Capacitively coupled multiple axis data input apparatus and method

• US 5,786,997 A
• Filed: 06/18/1996
• Issued: 07/28/1998
• Est. Priority Date: 06/20/1995
• Status: Expired due to Fees

• Current Assignee: Ziba Design, Inc.
• Original Assignee: Ziba Design, Inc.
• Inventors: Brown, Neil L., Hoyt, Joshua K., Leppo, William D.
• Primary Examiner(s): Gordon, Paul P.
• Assistant Examiner(s): Garland, Steven R.
• Application Number:
  US08/666,619
• Time in Patent Office: 770 Days
• Field of Search: 364/190, 364/709.11, 73/862.68, 73/862.043, 73/724, 463/38, 200/6 A, 341/20, 341/33, 361/283.2, 361/300, 361/290, 74/471 XY, 345/156-158, 345/161
• US Class Current: 700/85
• CPC Class Codes: G05G 2009/0474 characterised by means converting mechanical movement into electric signals
• CPC Class Codes: G05G 2009/04755 Magnetic sensor, e.g. hall generator, pick-up coil
• CPC Class Codes: G05G 2009/04777 with additional push or pull action on the handle
• CPC Class Codes: G05G 2009/04781 with additional rotation of the controlling member
• 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: G05G 9/04737 with six degrees of freedom
• 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 capacitively coupled, six axis joystick (320) employs a sensor electrode (310) having a perpendicular pair of slots (312, 314) and a fixed electrode assembly (300) having capacitor electrodes (C_S) formed on three mutually orthogonal surfaces of planar circuit boards (302, 304, 306) that are complementarily nested within the slots of the sensor electrode. When nested together, the capacitor electrodes are separated from faces of the sensor electrode by spacings that depend on the rotational and translational movements of the sensor electrode relative to the electrode assembly. A signal generator (352) and address decoder (354) sequentially apply an alternating signal to the capacitor electrodes. The alternating signal is coupled to the closest associated faces of the sensor electrode to a degree dependent on the rotation- and translation-induced spacings. A controller (350) detects and processes each coupled signal voltage to determine a degree of deflection of the sensor electrode in the X-, Y-, Z-, roll-, pitch-, and yaw-axis directions.

Claims

1. A multiple axis data input apparatus, comprising:

a signal source generating an electrical signal;

an electrode assembly having multiple electrodes that are sequentially coupled to the electrical signal;

a sensor electrode having multiple faces, each face in proximity to an associated electrode of the electrode assembly;

a positioning means for orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received; and

a controller that receives and processes the signal amplitudes and generates spacing data related to the orientation-induced spacing between each face and its associated electrode.

2. The apparatus of claim 1 in which the predetermined number of axes is at least four, and the at least four axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

3. The apparatus of claim 1 in which the predetermined number of axes is six, and the six axes include an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

4. The apparatus of claim 1 in which the electrode assembly has mutually orthogonal electrodes, which together with the associated faces of the sensor electrode comprise mutually orthogonal capacitor electrode pairs positioned such that each capacitor electrode is separated from its associated sensor electrode face by the orientation-induced spacing.

5. The apparatus of claim 4 in which each of the electrodes has a major axial dimension that is substantially less than a corresponding major axial dimension of its associated sensor electrode face.

6. The apparatus of claim 1 in which the controller generates spatial orientation data for a Z-translation axis by employing a common-mode signal derived from the signal amplitudes employed to generate the spacing data for at least one of a roll-axis and a pitch-axis.

7. The apparatus of claim 1 in which the sensor electrode is formed from at least one of an electrically conductive material and a nonconductive material covered with an electrically conductive material.

8. The apparatus of claim 1 in which the sensor electrode is enclosed within an electrically conductive shield that decreases the sensitivity of the multiple faces to external electrical fields.

