Providing Haptic Feedback On A Touch Surface

• US 20090322496A1
• Filed: 06/26/2008
• Published: 12/31/2009
• Est. Priority Date: 06/26/2008
• Status: Active Grant

• Current Assignee: Immersion Corporation
• Original Assignee: Immersion Corporation
• Inventors: da Costa, Henrique D.
• Granted Patent: US 8,174,372 B2
• Time in Patent Office: Days
• US Class Current: 340/407.2
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: H03K 17/96 Touch switches specially adapted for electronic time-pieces with no moving parts G04G21/08
• CPC Class Codes: H03K 2217/96062 with tactile or haptic feedback

Abstract

Systems and methods for providing haptic feedback to a touch surface are described herein. In one embodiment, among many, a layered structure comprises a first conducting layer electrically coupled to a first terminal of a power source and a second conducting layer electrically coupled to a second terminal of the power source. The layered structure also comprises a spacing layer electrically isolating the first conducting layer from the second conducting layer. Also, an actuation layer is positioned between the first conducting layer and the second conducting layer. The actuation layer includes a material that reacts to an electrical stimulus.

Claims

1. A haptic feedback system comprising:

a structure including a first conductive layer, a spacing layer, an actuation layer, and a second conductive layer, the actuation layer being sensitive to electrical current, at least one of the layers being sufficiently flexible to bend when a pressure is applied to the structure;

a power source electrically coupled to the first conductive layer and the second conductive layer;

wherein a normally open electrical circuit is formed from the structure and power source;

wherein, when an adequate pressure is applied to the structure, the electrical circuit is completed, allowing the current to flow through the structure and causing the actuation layer to provide a haptic effect.

2. The haptic feedback system of claim 1, further comprising a current sensor electrically coupled between the power source and one of the conductive layers, the current sensor configured to sense when the electrical circuit is completed.

3. The haptic feedback system of claim 2, further comprising a power source controller, wherein the current sensor indicates to the power source controller when the electrical circuit is completed.

4. The haptic feedback system of claim 3, wherein, in response to receiving an indication from the current sensor, the power source controller is configured to cause the power source to supply a predetermined current envelope to the structure.

5. The haptic feedback system of claim 4, wherein the predetermined current envelope includes a signal that decays to substantially zero after a predetermined length of time.

6. The haptic feedback system of claim 4, wherein the current sensor detects a magnitude of the current flowing through the electrical circuit and indicates the magnitude of the detected current to the power source controller, and wherein the power source controller selects one of a plurality of predetermined current envelopes to supply to the structure based on the magnitude of the detected current.

7. The haptic feedback system of claim 2, further comprising a distributing device and a controller, wherein the distributing device is electrically coupled between the power source and the first conductive layer and the controller is electrically coupled to each of the distributing device, power source, and current sensor.

8. The haptic feedback system of claim 7, wherein the first conductive layer comprises a first set of strips of conductive material and the second conductive layer comprises a second set of strips of conductive material, and wherein the first set of strips are positioned in a first direction and the second set of strips are positioned in a second direction that is substantially perpendicular to the first direction.

9. The haptic feedback system of claim 8, wherein the distributing device is configured to supply power from the power source to the first set of strips one strip at a time, and wherein the current sensor is configured to sense when current flows through one or more strips of the second set of strips.

10. The haptic feedback system of claim 9, wherein the controller is configured to cause the power source and distributing device to supply current to a strip of the first set of strips according to a predetermined decay envelope.

11. The haptic feedback system of claim 1, further comprising a position sensing device configured to determine where pressure is the applied to the structure.

12. The haptic feedback system of claim 11, further comprising a power source controller configured to control the output of the power source based on where the pressure is applied to the structure.

13. The haptic feedback system of claim 11, wherein the position sensing device includes a film-on-glass construction and the structure is positioned on top of the position sensing device.

14. The haptic feedback system of claim 11, wherein the position sensing device includes a film-on-film construction and is positioned on top of the structure.

15. The haptic feedback system of claim 1, wherein the power source is configured to supply a sinusoidal current to the structure.

16. A layered structure comprising:

a first conducting layer electrically coupled to a first terminal of a power source;

a second conducting layer electrically coupled to a second terminal of the power source;

a spacing layer electrically isolating the first conducting layer from the second conducting layer; and

an actuation layer positioned between the first conducting layer and the second conducting layer;

wherein the actuation layer includes a material that reacts to an electrical stimulus.

