Robot cleaner system and method of controlling the same

• US 20080004751A1
• Filed: 04/27/2007
• Published: 01/03/2008
• Est. Priority Date: 06/28/2006
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Chung, Woo Ram, Joo, Jae Man, Hong, Jun Pyo, Kim, Yong Tae, Wee, Hoon, Kim, Dong Won
• Application Number:
  US11/790,896
• Publication Number:
  US 20080004751A1
• Time in Patent Office: Days
• US Class Current: 700/258
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• 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
• CPC Class Codes: G05D 1/028 using a RF signal

Abstract

A robot cleaner system and a control method thereof reduce manufacturing costs, expand a detected distance, and precisely control a movement and positioning of a robot cleaner. The robot cleaner system includes a robot cleaner and a station. One of the robot cleaner and the station transmits a signal of a predetermined frequency and the other receives the signal so that a direction toward the transmitting side for transmitting the signal is detected based on a Doppler shift observed by the receiving side that receives the signal.

Claims

1. A robot cleaner system comprising:

a robot cleaner; and

a station;

wherein one of the robot cleaner and the station transmits a signal of a predetermined frequency and the other receives the signal so that a direction toward a transmitting side for transmitting the signal is detected based on a Doppler shift observed by a receiving side for receiving the signal.

2. The robot cleaner system according to claim 1, wherein the station comprises a transmitter to transmit the signal of the predetermined frequency,

the robot cleaner comprises a movable receiving unit installed to receive the signal transmitted from the transmitter of the station and to observe the Doppler shift of the received signal, and

a direction of the station is detected based on the Doppler shift observed by the receiving unit.

3. The robot cleaner system according to claim 2, wherein the receiving unit comprises an antenna to receive the signal transmitted from the station.

4. The robot cleaner system according to claim 3, wherein movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track in which the robot cleaner rotates in a stopped state.

5. The robot cleaner system according to claim 3, wherein the receiving unit further comprises a rotation body provided to rotate in the robot cleaner and in which the antenna is installed, and

movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

6. The robot cleaner system according to claim 3, wherein movement of the receiving unit is movement of the antenna along a traveling track of the robot cleaner in which the robot cleaner travels by a predetermined displacement.

7. The robot cleaner system according to claim 3, wherein the receiving unit further comprises:

a frequency detector to detect the frequency of the signal received by the receiving unit; and

a direction detector to detect a direction in which the station is positioned by comparing the frequency detected by the frequency detector and the frequency of the signal transmitted from the station and to generate direction information.

8. The robot cleaner system according to claim 7, wherein the direction detector determines a direction indicated by the antenna when the Doppler shift is not observed from the frequency detected by the frequency detector as the direction in which the station is positioned.

9. The robot cleaner system according to claim 3, wherein, when the Doppler shift is observed as the antenna moves along one of a rotation track of the robot cleaner and a rotation track of the rotation body, an angle θ

₁, between a forward direction of the robot cleaner and a direction in which the station is positioned is expressed by the following formula,

10. The robot cleaner system according to claim 3, wherein, when the Doppler shift is observed as the antenna moves by a traveling track along a predetermined displacement of the robot cleaner, an angle θ

₂ between the forward direction of the robot cleaner and the direction in which the station is positioned is expressed by the formula,

11. The robot cleaner system according to claim 3, wherein, when a number of the antenna is two or more, the antennas are installed at predetermined intervals.

12. The robot cleaner system according to claim 1, wherein the station comprises a docking station to charge the robot cleaner and discharge foreign substances.

13. A control method of a robot cleaner system comprising a robot cleaner and a station, the control method comprising:

transmitting a signal of a predetermined frequency from one of the robot cleaner and the station wherein the signal is received by the other; and

detecting a direction of a position of a transmitting side that transmits the signal based on a Doppler shift observed by a receiving side that receives the signal.

14. The control method of a robot cleaner system according to claim 13, wherein the station transmits the signal of the predetermined frequency via a transmitter,

the robot cleaner receives the signal transmitted from the station via a receiving unit,

the receiving unit determines whether the Doppler shift is observed, and

the direction in which the station is positioned is detected based on the observation of the Doppler shift.

15. The control method of a robot cleaner system according to claim 14, wherein the receiving unit comprises an antenna to receive the signal transmitted from the station.

