Capacitive pointing stick apparatus for symbol manipulation in a graphical user interface

• US 6,184,865 B1
• Filed: 10/23/1996
• Issued: 02/06/2001
• Est. Priority Date: 10/23/1996
• Status: Expired due to Term

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Zimmerman, Thomas G., Smith, Barton Allen
• Primary Examiner(s): NGUYEN, CHANH DUY
• Application Number:
  US08/735,482
• Time in Patent Office: 1,567 Days
• Field of Search: 345/156, 345/161, 345/157, 345/160, 345/159, 345/168, 345/184, 744/71, 341/20, 341/21, 341/22, 463/37, 463/38, 463/39
• US Class Current: 345/160
• 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 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device

Abstract

A structure is provided for a user-manipulable input device, such as an in-keyboard, joystick-type device, for allowing a user to provide input to a computer graphical user interface (GUI). The structure includes a user-manipulable, articulating member, and a plurality of stationary, electrically conductive sensors. The articulating member also has an electrically conductive member. The physical disposition of the articulating member and the sensors provides narrow gaps, across which are measurable capacitances. As the user manipulates the articulating member, the capacitances change in value. Circuitry produces signals related to the capacitances, and the signals are processed, according to a transfer function, to generate GU I input signals. The sensors are preferably sensing electrodes, incorporated into a circuit board. The articulating member is preferably a cone-shaped member, having a conductive surface which faces the sensors. The articulating member is mechanically coupled to the board holding the sensors by a flexing member that biases the articulating member to a quiescent position.

Claims

1. An apparatus for sensing manipulation by a user and for producing signals related to the manipulation in X and Y directions, the apparatus comprising:

an articulating member which articulates responsive to user manipulation thereof, the articulating member including an electrically conductive member;

a planar member;

a plurality of sensing electrodes disposed in parallel to the planar member and about the articulating member to face the electrically conductive member of the articulating member, whereby respective capacitances exist between the electrically conductive member and respective ones of the sensing members, the capacitances having values which vary related to articulation for the articulating member;

detection means for each sensing electrode for detecting respective capacitances and for outputting articulation signals responsive to the detection of the respective capacitances; and

calibration means applied to individual articulation signals for providing a unique scaling value for each articulation signal, wherein the scaling value is calculated from a set of reference values at least one reference value for each sensing electrode, that are dynamically updated.

5. An apparatus as recited in claim 1, further comprising a switch having a first position when the articulating member is not being manipulated, and having a second position, entered when the user manipulates the articulating member.

6. An apparatus as recited in claim 5, wherein the articulating member includes a collapsible member having collapsed and non-collapsed positions, the collapsible member entering the collapsed position responsive to user manipulation of the articulating member, and remaining in the non-collapsed position otherwise.

7. An apparatus as recited in claim 1, wherein:

the apparatus further includes an insulating, dielectric layer disposed on the planar member rover the sensing members; and

the electrically conductive member of the articulating member includes a resilient layer of electrically conductive material, the layer having a textured surface including projections and voids;

whereby, responsive to manipulation of the articulating member, the projections make contact with the insulating layer to establish a capacitive link with the sensing members; and

whereby, responsive to further manipulation of the articulating member, the projections in contact with the insulating layer are deformed so as to increase a quantity of the electrically conductive material of the resilient layer which is in contact with the insulating layer, thereby changing a capacitance value of the capacitive link.

8. The apparatus of claim 1, wherein the sensing electrodes each comprise shapes so as to produce desired transfer functions between articulation of the articulating member and the values of the articulation signals.

9. The apparatus of claim 8, wherein the sensing electrodes each comprise a taper of increasing area.

10. The apparatus of claim 8, wherein the sensing electrodes each comprise a taper of decreasing area.

11. The apparatus of claim 1, wherein the apparatus further senses manipulation in the Z direction and individual articulation signals are summed to produce a signal representing the Z direction component of force applied to said articulating member.

12. The apparatus of claim 1, further comprising means applied to individual articulation signals for providing a quiescent value for each articulation signal indicating the user has ceased manipulation of the articulating member.

13. The apparatus of claim 1, further comprising switch means for receiving a force applied to the articulating member and an output for providing a switch activation signal.

14. The apparatus of claim 13, further comprising:

wake-up means for receiving switch activation signal and for providing a wake-up signal; and

a microprocessor with at least a normal power mode and low power mode, whereby when said microprocessor is in low power mode, said wake-up signal causes said microprocessor to leave the low power mode and enter into the normal power mode.

15. The apparatus of claim 13, wherein said switch means comprise a mechanical switch.

16. The apparatus of claim 13, wherein said switch means further comprise an electrical contact disposed on the planar, whereby contact between the electrically conductive member of the articulating member and said electrical contact occurs when a force is applied to the articulating member.

