Joystick with membrane sensor

• US 5,689,285 A
• Filed: 05/02/1995
• Issued: 11/18/1997
• Est. Priority Date: 09/13/1993
• Status: Expired due to Fees

• Current Assignee: David J. Asher
• Original Assignee: David J. Asher
• Inventors: Asher, David J.
• Primary Examiner(s): WU, XIAO MIN
• Application Number:
  US08/434,456
• Time in Patent Office: 931 Days
• Field of Search: 345/161, 345/157, 345/156, 345/173, 345/174, 345/159, 200/6 A, 200/5 R, 200/17 R, 200/6 R, 273/148 B, 273/DIG. 28, 74/471 XY, 463/38
• US Class Current: 345/161
• CPC Class Codes: G05G 9/047 the controlling member being movable by hand about orthogonal axes, e.g. joysticks for switches H01H25/04
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: Y10T 74/20201 Control moves in two planes

Abstract

A joystick for generation of directional control signals for computers, video games, remote controllers, and other electronic devices and instrumentation. The present invention comprises a resistive membrane sensor and an actuator for coupling directional forces onto the membrane sensor. The resistive membrane sensor is comprised of two insulating substrates with resistor rings on each substrate, conductive leads, and a pressure-variable resistor. Increasing pressure on the actuator and membrane sensor decreases the resistance of the pressure-variable resistor in series with the resistor rings. An electronic circuit measures the membrane sensor and converts the resistances into the X and Y components of the force vector acting on the joystick. An alternative membrane sensor comprises a resistive ring, a conductive ring, and a pressure-variable resistor.

Claims

1. A joystick for generating directional control signals, said joystick comprising:

first and second insulating substrates, each of said first and second insulating substrates having a first surface region, said first and second insulating substrates being positioned to place said first surface regions of said first and second substrates in spaced apart substantially parallel relationship with one another;

a first resistor defined by a closed-loop conductive pattern on said first surface region of said first insulating substrate;

first and second electrical conductors, said first and second electrical conductors being in electrical contact with said first resistor at spaced apart locations of said closed-loop conductive pattern that defines said first resistor to partition said closed-loop conductive pattern into first and second electrically parallel resistance paths;

each of said first and second parallel resistance paths of said first resistor extending between said first and second electrical conductors;

a second resistor defined by a closed-loop conductive pattern of substantially the same geometry as the geometry of said closed-loop conductive pattern that defines said first resistor, said second resistor being located on said first surface region of said second insulating substrate and being in spaced apart substantial spatial registration with said first resistor;

third and fourth electrical conductors, said third and fourth electrical conductors being in electrical contact with said second resistor at first and second spaced apart locations of said closed-loop conductive pattern that defines said second resistor to partition said closed-loop conductive pattern into first and second electrically parallel resistance paths;

each of said first and second parallel resistance paths of said second resistor extending between said third and fourth electrical conductors;

a pressure-sensitive resistive material, interposed between said first surfaces of said spaced apart first and second substrates, said pressure-sensitive resistive material exhibiting a resistance value representative of an applied contacting force; and

an actuator positioned for operative interaction with one of said first and second insulating substrates, said actuator being radially deflectable to apply a localized pressure on said one of said first and second insulating substrates;

said localized pressure acting on said pressure sensitive resistive material to establish a resistive signal path at the location of said localized pressure and extending between said first and second resistors, the resistance of said resistive signal path to thereby establish a first resistance value between said first and second conductors of said first resistor and a second resistance value between said third and fourth conductors of said second resistor, said first and second resistance values being representative of the direction of radial deflection of said actuator.

2. The joystick of claim 1 wherein said pressure sensitive resistive material forms at least one of the closed-loop patterns that defines said first and second resistors so that said signal path between said first and second resistors exhibits a resistance that is representative of the force exerted on the radially deflected actuator.

3. The joystick of claim 1 wherein said pressure sensitive resistive material is deposited on and is in contact with at least one of said first and second resistors, said deposited pressure-sensitive resistive material establishing said resistive signal path between said first and second resistors when said actuator is radially deflected and exhibiting a resistance value representative of the force of radial deflection.

4. The joystick of claim 1 wherein each of said closed-loop conductive patterns that define said first and second resistors are of annular geometry;

said first and second conductors are in electrical contact with said conductive pattern that defines said first resistor at diametrically opposed locations;

said third and fourth conductors are in electrical contact with said conductive pattern that defines said second resistor at diametrically opposed positions that are circumferentially spaced apart from the electrical contact points of said first resistor by substantially 90°

.

5. The joystick of claim 4 wherein at least one of the closed-loop patterns that defines said first and second resistors is formed of said pressure sensitive resistive material so that said signal path between said first and second resistors exhibits a resistance that is representative of the force exerted on said radially deflected actuator.

6. The joystick of claim 4 wherein said pressure sensitive resistive material is deposited on and is in contact with at least one of said first and second resistors, said deposited pressure-sensitive resistive material establishing said resistive signal path between said first and second resistors when said actuator is radially deflected and exhibiting a resistance value representative of the force of radial deflection.

7. The joystick of claim 1 wherein said closed-loop conductive path that defines said first resistor further defines a third resistance path that extends between said first and second conductors and said closed-loop conductive path that defines said second resistor further defines a third resistance path that extends between said third and fourth conductors of said second resistor.

