Contact tracking and identification module for touch sensing

  • US 8,482,533 B2
  • Filed: 06/05/2009
  • Issued: 07/09/2013
  • Est. Priority Date: 01/26/1998
  • Status: Expired due to Term
  • ×
    • Pin Icon | RPX Insight
    • Pin
First Claim
Patent Images

1. A method of generating a control signal of a computing system including a touch sensitive surface, the method comprising:

  • tracking a path of each contact of a set of one or more contacts, each contact corresponding to a touch object on or near the surface;

    determining motion information of the set of contacts based on the tracking;

    determining a liftoff from the touch sensitive surface of one or more contacts of the set based on the tracking;

    determining a dominant component of motion of the set of contacts based on the motion information prior to the liftoff, the dominant component of motion including one of translation, rotation, and scaling;

    determining a first motion of the one or more contacts determined to have lifted off based on the motion information prior to the liftoff, including determining a weighted average velocity of the dominant component of motion prior to the liftoff;

    determining whether the first motion is greater than a predetermined threshold; and

    generating, based on the determination of whether the first motion is greater than the predetermined threshold, a post-liftoff control signal based on the dominant component of motion.

View all claims