In-situ monitoring, calibration, and testing of a haptic actuator

Patent metadata

Field	Value
Publication number	US-11662821-B2
Application number	US-202016850904-A
Country	US
Kind code	B2
Filing date	Apr 16, 2020
Priority date	Apr 16, 2020
Publication date	May 30, 2023
Grant date	May 30, 2023

Abstract

A method may include measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, correlating a relationship between the mechanical parameter and the electrical parameter, and calibrating the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

First claim

What is claimed is:

1. A method comprising:
measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, wherein the electrical parameter comprises a back-electromotive force associated with the electromagnetic load;
measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, wherein the mechanical parameter comprises a velocity of the host device;
correlating a relationship between the mechanical parameter and the electrical parameter; and
calibrating the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

2. The method of claim 1 , wherein correlating the relationship comprises calculating based on the back-electromotive and the velocity, for each of a plurality of velocities of the host device, a respective magnetic force factor at such velocity.

3. The method of claim 2 , wherein calibrating the electromagnetic load comprises calibrating the electromagnetic load based on the plurality of velocities of the host device and their respective magnetic force factors at each such velocity.

4. The method of claim 2 , wherein calibrating the electromagnetic load comprises filtering the driving signal, when actively driving the electromagnetic load, with a filter having a response based on the plurality of velocities of the host device and their respective magnetic force factors at each such velocity.

5. The method of claim 1 , further comprising recording the relationship and storing the relationship in computer-readable media.

6. The method of claim 5 , wherein calibrating comprises retrieving the relationship from the computer-readable media and calibrating based on the relationship as retrieved from the computer-readable media.

7. The method of claim 1 , wherein the mechanical motion is caused by normal use of the host device during its use by an end user of the host device.

8. The method of claim 1 , wherein the mechanical motion is caused by a mechanical exciter during post-production calibration of the host device.

9. The method of claim 1 , wherein the electromagnetic load comprises a haptic transducer.

10. A system comprising:
a first input for measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, wherein the electrical parameter comprises a back-electromotive force associated with the electromagnetic load;
a second input for measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, wherein the mechanical parameter comprises a velocity of the host device; and
a processing subsystem configured to:
correlate a relationship between the mechanical parameter and the electrical parameter; and
calibrate the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

11. The system of claim 10 , wherein correlating the relationship comprises calculating based on the back-electromotive and the velocity, for each of a plurality of velocities of the host device, a respective magnetic force factor at such velocity.

12. The system of claim 11 , wherein calibrating the electromagnetic load comprises calibrating the electromagnetic load based on the plurality of velocities of the host device and their respective magnetic force factors at each such velocity.

13. The system of claim 11 , wherein calibrating the electromagnetic load comprises filtering the driving signal, when actively driving the electromagnetic load, with a filter having a response based on the plurality of velocities of the host device and their respective magnetic force factors at each such velocity.

14. The system of claim 10 , wherein the processing subsystem is further configured to record the relationship and store the relationship in computer-readable media.

15. The system of claim 14 , wherein calibrating comprises retrieving the relationship from the computer-readable media and calibrating based on the relationship as retrieved from the computer-readable media.

16. The system of claim 10 , wherein the mechanical motion is caused by normal use of the host device during its use by an end user of the host device.

17. The system of claim 10 , wherein the mechanical motion is caused by a mechanical exciter during post-production calibration of the host device.

18. The system of claim 10 , wherein the electromagnetic load comprises a haptic transducer.

19. A host device comprising:
an electromagnetic load; and
a processing subsystem configured to:
measure an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, wherein the electrical parameter comprises a back-electromotive force associated with the electromagnetic load;
measure a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, wherein the mechanical parameter comprises a velocity of the host device;
correlate a relationship between the mechanical parameter and the electrical parameter; and
calibrate the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

Assignees

• Cirrus Logic Int Semiconductor Ltd
• Cirrus Logic Inc

Inventors

• Khenkin Aleksey
• Yan Jun
• Janko Marco
• Mcknight Michael

Classifications

• B06B1/0261 Primary

  taken from a transducer or electrode connected to the driving transducer · CPC title

• H02N1/006

  of the gap-closing type (H02N1/004 takes precedence) · CPC title

• H10N30/20

  with electrical input and mechanical output, e.g. functioning as actuators or vibrators · CPC title

• G06F3/016 Primary

  Input arrangements with force or tactile feedback as computer generated output to the user · CPC title

• H02N2/142

  Small signal circuits; Means for controlling position or derived quantities, e.g. speed, torque, starting, stopping, reversing · CPC title