Cleaning robot

• US 10,362,917 B2
• Filed: 09/06/2016
• Issued: 07/30/2019
• Est. Priority Date: 12/04/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yoo, Jeong Ki, Park, Sung Jin, Lee, Jun Young, Shin, Dong Min, Lee, Dong Hun, Jeong, Jae Youl, Kim, Shin, Park, Heum Yong, Na, In Hak
• Primary Examiner(s): Redding, David
• Application Number:
  US15/257,204
• Publication Number:
  US 20160374527A1
• Time in Patent Office: 1,057 Days
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4041 Roll shaped surface treating tools
• CPC Class Codes: A47L 11/4061 Steering means; Means for avoiding obstacles; Details related to the place where the driver is accommodated
• CPC Class Codes: A47L 11/4066 Propulsion of the whole machine
• CPC Class Codes: A47L 11/4072 Arrangement of castors or wheels
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 9/009 Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles
• 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 cleaning robot includes a main body and a drive unit to move the main body. The drive unit includes a plurality of motors to generate driving force; a plurality of wheels connected to one of the plurality of motors and rotating by driving force received from the one of the plurality of motors; and a driving frame to support the plurality of wheels, receive driving force from another motor among the plurality of motors, and rotate for changing positions of the plurality of wheels.

Claims

1. A cleaning robot comprising a main body and a drive unit to move the main body, further comprising:

an input unit to input a motion instruction for the cleaning robot;

a tilt sensor to measure an inclination of the cleaning robot moving in accordance with the input motion instruction; and

a controller to determine a stuck state of the cleaning robot by using an angle value obtained by measuring an angle the cleaning robot has moved based on sensor information of the tilt sensor.

2. The cleaning robot according to claim 1, wherein the drive unit further comprises a left driving motor and a right driving motor to transmit driving force to left and right sides of the main body, and

the cleaning robot further comprises a first encoder installed in the left driving motor to measure an amount of movement of the left driving motor generated by the motion instruction for the cleaning robot, and a second encoder installed in the right driving motor to measure an amount of movement of the right driving motor generated by the motion instruction for the cleaning robot.

3. The cleaning robot according to claim 2, wherein the tilt sensor is a gyro sensor to measure an inclination value the cleaning robot has actually moved.

4. The cleaning robot according to claim 3, wherein the controller calculates an angle the cleaning robot has moved based on measurements of the first encoder and the second encoder encoders, measures an angle the cleaning robot has moved based on sensor information of the tilt sensor, and determines a stuck state of the cleaning robot by using a difference between the calculated angle of the cleaning robot and the measured angle of the cleaning robot.

5. The cleaning robot according to claim 4, wherein the controller calculates first encoder and the second encoder encoder variations A1 and A2 the cleaning robot has moved based on the measurements of the first and second encoders, calculates an inclination value variation B the cleaning robot has moved based on the sensor information of the tilt sensor, and determines a degree of risk and type of the stuck state of the cleaning robot by using the calculated first and second encoder variations A1 and A2 and the calculated inclination value variation B.

6. The cleaning robot according to claim 5, wherein the controller determines that the cleaning robot is in a low risk ‘

lifted stated’

when at least one of the first and second encoder variations A1 and A2 is greater than a first encoder threshold (A_th1=V+V*0.06), and the inclination value variation B is greater than a first inclination threshold (B_th1=±

3°

),

wherein in the first encoder threshold A_th1, V is an average velocity of the cleaning robot.

7. The cleaning robot according to claim 6, wherein the controller decelerates the left driving motor and the right driving motor motors to enable the cleaning robot to escape from the low risk ‘

lifted state’ and

provides information suitable for escaping from the ‘

lifted state’

.

8. The cleaning robot according to claim 5, wherein the controller determines that the cleaning robot is in a low risk upper portion ‘

jammed stated’

when at least one of the first and second encoder variations A1 and A2 is less than a first encoder threshold (A_th1=V+V*0.06), and the inclination value variation B is greater than a first inclination threshold (B_th1=±

3°

),

wherein in the first encoder threshold A_th1, V is an average velocity of the cleaning robot.

