Patent ID: 6594617
Filing Date: 2003-07-15
Classification: G01C

Abstract:
A pedometer navigator system carried by a pedestrian having a left and right foot for calculating an SBPMS position displacement vector in a fixed navigational coordinate frame, having a north, east and down axis, comprising:an Euler Angle Measuring Subsystem (EAMS) having a right-handed or left-handed coordinate frame having an EAMS origin, the EAMS providing roll, pitch and azimuth Euler angle values for the right-handed or left-handed coordinate frame with respect to the north-east-down axes of the fixed navigation coordinate frame, a Short Baseline Position Measuring Subsystem (SBPMS) having an SBPMS coordinate frame having an SBPMS origin for measuring and providing a continuous series of time indexed left position vectors {right arrow over (&rgr;)}leftp and right position vectors {right arrow over (&rgr;)}rightp in SBPMS coordinate values characterizing the position of the left and right foot with respect to the SBPMS origin, the SBPMS coordinate frame being coupled to and in a fixed and predetermined alignment with the EAMS right-handed or left-handed coordinate frame, a computer means responsive to the roll, pitch and azimuth Euler angle values and the time indexed left and right position vectors for providing a first transition vector in fixed navigation coordinate frame values, characterizing the movement of the SBPMS origin for each interval that a left foot is stationary and the right foot is moving and a second transition vector in fixed navigation coordinate frame values characterizing the movement of the SBPMS origin for each interval that a right foot is stationary and the left foot is moving, the first and second transition vectors being added to form an SBPMS position displacement vector.