Optical Flow and Inertial Navigation System Fusion in UAV Navigation

In recent years navigation on the basis of computation of the camera path and the distance to obstacles with the aid of field of image motion velocities (i.e. optical flow, OF) became highly demanded particularly in the area of relatively small and even micro unmanned aerial vehicles (UAV). Video sequences captured by onboard camera gives the possibility of the OF calculation with the aid of relatively simple algorithms like Lucas-Kanade. The complete OF is the linear function of linear and angular velocities of the UAV which provides an additional means for the navigation parameters estimation. Such UAV navigation approach presumes that on-board camera gives the video sequence of the underlying surface images providing the information about the UAV evolutions. Navigation parameters are extracted on the basis of exact OF formulas which gives the observation process description for estimation based on Kalman filtering. One can expect the high accuracy of the estimated parameters (linear and angular velocities) because their number is substantially less than the number of measurements (practically the number of the camera pixels).