9. A multiple axis data input apparatus, comprising:

a signal source generating an electrical signal;

an electrode assembly having multiple electrodes coupled to the electrical signal;

a sensor electrode having multiple faces, each face in proximity to an associated electrode of the electrode assembly;

a positioning means for orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received;

a controller that processes the signal amplitudes with an amplifier, a peak detector, a filter, and an analog-to-digital converter to produce conditioned signal amplitudes; and

a microprocessor that processes the conditioned signal amplitudes to generate spacing data related to the orientation-induced spacing between each face and its associated electrode.

10. The apparatus of claim 9 in which the predetermined number of axes is at least four, and the at least four axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

11. The apparatus of claim 9 in which the predetermined number of axes is six, and the six axes include an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

12. The apparatus of claim 9 in which the signal source generates an alternating electrical signal that is sequentially electrically connected to the multiple electrodes.

13. The apparatus of claim 9 in which the electrode assembly has mutually orthogonal electrodes, which together with the associated faces of the sensor electrode comprise mutually orthogonal capacitor electrode pairs positioned such that each capacitor electrode is separated from its associated sensor electrode face by the orientation-induced spacing.

14. The apparatus of claim 13 in which each of the electrodes has a major axial dimension that is substantially less than a corresponding major axial dimension of its associated sensor electrode face.

15. The apparatus of claim 9 in which the microprocessor further processes the spacing data to compute spatial orientation data related to the orientation in each of the predetermined number of axes of the electrode assembly relative to the sensor electrode.

16. The apparatus of claim 9 in which the controller generates spatial orientation data for a Z-translation axis by employing a common-mode signal derived from the signal amplitudes employed to generate the spacing data for at least one of a roll-axis and a pitch-axis.

17. The apparatus of claim 9 in which the sensor electrode is formed from at least one of an electrically conductive material and a nonconductive material covered with an electrically conductive material.

18. The apparatus of claim 9 in which the sensor electrode is enclosed within an electrically conductive shield that decreases the sensitivity of the multiple faces to external electrical fields.

19. A multiple axis data input apparatus, comprising:

a signal source generating an electrical signal;

an electrode assembly having multiple electrodes coupled to the electrical signal;

a sensor electrode having multiple faces, each face in proximity to an associated electrode of the electrode assembly;

a positioning means for orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received, the positioning means including at least one of a compression spring, a flexible diaphragm, a bladder, a network of springs, and an elastomeric ring that acts to position the sensor electrode in an equilibrium position relative to the electrode assembly; and

a controller that receives and processes the signal amplitudes and generates spacing data related to the orientation-induced spacing between each face and its associated electrode.

20. The apparatus of claim 19 in which the predetermined number of axes is at least four, and the at least four axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

21. The apparatus of claim 19 in which the predetermined number of axes is six, and the six axes include an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

22. The apparatus of claim 19 in which the signal source generates an alternating electrical signal that is sequentially electrically connected to the multiple electrodes.

23. The apparatus of claim 19 in which the electrode assembly has mutually orthogonal electrodes, which together with the associated faces of the sensor electrode comprise mutually orthogonal capacitor electrode pairs positioned such that each capacitor electrode is separated from its associated sensor electrode face by the orientation-induced spacing.

24. The apparatus of claim 23 in which each of the electrodes has a major axial dimension that is substantially less than a corresponding major axial dimension of its associated sensor electrode face.

25. The apparatus of claim 19 in which the controller conditions the signal amplitudes with an amplifier, a peak detector, a filter, and an analog-to-digital converter, and a microprocessor processes the conditioned signal amplitudes to generate the spacing data.

26. The apparatus of claim 25 in which the microprocessor further processes the spacing data to compute spatial orientation data related to the orientation in each of the predetermined number of axes of the electrode assembly relative to the sensor electrode.

27. The apparatus of claim 19 in which the controller processes the signal amplitudes with a peak detector, a filter, and an analog-to-digital converter to generate the spacing data related to each of the signal amplitudes and further employs the spacing data to access a lookup table that returns information for generating spatial orientation data.

