Data communications between fixed and moving terminals

• US 4,284,941 A
• Filed: 10/05/1979
• Issued: 08/18/1981
• Est. Priority Date: 10/05/1979
• Status: Expired due to Term

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Regueiro, William R.
• Primary Examiner(s): Dobeck, B.
• Application Number:
  US06/082,297
• Time in Patent Office: 683 Days
• Field of Search: 318/16, 318/587, 318/653, 180/168, 179/82
• US Class Current: 318/587
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: G05D 1/0265 using buried wires

Abstract

A data communications system between fixed and moving terminals wherein a conductor connected to the fixed terminal and disposed in the travel path of the moving terminals supports lateral guidance control information for the moving terminals as well as two-way inductive data communications between the fixed terminal and the moving terminals. The fixed (wayside) terminal transmits over the conductor an alternating current lateral guidance signal modulated in accordance with longitudinal control information for each of the moving terminals. Each of the moving terminals, in turn, transmits status information over the conductor to be used for developing control information at the fixed terminal. The fixed terminal employs hybrid transformer techniques in conjunction with precision filtering to enable reception of low-level status information from the moving terminals and concurrent rejection of the modulated lateral guidance signal and other interfering signals.

Claims

1. A communications system for automated guidance transportation wherein a vehicle communicates status information to a wayside installation and the wayside installation communicates lateral guidance and control information to the vehicle comprising:

a conductor defining a course over which said vehicle is to travel, said conductor having a loop closing portion whereat the ends of said conductor form loop terminals;

first and second wayside transformers, each of said transformers having first, second, and third windings;

a first circuit comprising in series connection, said third windings of said first and second transformers and said loop terminals;

an electrical load having an impedance substantially matched with that of said conductor;

a second circuit comprising in series connection said load and the first windings of said first and second transformers;

means connecting said second winding of said first transformer to a wayside transmitter for applying a lateral guidance signal to said conductor and for modulating said guidance signal in accordance with control information for said vehicle;

means connecting said second winding of said second transformer to a wayside receiver for receiving information transmitted into said conductor by said vehicle, the turns ratio and relative winding polarity of said transformer windings being such that signals transmitted from a vehicle into said conductor are received in said wayside receiver, and signal transmitted by said wayside transmitter for reception by said vehicle induce substantially equal and opposite voltages in said second winding of said second transformer to thereby substantially isolate said wayside receiver from signals transmitted by said wayside transmitter.

2. A communications system for automated guidance transportation wherein a vehicle communicates status information to a wayside installation and the wayside installation communicates lateral guidance and control information to the vehicle comprising:

a guideway conductor terminated substantially at its midpoint by an electrical guideway impedance, the ends of said conductor and said electrical impedance being arranged so that said conductor defines a closed course for said vehicle;

first and second wayside transformers, each of said transformers having first, second and third windings;

a first wayside circuit comprising in series connection said third windings of said first and second transformers and the ends of said guideway conductors;

an electrical load having an impedance substantially matched with the combined impedance of said guideway conductor and said guideway impedance;

a second wayside circuit comprising in series said electrical load and the first windings of said first and second transformers;

means connecting said second winding of said first transformer to a wayside transmitter for applying a lateral guidance signal to said guideway conductor and for modulating said guidance signal in accordance with control information for said vehicle;

means connecting said second winding of said second transformer to a wayside receiver for receiving information transmitted into said guideway conductor by said vehicle, the turns ratio and relative winding polarity of said transformer windings being such that signals transmitted from a vehicle into said guideway conductor are received in said wayside receiver, and signals transmitted by said wayside transmitter for reception by said vehicle induce substantially equal and opposite voltages in said second winding of said second transformer to thereby substantially isolate said wayside receiver from signals transmitted by said wayside transmitter.

3. A communication system for automated guidance transportation wherein a vehicle communicates status information to a wayside installation and the wayside installation communicates lateral guidance and control information to the vehicle comprising:

a travel path for said vehicle defined by portions of first and second conductors, at least one end of each of said travel path portions being arranged in close proximity with the other in substantially linear relationship;

a first circuit comprising in series connection said third windings of said first and second transformers and the ends of said first conductor;

a second circuit comprising in series connection said first windings of said first and second transformers and the ends of said second conductor;

means connecting said second windings of said first transformer to a wayside transmitter for applying a lateral guidance signal to said first and second conductors and for modulating said guidance signal in accordance with control information for said vehicle;

means connecting said second windings of said second transformer to a wayside receiver for receiving information transmitted into said first or second conductors by said vehicle, the turns ratio and relative winding polarity of said transformer windings being such that signals transmitted from a vehicle into said first or second conductors are received in said wayside receiver, and signals transmitted by said wayside transmitter for reception by said vehicle, produce substantially equal and opposite signals in said second winding of said second transformer to thereby substantially isolate said wayside receiver from signals transmitted by said wayside transmitter.