并联机构动力学建模及伺服系统参数辨识

研究一种三自由度并联机构动力学建模及伺服系统参数辨识方法．首先导出了外移动副驱动，含平行四边形支链结构的位置、速度及加速度逆解模型，并利用虚功原理建立其刚体动力学逆解模型．在此基础上，提出了辨识该并联机构伺服系统参数的一种方法．该方法采用变频三角波输入，克服了伪随机二位式序列信号幅值变化大、易造成对伺服电机冲击和引起其速度环开环等问题，且通过附加惯性负载，可将包括伺服系统转动惯量在内的所有参数辨识出来，为系统动态性能在全工作空间内取优奠定了基础．

Dynamic Modeling of Parallel Manipulator and Parameter Identification of Its Servo System

Aimed at a parallel manipulator with three degrees of freedom translation, a method on dynamic modeling of parallel manipulator and parameter identification of its servo system is presented.First, the reverse solution models of position, velocity and acceleration of parallel manipulator including the parallelogram strut structure are deduced.Then its dynamic model of rigid body is set up by using the virtual work principle.Based on the above model,the triangle shape input with variable frequency is adopted to overcome the disadvantage of pseudo-random number sequence in parameter identification process,i.e.making the change of vibration amplitude of motor big,easy to impact motor and result in its velocity loop open and so on.Moreover,the rotary inertia can also be identified by the additive mass, and the above outcome will lay a solid foundation for the best performance of the system in the whole workspace.