28. The apparatus of claim 19 in which the controller generates spatial orientation data for a Z-translation axis by employing a common-mode signal derived from the signal amplitudes employed to generate the spacing data for at least one of a roll-axis and a pitch-axis.

29. The apparatus of claim 19 in which the sensor electrode is formed from at least one of an electrically conductive material and a nonconductive material covered with an electrically conductive material.

30. The apparatus of claim 19 in which the sensor electrode is enclosed within an electrically conductive shield that decreases the sensitivity of the multiple faces to external electrical fields.

31. The apparatus of claim 19 in which the elastomeric ring imparts a biasing force to the sensor electrode that suspends the sensor electrode in an equilibrium position relative to the electrode assembly.

32. The apparatus of claim 31 in which the sensor electrode is coupled to the elastomeric ring by a rigid dome that facilitates positioning the sensor electrode in at least six predetermined axes relative to the electrode assembly.

33. The apparatus of claim 31 in which the biasing force is proportional to deformation of the elastomeric ring in at least one of a compression stress, a tension stress, and a shear stress.

34. The apparatus of claim 31 in which the elastomeric ring provides a substantially frictionless and a substantially damped positioning of the sensor electrode relative to the electrode assembly.

35. A multiple axis data input apparatus, comprising:

a signal source generating an electrical signal;

an electrode assembly having multiple electrodes coupled to the electrical signal;

a sensor electrode having multiple faces, each face in proximity to an associated electrode of the electrode assembly;

a positioning means for orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received, the positioning means including an elastomeric ring that suspends the sensor electrode relative to the electrode assembly and isolates the sensor electrode and the electrode assembly from at least one of dust, dirt, contaminants, and electric fields; and

a controller that receives and processes the signal amplitudes and generates spacing data related to the orientation-induced spacing between each face and its associated electrode.

36. The apparatus of claim 35 in which the predetermined number of axes is at least four, and the at least four axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

37. The apparatus of claim 35 in which the predetermined number of axes is six, and the six axes include an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

38. The apparatus of claim 35 in which the signal source generates an alternating electrical signal that is sequentially electrically connected to the multiple electrodes.

39. The apparatus of claim 35 in which the electrode assembly has mutually orthogonal electrodes, which together with the associated faces of the sensor electrode comprise mutually orthogonal capacitor electrode pairs positioned such that each capacitor electrode is separated from its associated sensor electrode face by the orientation-induced spacing.

40. The apparatus of claim 39 in which each of the electrodes has a major axial dimension that is substantially less than a corresponding major axial dimension of its associated sensor electrode face.

41. The apparatus of claim 35 in which the controller conditions the signal amplitudes with an amplifier, a peak detector, a filter, and an analog-to-digital converter, and a microprocessor processes the conditioned signal amplitudes to generate the spacing data.

42. The apparatus of claim 41 in which the microprocessor further processes the spacing data to compute spatial orientation data related to the orientation in each of the predetermined number of axes of the electrode assembly relative to the sensor electrode.

43. The apparatus of claim 35 in which the controller processes the signal amplitudes with a peak detector, a filter, and an analog-to-digital converter to generate the spacing data related to each of the signal amplitudes and further employs the spacing data to access a lookup table that returns information for generating spatial orientation data.

44. The apparatus of claim 35 in which the controller generates spatial orientation data for a Z-translation axis by employing a common-mode signal derived from the signal amplitudes employed to generate the spacing data for at least one of a roll-axis and a pitch-axis.

45. The apparatus of claim 35 in which the sensor electrode is formed from at least one of an electrically conductive material and a nonconductive material covered with an electrically conductive material.

46. The apparatus of claim 35 in which the sensor electrode is enclosed within an electrically conductive shield that decreases the sensitivity of the multiple faces to external electrical fields.

47. The apparatus of claim 35 in which the elastomeric ring acts to position the sensor electrode in an equilibrium position relative to the electrode assembly.

