Gesture Recognition

• US 20090273571A1
• Filed: 10/20/2008
• Published: 11/05/2009
• Est. Priority Date: 05/01/2008
• Status: Active Grant

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Bowens, Alan
• Granted Patent: US 8,526,767 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A state machine gesture recognition algorithm for interpreting streams of coordinates received from a touch sensor. The gesture recognition code can be written in a high level language such as C and then compiled and embedded in a microcontroller chip, or CPU chip as desired. The gesture recognition code can be loaded into the same chip that interprets the touch signals from the touch sensor and generates the time series data, e.g. a microcontroller, or other programmable logic device such as a field programmable gate array.

Claims

1. A touch sensor device comprising:

a sensor having a sensitive area extending in at least one-dimension and arranged to output sense signals responsive to proximity of an object to the sensitive area;

a position processing unit operable to calculate positions of interactions with the sensitive area from an analysis of the sense signals, and output a time series of data indicative of the interaction positions on the sensor, and thus touches; and

a gesture processing unit operable to analyze the time series data to distinguish one or more gesture inputs therefrom, wherein the gesture processing unit is coded with gesture recognition code comprising a plurality of linked state modules.

2. The device of claim 1, wherein the plurality of state modules includes an idle state module and a plurality of gesture interpretation state modules, wherein the idle state module is entered at the start of operation, and is returnable to from at least some of the gesture interpretation state modules.

3. The device of claim 2, wherein the plurality of gesture interpretation state modules includes a touch state module for single touches, and wherein, responsive to a touch, the idle state passes control to the touch state.

4. The device of claim 2, wherein, the plurality of gesture interpretation state modules includes at least one multitouch state module operable to process multiple simultaneous touches, and wherein the gesture processing unit is operable to pass control to the appropriate touch state module based on the number of simultaneous touches defined by the time series data at the time.

5. The device of claim 4, wherein there is a multitouch state module for each of two simultaneous touches and three simultaneous touches.

6. The device of claim 2, wherein the plurality of gesture interpretation state modules includes a press state module to which control can pass from a touch state module if a touch of a duration longer than a threshold duration is sensed in the touch state module.

7. The device of claim 6, wherein the press state is a superstate comprising multiple sub-states to distinguish between different durations of press.

8. The device of claim 2, wherein the plurality of gesture interpretation state modules includes a plurality of state modules operable to recognize motion related gestures derived from one or more moving touches.

9. The device of claim 1, wherein the gesture recognition code is configured to recognize gestures having up to N simultaneous touches, wherein N is at least 2, and comprises N single-touch state machines operable to recognize only single touch gestures, and N-1 multi-touch state machines each operable to recognize only n-touch gestures, wherein n=2 to N.

10. The device of claim 1, wherein the position processing unit and the gesture processing unit are accommodated in, and run on, a single integrated circuit.

11. The device of claim 1, wherein the position processing unit is accommodated in, and runs on, a first integrated circuit, and the gesture processing unit is accommodated in, and runs on, one or more separate integrated circuits.

12. A method of recognizing gestures from a time series of touch data comprising coordinates of interaction positions on a touch sensor, the method comprising:

receiving touch coordinates labeled with, or ordered by, time;

analyzing the touch coordinates in a state machine comprising a plurality of linked state modules to recognize any one of a plurality of defined gestures therefrom; and

outputting the recognized gestures.

13. A single integrated circuit having a memory on which is loaded the state machine of claim 12 and which is operable to carry out the method of claim 12.

14. A computer having a memory on which is loaded the state machine of claim 12 and which is operable to carry out the method of claim 12.