Compensating magnetic disturbances on MARG units by means of a low complexity data fusion algorithm

The paper proposes a new algorithm for the estimation of orientation of MARG (Magnetic, Angular Rate and Gravity) units, capable of compensating the influence of short-duration magnetic disturbances on the magnetometer, with application in motion tracking for rehabilitation. The proposed algorithm has been designed starting from a widely used low-complexity orientation estimation algorithm, based on the gradient descent minimization. The proposed algorithm has been validated by means of laboratory experiments, aimed at verifying its capability of correctly estimating orientation, by compensating the magnetic disturbances both in static and in dynamic conditions. The results of such experimental phase are presented and discussed in the paper.