Improving robustness of the MAV yaw angle estimation for low‐cost INS/GPS integration aided with tri‐axial magnetometer calibrated by rotating the ellipsoid model

This study designs a method to improve the robustness of the micro air vehicle (MAV) yaw angle estimation for low‐cost inertial navigation system/global positioning system (INS/GPS) integration by using a tri‐axial magnetometer. Observability properties of the integration navigation system are first analysed, indicating that all attitude angles have great observability with the aid of the heading measurement by a magnetometer, while the observability of yaw angle is low in traditional INS/GPS. To improve the robustness of yaw angle estimation, the authors calibrate the tri‐axial magnetometer according to the rotating ellipsoid model and establish a fault detection and isolation mechanism to adjust the weight of magnetic‐measurement adaptively and dynamically in integration navigation. The simulation and experiment results show that the proposed method can calibrate the tri‐axial magnetometer properly and screen out the abnormal magnetic measurement for the robustness of yaw angle estimation, suggesting that this technique is a viable candidate for MAV navigation and control applications in complex magnetic fields.