GUIDANCE SYSTEM FOR SELF-PROPELLED TRACKLESS CARRIAGES

• US 3,628,624 A
• Filed: 09/24/1969
• Issued: 12/21/1971
• Est. Priority Date: 04/26/1967
• Status: Expired due to Term

• Current Assignee: Wesener Erich
• Original Assignee: Wesener Erich
• Inventors: WESENER ERICH
• Application Number:
  US04/860,566
• Time in Patent Office: 818 Days
• US Class Current: 180/168
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: G05D 1/0244 using reflecting strips
• CPC Class Codes: G05D 1/0263 using magnetic strips

Abstract

A trackless carriage with two individually drive lateral traction wheels has four sensors, disposed in a diamond-shaped array, which coact capacitively or inductively with a continuous guide strip on the floor to steer the vehicle along a predetermined path by controlling the transmission of driving torque to these wheels. When the two sensors on the longitudinal diagonal of the array register with the strip, both traction wheels are driven; when either or both of these sensors are out of line and one of the two other sensors, on the transverse diagonal, detects the proximity of the strip, the opposite traction wheel is driven to realign the vehicle with the guide path.

Claims

1. A system for guiding a self-propelled carriage, comprising:

a substantially continuous strip of distinctive character at the level of a floor establishing a predetermined path for the guidance of a carriage traveling over said floor;

a right-hand traction wheel and a left-hand traction wheel on said carriage;

first and second drive means aboard said carriage for transmitting torque to said right-hand and left-hand traction wheels, respectively; and

a control circuit for said first and second drive means including central sensing means and flanking right and left sensing means responsive to said guide means for emitting a steering signal upon detecting the proximity of said strip, said first and second drive means being jointly responsive to a steering signal from said central sensing means to power both said traction wheels simultaneously, said first drive means being responsive to a steering signal from said left sensing means to pOwer said right-hand traction wheel, said second drive means being responsive to a steering signal from said right sensing means to power said left-hand traction wheel;

said central sensing means comprising first and second sensors spaced apart in the direction of travel, said right and left sensing means comprising third and fourth sensors spaced apart on a line transverse to said direction of travel;

said control circuit including an individual oscillator for each of said sensors, said oscillator being provided with a reactive circuit, each of said sensors forming together with said strip a reactance connected in said reactive circuit for resonating same at a predetermined operating frequency whereby the alignment of any sensor with said strip tunes the associated oscillator to said operating frequency indicating such alignment.

2. A system as defined in claim 1 wherein said sensors form a diamond-shaped array.

3. A system for guiding a self-propelled carriage, comprising:

a substantially continuous strip of distinctive character at the level of a floor establishing a predetermined path for the guidance of a carriage traveling over said floor;

a right-hand traction wheel and a left-hand traction wheel on said carriage;

first and second drive means aboard said carriage for transmitting torque to said right-hand and left-hand traction wheels, respectively; and

a control circuit for said first and second drive means including central sensing means and flanking right and left sensing means responsive to said guide means for emitting a steering signal upon detecting the proximity of said strip, said right and left sensing means comprising individual sensors spaced apart on a line transverse to said direction of travel, said first and second drive means being jointly responsive to a steering signal from said central sensing means to power both said traction wheels simultaneously, said first drive means being responsive to a steering signal from said left sensing means to power said right-hand traction wheel, said second drive means being responsive to a steering signal from said right sensing means to power said left-hand traction wheel;

said control circuit including an individual oscillator for each of said sensors, said oscillator being provided with a reactive circuit, each of said sensors forming together with said strip a reactance connected in said reactive circuit for resonating same at a predetermined operating frequency whereby the alignment of any sensor with said strip tunes the associated oscillator to said operating frequency indicating such alignment.

4. A system as defined in claim 3 wherein said central, right and left sensing means are disposed ahead of said traction wheels as viewed in the direction of travel.

5. A system as defined in claim 4 wherein said first and second drive means are reversible, further comprising alternatively operable duplicates of said central, right and left sensing means disposed symmetrically thereto on the opposite side of a common axis of said traction wheels.

6. A system as defined in claim 3 wherein said traction wheels are coaxial, said individual sensors being disposed between said traction wheels substantially in line with the common axis thereof.

7. A system as defined in claim 3 wherein the spacing of said individual sensors is substantially equal to twice the width of said strip.

8. A system as defined in claim 3 wherein said control circuit further includes filter means in the output of each oscillator tuned to said operating frequency for generating the corresponding steering signal.

9. A system as defined in claim 3 wherein said strip splits into different branches on at least one junction point, further comprising marker means at said junction point and detector means aboard said carriage settable to respond to said a market means for modifying the operation of said control circuit to direct the carriage onto a selected branch.

10. A system as defined in claim 9 Wherein said marker means comprises an array of magnets on said floor, said detector means comprising magnetic switches positioned to respond to certain of said magnets upon alignment therewith.

11. A system as defined in claim 3, further comprising obstacle-detecting means aboard said carriage and switch means responsive to said obstacle-detecting means for deactivating said first and second drive means.

12. A system as defined in claim 3 wherein said carriage is provided with two swivelable nondriven wheels supplementing said traction wheels.