17. The layered structure of claim 16, wherein the first conducting layer is sufficiently flexible such that a pressure applied to the first conducting layer causes the first conducting layer to come into contact with the actuation layer.

18. The layered structure of claim 16, wherein the actuation layer is positioned adjacent to the second conducting layer and is electrically isolated from the first conducting layer by the spacing layer.

19. The layered structure of claim 16, wherein the actuation layer is positioned adjacent to the first conducting layer and is electrically isolated from the second conducting layer by the spacing layer.

20. The layered structure of claim 16, further comprising a first protective layer formed adjacent to the first conducting layer to protect the first conducting layer.

21. The layered structure of claim 20, further comprising a second protective layer formed adjacent to the second conducting layer to protect the second conducting layer.

22. The layered structure of claim 21, wherein the second protective layer provides support for the layered structure.

23. The layered structure of claim 16, further comprising a third conductive layer formed between the first conductive layer and the second conductive layer.

24. The layered structure of claim 23, wherein the third conductive layer includes a first set of regions that are electrically insulated from each other and the actuation layer includes a second set of regions that are electrically insulated from each other, and wherein a first pattern formed by the first set of regions corresponds to a second pattern formed by the second set of regions.

25. The layered structure of claim 23, wherein the third conductive layer is formed between the spacing layer and actuation layer.

26. The layered structure of claim 25, wherein the third conductive layer includes a plurality of regions that are electrically insulated from each other.

27. The layered structure of claim 25, wherein at least one of the third conductive layer and the actuation layer includes a plurality of regions that are electrically insulated from each other, the plurality of regions formed in an array corresponding to locations where a user can apply pressure.

28. The layered structure of claim 16, wherein the actuation layer includes a plurality of regions that are electrically insulated from each other.

29. The layered structure of claim 16, wherein the spacing layer causes a circuit formed by the layered structure and the power source to be a normally open circuit, the circuit being open by the spacing layer forming a gap in the circuit.

30. The layered structure of claim 29, wherein one or more of the layers are sufficiently flexible such that a pressure applied to the one or more layers causes the circuit to be complete by bridging the gap in the circuit.

31. The layered structure of claim 16, further comprising a plurality of spacing layers and a plurality of actuation layers.

32. A method comprising:

providing a layered structure including first and second conductive layers electrically coupled to a power source, the layered structure further including an electrically-sensitive actuation layer, the layered structure being configured as a normally open circuit where two layers of the layered structure are normally separated by a spacing layer;

allowing sufficient pressure to be applied to the layered structure to bring the two layers normally separated by the spacing layer into contact with each other; and

conducting current through the actuation layer when sufficient pressure is applied.

33. The method of claim 32, wherein the layered structure further comprises a third conductive layer.

34. The method of claim 33, wherein at least one of the actuation layer and the third conductive layer includes a plurality of regions that are electrically insulated from each other.

35. The method of claim 32, wherein the layered structure further comprises one or more protective layers.

36. The method of claim 32, wherein the pressure is applied by a user.

37. The method of claim 36, wherein conducting current causes the actuation layer to provide a haptic effect to the user.

38. The method of claim 32, wherein conducting current includes conducting an alternating current.

39. The method of claim 38, wherein conducting the alternating current through the actuation layer causes at least a portion of the actuation layer to vibrate.

40. The method of claim 32, further comprising:

sensing when the layered structure is in a closed circuit state; and

adjusting the output of the power source to control the activation characteristics of the actuation layer.

41. The method of claim 40, wherein adjusting the output of the power source includes applying a predetermined decaying envelope to the output, the decaying envelope having a magnitude that drops to substantially zero after a predetermined length of time.

42. The method of claim 32, further comprising:

sensing when the layered structure is in a closed circuit state;

sensing a location where pressure is applied to the layered structure;

determining a stimulus envelope based on the location where the pressure was applied; and

adjusting the output of the power source to control the stimulation characteristics of the actuation layer based on the stimulus envelope.

43. The method of claim 42, wherein sensing location where pressure is applied further comprises:

applying input signals one at a time to a plurality of electrically isolated strips of the first conductive layer; and

sensing output signals from one or more of a plurality of electrically isolated strips of the second conductive layer;

wherein the strips of the first conductive layer are positioned in a first direction and the strips of the second conductive layer are positioned in a second direction that is substantially perpendicular to the first direction; and

wherein the combination of a first location of the stimulated strip of the first conductive layer and a location of the one or more strips of the second conductive layer where output signals are sensed is indicative of a general location where pressure is applied.