Obstacle data processing system for unmanned vehicle

• US 4,809,178 A
• Filed: 05/20/1987
• Issued: 02/28/1989
• Est. Priority Date: 05/22/1986
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation)
• Original Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation)
• Inventors: Hongo, Takero, Watanabe, Keiichi, Ninomiya, Yoshiki, Arakawa, Hideo, Sugimoto, Gunji
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US07/051,831
• Time in Patent Office: 650 Days
• Field of Search: 364/424, 364/443, 364/460, 364/461, 318/580, 318/587, 180/167, 180/168, 180/169, 901/1, 901/49, 367/909
• US Class Current: 701/200
• 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

Abstract

An obstacle data processing system for an unmanned self-controlled vehicle, capable of enabling the vehicle to automatically avert any obstacle which lies in the course of running of the vehicle. The system has obstacle position memory device capable of accumulating position data concerning specific obstacles and, hence, forming data concerning the distribution of the obstacles. The vehicle therefore can conduct appropriate averting operation in accordance with the distribution of a plurality of obstacles.

Claims

1. An obstacle data processing system for self-controlled unmanned vehicle having a position and heading measuring means for measuring the position and heading of said unmanned vehicle and a running course memory means for storing position data of the position of said vehicle along a course so as to enable said vehicle to run along said course, said system comprising:

obstacle detecting means for detecting an obstacle and for outputting position data of the position of said obstacle in terms of coordinate values on a coordinate system fixed to said vehicle;

absolute position computing means for converting, in accordance with the position and heading measured by said position and heading measuring means at the time when said obstacle is detected, said position data derived from said obstacle detecting means into absolute position data in terms of coordinate values on an absolute coordinate system which is set to the ground where said vehicle runs and which constitutes a reference for the control of running of said vehicle;

obstacle position memory means for storing the position data of specific obstacles which have been detected, whose coordinate values are converted into the absolute coordinate values, said absolute coordinate values being stored and outputted;

comparison means for comparing position of an obstacle which has been converted by said position computing means with the positions of said specific obstacles the position data which have been stored in said obstacle memory means; and

storage obstacle position position computing means for judging, in accordance with the result of the comparison performed by said comparison means, the position data of a specific obstacle to be stored in said obstacle position memory means and for outputting this position data, on the basis of the position data of the specific obstacles stored in said obstacle position memory means or the obstacle position data converted by said absolute position computing means.

2. An obstacle data processing system for a self-controlled unmanned vehicle according to claim 1, wherein said comparison means compares with a predetermined threshold value, the distances between the coordinate values of specific obstacles stored in said obstacle position memory means and the coordinate value of position of an obstacle after conversion by said absolute position computing means, said comparison means judging, when all said distances are greater than said threshold value, that said obstacle is a newly detected obstacle, whereas, when at least one of said distances is exceeded by said threshold value, said comparison means judges that said obstacle is identical to one of said specific obstacles which has been already detected and the position coordinate value of which has been already stored in said obstacle position memory means.

3. An obstacle data processing system for a self-controlled unmanned vehicle according to claim 2, wherein said storage obstacle position computing means outputs the position coordinate value of said obstacle converted by said absolute position computing means as position data of a specific obstacle, when said comparison means has judged that said obstacle is a newly detected one, whereas, when said comparison means has judged that said obstacle is identical to one of said specific obstacles which has been already detected and the position coordinate value of which has been already stored in said obstacle position memory means, said storage obstacle position computing means does not output the position coordinate value of said obstacle converted by said absolute position computing means as position data of a specific obstacle.

4. An obstacle data processing system for a self-controlled unmanned vehicle according to claim 2, wherein, when said comparison means has judged that said obstacle is identical to one of said specific obstacles which have been already detected and the position coordinate values of which has been already stored in said obstacle position memory means, said storage obstacle position computing means corrects the position coordinate value of said one of said specific obstacles in accordance with the position coordinate value of the newly detected obstacle, and outputs the corrected coordinate value as the position data of a specific obstacle

5. An obstacle data processing system for a self-controlled unmanned vehicle according to claim 1, further comprising:

obstacle criticalness judging means for determining, when the position data of the specific obstacle to be stored is output from said storage obstacle position computing means, the distance between said position data of said specific obstacle and the position data along said course stored in said running course memory means and for comparing the determined distance with a predetermined threshold value which is used as the basis for judgement of the closeness of said obstacle to said course, said obstacle criticalness judging means being adapted for deciding, when said distance is smaller than said threshold value, that said obstacle should be averted, whereas, when said distance is greater than said threshold value, said obstacle criticalness judging means judges that there is no need for said vehicle to conduct any averting operation; and

limiting means for limiting the storage of the obstacle position data in said obstacle position memory means when said obstacle criticalness judging means has judged that there is no need for said vehicle to conduct any operation to avert said obstacle.

