US 6,983,219 B2
Method and arrangement for determining movement
Jani Mäntyjärvi, Kempele (Finland); and Panu Korpipää, Oulu (Finland)
Assigned to Nokia Corporation, Espoo (Finland)
Filed on Jun. 27, 2002, as Appl. No. 10/186,257.
Claims priority of application No. 20011408 (FI), filed on Jun. 29, 2001.
Prior Publication US 2003/0109258 A1, Jun. 12, 2003
Int. Cl. G01C 19/00 (2006.01)
U.S. Cl. 702—153 24 Claims
OG exemplary drawing
 
1. A method for determining the movement of a device, in which method the acceleration of the device is measured at least in three different directions to provide a three-dimensional measurement, the method comprising
generating acceleration signals parallel to three orthogonal axes, which are in a known orientation to the device;
generating average signals of the acceleration signals parallel to the different axes;
defining tilt angles of the device in relation to the direction of gravity by means of the average signals;
generating acceleration change signals by removing the average signals from their respective acceleration signals parallel to the different axes;
forming a component of the acceleration change of the device by means of the acceleration change signals and the tilt angles of the device, which component is parallel to gravity and independent of the position of the device.