Haptic feedback generation based on resonant frequency

• US 7,843,277 B2
• Filed: 12/16/2008
• Issued: 11/30/2010
• Est. Priority Date: 12/16/2008
• Status: Active Grant

• Current Assignee: Immersion Corporation
• Original Assignee: Immersion Corporation
• Inventors: Gregorio, Pedro, Grant, Danny A., Meunier, Eric, Favreau, Patrice
• Primary Examiner(s): Chang; Joseph
• Application Number:
  US12/336,231
• Publication Number:
  US 20100153845A1
• Time in Patent Office: 714 Days
• Field of Search: 331/65, 331/35, 331/116.R, 331/116.M, 331/154, 715/702, 310/318, 310/37, 345/156, 345/173
• US Class Current: 331/65
• CPC Class Codes: G01H 11/06 by electric means
• CPC Class Codes: G06F 2203/013 Force feedback applied to a game
• 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: G09G 3/296 Driving circuits for producing the waveforms applied to the driving electrodes
• CPC Class Codes: H02N 2/14 Drive circuits; Control arrangements or methods

Abstract

A system that generates a haptic effect generates a drive cycle signal that includes a drive period and a monitoring period. The drive period includes a plurality of drive pulses that are based on the haptic effect. The system applies the drive pulses to a resonant actuator during the drive period and receives a signal from the resonant actuator that corresponds to the position of a mass in the actuator during the monitoring period.

Claims

1. A method of generating a haptic effect comprising:

generating a drive cycle signal that comprises a drive period and a monitoring period, wherein the drive period comprises a plurality of drive pulses that are based on the haptic effect;

applying the drive pulses to a resonant actuator during the drive period, wherein the resonant actuator comprises a mass; and

receiving a signal that comprises a position of the mass from the resonant actuator during the monitoring period.

2. The method of claim 1, further comprising:

modifying an amplitude of one of the drive pulses in response to the signal.

3. The method of claim 2, wherein the signal is a back electromagnetic field (EMF).

4. The method of claim 3, wherein the amplitude is modified based on a derivative of the back EMF.

5. The method of claim 2, wherein the drive pulse is out of phase with a resonant actuator oscillation.

6. The method of claim 2, wherein the drive pulse is in phase with a resonant actuator oscillation.

7. The method of claim 1, further comprising:

determining a resonant frequency of the resonant actuator during the monitoring period.

8. The method of claim 1, wherein the haptic effect is a vibrotactile haptic effect.

9. The method of claim 1, wherein the resonant actuator is a linear resonant actuator.

10. The method of claim 1, wherein the signal is generated by a sense coil in proximity to the mass.

11. A haptic effect enabled system comprising:

a resonant actuator that comprises a mass;

circuitry coupled to the resonant actuator, wherein the circuitry is adapted to generate a drive cycle signal that comprises a drive period and a monitoring period, wherein the drive period comprises a plurality of drive pulses that are based on a haptic effect;

wherein the circuitry is adapted to apply the drive pulses to a resonant actuator during the drive period, and receive a signal that comprises a position of the mass from the resonant actuator during the monitoring period.

12. The system of claim 11, the circuitry further adapted to modify an amplitude of one of the drive pulses in response to the signal.

13. The system of claim 12, wherein the signal is a back electromagnetic field (EMF).

14. The system of claim 13, wherein the amplitude is modified based on a derivative of the back EMF.

15. The system of claim 12, wherein the drive pulse is out of phase with a resonant actuator oscillation.

16. The system of claim 12, wherein the drive pulse is in phase with a resonant actuator oscillation.

17. The system of claim 11, the circuitry further adapted to determine a resonant frequency of the resonant actuator during the monitoring period.

18. The system of claim 11, wherein the haptic effect is a vibrotactile haptic effect.

19. The system of claim 11, wherein the resonant actuator is a linear resonant actuator.

20. The system of claim 11, wherein the signal is generated by a sense coil in proximity to the mass.

21. The system of claim 11, wherein the circuitry comprises a processor and instructions stored on a computer readable media.

22. A system for generating a haptic effect comprising:

means for generating a drive cycle signal that comprises a drive period and a monitoring period, wherein the drive period comprises a plurality of drive pulses that are based on the haptic effect;

means for applying the drive pulses to a resonant actuator during the drive period, wherein the resonant actuator comprises a mass; and

means for receiving a signal that comprises a position of the mass from the resonant actuator during the monitoring period.

23. A computer readable media having instructions stored thereon that, when executed by a processor, causes the processor to generate a haptic effect, the instructions comprising:

generating a drive cycle signal that comprises a drive period and a monitoring period, wherein the drive period comprises a plurality of drive pulses that are based on the haptic effect;

applying the drive pulses to a resonant actuator during the drive period, wherein the resonant actuator comprises a mass; and

receiving a signal that comprises a position of the mass from the resonant actuator during the monitoring period.

24. The computer readable media of claim 23, the instructions further comprising:

modifying an amplitude of one of the drive pulses in response to the signal.

25. The computer readable media of claim 23, wherein the signal is a back electromagnetic field (EMF).