基于自适应算法的Stewart平台微振动低频激励控制研究

针对空间微振动环境模拟的需求,以Stewart平台为对象,研究低频微振动激励控制.传统定增益控制器需要反复调节参数来获取满意的系统输出,同时由于摩擦等因素引起的非线性现象,导致难以在低频段建立精确的系统模型,以上问题均给控制器的设计带来困难.为此,设计一种自适应控制器加传统PID控制器的控制方案,并针对自适应控制器对于非参数不确定性等因素敏感的问题,采用dead-zone技术对自适应律进行修正,以提高控制器的鲁棒性.将此算法应用于Stewart微激励控制系统中,实验结果表明系统平台可以很好的输出单自由度与多自由度低频正弦激励,验证控制器在实际工程中的有效性.

Low Frequency Control of Micro Vibration Generation Using Stewart Platform Based on Adaptive Algorithm

The Stewart platform is used to simulate the micro vibration environment in space. The low frequency control of micro vibration generation is conducted based on the platform. The parameters are tuned repeatedly to get a satisfied performance of the system in the traditional fixed gain controllers. Meanwhile, the nonlinear phenomenon caused by the friction makes it difficult to build an accurate system model. With the problems described above, it is difficult to design the controller for the system. To solve the problems, an adaptive controller is presented. Due to the sensitivity of non parameter uncertainties, the dead zone technique is used to modify the adaptive laws to improve the robustness. The algorithm is applied to the multi degree micro vibration excitation control system. The experimental results show that the platform can generate low frequency sinusoidal signal excitations in both one degree and multi degree direction. The experimental results verify that the method is applicable for practical engineering problems.