Estimation of magnetic declination angle using reduced QUEST for an unmanned aerial vehicle

Measurement of the heading angle which is free from magnetic declination using several GPS antennas is widely applied, but it is not suitable for small unmanned aerial vehicles because of their limit of the payload and body length. In this paper, we propose a method to estimate the magnetic declination angle using an inertial measurement unit(IMU) and only one GPS antenna. The method consists of 1) estimation of the acceleration of the motion from GPS measurements and 2) estimation of the magnetic declination angle using the estimated accelerations and IMU measurements. We show that the estimation of the magneticdeclination angle results in reduced QUESTflO], that is an eigenvalue problem of 2 × 2 real matrix. Flight experimental results using an unmanned helicopter demonstrate the effectiveness of the proposed methods.