Optimal Attitude Sensor Placement and Modal Frequency Identification of Large Space Structure

With the flexible vibration influence to attitude signals in large space structure, the issues of modal parameter identification and optimal attitude sensor placement are investigated in this paper. By constructing corresponding Hankel matrix using on-orbit input and output signals, the modal parameter identification of large space structure is implemented based on the observer/Kalman filter identification (OKID) method. In addition, optimal attitude sensor placement of the large flexible structure by using genetic algorithm is also studied. In numerical simulations, the distributed placement of the attitude angle and angular velocity are discussed by establishing a large plate structure model, and the modal frequencies of the model are identified by the OKID algorithm. The simulation results illustrate that the flexible vibration will obviously affect the attitude angular velocity signals and the OKID algorithm can effectively identify most of frequency parameters.