VEHICLE SELF-TRACKING SYSTEM

• US 3,681,752 A
• Filed: 10/08/1970
• Issued: 08/01/1972
• Est. Priority Date: 10/08/1970
• Status: Expired due to Term

• Current Assignee: Richard G. Cuddihy
• Original Assignee: Richard G. Cuddihy
• Inventors: Cuddihy, Richard G.
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Brauner, Horst F.
• Application Number:
  US05/079,015
• Time in Patent Office: 663 Days
• Field of Search: 340/24,22 343/112 346/8 116/29,35 178/18
• US Class Current: 340/995.26
• CPC Class Codes: G01C 21/22 Plotting boards

Abstract

A system for permitting the operator of a motor vehicle to determine the location of his vehicle relative to a map includes an indicator movable beneath the map and having a concentrated light source which shines through the map to give the vehicle location. The drive and steering of the indicator are electrically slaved to the linear speed and turning movements of the vehicle. The indicator includes a steerable drive wheel which may engage a mode of the terrain shown by the map or a flat surface if any error which might be introduced by the latter is within the limits of tolerance desired. The electronic circuitry for the drive and steering of the indicator includes a main pulse generator having an output frequency related to the instantaneous speed of the vehicle and a further pulse generator having alternate pulse outputs whose pulse durations are variable in opposite sense with respect to each other in response to steering movements imparted to the vehicle. The indicator drive is controlled by the speed-related pulses whereas steering of the indicator is effected by ANDing signals derived from both circuits. The circuitry includes a novel pulse generator for producing the alternate pulses.

Claims

1. A visual self-tracking device for motor vehicles comprising, in combination, a map display of the locale within which a motor vehicle is operating;

indicator means for following the course of the vehicle with respect to said display;

carrier means for said indicator means;

traction means for moving said carrier means linearly in consonance with the linear movement of said vehicle; and

means for rotationally orienting said traction means in consonance with turning movement imparted to said vehicle.

2. The self-tracking device according to claim 1, wherein said map display is an orthogonal projection, said traction means including a drive wheel, and a reaction surface over which said drive wheel moves, said reaction surface being contoured according to the contour of the terrain of the said locale.

3. The self-tracking device according to claim 2, wherein said carrier means includes a carriage, orthogonal guide means for allowing said carriage freely to traverse along orthogonal axes, a platform rotatably mounted on said carriage, said traction means including a drive wheel carried by said platform and having its contact point aligned along the axis of rotation of said platform, and said means for rotationally orienting being connecting to rotate said platform.

4. The self-tracking device according to claim 1, wherein said carrier means includes a carriage, orthogonal guide means for allowing said carriage freely to traverse along orthogonal axes, a platform rotatably mounted on said carriage, said traction means including a drive wheel carried by said platform and having its contact point aligned along the axis of rotation of said platform, and said means for rotationally orienting being connected to rotate said platform.

5. The self-tracking device according to claim 1, including a trigger means for producing output pulses at a frequency related to the linear speed of said vehicle, said traction means including a stepping motor controlled by said trigger means, oscillator means having successive output pulses separated by a fixed time interval and whose pulse durations are alternately oppositely variable according to the steering orientation of said vehicle, gate means for passing successive pairs of pulses from said trigger means in response to the pulse durations of alternate output pulses of said oscillator means, said means for orienting including stepping motor means controlled by said gate means.

6. The self-tracking device according to claim 1, including pulse generator means associated with each of the two steerable wheels of the vehicle, a pair of pulse generators each having a duty cycle adjusted to near unity, an AND gate for each pulse generator Means and an associated pulse generator, a further AND gate having the output of one of the aforesaid AND gates as an input thereto, a further pulse generator having its output as the other input to said further AND gate, said further pulse generator having a duty cycle adjusted to near unity, said traction means including a stepping motor controlled by said further AND gate, said means for orienting including stepping motor means controlled by said aforesaid AND gates.

7. A visual tracking device for motor vehicles comprising in combination:

a map display of the locale within which a motor vehicle is operating and adapted to be mounted in the motor vehicle;

indicator means for indicating the position of the vehicle with respect to the map display; and

drive means for slaving said indicator means to vehicle movement, said drive means including first and second gate means for producing pulse outputs whose repetition rates are related respectively to left and right turning motions of the vehicle, and means for controlling the azimuthal alignment of said indicator means in accord with said pulse outputs.

8. The visual tracking device according to claim 7, wherein said drive means also includes a multivibrator having two outputs connected respectively to said first and second gate means, said multivibrator having input means controlled by steering motions imparted to the vehicle for causing said two outputs to be asymmetrical when steering motion is imparted to the vehicle.

9. The visual tracking device according to claim 7, wherein said drive means also includes a pair of multivibrators one of which is associated with said first gate means and the other of which is associated with said second gate means, each multivibrator having two outputs of which only one is connected to an associated gate means and each having input means for producing asymmetry between its outputs.

10. The tracking device according to claim 9 wherein said drive means also includes first and second switch means associated with the left and right steerable wheels of the vehicle and each having a pulse output whose frequency is related to the rotational speed of its associated wheel, the outputs of said switch means being connected respectively to said first and said second gate means.

11. The tracking device according to claim 10 wherein said drive means also includes further gate means for controlling the speed of movement of said indicator means, a further multivibrator having nonsymmetrical outputs of which one is connected to said further gate means, and the output of one of said first and said second gate means being connected to said further gate means.

12. The tracking device according to claim 10 wherein said drive means also includes a bistable device having delayed pulse outputs of said first and said second gate means as its inputs, and third and fourth gate means having the outputs of said bistable device as respective inputs and also having the pulse outputs of said first and said second gate means as respective inputs.

13. The tracking device according to claim 12 wherein said drive means also includes first and second stepping motors for controlling said indicator means in azimuth, the outputs of said third and said fourth gate means being connected respectively to said first and said second stepping motors.

14. The tracking device according to claim 7 wherein said drive means also includes a bistable device having delayed pulse outputs of said first and said second gate means as inputs thereto, and third and fourth gate means having the outputs of said bistable device as respective inputs and also having the pulse outputs of said first and said second gate means as respective inputs.

15. The tracking device according to claim 14 wherein said drive means also includes first and second stepping motors for controlling said indicator means in azimuth, the outputs of said third and said fourth gate means being connected respectively to said firsT and said second stepping motors.

16. The tracking device according to claim 7 wherein said drive means also includes pulse generator means having a pulse output whose repetition rate is proportional to vehicle speed, the pulse output of said pulse generator means being connected as inputs to said first and said second gate means.

17. The tracking device according to claim 16 wherein said drive means also includes a stepping motor connected to the output of said pulse generator means for moving said indicator means in proportion to vehicle speed.