Publication
An in-field magnetometer calibration method for IMUs
Sarvenaz Salehi Mourkani; Navid Mostofi; Gabriele Bleser-Taetz
In: Proceedings of IROS Workshop on Cognitive Assistive Systems: Closing the Action-Perception Loop. IROS Workshop on Cognitive Assistive Systems: Closing the Action-Perception Loop (CAS-12), October 7, Vila Moura, Portugal, Keine Angabe, 2012.
Abstract
Magnetometers are one of the most common
aiding sensors used in Inertial Measurement Units (IMU) to
provide motion tracking, the latter being an important task in
Cognitive Assistive (CA) systems. The basis for accurate motion
tracking is a well calibrated sensor. Therefore, this paper
presents an easy-to-use method for in-field magnetometer
calibration and alignment with inertial sensors in an IMU. In
the first step of the calibration procedure bias, scale factors and
non-orthogonality parameters are estimated based on
magnitude information and data collected under motion. In the
second step misalignment parameters are obtained from
inclination using gravity measured by accelerometers under
static conditions. In each step the initial estimation of
parameters based on linear least squares followed by a
nonlinear optimization leads to reliable results for all the
calibration parameters. Different performance aspects of the
method are evaluated in several tests using real data.