6. An obstacle data processing system for a self-controlled unmanned vehicle according to claim 1, further comprising:

obstacle detecting region computing means for outputting, in terms of the coordinate values on said absolute coordinate system, an obstacle detecting region in which any object is detectable from the instant position and heading of said vehicle, on the basis of the instant position and heading of said vehicle as measured by said position and heading measuring means and also on the basis of a predetermined coverage of said obstacle detecting means and the position of mounting of said obstacle detecting means on said vehicle;

obstacle movement detecting means for judging whether any one of the specific obstacles the position data of which have been stored in said obstacle position memory means resides in the present obstacle detecting region which is output from the obstacle detecting region computing means, said obstacle movement detecting means being further adapted for judging, upon judging that any one of said specific obstacles resides in said obstacle detecting region and in accordance with the new data which is output from said obstacle movement detecting means and representing the presence or absence of any obstacle and, when said obstacle exists, the position data of said obstacle is converted into values on said absolute coordinate system by said absolute position computing means, whether said any one of the specific obstacles which is to be detected in said obstacle detecting region has moved out of said obstacle detecting region and, hence, not detected; and

stored obstacle position erasing means for erasing the position data of said obstacle stored in said obstacle position memory means when said obstacle movement detecting means has judged that said obstacle has been moved out of said obstacle detecting region;

whereby the position data of positions of obstacles stored in said obstacle position memory means is corrected in accordance with the movement of said obstacle.

7. An obstacle data processing system for a self-controlled unmanned vehicle having a position and heading measuring means for measuring the position and heading of said unmanned vehicle and a running course memory means for storing position data of the position of said vehicle along a course so as to enable said vehicle to run along said course, said system comprising:

obstacle detecting means for detecting an obstacle and for outputting position data of the position of said obstacle in terms of coordinate values on a coordinate system fixed to said vehicle;

absolute position computing means for converting, in accordance with the position and heading measured by said position and heading measuring means at the time when said obstacle is detected, said position data derived from said obstacle detecting means into absolute position data in terms of coordinate values on an absolute coordinate system based on the position of said vehicle and which constitutes a reference for the control of running of said vehicle;

obstacle position memory means for storing the position data of specific obstacles which have been detected and converted into said absolute coordinate system.

8. An obstacle data processing system for a self-controlled unmanned vehicle, having position and heading measuring means for measuring the position and heading of said unmanned vehicle and for outputting position and heading data corresponding to the detected position and heading, running course memory means for storing data concerning a running course which determines the movement of said unmanned vehicle, driving means for driving and steering said unmanned vehicle, and running control means for comparing said position and heading data with said data of said course stored in said running course memory means and for computing the controlled variable for controlling said driving means, thus enabling said unmanned vehicle to run along said course in a self-controlled manner, said system comprising:

obstacle detecting system for detecting the positions of obstacles and for outputting the obstacle position data including

obstacle detecting means for detecting an obstacle and for outputting position data of the position of said obstacle in terms of coordinate values on a coordinate system fixed to said vehicle;

absolute position computing means for converting, in accordance with the position and heading measured by said position and heading measuring means at the time when said obstacle is detected, said position data derived from said obstacle detecting means into absolute position data in terms of coordinate values on an absolute coordinate system based on the position of said vehicle and which constitutes a reference for the control of running of said vehicle;

obstacle position memory means for storing the position data of specific obstacles which have been detected and converted into said absolute coordinate system;

obstacle criticalness judging means for computing, on the basis of the data of said course stored in said running course memory means and the obstacle position data derived from said obstacle detecting means, the distance between an obstacle and said running course, said obstacle criticalness judging means being further adapted to judge whether it is necessary for said unmanned vehicle to conduct any averting operation, through comparison between the computed distance and a threshold value; and

averting operation determining means for determining, when said obstacle criticalness judging means has judged that an averting operation is necessary, an averting operation which will enable said unmanned vehicle to detour the point where said obstacle exists, in accordance with said obstacle position data derived from said obstacle detecting means and said position and heading data obtained from said position and heading measuring means, while taking into account the distance between said obstacle and the position at which said vehicle will commence said averting operation, said averting operation determining means being further adapted for renewing the data of said running course stored in said running course memory means in accordance with said averting operation determined by said averting operation determining means, thereby enabling said unmanned vehicle to execute said averting operation.