17. The apparatus of claim 1, wherein said detector means includes an oscillator circuit, whereby the frequency of the oscillator is dependent on the value of the respective capacitance, further comprising selection means to sequentially enable each oscillator in a temporal sequence.

18. The apparatus of claim 1, further comprising switch means for receiving a force applied to the articulating member and an output for providing a switch activation signal.

19. The apparatus of claim 18, further comprising:

wake-up means to receive switch activation signal and output a wake-up signal; and

a microprocessor comprising at least a normal power mode and a low power mode, whereby when said microprocessor is in the low power mode, said wake-up signal causes said microprocessor to leave the low power mode and enter into the normal power mode.

20. The apparatus of claim 18, wherein said switch means comprise a mechanical switch.

21. The apparatus of claim 18, wherein said switch means comprise an electrical contact disposed on the planar, whereby contact between the electrically conductive member of the articulating member and said electrical contact occurs when a force is applied to the articulating member.

2. An apparatus as recited in claim 2, wherein the articulating member includes:

an anchoring member rigidly coupled to the planar member;

a movable member which is movable responsive to user manipulation thereof; and

a coupling member, physically coupled between the anchoring member and the movable member, the coupling member being flexible to allow movement of the movable member relative to the anchoring member.

3. An apparatus as recited in claim 2, wherein:

the anchoring member is annular in shape; and

the coupling member is shaped so as to have a quiescent position and a collapsed position, a physical transition between the quiescent position and the collapsed position providing a user with tactile feedback.

4. An apparatus as recited in claim 3, wherein the coupling member is one of (i) dome-shaped and (ii) shaped as an annular arch.

22. An apparatus for sensing manipulation by a user and for producing signals related to the manipulation in X and Y directions, the apparatus comprising:

an articulating member which articulates responsive to user manipulation thereof, the articulating member including an electrically conductive member;

a plurality of sensing electrodes disposed about the articulating member to face the electrically conductive member, whereby respective capacitances exist between the electrically conductive member and respective ones of the sensing electrodes, the capacitances having values which vary related to articulation for the articulating member;

calibration means applied to individual articulation signals to provides a unique scaling value for each articulation signal, wherein said scaling value is calculated from a set of reference values, at least one reference value for each sensing electrode, that are dynamically updated; and

an oscillator circuit for each sensing electrode, wherein the frequency of the oscillator is dependent on the value of the respective capacitance, selection means to sequentially enable each oscillator in a temporal sequence.

23. The apparatus of claim 22, wherein the sensing electrodes each comprise shapes so as to produce desired transfer functions between articulation of the articulating member and the values of the articulation signals.

24. The apparatus of claim 23, wherein the sensing electrodes each comprise a taper of increasing area.

25. The apparatus of claim 23, wherein the sensing electrodes each comprise a taper of decreasing area.

26. The apparatus of claim 23, further comprising calibration means applied to individual articulation signals for providing a quiescent value for each articulation signal indicating the user has ceased manipulation of the articulating member.

27. The apparatus of claim 22, wherein the scaling value is calculated from a set of reference values, at least one reference value for each sensing electrode, that are dynamically updated.

28. The apparatus of claim 22, further comprising switch means to receive force applied to the articulating member and output a switch activation signal.

29. The apparatus of claim 28, further comprising:

a wake-up means for receiving a switch activation signal and for providing a wake-up signal; and

a microprocessor with at least a normal power mode and low power mode, whereby when said microprocessor is in low power mode, said wake-up signal causes said microprocessor to leave the low power mode and go into normal power mode.

30. The apparatus of claim 28, wherein said switch means comprise a mechanical switch.

31. The apparatus of claim 28, wherein said switch means further comprise an electrical contact disposed on the planar, whereby contact between the electrically conductive member of the articulating member and said electrical contact occurs when a force is applied to the articulating member.

32. The apparatus of claim 22, wherein the sensing each electrodes comprise shapes so as to produce desired transfer functions between articulation of the articulating member and the values of the articulation signals.

33. The apparatus of claim 32, wherein the sensing electrodes each comprise a taper of increasing area.

34. The apparatus of claim 30, wherein the sensing electrodes each comprise a taper of decreasing area.

35. The apparatus of claim 22, wherein the apparatus further senses manipulation in the Z direction and individual articulation signals are summed to produce a signal representing the Z component of force applied to said articulating member.

36. The apparatus of claim 22, further including calibration means applied to individual articulation signals for providing a quiescent value for each articulation signal indicating the user has ceased manipulation of the articulating member.