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State Estimation for the Unknown Motion Model with Bearing-only Measurement

This paper presents the problem of state estimation for moving objects with bearing-only measurements in the case that the a priori motion model is unknown, i.e., its acceleration is absolutely unknown, which can not be dealt with by the mainstream Kalman-like schemes based on the known motion model. First, the essential reason disadvantage of the bearing-only measurement in the states estimation is described, and hence an alternative measurement is proposed. Then, an unknown input observer is proposed to estimate the position and velocity of the object. Finally, the numeric simulation demonstrates the effectiveness in terms of estimation accuracy and terminative time.