Autonomous running control system for vehicle and the method thereof

• US 5,563,786 A
• Filed: 02/02/1995
• Issued: 10/08/1996
• Est. Priority Date: 02/16/1994
• Status: Expired due to Fees

• Current Assignee: Fuji Heavy Industries Limited (Subaru Corp.)
• Original Assignee: Fuji Heavy Industries Limited (Subaru Corp.)
• Inventors: Torii, Tsuyoshi
• Primary Examiner(s): ZANELLI, MICHAEL J
• Application Number:
  US08/383,082
• Time in Patent Office: 614 Days
• Field of Search: 364/424.02, 364/449, 364/450, 180/167, 180/168, 342/357, 342/457, 318/587, 318/581
• US Class Current: 701/23
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial
• CPC Class Codes: G01S 5/0009 Transmission of position information to remote stations involving assistance data G01S5/0236
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS

Abstract

The position of the vehicle is detected by the position information from satellites and by the correction information based on the position data of a known point. On the other hand, the position of the vehicle is found based on the running histories since the reference point. Next, the difference between the position data from satellites and the position data based on the running histories at each moment when the position data is received from satellites is calculated and those differences are averaged to obtain a correction value. Finally the current position of the vehicle is calculated by correcting the position data based on the running histories by the newest correction value. Consequently, in the autonomous running control system an accurate position of the vehicle can be found without stopping the vehicle, even when the position data from satellites does not have a sufficient accuracy. Thus, according to the present invention an efficient and accurate autonomous running can be achieved.

Claims

1. An autonomous running control system for controlling a vehicle so as to run said vehicle autonomously, comprising:

a stationary station for receiving radio waves from a plurality of satellites at a stationary point where a position is known and for finding a position at said stationary point based on said radio waves;

differential information calculating means for calculating a difference between said position at said stationary point based on said radio waves and said known position in said stationary station and outputting said difference as a difference information;

differential information transmitting means for transmitting said difference information from said stationary station to said system of said vehicle;

first position finding means for receiving said radio waves from said plurality of satellites and for finding a first position at a point where said vehicle is running;

differential information receiving means for receiving said difference information from said stationary station;

first corrected position finding means for finding a corrected first position at said point where said vehicle is running based on said first position and said said differential information;

running history detecting means for detecting a running history of said vehicle;

second position finding means for finding a second position at said point where said vehicle is running based on said running history at the moment when said radio waves are received from said satellites;

differential values calculating means for calculating a differential value between said corrected first position and said second position at each moment when said radio waves are received from said satellites;

correction value calculating means for producing a correction value by averaging a predetermined number of said differential values; and

final position finding means for finding a final position where said vehicle is currently located by correcting said second position with said correction value.

2. The system according to claim 1, wherein

said running history detecting means comprise a running distance detecting device, a geomagnetic sensor and a position calculating device for calculating a position.

3. The system according to claim 1, wherein

said running history detecting means comprise a running distance detecting device, a gyro compass and a position calculating device for calculating a position.

4. An autonomous running control method for controlling a vehicle so as to run said vehicle autonomously, the method comprising the steps of:

receiving radio waves from a plurality of satellites at a stationary point where a position is known and for finding a position at said stationary point based on said radio waves;

calculating a difference between said position at said stationary point based on said radio waves and said known position and outputting said difference as a difference information;

transmitting said difference information;

receiving said radio waves from said plurality of satellites and finding a first position at a point where said vehicle is running;

receiving said difference information;

finding a corrected first position at said point where said vehicle is running based on said first position and said differential information;

detecting a running history of said vehicle;

finding a second position at said point where said vehicle is running based on said running history at the moment when said radio waves are received from said satellites;

calculating a differential value between said corrected first position and said second position at each moment when said radio waves are received from said satellites;

producing a correction value by averaging a predetermined number of said differential values; and

finding a final position where said vehicle is currently located by way of correcting said second position with said correction value.