Portable absolute orientation estimation device with wireless network under accelerated situation

In this paper, we develop an absolute orientation estimation device equipped with a wireless network. Accelerometers and magnetometers are used to measure the gravity and the geomagnetic field respectively. Gyroscope sensors are used to measure the local angular velocity. The geomagnetic field varies according to the environment. Therefore the device can obtain the information about the magnetic field through the wireless network. The orientation estimation task can be also requested to the other computers with the wireless network. By integrating the measured gravity and geomagnetic field with the local angular velocity using Sigma-Points Kalman Filters (SPKFs), the stability and the robustness of estimating the absolute orientation are improved over either sensor alone. We also propose an estimation method which excludes the effect of motion and magnetic disturbances for the accurate estimation.