9. The cleaning robot according to claim 8, wherein the controller decelerates the left driving motor and the right driving motor to enable the cleaning robot to escape from the low risk upper portion ‘

jammed state’ and

provides information suitable for escaping from the upper portion ‘

jammed state’

.

10. The cleaning robot according to claim 4, wherein the controller determines the stuck state of the cleaning robot by detecting the difference between the calculated angle of the cleaning robot and the measured angle of the cleaning robot for a predetermined time period.

11. The cleaning robot according to claim 10, wherein the controller calculates first encoder and the second encoder encoder variations A1_t1 and A2_t1 the cleaning robot has moved for a first time period t1 based on the measurements of the first and second encoders, calculates an inclination value variation B the cleaning robot has moved based on the sensor information of the tilt sensor, and determines a degree of risk and type of the stuck state of the cleaning robot by using the calculated first and second encoder variations A1_t1 and A2_t1 and the calculated inclination value variation B.

12. The cleaning robot according to claim 11, wherein the controller determines that the cleaning robot is in a low risk ‘

object-caught state’

when at least one of the first and second encoder variations A1_t1 and A2_t1 is less than a first encoder threshold (A_th1=V+V*0.06), and the inclination value variation B is greater than a reference threshold B_s of the upper portion jammed state,

wherein in the first encoder threshold A_th1, V is an average velocity of the cleaning robot.

13. The cleaning robot according to claim 12, wherein the controller decelerates the left driving motor and the right driving motor to enable the cleaning robot to escape from the low risk “

object-caught state’ and

provides information suitable for escaping from ‘

object-caught state’

.

14. The cleaning robot according to claim 4, wherein the controller determines that the cleaning robot is in a high risk ‘

lifted state’

when at least one of the first and second encoder variations A1 and A2 indicates an idle state, and the inclination value variation B is greater than a second inclination threshold (B_th2=tan−

1 (2r/h)),

wherein in the second inclination threshold B_th2, r is a radius of the main wheel and h is a ride height of the cleaning robot.

15. The cleaning robot according to claim 14, wherein the controller stops the left driving motor and the right driving motor to enable the cleaning robot to escape from the high risk ‘

lifted state’ and

provides information suitable for escaping from the ‘

lifted state’

.

16. The cleaning robot according to claim 5, wherein the controller determines that the cleaning robot is in a high risk upper portion ‘

jammed stated’

when at least one of the first and second encoder variations A1 and A2 is less than a first encoder threshold (A_th1=V+V*0.06) and greater than a second encoder threshold A_th2, and the inclination value variation B is greater than a first inclination threshold (B_th1=±

3°

),

wherein in the first encoder threshold A_th1, V is an average velocity of the cleaning robot.

17. The cleaning robot according to claim 16, wherein the controller stops the left driving motor and the right driving motor to enable the cleaning robot to escape from the high risk upper portion ‘

jammed state’ and

provides information suitable for escaping from the upper portion ‘

jammed state’

.

18. The cleaning robot according to claim 10, wherein the controller calculates first and second encoder variations A1_t2 and A2₁₂ the cleaning robot has moved for a second time period t2 based on the measurements of the first and second encoders, calculates an inclination value variation B the cleaning robot has moved based on the sensor information of the tilt sensor, and determines a degree of risk and type of the stuck state of the cleaning robot by using the calculated first and second encoder variations A1_t2 and A2₁₂ and the calculated inclination value variation B.

19. The cleaning robot according to claim 18, wherein the controller determines that the cleaning robot is in a high risk ‘

object-caught state’

when at least one of the first and second encoder variations A1_t2 and A2₁₂ is less than a first encoder threshold (A_th1=V+V*0.06), and the inclination value variation B is greater than a reference threshold B_s of the upper portion jammed state,

wherein in the first encoder threshold A_th1, V is an average velocity of the cleaning robot.

20. The cleaning robot according to claim 19, wherein the controller stops the left driving motor and the right driving motor to enable the cleaning robot to escape from the high risk “

object-caught state’ and

provides information suitable for escaping from the ‘

object-caught state’

.