Orientation Of A Triaxial Accelerometer Using A Homogeneous Transformation Matrix And Kalman Filters

The evolution in the development of manufacturing techniques of electronic components, including accelerometers, has allowed access to a new field of research and applications in consumer electronics. The aim of this work is to present a method for aligning triaxial accelerometers, finding the parameters of the rotation, the translation and the scale of the homogeneous transformation matrix. In principle, it is necessary to acquire six points to build the frame of reference of the accelerometer and ensure the consistency of the measurements, in order to check the angle between the axis and the magnitude. Subsequently, using spatial geometry, the intersection of the system of reference is estimated, to determine the extent of translation in the homogeneous transformation matrix. In a further step, the rotation values of the matrix are generated by taking the orientation of the z-axis into account and, finally, the resulting factor is scaled to normalize the magnitude value of gravity. Using the transformation matrix, it is possible to align the original reference system of the accelerometer to another coordinate system. The satisfactory results of this experiment show the need of implementing the here described method to enable the use of variable tilt measurements.