6自由度平台的Washout滤波器设计及试验研究

Design and Test Research of Washout Filter for 6-DOF Platform

现代运动模拟器通常采用并联6自由度平台作为运动系统。由于平台的运动范围有限,就需要运用Washout滤波器,将实际运动转换成模拟器能够实现的信号。首先,设计经典Washout滤波器,对于高通加速度通道,平移和侧移方向都采用二阶高通滤波,升沉方向采用三阶高通滤波;倾斜协调通道纵向和侧向都选择二阶低通滤波器;高通角速度通道的3个方向都采用二阶高通滤波器。仿真证明Washout滤波算法能够提高模拟逼真度。然后,通过分析滤波器的自然响应频率和输出信号之间的关系,总结出Washout滤波器自然响应频率的选择原则。最后,在6自由度平台上针对所设计的滤波器进行试验。试验证明,所设计的Washout滤波器达到了预期的设计要求。

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.