Autonomous running control system for vehicle and the method there

• US 5,938,704 A
• Filed: 10/24/1996
• Issued: 08/17/1999
• Est. Priority Date: 11/07/1995
• 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:
  US08/740,075
• Time in Patent Office: 1,027 Days
• Field of Search: 701/23, 701/25, 701/213, 701/215, 701/216, 180/167, 180/168, 342/357, 342/457, 318/587
• 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: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0265 using buried wires
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS

Abstract

An autonomous running control system capable of guiding a lawn-mowing work vehicle to a target point unmanned with high accuracy. Normally, the vehicle runs autonomously according to the D-GPS/dead reckoning navigation method. When the vehicle runs in an area where obstacles and ups-and-downs exists, the running control is switched to a magnetic guidance and the vehicle moves along the magnetic rail underground. When the vehicle comes into a normal operation again, the running control is shifted to the G-GPS/dead reckoning navigation method again. Further, when the vehicle comes near a target points, the running control is switched to the dead reckoning navigation method capable of guiding the vehicle accurately to the target point. When the vehicle arrives at the work area, it conducts a lawn mowing work according to the trace running control, finding the boundary between mowed and unmowed areas. Thus, the autonomous running control system can make an accurate guidance under any geographical conditions by means of selectively changing the running control method according to terrains and works.

Claims

1. An autonomous running control system of a vehicle for autonomously guiding said vehicle, the system comprising:

first positioning means for identifying a first position of said vehicle based on a positioning information from satellites and a correction information with respect to said positioning information,

second positioning means for identifying a second position of said vehicle based on a running history from a reference point,

third positioning means for detecting an existence of a magnetic rail through outputs of a plurality of magnetic sensors of said vehicle and for identifying a third position of said vehicle on said magnetic rail;

correction means for correcting said second position with said first position and for producing a corrected position of said vehicle;

first running control means for guiding said vehicle autonomously based on said corrected position;

second running control means for guiding said vehicle autonomously based on said second position;

third running control means for guiding said vehicle autonomously along said magnetic rail based on said third position; and

running control switching means for selecting a running control means from among said first running control means, said second running control means and said third running control means.

2. The autonomous running control system according to claim 1, wherein

said second running control means is selected when a traveling distance of said vehicle from the present position to a next target point is smaller than a predetermined value and said first running control means is selected when said traveling distance is larger than said predetermined value.

3. The autonomous running control system according to claim 1, wherein

said third positioning means recognizes said vehicle being on said magnetic rail when a difference between a maximum value and an average value of outputs of said magnetic sensors is larger than a predetermined value, and defines said third position based on positions of a magnetic sensor showing said maximum value of output and said magnetic sensors disposed adjacent said magnetic sensor showing said maximum value of output.

4. An autonomous running control method of a vehicle for guiding said vehicle autonomously, comprising

identifying a first position of said vehicle based on a positioning information from satellites and a correction information with respect to said positioning information;

identifying a second position of said vehicle based on a running history from a reference point;

detecting an existence of a magnetic rail through outputs of a plurality of magnetic sensors of said vehicle for identifying a third position of said vehicle on said magnetic rail;

correcting said second position with said first position and producing a corrected position of said vehicle; and

selecting a running control method from any one of guiding said vehicle based on said corrected position, guiding said vehicle based on said second position and guiding said vehicle based on said third position.

5. An autonomous running control system of a vehicle for autonomously running said vehicle, the system comprising;

vehicle position detecting means for identifying a position of said vehicle based on at least one of GPS information and running history;

first running control means for running said vehicle autonomously based on said identified position;

magnetic rail detecting means for detecting an existence of a magnetic rail;

second running control means for guiding said vehicle autonomously along said detected magnetic rail; and

running control switching means for switching a control mode between said first running controls means and said second running control means according to whether a magnetic rail is detected by said magnetic rail detecting means.