and has at least a pair of wheels, a control unit, a direction measuring unit and at least a pair of encoders installed on the body. The direction measuring unit coupled to the control unit measures the direction of the body, and the control unit obtains a first direction variation according to the direction information. The pair of encoders coupled to the control unit measure a speed of the pair of wheels, and the control unit obtains a second direction variation according to information of the speed. The control unit compares the first and second direction variations to determine whether the direction measuring unit is temporarily dysfunction. Based on the result of comparison, the control unit applies the information provided by the direction measuring unit or the pair of encoders to obtain the current direction of the body.

Claims

1. A moving apparatus, having self-direction testing and self-direction correction functions, comprising:

a body;

at least one pair of wheels, installed on the body, for changing a direction of the body;

a control unit, installed on the body;

a direction measuring unit, installed on the body and coupled to the control unit, for measuring the direction of the body and transmitting direction information to the control unit for obtaining a first direction variation of the body according to the direction information; and

at least one pair of encoders, installed on the body and coupled to the control unit, for measuring a speed of the pair of the wheels respectively and transmitting information of the speed to the control unit for obtaining a second direction variation of the body according to the information of the speed, wherein during a process of changing a current direction of the body to a target direction through the pair of the wheels, the control unit determines whether the direction measuring unit is temporarily dysfunction by comparing the first direction variation with the second direction variation, wherein

if the direction measuring unit is determined to be normal, the control unit obtains the current direction of the body according to the direction information provided by the direction measuring unit, and

if the direction measuring unit is determined to be abnormal, the control unit obtains the current direction of the body according to the information of the speed provided by the pair of the encoders.

2. The moving apparatus as claimed in claim 1, wherein the direction measuring unit is an electronic compass or a gyroscope.

3. The moving apparatus as claimed in claim 1, wherein the process of comparing the first direction variation with the second direction variation is by determining whether an absolute value of a difference between the first direction variation and the second direction variation is greater than a predetermined value.

4. The moving apparatus as claimed in claim 1, further comprising:

a warning device, installed on the body and coupled to the control unit, wherein when the direction measuring unit is determined to be abnormal, the control unit outputs a signal to the warning device for sending out a warning message.

5. The moving apparatus as claimed in claim 1, further comprising:

a wireless module, installed on the body and coupled to the control unit, wherein when the direction measuring unit is determined to be abnormal, the control unit outputs a signal to the wireless module for sending out a wireless warning signal to a remote monitoring interface.

6. The moving apparatus as claimed in claim 1, further comprising:

a pair of drive units, installed on the body and coupled to the control unit, for driving the pair of the wheels respectively.

7. A method of self-direction testing and self-direction correction, applicable for a moving apparatus, comprising:

(1) changing a current direction of a body of the moving apparatus to a target direction through a pair of wheels of the moving apparatus according to a direction-changing instruction;

(2) during the process of changing the current direction of the body to the target direction through the pair of the wheels, obtaining a first direction variation of the body in a predetermined cycle through a direction measuring unit of the moving apparatus, and measuring a speed of the pair of the wheels respectively through a pair of encoders of the moving apparatus, so as to obtain a second direction variation of the body in the predetermined cycle;

(3) comparing the first direction variation with the second direction variation to determine whether the direction measuring unit is temporarily dysfunction, wherein

if the direction measuring unit is determined to be normal, the current direction of the body is obtained according to direction information provided by the direction measuring unit, and

if the direction measuring unit is determined to be abnormal, the current direction of the body is obtained according to information of the speed provided by the pair of the encoders;

(4) if the current direction of the body is obtained according to the direction information provided by the direction measuring unit, determining whether the current direction of the body is changed to the target direction, wherein

if the current direction of the body has not been changed to the target direction, Steps (2)-(3) are repeated, and

if the current direction of the body has already been changed to the target direction, the pair of the wheels stop changing the current direction of the body; and

(5) if the current direction of the body is obtained according to information of the speed provided by the pair of the encoders, determining whether the current direction of the body is changed to the target direction, wherein if the current direction of the body has not changed to the target direction, the current direction of the body continues to be obtained according to information of the speed of the encoders, and the pair of the wheels do not stop changing the current direction until the current direction is changed to the target direction.

8. The method of self-direction testing and self-direction correction as claimed in claim 7, wherein the direction measuring unit employs an electronic compass or a gyroscope.

9. The method of self-direction testing and self-direction correction as claimed in claim 7, wherein the step of comparing the first direction variation with the second direction variation is by determining whether an absolute value of a difference between the first direction variation and the second direction variation is greater than a predetermined value.

10. The method of self-direction testing and self-direction correction as claimed in claim 7, further comprising:

if the direction measuring unit is determined to be abnormal, sending out a warning message by a warning device of the moving apparatus.

11. The method of self-direction testing and self-direction correction as claimed in claim 7, further comprising:

if the direction measuring unit is determined to be abnormal, sending a wireless warning signal to a remote monitoring interface by a wireless module of the moving apparatus.

12. The method of self-direction testing and self-direction correction as claimed in claim 7, wherein the step of changing a direction of the body through the pair of the wheels is by driving the pair of the wheels respectively through a pair of drive units of the moving apparatus to change the direction of the body.