Computer input device with inertial instruments

• US 9,098,122 B2
• Filed: 12/12/2007
• Issued: 08/04/2015
• Est. Priority Date: 12/12/2007
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Weinberg, Marc S., Larsen, Robert A., Rasmussen, Scott A.
• Primary Examiner(s): Moon, Seokyun
• Application Number:
  US11/955,244
• Publication Number:
  US 20090153482A1
• Time in Patent Office: 2,792 Days
• Field of Search: 345/156, 345/163
• US Class Current: 1/1
• CPC Class Codes: G06F 3/03 Arrangements for converting the position or the displacement of a member into a coded form
• CPC Class Codes: G06F 3/03543 Mice or pucks G06F3/03541 takes precedence

Abstract

A computer input device includes, in one embodiment, at least two accelerometers, at least two gyroscopes, and a processor within a housing. Signals from the accelerometers and the gyroscopes are utilized to determine the relative motion of the computer input device.

Claims

1. A computer input device, comprising:

a housing for movement over a substantially two-dimensional surface;

a sensor unit, disposed within the housing, comprising a plurality of inertial sensors, at least two of the inertial sensors being accelerometers and at least two of the inertial sensors being gyroscopes; and

a processor for determining relative motion of the computer input device utilizing signals from the accelerometers and the gyroscopes, the signals from the gyroscopes indicating rotation of the computer input device about an axis perpendicular to the direction of gravity due to non-uniformity or tilt of the substantially two-dimensional surface as the computer input device is moved thereover, and the signals from the accelerometers indicating acceleration of the computer input device;

wherein the processor is configured to utilize the signals from the gyroscopes to correct the signals from the accelerometers for acceleration error introduced by gravity due to the non-uniformity or tilt of the substantially two-dimensional surface as the computer input device is moved thereover.

2. The computer input device of claim 1, further comprising an optical sensor for sensing relative motion of the computer input device.

3. The computer input device of claim 1, further comprising a digital filter for combining the signals from the accelerometers and the gyroscopes.

4. The computer input device of claim 3, wherein the digital filter comprises a Kalman filter.

5. The computer input device of claim 1, further comprising means for transmitting, to a computing device, data indicative of the relative motion of the computer input device.

6. The computer input device of claim 1, further comprising:

at least one user-operable button disposed on the housing; and

means for transmitting, to a computing device, data indicative of the button'"'"'s operation.

7. The computer input device of claim 6, wherein the data indicative of the button'"'"'s operation is utilized at least in part to indicate that the computer input d is substantially motionless.

21. The computer input device of claim 1, further comprising:

circuitry for calibrating at least one of the inertial sensors by updating a bias of the inertial sensor based on a signal value received directly therefrom when the computer input device is determined to be motionless.

22. The computer input device of claim 21, wherein the computer input device is determined to be motionless when either (a) a velocity of the computer input device is below a velocity threshold and an acceleration of the computer input device is below an acceleration threshold or (b) a user-operable button disposed on the computer input device is depressed.

23. The computer input device of claim 21, wherein the updated bias comprises a component of at least one of the non-uniformity or tilt of the substantially two dimensional surface.

8. A method of fabricating a computer input device, the method comprising:

providing a housing; and

disposing, within the housing, (i) a sensor unit comprising a plurality of inertial sensors, at least two of the inertial sensors being accelerometers and at least two of the inertial sensors being gyroscopes, and (ii) circuitry, responsive to the sensor unit, for determining movement of the housing over a substantially two-dimensional surface by, at least in part, utilizing signals from the accelerometers and gyroscopes, the signals from the accelerometers indicating acceleration of the housing and the signals from the gyroscopes indicating rotation of the housing about an axis perpendicular to the direction of gravity due to non-uniformity or tilt of the substantially two-dimensional surface as the housing is moved thereover, and correcting, based on the signals from the gyroscopes, the signals from the accelerometers for acceleration error introduced by gravity due to the non-uniformity or tilt of the substantially two-dimensional surface as the housing is moved thereover.

