Abstract: A large number of modern motion simulators employ 6-DOF platform as motion system. A Washout filter is critical to convert real movement to signals that simulator can simulate since the scope of a simulator is limited. Firstly, a classical Washout filter is designed and the basic form of the filter is confirmed. Two second-order high-pass filters are utilized in the channels of surge and sway. A third-order high-pass filter is used in the heavy direction. Two second-order filters are adopted in surge-tilt coordinate and sway-tilt coordinate channels. Three second-order high-pass filters are applied in the rotary channels. The designed Washout filter is proved to be capable of improving fidelity by simulation. Secondly, a principle of choosing the Washout filter’s natural frequency is concluded by analyzing the correlation between natural frequency and output signal. Finally, the Washout filter is tested on a 6-DOF platform. The experiments demonstrate that the Washout filter reaches the goals of design.

Key words: 6-DOF platform, Motion simulation, Washout filter