System for automatically controlling movement of unmanned vehicle and method therefor

• US 4,716,530 A
• Filed: 02/22/1985
• Issued: 12/29/1987
• Est. Priority Date: 05/21/1984
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Meidensha
• Original Assignee: Kabushiki Kaisha Meidensha
• Inventors: Yoshida, Susumu, Ogawa, Hiroshi, Miyazaki, Yasuyuki, Sasaki, Shinichi
• Primary Examiner(s): Chin, Gary
• Application Number:
  US06/704,522
• Time in Patent Office: 1,040 Days
• Field of Search: 364/424, 364/443, 364/449, 364/431.04, 180/167, 180/168, 180/169, 318/587, 340/52 F
• US Class Current: 701/23
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0265 using buried wires

Abstract

A system for automatically controlling movement of an unmanned vehicle and method therefor wherein one or more than one marker is installed between each branched corner formed by a guide road through which the vehicle passes for providing an indicating means for the vehicle to accelerate, decelerate, or turn the branched corner and the vehicle includes detecting means for detecting the presence of the marker and outputting a signal indicating that the marker is located at the corresponding position and a controller in which data and main program on a pattern of turning the movement of the vehicle at any given branched corner and vehicle speed control according to the detected number of markers in accordance with a route of movement from a starting point which is loaded prior to the start of the vehicle so that the control for turning the movement direction of the vehicle and vehicle speed is carried out by fetching the corresponding above-described data and main program of the pattern according to the number of detected markers. Furthermore, at least one timer is provided in the controller which outputs an interrupt signal so that an interrupt program is executed for controlling an on-and-off period of steering and/or movement motor chopper circuit with the main program being temporarily halted.

Claims

1. A system for automatically controlling movement of an unmanned vehicle, comprising:

(a) first means having at least one curved corner defining at least one predetermined route from a starting point to a final destination of the vehicle so as to guide the vehicle to move therealong, the first means including (a) a guide wire extended on the ground along the predetermined route of movement, (b) a generator for generating an alternating current magnetic field around the guide wire, and (c) a detector installed on the vehicle for detecting the magnetic field around the guide wire and outputting a signal indicating the intensity of the magnetic field;

(b) second means, disposed near the first means along the predetermined route, for indicating one of various movement control modes to be carried out by the vehicle, the second means including a plurality of markers, each marker located on at least one side of said guide wire adjacent to the curved corner and each marker generating a signal;

(c) third means, installed on the vehicle, for detecting the presence of said second means as the vehicle moves; and

(d) fourth means, installed on the vehicle and having predetermined data on the various control modes of movement of the vehicle to be carried out sequentially during movement of the vehicle along the predetermined route when said second means is detected by said third means for controlling the movement of the vehicle along the predetermined route, the fourth means controlling the movement of the vehicle in any one of the various control modes and controlling the movement direction of the vehicle according to the total detected number of said markers so as to move the vehicle along the guide wire in accordance with the signal from the detector.

2. The system according to claim 1, wherein said markers are located at both sides along said guide wire in equal numbers and at symmetrical positions across said guide wire adjacent to said curved corner.

3. The system according to claim 1, wherein said fourth means comprises fifth means for controlling the vehicle speed in accordance with a first duty ratio of a signal derived from a controller calculated from said predetermined data, sixth means for controlling the movement direction in accordance with a second duty ratio of another signal derived from the controller calculated from said predetermined data, and the controller having a memory in a predetermined memory area of which stores said predetermined data, for calculating said first and second duty ratios according to the predetermined data and sending a signal to each of said fifth and sixth means in accordance with the calculated duty ratio.

4. The system according to claim 3, wherein said fifth means comprises a first reversible motor linked with a drive wheel of the vehicle which drives said drive wheel to move in accordance with an average current flowing therethrough and a first chopper circuit having a first chopping transistor which supplies the average current for said first motor in accordance with said first duty ratio and said sixth means comprises a second reversible motor linked with a steering wheel of the vehicle which rotates said steering wheel to turn the movement direction in accordance with an average current flowing therethrough and a second chopper circuit having at least one second chopping transistor which supplies the average current for said second motor in accordance with said second duty ratio.

5. The system according to claim 4, wherein said controller executes an interrupt processing for determining an on-and-off period of each of said first and second chopping transistors and includes two timers each for the corresponding chopping transistor, the operation duration of which is dependent on the determined on-and-off period.

