从时域和频域两方面研究了机载立体测绘相机三轴稳定平台中旋转行程较小的滚转轴伺服系统的辨识与设计问题。在时域方面提出了一种基于遗传算法的辨识方法, 讨论了遗传算法的原理与设计; 在频域方面提出了一种根据闭环频率特性测量数据求取系统开环频率特性的方法, 解决了滚转轴伺服系统由于旋转行程狭小而引起的开环频率特性难以直接测量的困难。根据辨识出的传递函数进行校正后, 控制系统满足设计要求。实验结果证明, 与传统方法相比, 本文使用的方法在测量条件较为苛刻, 行程范围较小, 噪声较大时, 辨识结果仍然可以较好地描述系统特性。校正后控制系统的闭环带宽可以达到121 rad/s, 稳定裕度为60°, 满足工程要求。

The identification and design of the roll axis servo system with a small journey range in an airborne three-axis gyro body-stabilized platform were discussed and researched by time domain and frequency domain methods. The identification method based on the genetic algorithm was presented by the time domain method and the genetic algorithm was also discussed.Moreover, the opened-loop frequency characteristics of the system were obtained according to the closed-loop frequency characteristic measuring data by the frequency domain method.These methods resolve the difficulty of roll axis servo systems with small journey range in directly measuring opened-loop frequency characteristics. On the basis of the transfer function identified, the control system corrected can meet expected indicators. Experimental results prove that the identification can nicely describe characteristics of the proposed system even in big noises, shorter journey ranges and poor measuring conditions. The closed-loop bandwidth of control system is 121 rad/s and the stability margin is 60° after correcting, which can meet the indicators of an engineer.