Sensor on moving component of transducer

• US 10,142,754 B2
• Filed: 02/21/2017
• Issued: 11/27/2018
• Est. Priority Date: 02/22/2016
• Status: Active Grant

• Current Assignee: Sonos, Inc.
• Original Assignee: Sonos, Inc.
• Inventors: Sheen, Timothy W., Jarvis, Simon, Kadri, Romi, Chen, Yean-Nian Willy
• Primary Examiner(s): Patel, Yogeshkumar
• Application Number:
  US15/438,744
• Publication Number:
  US 20170245054A1
• Time in Patent Office: 644 Days
• Field of Search: 381 74, 381162, 381405, 367140, 702104
• CPC Class Codes: H04R 2227/003 Digital PA systems using, e.g. LAN or internet
• CPC Class Codes: H04R 2227/005 Audio distribution systems for home, i.e. multi-room use
• CPC Class Codes: H04R 2227/007 Electronic adaptation of audio signals to reverberation of the listening space for PA
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F
• CPC Class Codes: H04R 29/003 of the moving-coil type
• CPC Class Codes: H04R 29/007 for public address systems public address systems per se H04R27/00
• CPC Class Codes: H04R 3/007 Protection circuits for transducers
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04R 9/046 Construction
• CPC Class Codes: H04S 7/305 Electronic adaptation of stereophonic audio signals to reverberation of the listening space H04S7/301 takes precedence
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

A signal from a sensor may be received indicative of an acceleration of a moving component of a transducer at a location where the sensor is mounted. A position the moving component may be determined based on the acceleration. The position of the moving component may be compared with a reference to output a measure of distortion associated with the transducer. Nonlinearities in audio output by the transducer may be corrected based on the measure of distortion.

Claims

1. A device comprising:

a transducer having a movable component;

a sensor mounted on the movable component of the transducer;

a processor; and

memory storing computer instructions that, when executed by the processor, cause the processor to perform operations comprising;

receive a signal from the sensor indicative of an acceleration of the movable component at a location where the sensor is mounted;

determine a position of the movable component based on the acceleration at a first time;

calculate a difference between the position of the movable component at the first time and a predicted position of the movable component at the first time to output a measure of distortion associated with the transducer, wherein the predicted position of the movable component at the first time is based on a model of displacement of the movable component, and wherein the predicted position of the movable component at the first time is different than a predicted position of the movable component at a second time, and wherein the predicted position of the movable component at the second time is based on the model of displacement of the movable component; and

cause nonlinearities in audio output by the transducer to be reduced based on the measure of distortion.

2. The device of claim 1, wherein the measure of distortion is intermodulation distortion of the transducer.

3. The device of claim 1, wherein the sensor is a force sensor.

4. The device of claim 1, wherein the sensor is mounted on a voice coil former, dust cap, cone, or surround of the transducer.

5. The device of claim 1, wherein a counterweight is added to a voice coil former, cone or surround of the transducer when the sensor is mounted on the voice coil former, cone, or surround.

6. The device of claim 1, wherein determining a position the movable component based on the acceleration comprises integrating the signal from the sensor indicative of the acceleration over a period of time.

7. The device of claim 1, further comprising computer instructions for updating, based on the measure of distortion, the model which outputs a measure of expected distortion of the transducer;

and wherein correcting for nonlinearities in audio output by the transducer based on a second signal input into the transducer and the measure of distortion comprises correcting for nonlinearities in audio output by the transducer based on a third signal input into the transducer and the measure of expected distortion.

8. The device of claim 1, further comprising computer instructions for limiting a maximum displacement of the movable component of the transducer based on the position of the movable component.

9. A method comprising:

receiving a signal from a sensor mounted on a movable component of a transducer, the signal indicative of an acceleration of the movable component of the transducer at a location where the sensor is mounted;

determining a position of the movable component based on the acceleration at a first time;

calculating a difference between the position of the movable component at the first time and a predicted position of the movable component at the first time to output a measure of distortion associated with the transducer, wherein the predicted position of the movable component at the first time is based on a model of displacement of the movable component, and wherein the predicted position of the movable component at the first time is different than a predicted position of the movable component at a second time, and wherein the predicted position of the movable component at the second time is based on the model of displacement of the movable component; and

cause nonlinearities in audio output by the transducer to be corrected based on the measure of distortion.

10. The method of claim 9, wherein the measure of distortion is intermodulation distortion of the transducer.

11. The method of claim 9, wherein the sensor is a force sensor.

12. The method of claim 9, wherein the sensor is mounted on a voice coil former, dust cap, cone, or surround of the transducer.

13. The method of claim 9, wherein a counterweight is added to a voice coil former, cone or surround of the transducer when the sensor is mounted on the voice coil former, cone, or surround.

14. The method of claim 9, wherein determining a position of the movable component based on the acceleration comprises integrating the signal from the sensor indicative of the acceleration of the movable component over a period of time.

15. The method of claim 9, further comprising updating based the measure of distortion the model which outputs a measure of an expected distortion of the transducer;

and wherein correcting for nonlinearities in audio output by the transducer based on a second signal input into the transducer and the measure of distortion comprises correcting for nonlinearities in audio output by the transducer based on a third signal input into the transducer and measure of the expected distortion.

16. The method of claim 9, further comprising limiting a maximum displacement of the movable component of the transducer based on the position of the movable component.

17. A tangible non-transitory computer readable storage medium including memory storing computer instructions that, when executed by a processor, cause the processor to implement a method comprising:

receiving a signal from a sensor mounted on a movable component of a transducer, the signal indicative of an acceleration of the movable component of the transducer at a location where the sensor is mounted;

determining a position of the movable component based on the acceleration at a first time;

calculating a difference between the position of the movable component at the first time and a predicted position of the movable component at the first time to output a measure of distortion associated with the transducer, wherein the predicted position of the movable component at the first time is based on a model of displacement of the movable component, and wherein the predicted position of the movable component at the first time is different than a predicted position of the movable component at a second time, and wherein the predicted position of the movable component at the second time is based on the model of displacement of the movable component; and

cause nonlinearities in audio output by the transducer to be corrected based on the measure of distortion.

18. The tangible non-transitory computer readable storage medium of claim 17, further comprising computer instructions to obtain acoustics of an environment in which the transducer is located;

and apply the acoustics a voice input received at a microphone.