Travel control method, travel control device, and mobile robot for mobile robot systems

• US 5,568,030 A
• Filed: 06/07/1995
• Issued: 10/22/1996
• Est. Priority Date: 04/25/1989
• Status: Expired due to Fees

• Current Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited)
• Original Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited)
• Inventors: Nishikawa, Yuji, Onishi, Masanori
• Primary Examiner(s): IP, SHIK LUEN PAUL
• Application Number:
  US08/480,303
• Time in Patent Office: 503 Days
• Field of Search: 318/560-640, 901/1, 901/3, 901/5, 901/7, 901/13, 901/23, 395/901, 395/904, 395/705, 395/913, 395/80-99, 364/424.02, 364/424.04
• US Class Current: 318/587
• CPC Class Codes: G05B 2219/31003 Supervise route, reserve route and allocate route to vehicle, avoid collision
• 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 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: G05D 1/0263 using magnetic strips
• 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 1/0297 by controlling means in a control room
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

In the travel control method in the mobile robot system including a plurality of mobile robots and the control station for controlling these mobile robot, the control station directs one of a plurality of mobile robots to the destination robot, responding to the direction, searches the route to the destination directed by the control station and sends the result to the control station. The control station which receives this in formation checks if the travel path searched by the mobile robot is already reserved by other mobile robots or not by the reservation table. If not, the control station informs the reserve completion to said mobile robot. The mobile robot which received the information of the reservation completion travels automatically along the travel path which is already reserved. In addition, said control station, when there are other mobile robots which disturb the travel of each mobile robot, directs the robot to wait or to take an alternate route according to the situation, or directs other mobile robots that disturb the travel to halt.

Claims

1. A travel control method for a mobile robot system comprising a plurality of mobile robots, a control station for controlling said mobile robots and radio communication apparatus for communicating between each of said mobile robots and said control station, each of said mobile robots having a map memory for storing travel map information, means for determining a best travel route to a destination based on said travel map information, and at least one sensor mounted on each of said robots for detecting said best travel route, said travel control method comprising the steps of:

designating by means of said control station a destination for each of said mobile robots;

communicating said determinations to said mobile robots via said radio communication apparatus;

determining within each of said mobile robots said best travel route based on said travel map information read out from said map memory when said designation has been designated by said control station;

transmitting from each of said mobile robots to said control station a request to reserve each position on said best travel route determined by said mobile robot;

reserving in said control station said best travel route for each of said mobile robots based on said reservation request from each of said mobile robots;

moving each of said mobile robots automatically along said reserved best travel route, each of said mobile by the at least one sensor;

storing data indicative of the travel configuration of said mobile robot and data indicative of unidirectional travel, said travel configuration including transverse movement and forward and backward movement; and

controlling the travel of the mobile robot according to the contents of said travel state memory.

2. A travel control method for a mobile robot system comprising a plurality of mobile robots, a control station for controlling said mobile robots and radio communication apparatus for communicating between each of said mobile robots and said control station, each of said mobile robots having a map memory for storing travel map information, means for determining a best travel route to a destination based on said travel map information, and at least one sensor mounted on each of said robots for detecting said best travel route, said travel control method comprising the steps of:

designating by means of said control station a destination for each of said mobile robots;

communicating said determinations to said mobile robots via said radio communication apparatus;

determining within each of said mobile robots said best travel route based on said travel map information read out from said map memory when said designation has been designated by said control station;

transmitting from each of said mobile robots to said control station a request to reserve each position on said best travel route determined by said mobile robot;

reserving in said control station said best travel route for each of said mobile robots based on said reservation request from each of said mobile robots; and

moving each of said mobile robots automatically along said reserved best travel route, each of said mobile by the at least one sensor;

wherein said map information includes travel offset data indicative of a travel offset value from a travel datum for every travel element path and for every travel direction, wherein travel of said robot is controlled according to said offset data, said travel offset data being indicative of a right side pass, a left side pass, a right end pass and a left end pass, and wherein said mobile robot sensor also detects and measures distances to objects along the best travel route.

3. A travel control system for controlling the motion of a plurality of mobile robots, said system comprising:

a control station including;

a) means for indicating a destination of each mobile robot;

b) means for reserving a travel route for each mobile robot;

c) means for transmitting to each mobile robot the travel routes of the other mobile robots, position data indicative of the present position of other mobile robots and condition data indicative of the present condition of other mobile robots;

d) a collision table storing the positions of nodes a which a collision a collision between mobile robots may occur; and

e) approach prohibition means for receiving travel route information from said mobile robots, reaching nodes stored in said collision table corresponding to the same travel route, and prohibiting the approach of other said mobile robots to said node;

and in which each mobile robot comprises;

a) means for searching for the route indicated by the control station and sending information indicative of the route to the control station;

b) automatic travel means for traveling automatically along the found travel route;

c) travel data information means for informing the control station of position data indicating the present position of the mobile robot along the travel route and condition data indicating the present condition of the mobile robot;

d) travel data memory means for writing the travel route of other mobile robots, position data indicating the position of other mobile robots and condition data indicating the present condition of other mobile robots;

e) a travel state memory for storing data indicative of the travel configuration of said mobile robot and data indicative of unidirectional travel, said travel configuration including transverse movement and forward and backward movement; and

f) means for controlling the travel of the mobile robot according to the contents of said travel state memory.

4. A travel control system for controlling the motion of a plurality of mobile robots, said system comprising:

a control station including;

a) means for indicating a destination of each mobile robot;

b) means for reserving a travel route for each mobile robot;

c) means for transmitting to each mobile robot the travel routes of the other mobile robots, position data indicative of the present position of other mobile robots and condition data indicative of the present condition of other mobile robots;

d) a collision table storing the positions of nodes a which a collision a collision between mobile robots may occur; and

e) approach prohibition means for receiving travel route information from said mobile robots, reaching nodes stored in said collision table corresponding to the same travel route, and prohibiting the approach of other said mobile robots to said node;

and in which each mobile robot comprises;

a) means for searching for the route indicated by the control station and sending information indicative of the route to the control station;

b) automatic travel means for traveling automatically along the found travel route;

c) travel data information means for informing the control station of position data indicating the present position of the mobile robot along the travel route and condition data indicating the present condition of the mobile robot; and

d) travel data memory means for writing the travel route of other mobile robots, position data indicating the position of other mobile robots and condition data indicating the present condition of other mobile robots;

wherein said map information includes travel offset data indicative of a travel offset value from a travel datum for every travel element path and for every travel direction, and wherein said robot further comprises a travel control section for controlling travel according to said offset data, said travel offset data being indicative of a right side pass, a left side pass, a right end pass and a left end pass, said mobile robot further having a sensor for detecting and measuring distances to objects along the travel route.