APPARATUS AND METHOD FOR CORRECTING ERROR OF GYRO SENSOR IN MOBILE ROBOT

• US 20110172820A1
• Filed: 06/26/2009
• Published: 07/14/2011
• Est. Priority Date: 07/01/2008
• Status: Active Grant

• Current Assignee: Microinfinity, Inc.
• Original Assignee: Microinfinity, Inc.
• Inventors: Ryu, Guen-Rok, Song, Jin-Woo, Kim, Do-Hyung, Chung, Hak-Young
• Granted Patent: US 9,222,801 B2
• Time in Patent Office: Days
• US Class Current: 700/254
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices
• 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

Abstract

Provided are a method and apparatus for correcting an error of a gyro sensor, and more particularly, a method and apparatus for correcting an error of a gyro sensor installed in a mobile robot.

Claims

1. An apparatus for correcting an error of a gyro sensor in a mobile robot, the apparatus comprising:

a control unit stopping or moving the mobile robot; and

a correction unit determining whether the mobile robot is stationary and correcting an error of the gyro sensor using output values obtained from the gyro sensor when the mobile robot is stationary,

wherein the correction unit comprises;

a state determination unit determining whether the mobile robot is stationary using a deviation of output values of the gyro sensor; and

a bias calculation unit calculating a bias value using output values of the gyro sensor when it is determined that the mobile robot is stationary.

2. The apparatus of claim 1, further comprising an angular velocity calculation unit calculating an angular velocity of the mobile robot by subtracting the calculated bias value from the output values of the gyro sensor.

3. The apparatus of claim 1, wherein the state determination unit determines that the mobile robot is stationary when the deviation of the output values of the gyro sensor is equal to or less than a threshold.

4. The apparatus of claim 1, wherein the bias calculation unit updates the bias value by continuously obtaining output values of the gyro sensor.

5. The apparatus of claim 4, wherein the bias calculation unit calculates the bias value using

6. A mobile robot estimating a rotation angle thereof, the mobile robot comprising:

a state determination unit determining whether the mobile robot is stationary;

a bias calculation unit calculating a bias value using output values of a gyro sensor installed in the mobile robot when the state determination unit determines that the mobile robot is stationary; and

a rotation angle estimation unit estimating the rotation angle of the mobile robot using the calculated bias value and output values of the gyro sensor when the mobile robot is moving.

7. The mobile robot of claim 6, wherein when it is determined that the mobile robot is stationary, the bias calculation unit displays information about the stationary state of the mobile robot on a display unit or dashboard of the mobile robot or on a remote control controlling the mobile robot.

8. A method of correcting an error of a gyro sensor in a mobile robot, the method comprising:

determining whether the mobile robot is stationary using a deviation of output values of the gyro sensor installed in the mobile robot;

calculating a bias value using output values of the gyro sensor when it is determined that the mobile robot is stationary; and

calculating an angular velocity of the mobile robot using an output value of the gyro sensor and the calculated bias value when the mobile robot is moving.

9. The method of claim 8, wherein in the determining of whether the mobile robot is stationary, the mobile robot is determined to be stationary when a standard deviation or variance of a predetermined number of output values of the gyro sensor or the standard deviation or variance of values output from the gyro sensor for a predetermined period of time is equal to or less than a threshold.

10. The method of claim 8, wherein in the calculating of the bias value, the bias value is calculated as a representative value for output values obtained from the gyro sensor when it is determined that the mobile robot is stationary, wherein the representative value is continuously updated using output values obtained from the gyro sensor while the mobile robot is determined to be stationary.

11. The method of claim 8, further comprising updating the calculated bias value by determining whether the mobile robot is stationary and calculating a new bias value of the mobile robot when it is determined that the mobile robot is stationary.