Automatic vehicle-monitoring system

• US 3,886,515 A
• Filed: 05/24/1973
• Issued: 05/27/1975
• Est. Priority Date: 05/26/1972
• Status: Expired due to Term

• Current Assignee: Jean Cottin, Jean Laxaque
• Original Assignee: Jean Cottin, Jean Laxaque
• Inventors: Cottin, Jean, Laxaque, Jean
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Myers, Randall P.
• Application Number:
  US05/363,729
• Time in Patent Office: 733 Days
• Field of Search: 235/150.2,150.24 340/22,23,24,31R,32,33,38R,38L
• US Class Current: 340/994
• CPC Class Codes: B61L 25/023 Determination of driving direction of vehicle or train
• CPC Class Codes: B61L 25/026 Relative localisation, e.g. using odometer
• CPC Class Codes: B61L 27/40 Handling position reports or trackside vehicle data
• CPC Class Codes: G08G 1/123 indicating the position of vehicles, e.g. scheduled vehicles; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, tramstransmission of navigation instructions to vehicles G08G1/0968

Abstract

A plurality of public-transport surface vehicles such as buses, each identified by an individual number, are equipped with transmitters for sending out that identification number together with heading and positional data conveying information on direction of travel and momentary distance from a point of departure; the transmitted information may also indicate the state of occupancy of the vehicle. This information is received at transit points along the route, each transit point including circuits for determining from the directional and distance data the distance of an approaching vehicle from that point. If the transit point is a passenger station, the shortest vehiclular distance or distances are registered with the accompanying identification and occupancy data in one or more stores for display to waiting passengers. The directional and distance data can also be intercepted by a traffic-control post to detect the approach of vehicles at an intersection as an aid in the operation of traffic lights. The data-evaluating equipment at any such transit point includes a comparator determining whether a newly arriving signal is from a vehicle whose data have already been registered in a store thereof, i.e. whether the transmitting vehicle is among those closest to that point at the instant of reception.

Claims

1. A system for automatically monitoring a plurality of surface vehicles equipped with transmitting means for intermittently sending out messages including positional data indicating the distance Dv of the vehicle, along a predetermined route, from a fixed reference point common to all vehicles, comprising:

receiving means located at a transit point along the route of said vehicles for picking up the transmitted messages;

data-supply means at said transit point for indicating the distance Ds thereof from said reference point;

data-supply means at said transit point connected to said receiving means and to said arithmetic means for calculating from said distances Dv and Ds the sign and magnitude of the instantaneous distance De of the vehicle from said transit point;

storage means at said transit point connected to said arithMetic means for registering the magnitude of the vehicular distance De in response to a sign of said vehicular distance De indicating that the vehicle is approaching said transit point; and

output means connected to said storage means for revealing the approach of a vehicle.

2. A system as defined in claim 1 wherein different vehicles move along several routes past said transit point, said storage means being assigned to vehicles traveling over only one of said routes identified by heading data transmitted as part of each message, further comprising discriminating means at said transit point connected to said receiving means for detecting said heading data and for enabling said storage means to register said vehicular distance De.

3. A system as defined in claim 1, further comprising a data source at said transit point indicating a reference distance Da and comparison means at said transit point connected to said arithmetic means and to said data source for determining the relative magnitudes of said vehicular distance and said reference distance, said storage means being controlled by said comparison means to register the magnitude of said vehicular distance De only upon the latter magnitude being less than said reference distance.

4. A system as defined in claim 3 wherein said data source comprises read-out means for said storage means carrying distance information registered therein, and access means controlled by said comparison means for enabling the contents of said storage means to be modified on arrival of a message from a vehicle whose distance from said transit point is less than a previously registered vehicular distance De.

5. A system as defined in claim 3 wherein the messages transmitted by each vehicle include an identification code, said storage means being further connected to said receiving means for registering the identification code of an approaching vehicle together with the magnitude of said vehicular distance De thereof.

6. A system as defined in claim 5, further comprising a comparator connected to said storage means and to said receiving means, and access means controlled by said comparator for enabling the contents of said storage means to be updated on arrival of a subsequent message from a vehicle whose identification code is already registered in said storage means.

7. A system as defined in claim 5 wherein said reference distance Da has a fixed value and said transit point is a traffic-control post, said output means comprising a source of control signals for a traffic light at said post responding to the presence of an approaching vehicle within a zone of action represented by said reference distance.

8. A system as defined in claim 3 wherein said transit point is a passenger station along a route traveled by said vehicles, said output means including local display means for indicating the magnitude of said vehicular distance De.

9. A system as defined in claim 8 wherein said storage means comprises a first store and a second store, and a preference circuit for loading said first store before loading said second store.

10. A system as defined in claim 9 wherein said data source comprises first read-out means of said first store and second read-out means of said second store carrying distance information respectively registered therein, said comparison means including a first comparison circuit connected to said arithmetic means and to said first read-out means and a second comparison circuit connected to said arithmetic means and to said read-out means, said first store being provided with first access means controlled by said first comparison circuit for enabling the contents of said first store to be modified on arrival of a message from a vehicle whose distance De from said transit point is less than a vehicular distance De1 registered in said first store, said second store being provided with second access means controlled by said sEcond comparison circuit for enabling the contents of said second store to be modified on arrival of a message from a vehicle whose distance De from said transit point is less than a vehicular distance De2 registered in said second store.

11. A system as defined in claim 10, further comprising a first comparator connected to said first store and to said receiving means, and a second comparator connected to said second store and to said receiving means, said first access means being additionally controlled by said first comparator for enabling the contents of said first store to be updated regardless of vehicular distance on arrival of a subsequent message from a vehicle whose identification code is already registered in said first store, said second access means being additionally controlled by said second comparator for enabling the contents of said second store to be updated regardless of vehicular distance on arrival of a subsequent message from a vehicle whose identification code is already registered in said second store.

12. A system as defined in claim 11 wherein said preference circuit includes blocking means controlled by said first comparator for preventing entry in said second store of data from a vehicle whose identification code is registered in said first store.

13. A system as defined in claim 12 wherein said preference circuit further includes clearing means jointly controlled by said first and second comparators for emptying said second store upon concurrent entry of the same identification code in both stores.

14. A system as defined in claim 11 wherein said preference circuit includes a lead energized by said receiving means with a timing pulse of predetermined duration upon the arrival of a message from any vehicle, and delay means for feeding said timing pulse successively to said first access means and to said second access means, both said access means being inoperative in the absence of said timing pulse.

15. A system as defined in claim 14 wherein said delay means comprises a first stage with a delay less than said duration between said receiving means and said first access means and a second stage with a delay greater than said duration between said first stage and said second access means.