Patent ID: 7671734
Filing Date: 2010-03-02
Classification: G01C,G01S

Abstract:
1. A footprint location system for determining a user's position by user's footprints, which include first footprints and second footprints, comprising: a first shoe comprising a first measuring unit and generating first footprints when both shoes touch the ground at the same time; a second shoe comprising a second measuring unit and generating second footprints when both shoes touch the ground at the same time; a vector measuring unit measuring displacement vectors between the first footprints and the second footprints based on coordinates provided by the first measuring unit and the second measuring unit; and a location calculation unit calculating the user's position by summing up all displacement vectors with reference to a starting point, wherein the first measuring unit has at least two ultrasonic infrared receivers and an orientation sensor, which provides a rotation angle .theta. in the global coordinate system; the second measuring unit has at least one ultrasonic infrared transmitter; and the first measuring unit, the second measuring unit and the orientation sensor measure coordinates and the rotation angle .theta., to calculate a displacement vector in a global coordinate system.