8. The joystick of claim 7 wherein said closed-loop conductive patterns that define said first and second resistors are annular in geometry with said first and second conductors electrically contacting diametrically opposed locations along said closed-loop pattern that defines said first resistor and said third and fourth conductors electrically contacting said second resistor at diametrically opposed locations along said closed-loop pattern that defines said second resistor;

and, wherein said third resistance paths of said first and second resistors respectively extend between said first and second conductors and between said third and fourth conductors.

9. The joystick of claim 8 wherein said pressure sensitive resistive material forms at least one of the closed-loop patterns that defines said first and second resistors so that said signal path between said first and second resistors exhibits a resistance that is representative of the force exerted on the radially deflected actuator.

10. The joystick of claim 8 wherein said pressure sensitive resistive material is deposited on and is in contact with at least one of said first and second resistors, said deposited pressure-sensitive resistive material establishing said resistive signal path between said first and second resistors when said actuator is radially deflected and exhibiting a resistance value representative of the force of radial deflection.

11. The joystick of claim 1 further comprising switching means, a voltage source having first and second supply terminals and third and fourth resistors;

said third and fourth resistors being connected in series with one another across said voltage source first and second supply terminals, said switching means having a pair of input terminals electrically connected to said first and second conductors of said first resistor and having a pair of input terminals electrically connected to said third and fourth conductors of said second resistor, said switching means having a first operational mode for electrical connection of said voltage source across said first and second conductors of said first resistor and for concurrent electrical connection of said third and fourth conductors of said second resistors to the junction between said serially connected third and fourth resistors;

said switching means having a second operational mode for electrical connection of said voltage source across said third and fourth conductors of said second resistor and for concurrent electrical connection of said first and second conductors of said first resistor to the junction between said serially connected third and fourth resistors.

12. A joystick for generating directional control signals comprising first and second insulating substrates, said first insulating substrate having a surface region for containment of a resistive element, said second insulating substrate having a surface region for containment of a conductive element, said first and second insulating substrates being in substantially parallel spaced apart juxtaposition with one another with said surface region of said first insulating substrate facing said surface region of said second insulating substrate;

a first resistor defined by a closed-loop conductive pattern on said surface region of said first insulating substrate;

first, second, third and fourth conductors, said first, second, third and fourth conductors electrically connected to spaced apart locations along said closed-loop conductive pattern that defines said first resistor, said first and second conductors partitioning said first resistor into two parallel resistive paths that extend between said first and second conductors, said third and fourth conductors partitioning said first resistor into two resistive paths that extend between said third and fourth conductors;

a conductive pattern of relatively low resistivity deposited on said surface of said second insulating substrate, said conductive pattern being of substantially the same geometry as the geometry of said closed-loop conductive pattern that defines said first resistor;

a fifth conductor electrically connected to said conductive pattern that is located on said surface of said second insulating substrate;

an actuator manually deflectable in a selected direction to establish a resistive signal path between said fifth conductor and a location on said closed-loop conductive pattern that is determined by the direction in which said actuator is deflected; and

a pressure-variable resistance material interposed between said first and second substrates, said actuator being radially deflectable to contact one of said first and second substrates, said contact applying a localized pressure on said pressure-variable resistance material to establish said resistive signal path between said fifth conductor and said closed-loop conductive pattern at a resistance value that is representative of the force applied to said actuator.

13. The joystick of claim 12 wherein said closed-loop pattern that defines that first resistor is formed of said pressure-variable resistance material to establish said signal path between said fifth conductor and said closed-loop conductive pattern of said first resistor when said actuator is deflected.

14. The joystick of claim 13 wherein the pressure-variable resistance material is deposited on and is in contact with at least one of said first resistor and said conductive pattern on said surface of said second insulating substrate, said deposited pressure-variable resistance material establishing said resistive signal path between said conductive pattern of said first resistor and said fifth conductor when said actuator is radially deflected, said resistive signal path exhibiting said resistance value representative of the force of said radial deflection.

15. The joystick of claim 12 wherein said closed-loop conductive pattern that defines said first resistor and said conductive pattern on said surface of said second insulating substrate are annular in geometry and wherein said first, second, third and fourth conductors are electrically connected to equally spaced apart points along the circumference of said annular geometry of said first resistor.

16. The joystick of claim 15 wherein said closed-loop pattern said defines that first resistor is formed of a pressure-variable resistance material to establish said signal path between said filth conductor and said closed-loop conductive pattern of said first resistor when said actuator is deflected.

17. The joystick of claim 15 wherein the pressure-variable resistance material is deposited on and is in contact with at least one of said first resistor and said conductive pattern on said surface of said second insulating substrate, said deposited pressure-variable resistance material establishing said resistive signal path between said conductive pattern of said first resistor and said fifth conductor when said actuator is radially deflected, said resistive signal path exhibiting said resistance value representative of the force of said radial deflection.

18. The joystick of claim 12 further comprising:

analog switching means for selectively interconnecting a predetermined voltage between said first and second conductors of said first insulating substrate or said third and fourth conductors of said first insulating substrate; and

a current summing amplifier electrically connected to said fifth conductor on said second insulating substrate.