Mobile robot control system

• US 5,652,489 A
• Filed: 08/24/1995
• Issued: 07/29/1997
• Est. Priority Date: 08/26/1994
• Status: Expired due to Term

• Current Assignee: Moneual Incorporated (Hong-Seok Park, MBA)
• Original Assignee: Minolta Co., Ltd. (Konica Minolta Inc.)
• Inventors: Kawakami, Yuichi
• Primary Examiner(s): IP, SHIK LUEN PAUL
• Application Number:
  US08/518,819
• Time in Patent Office: 705 Days
• Field of Search: 318/560-686, 901/1, 901/3, 901/5, 901/7, 901/15-23, 364/424.02-424.06, 395/905, 395/913, 180/168-169
• US Class Current: 318/587
• 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 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30
• CPC Class Codes: G05D 1/0289 with means for avoiding collisions between vehicles vehicle fittings for automatically controlling speed including means for detecting potential obstacles B60K31/0008; avoiding obstacles by action on the steering system B62D; radar, sonar, lidar systems designed for anti-collision purposes G01S13/93, G01S15/93, G01S17/93

Abstract

A mobile robot control system with plural mobile robots each of which moves along a predetermined route in the same area. One mobile robot gives way to the other mobile robot when the mobile robot receives a signal emitted by the other mobile robot. A mobile robot moving on a predetermined route has a sensor which senses whether or not an obstacle exists on the route. The sensor senses again after a predetermined time from the first sensing whether the sensor still detects the obstacle existing on the route at the first sensing.

Claims

1. A mobile robot moving on a predetermined route, comprising:

a propulsion device;

a sensor which senses whether or not an obstacle exists on the route; and

a controller which controls the propulsion device to stop moving the mobile robot when the sensor detects the obstacle, and which controls the sensor to sense again after predetermined time from the first sensing whether the sensor still detects the obstacle existing on the route at the first sensing.

2. A mobile robot as claimed in claim 1, wherein the controller further controls the propulsion device to change direction of movement of the robot in order to avoid a collision with the obstacle when the sensor detects the obstacle again at the second sensing.

3. A mobile robot as claimed in claim 1, wherein the controller controls the propulsion device to start moving the robot when the sensor detects that no obstacle exists on the route at the second sensing.

4. A mobile robot control system with plural mobile robots comprising:

first and second mobile robots each of which moves along a predetermined route in a common area;

a first signal emitter on said first mobile robot which emits a signal representing a position of said first mobile robot;

a second signal emitter on said second mobile robot which emits a signal representing a position of said second mobile robot;

a first signal receiver on said first mobile robot which receives a signal emitted by said second signal emitter;

a second signal receiver on said second mobile robot which receives a signal emitted by said first signal emitter; and

a controller which controls the second mobile robot to give way to the first mobile robot when said second signal receiver receives the signal emitted by said first signal emitter wherein, if said second signal receiver receives the signal from said first signal emitter during an emitting period of said second signal emitter, said second signal emitter stops emitting for a predetermined time.

5. A mobile robot control system as claimed in claim 4, wherein said second signal emitter emits its signal again after the predetermined time if no signal is received by said second signal receiver during the predetermined time.

6. A mobile robot control system as claimed in claim 4, wherein the controller controls the mobile robot to give way to the first mobile robot when the signal receiver of the second mobile robot receives the signal from said first signal emitter while the signal emitter of the second mobile robot emits no signal.

7. A mobile robot control system as claimed in claim 4, wherein the predetermined time for one mobile robot is different from that for another mobile robot.

8. A mobile robot control system as claimed in claim 4, wherein the predetermined time is randomly determined.

9. A mobile robot control system as claimed in claim 4, wherein the controller controls the second mobile robot to stop moving during the predetermined time.

10. A mobile robot control system as claimed in claim 4, wherein each mobile robot has a sensor which senses whether or not an obstacle exists on the route, and wherein the signal emitter emits its signal in response to sensing that an obstacle exists on the route.

11. A mobile robot control system as claimed in claim 10, wherein each signal emitter delays the emission of its signal for a period of time after sensing that an obstacle exists on the route, and wherein the delay period for one mobile robot is different from that for the other mobile robot.

12. A mobile robot control system as claimed in claim 11, wherein the delay period for each mobile robot for emitting the signal after detecting the obstacle on the route is randomly determined.

13. A mobile robot moving on a predetermined route, comprising:

a propulsion device;

a sensor which senses whether or not an obstacle exists on the route; and

a controller which controls the propulsion device to decrease the speed of the robot when the sensor detects the obstacle, and which controls the sensor to sense again after a predetermined time from the first sensing whether the sensor still detects the obstacle existing on the route at the first sensing.

14. A mobile robot as claimed in claim 13, wherein the controller controls the propulsion device to increase the speed of the robot when the sensor detects that no obstacle exists on the route at the second sensing.