Improved UFIR Filter for Fusing Recent INS-assisted Visual Measurement under Colored Measurement Noise in UAV Landing

In this paper, we discuss the landing process of unmanned aerial vehicles (UAVs) employing inertial navigation system (INS) and visual measurement. Employing the integrated scheme, an improved unbiased finite impulse response (UFIR) filter is developed for fusing recent INS-assisted visual measurement under colored measurement noise (CMN). The UFIR filter developed for CMN and called cFIR filter is proposed, and then the hybrid UFIR/cFIR filter is developed to work in parallel. The Mahalanobis distance is used to select better results as the final result of the filter. It is shown experimentally that the proposed method enhances the accuracy and reliability of data fusion, thereby improving the overall performance of UAV autonomous landing systems.