16. The control method of a robot cleaner system according to claim 15, wherein movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track in which the robot cleaner rotates in a stopped state.

17. The control method of a robot cleaner system according to claim 15, wherein the receiving unit further comprises a rotation body provided to rotate in the robot cleaner and in which the antenna is installed, and

movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

18. The control method of a robot cleaner system according to claim 15, wherein movement of the receiving unit is movement of the antenna along a traveling track of the robot cleaner in which the robot cleaner travels by a predetermined displacement.

19. The control method of a robot cleaner system according to claim 15, wherein the direction detector determines a direction indicated by the antenna when the Doppler shift is not observed from the frequency detected by the frequency detector as the direction in which the station is positioned.

20. The control method of a robot cleaner system according to claim 15, wherein when the Doppler shift is observed as the antenna moves along one of a rotation track of the robot cleaner and a rotation track of the rotation body, an angle θ

₁ between a forward direction of the robot cleaner and a direction in which the station is positioned is expressed by the following formula,

21. The control method of a robot cleaner system according to claim 15, wherein, when the Doppler shift is observed as the antenna moves by a traveling track along a predetermined displacement of the robot cleaner, an angle θ

₂ between the forward direction of the robot cleaner and the direction in which the station is positioned is expressed by the formula,

22. A robot cleaner system comprising:

a robot cleaner to transmit a signal of a predetermined frequency; and

a station comprising a movable receiving unit to receive the signal transmitted from the robot cleaner, to observe a Doppler shift of the received signal, and to detect a direction in which the robot cleaner is positioned and a distance from the robot cleaner based on the Doppler shift observed by the receiving unit.

23. The robot cleaner system according to claim 22, wherein the receiving unit comprises an antenna to receive the signal transmitted from the robot cleaner.

24. The robot cleaner system according to claim 23, wherein the receiving unit further comprises a rotation body provided to rotate in the station and in which the antenna is installed, and

movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

25. The robot cleaner system according to claim 23, wherein the receiving unit further comprises:

a frequency detector to detect the frequency of the signal received by the receiving unit; and

a direction detector to detect a direction in which the station is positioned by comparing the frequency detected by the frequency detector and the frequency of the signal transmitted from the robot cleaner and to generate direction information.

26. The robot cleaner system according to claim 25, wherein the direction detector determines a direction indicated by the antenna when the Doppler shift is not observed from the frequency detected by the frequency detector as the direction in which the robot cleaner is positioned.

27. The robot cleaner system according to claim 23, wherein, when the Doppler shift is observed as the antenna moves along a rotation track of the rotation body, an angle θ

₁ between a direction indicated by the antenna and a direction in which the robot cleaner is positioned is expressed by the following formula,

28. The robot cleaner system according to claim 23, wherein a distance R from a central point of the receiving unit to a transmitter of the robot cleaner is expressed by the following formula,

29. The robot cleaner system according to claim 23, wherein, when a number of the antenna is two or more, the antennas are installed at predetermined intervals.

30. The robot cleaner system according to claim 22, wherein the station comprises a docking station to charge the robot cleaner and discharge foreign substances.

31. A control method of a robot cleaner system comprising:

transmitting a signal of a predetermined frequency from a robot cleaner;

receiving the signal transmitted from the robot cleaner by the station via a receiving unit;

determining whether a Doppler shift is observed by the receiving unit; and

detecting a direction in which the robot cleaner is positioned and a distance from the robot cleaner based on the Doppler shift.

32. The control method of a robot cleaner system according to claim 31, wherein the receiving unit comprises an antenna to receive the signal transmitted from the robot cleaner.

33. The control method of a robot cleaner system according to claim 32, wherein the receiving unit further comprises a rotation body provided to rotate in the station and in which the antenna is installed, and

movement of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

34. The control method of a robot cleaner system according to claim 31, wherein the direction detector determines a direction indicated by the antenna when the Doppler shift is not observed from the frequency of the signal received by the receiving unit as the direction in which the robot cleaner is positioned.