48. The apparatus of claim 35 in which the elastomeric ring imparts a biasing force to the sensor electrode that suspends the sensor electrode in an equilibrium position relative to the electrode assembly.

49. The apparatus of claim 48 in which the biasing force is proportional to deformation of the elastomeric ring in at least one of a compression stress, a tension stress, and a shear stress.

50. The apparatus of claim 35 in which the sensor electrode is coupled to the elastomeric ring by a rigid dome that facilitates positioning the sensor electrode in at least six predetermined axes relative to the electrode assembly.

51. The apparatus of claim 35 in which the elastomeric ring provides a substantially frictionless and a substantially damped positioning of the sensor electrode relative to the electrode assembly.

52. In a multiple axis data input apparatus, a method of generating spatial orientation data, comprising:

providing a source of an electrical signal;

coupling an electrode assembly having multiple electrodes to the electrical signal;

mounting a sensor electrode having at least three mutually orthogonal faces such that each face is in proximity to an associated electrode of the electrode assembly, the multiple electrodes and faces forming multiple capacitor electrodes positioned such that each capacitor electrode is separated from an associated face of the sensor electrode by the orientation-induced spacing;

orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received;

sampling the signal amplitudes sequentially;

detecting a peak amplitude of each of the sequentially sampled signal amplitudes;

converting the peak amplitude of each of the sequentially sampled signal amplitudes into spacing data; and

computing from the spacing data the spacial orientation data.

53. The method of claim 52 in which the predetermined number of axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

54. The method of claim 52 further including coupling capacitively the sensor electrode to the electrodes.

55. The method of claim 52 further including suspending the sensor electrode in an equilibrium position and providing a restoring force that acts to position the sensor electrode in the equilibrium position.

56. In a multiple axis data input apparatus, a method of generating spatial orientation data, comprising:

providing a source of an electrical signal;

coupling an electrode assembly having multiple electrodes to the electrical signal;

mounting a sensor electrode having multiple faces such that each face is in proximity to an associated electrode of the electrode assembly;

suspending the sensor electrode in an equilibrium position and providing a restoring force that acts to position the sensor electrode in the equilibrium position, the suspending carried out by at least one of a compression spring, a flexible diaphragm, a bladder, a network of springs, and an elastomeric ring;

orienting the sensor electrode in at least four predetermined axes relative to the electrode assembly such that each face receives an amount of the electrical signal that depends on an orientation-induced spacing between each face and its associated electrode and in which each face provides a signal amplitude in response to the amount of the electrical signal received;

processing the signal amplitudes to generate spacing data related to the orientation-induced spacing between each face and its associated electrode; and

computing from the spacing data the spacial orientation data.

57. The method of claim 56 in which the predetermined number of axes are selected from a group consisting of an X-translation axis, a Y-translation axis, a Z-translation axis, a roll-axis, a pitch-axis, and a yaw-axis.

58. The method of claim 56 further including coupling capacitively the sensor electrode to the electrodes.

59. The method of claim 56 in which the sensor electrode has at least three mutually orthogonal faces, and the multiple electrodes comprise multiple mutually orthogonal capacitor electrodes positioned such that each capacitor electrode is separated from an associated face of the sensor electrode by the orientation-induced spacing, the processing step further including:

sampling the signal amplitudes sequentially;

detecting a peak amplitude of each of the sequentially sampled signal amplitudes; and

converting the peak amplitude of each of the sequentially sampled signal amplitudes into the spacing data.

60. The method of claim 56 in which the elastomeric ring imparts the biasing force to the sensor electrode, the biasing force acting to suspend the sensor electrode in an equilibrium position relative to the electrode assembly.

61. The method of claim 60 in which the sensor electrode is mechanically coupled to the elastomeric ring by a rigid dome that facilitates orienting the sensor electrode in at least six predetermined axes relative to the electrode assembly.