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Sensitivity table method (STM), which is a most widely used computer-aided alignment technology in optical system alignment, faces a problem that is how to determine the correctness of the applied object and established sensitivity table. In order to solve the problem, two criteria for applying STM correctly are concluded, one is determining the linearity relation between misalignments and wavefront aberration, the other one is establishing the effective sensitivity table by monitoring its condition number. Two optical systems are tested in this paper, and experimental results show the correctness of the proposed method.

In order to solve the problem of insufficient accuracy and reliability of ship position display in AIS(Automatic Identification System) system, a federated Kalman filter is designed, an open algorithm architecture is built, AIS and BDS positioning information sources are selected for fusion, and the information fusion part of the federated Kalman filter framework is improved by IMMF algorithm and covariance crossover algorithm to obtain more accurate and reliable target position information and ship motion state. Simulation experiments are carried out, and the experimental results show that, compared with GPS positioning or BDS(Bei Dou Navigation Satellite) positioning in AIS alone, AIS/BDS combined positioning based on federated Kalman filter structure has higher system fault tolerance, positioning accuracy and stability, and improves the safety of ship navigation.