35. The control method of a robot cleaner system according to claim 32, wherein, when the Doppler shift is observed as the antenna moves along a rotation track of the rotation body, an angle θ

₁ between a direction indicated by the antenna and a direction in which the robot cleaner is positioned is expressed by the following formula,

36. The control method of a robot cleaner system according to claim 32, wherein a distance R from a central point of the receiving unit to a transmitter of the robot cleaner is expressed by the following formula,

37. A robot cleaner system comprising:

at least three transmitters to transmit signals of predetermined natural frequencies different from each other; and

a station comprising a movable receiving unit to receive the signals transmitted from the at least three transmitters, to observe the Doppler shifts of the received signals, and for to obtain direction information of the respective at least three transmitters based on the Doppler shifts observed by the receiving unit and relative present positions of the station based on the direction information of the at least three transmitters.

38. The robot cleaner system according to claim 37, wherein the receiving unit comprises an antenna to receive the signals transmitted from the at least three transmitters.

39. The robot cleaner system according to claim 38, wherein the receiving unit further comprises a rotation body provided to rotate in the robot cleaner and in which the antenna is installed, and

rotation of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

40. The robot cleaner system according to claim 38, wherein the receiving unit further comprises:

a frequency detector to detect the frequencies of the signals received by the receiving unit; and

a direction detector to detect directions in which the at least three transmitters are positioned by comparing the frequencies detected by the frequency detector and the frequencies of the signals transmitted from the station and to generate direction information.

41. The robot cleaner system according to claim 40, wherein the direction detector determines directions indicated by the antenna when the Doppler shifts are not observed from the frequencies detected by the frequency detector as the directions in which the at least three transmitters are positioned.

42. The robot cleaner system according to claim 38, wherein, when the Doppler shift is observed as the antenna moves along one of a rotation track of the robot cleaner and a rotation track of the rotation body, an angle θ

₁ between a forward direction of the robot cleaner and directions in which the at least three transmitters are positioned is expressed by the following formula,

43. The robot cleaner system according to claim 38, wherein the at least three transmitters comprise a first transmitter, a second transmitter, and a third transmitter, and

a present position of the robot cleaner is detected by estimating a first angle formed by the first transmitter, the robot cleaner, and the second transmitter, and a second angle formed by the second transmitter, the robot cleaner, and the third transmitter and taking the first angle and the second angle into consideration.

44. The robot cleaner system according to claim 38, wherein a plurality of antennas are installed at uniform intervals.

45. The robot cleaner system according to claim 37, wherein one of the at least three transmitters comprises a docking station to charge the robot cleaner and discharge foreign substances.

46. The robot cleaner system according to claim 37, wherein the at least three transmitters are installed at predetermined fixed positions.

47. A control method of a robot cleaner system comprising:

transmitting signals of predetermined natural frequencies from at least three transmitters;

receiving the signals transmitted from the at least three transmitters by a robot cleaner via a receiving unit;

determining whether a Doppler shift is observed by the receiving unit; and

detecting directions in which the at least three transmitters are positioned based on the observation of the Doppler shift.

48. The control method of a robot cleaner system according to claim 47, wherein the receiving unit comprises an antenna to receive the signals transmitted from the at least three transmitters.

49. The control method of a robot cleaner system according to claim 48, wherein the receiving unit further comprises a rotation body provided to rotate in the robot cleaner and in which the antenna is installed, and

rotation of the receiving unit is movement of the antenna of the receiving unit along a rotation track of the rotation body due to the rotation of the rotation body.

50. The control method of a robot cleaner system according to claim 48, wherein the direction detector determines directions indicated by the antenna when the Doppler shifts are not observed from the frequencies detected by the frequency detector as the directions in which the at least three transmitters are positioned.

51. The control method of a robot cleaner system according to claim 48, wherein, when the Doppler shift is observed as the antenna moves along one of a rotation track of the robot cleaner and a rotation track of the rotation body, an angle θ

₁ between a forward direction of the robot cleaner and directions in which the at least three transmitters are positioned is expressed by the following formula,

52. The control method of a robot cleaner system according to claim 48, wherein the at least three transmitters comprise a first transmitter, a second transmitter, and a third transmitter, and

a present position of the robot cleaner is detected by estimating a first angle formed by the first transmitter, the robot cleaner, and the second transmitter, and a second angle formed by the second transmitter, the robot cleaner, and the third transmitter and taking the first angle and the second angle into consideration.