6. The system according to claim 1, wherein said second means comprises two markers one located at the starting point for generating a signal so that said fourth means controls movement of the vehicle such that the vehicle starts and is accelerated and the other located at the final arrival point for generating a signal so that said fourth means controls movement of the vehicle such that the vehicle is decelerated and stops at the final arrival point.

7. The system according to claim 1, wherein said second means comprises a plurality of markers each located at equal interval of distance along said guide wire and for generating a signal so that said fourth means controls movement of the vehicle according to the total detected number of said markers.

8. The system according to claim 1, wherein said second means comprises at least one marker which comprises a light emitting element and said third means comprises a light sensing element for receiving a light from said light emitting element and outputting an electrical signal indicative thereof.

9. A system for automatically controlling movement of an unmanned vehicle, comprising:

(a) a plurality of stations at which the vehicle starts or stops;

(b) guide means connected between each of said stations for guiding the vehicle to move therealong, said guide means having at least one branched corner located so that the vehicle turns in accordance with a predetermined route of movement from one of said stations at which the vehicle starts to one of said stations at which the vehicle stops;

(c) a plurality of markers installed aside said guide means for indicating any one of various control modes of movement of the vehicle to be carried out when the vehicle moves along the predetermined route of movement;

(d) a marker sensor installed on the vehicle for detecting the presence of said markers during movement of the vehicle; and

(e) a controller installed on the vehicle for storing predetermined data on the various control modes of movement of the vehicle to be carried out sequentially during movement of the vehicle along the predetermined route and for controlling movement of the vehicle in any one of the various control modes according to the total detected number of said markers.

10. The system according to claim 9, wherein one of said markers is located in front of said branched corner for indicating a control mode such that the vehicle speed is maintained at a constant speed.

11. The system according to claim 9, wherein two of said markers are located at both of said stations at which the vehicle is started and is stopped for indicating control modes such that the vehicle speed is increased and the vehicle is stopped, respectively.

12. The system according to claim 9, wherein three of said markers are located adjacent to said branched corner, a first one of said three markers being located in front of said branched corner for indicating one of the various control modes such that the vehicle is decelerated, a second one of said three markers being located in front of said branched corner followed by said first marker for indicating one of the various control modes such that the vehicle is turned at the branched corner, and a third one of said three markers being located at a position near the branched corner for indicating one of the various control modes such that the vehicle passed through the branched corner is accelerated.

13. The system according to claim 9, wherein said plurality of markers located at equal intervals to each other so that the vehicle controller controls movement of the vehicle according to the total detected number of said markers whenever the vehicle passes through each marker.

14. The system according to claim 9, wherein said controller comprises a microcomputer having the predetermined data and connected to said marker sensor, a first chopper circuit for controlling a current flow through a first motor whose driving torque determines a vehicle speed dependent upon a first duty ratio of a first predetermined period of a first on-and-off signal derived from said predetermined data and a second chopper circuit for controlling a current flow through a second motor whose driving torque and current flow direction determine a steering angle dependent upon a second duty ratio of a second predetermined period of a second on-and-off signal derived from said predetermined data.

15. The system according to claim 14, wherein said microcomputer includes a pair of timers and the predetermined data includes an interrupt program for determining either on duration or off duration of said first chopper circuit from said first duty ratio dependent upon the current conducting state of said first chopper circuit when a first timer outputs an interrupt signal.

16. The system according to claim 15, wherein said interrupt program determines either on duration or off duration of said second chopper circuit from said second duty ratio dependent upon the current conducting state of said second chopper circuit when a second timer outputs an interrupt signal.

17. The system according to claim 15, wherein said two timers are used, in such a way that one timer outputting the interrupt signal whenever the on duration of either first or second chopper circuit is ended and the other timer outputting the interrupt signal whenever the off duration of either first or second chopper circuit is ended.

18. A method for controlling movement of an unmanned vehicle, comprising the steps of:

(a) initializing at least a safety check and a self-diagnosis for a controller installed on the vehicle for controlling movement of the vehicle during movement of the vehicle in various control modes;

(b) storing predetermined data on the various control modes of movement of the vehicle to be carried out when the vehicle moves along a predetermined route of movement stored in a predetermined memory area;

(c) starting the vehicle and reading the predetermined data from the predetermined memory area;

(d) executing control of movement of the vehicle according to the read control mode sequentially read from a head address of the predetermined memory area;

(e) sensing markers placed along the predetermined route and executing the various control modes during movement of the vehicle along the predetermined route of movement based on the total number of said sensed markers; and

(f) repeating the above-described steps (d) and (e) until an end address of the predetermined memory area is read.