ESTIMATING THE GRAVITY VECTOR IN A WORLD COORDINATE SYSTEM USING AN ACCELEROMETER IN A MOBILE DEVICE

摘要

The accelerometer is located in a mobile device is used to estimate the gravity vector on the target plane in the world coordinate system. Accelerometers and perform a number of measurements, each measurement is the mobile device is held fixedly on the target plane, facing the flat portion of the surface of the mobile device to the target plane is taken as a contact. The average of the measurements is calculated. A rotation transformation between the coordinate system and the coordinate system of the accelerometer of the mobile device is retrieved from the memory of the mobile device, wherein the coordinate system of the mobile device is aligned with the surface of the mobile device. The rotational transformation to obtain a weight vector estimated by the world coordinate system defined by the target plane is applied to the averaged measurements. ;