Design of an Optical Servosystem using a Simultaneous Optimization of Structure and Control System

本研究提出一种新的设计理念，考虑构造由结构系统和控制系统组成的机构。首先，提出了一种基于共振频率和反共振频率敏感性分析的结构动力优化方法。重新定义了抗谐振频率的灵敏度。提出了一种利用该灵敏度从频响函数（FRF）中消除共振峰的方法，将该共振的频率和相邻的反共振底部的频率修改为相同的值。通过消除影响激光唱机伺服控制功能的共振峰，对激光唱机光学驱动器进行了优化设计。该播放器，与这个优化的驱动器，显示了一个优秀的声音播放性能。其次，提出了一种结构与控制系统同时优化设计的方法。在系统对高阶自然模态稳定的约束条件下，通过灵敏度分析同时优化结构和控制参数的设计变量，使系统对白噪声和色噪声干扰的响应最小。该方法采用三种模型，即有限元法的原始空间模型、设计控制系统的简化模态模型和保证系统稳定性的原始模态模型。通过对某钢板的振动控制实验，验证了该方法的有效性和实用性。

This study proposes a new design concept that takes into consideration the construction of a mechanism that consists of a structural system and a control system. Firstly, a method for structural dynamic optimization is proposed using sensitivity analysis of resonance and anti-resonance frequencies. The sensitivity of the anti-resonance frequency is newly defined. An approach for eliminating the resonance peak from the frequency response function (FRF) is proposed using this sensitivity, modifying both the frequencies of this resonance and the neighboring anti-resonance bottom to the same value. Optimum design of an optical actuator for a compact disk player is performed practically by eliminating resonance peaks which deteriorates its servo control function. The player, with this optimized actuator, shows an excellent performance of sound playback. Next, an approach is presented for simultaneous optimum design of structure and control system. The design variables of both structure and control parameters are optimized simultaneously by the sensitivity analysis in order to minimize the response dur to disturbances of both white noise and colored noise under the constraining condition that the system is stable against high order natural modes. Three kinds of model are adopted in this approach, namely the original spatial model by FEM, the reduced modal model for designing control system and the original modal model for assuring stability of the system. Validity and usefulness of the presented approach are verified by an experiment of vibration control with a steel plate.