9. The method of claim 8, further comprising providing within the housing an optical sensor for sensing relative motion of the computer input device.

10. The method of claim 8, further comprising providing within the housing means for transmitting, to a computing device, data indicative of the movement of the housing.

11. The method of claim 8, further comprising encoding into the circuitry a digital filter to combine signals from the accelerometers and the gyroscopes.

12. The method of claim 11, wherein the digital filter comprises a Kalman filter.

13. A method of determining relative motion of a computer input device, the method comprising:

moving a housing over a substantially two-dimensional surface, the housing comprising a plurality of inertial sensors and a processor, at least two of the inertial sensors being accelerometers and at least two of the inertial sensors being gyroscopes;

calculating the relative motion of the housing utilizing signals from the accelerometers and the gyroscopes generated in response to the motion of the housing, the signals from the gyroscopes indicating rotation of the housing about an axis perpendicular to the direction of gravity due to movement of the housing over the substantially two-dimensional surface and the signals from the accelerometers indicating acceleration of the housing; and

correcting, based on the signals from the gyroscopes, the signals from the accelerometers for acceleration error introduced by gravity due to non-uniformity or tilt of the substantially two-dimensional surface as the housing is moved thereover.

14. The method of claim 13, wherein the substantially two dimensional surface is non-uniform.

15. The method of claim 13, wherein the substantially two dimensional surface is tilted.

16. The method of claim 13, wherein calculating the relative motion comprises combining the signals generated by the accelerometers and the gyroscopes.

17. The method of claim 16, wherein the combining comprises utilizing a Kalman filter.

18. The method of claim 13, further comprising transmitting the relative motion of the housing to a computing device.

24. The method of claim 13, further comprising:

calibrating at least one of the inertial sensors by updating a bias of the inertial sensor based on a signal value received directly therefrom when the housing is determined to be motionless.

25. The method of claim 24, wherein the housing is determined to be motionless when either (a) a velocity of the housing is below a velocity threshold and an acceleration of the housing is below an acceleration threshold or (b) a user-operable button disposed on the housing is depressed.

26. The method of claim 24, wherein the updated bias comprises a component of at least one of the non-uniformity or tilt of the substantially two-dimensional surface.

19. A computer input device, con sing:

a housing for movement over a substantially two-dimensional surface;

means, disposed within the housing, for sensing acceleration of the computer input device;

means, disposed within the housing, for sensing angular motion with regard to an axis perpendicular to the direction of gravity due to at least one of non-uniformity or tilt of the substantially two-dimensional surface as the housing is moved thereover;

means for correcting for an acceleration error introduced by gravity due to the non-uniformity or tilt of the substantially two-dimensional surface as the housing is moved thereover; and

means, disposed within the housing, for calculating relative motion of the computer input device utilizing signals from (i) the means for sensing acceleration, (ii) the means for sensing angular motion, and (iii) the means for correcting.

20. A computing device, comprising:

a processor;

a display electrically connected and responsive to the processor; and

a computer input device in communication with the processor, comprising;

a housing for movement over a substantially two-dimensional surface,

a sensor unit, disposed within the housing, comprising a plurality of inertial sensors, at least two of the inertial sensors being accelerometers and at least two of the inertial sensors being gyroscopes, and

circuitry for determining relative motion of the computer input device utilizing signals from the accelerometers and the gyroscopes, the signals from the gyroscopes indicating rotation of the computer input device about an axis perpendicular to the direction of gravity due to non-uniformity or tilt of the substantially two-dimensional surface as the computer input device is moved thereover and the signals from the accelerometers indicating acceleration of the computer input device,

wherein the circuitry is configured to utilize the signals from the gyroscopes to correct the signals from the accelerometers for an acceleration error introduced by gravity due to the non-uniformity or tilt of the substantially two-dimensional surface as the computer input device is moved thereover.