谐波驱动柔性臂系统耦合动力学建模及辨识

为研究谐波驱动的柔性臂系统耦合动力学建模问题,分别进行了谐波驱动模型的参数辨识和柔性机械臂振动特性的耦合动力学模型辨识。通过阶跃电流激励和低匀速转动实验辨识出了关节的库伦摩擦力,在伪随机二进制信号的激励下,辨识得到了包含驱动系统转动惯量和黏性摩擦因数的驱动传递函数模型,将其与实际结构系统比较验证了此模型的准确性。理论分析了振动耦合力矩和柔性臂应变输出电压之间的线性关系,辨识得到了从电机转动角位移到柔性臂应变电压输出之间的传递函数,其输出在时域和频域上都与实际系统比较吻合,说明了建立的传递函数模型对于实际系统的适用性。综合两个辨识得到传递函数模型,实现了对谐波驱动的柔性机械臂系统的耦合动力学建模。

Coupling Dynamic Modeling and Parameter Identification of a Flexible Manipulator System with Harmonic Drive

In order to study the coupling dynamic modeling method of a flexible manipulator system with harmonic drive, both the driven model parameters of the harmonic joint and the coupling vibration model of the flexible manipulator are identified. Coulomb friction of the joint is identified using step current excitation and uniform rotation experiments in a low speed. Then, the transfer function model of the harmonic joint is established and identified using a pseudo-random binary sequence excitation, and the moment of inertia and viscous friction coefficient of the harmonic joint are included in this model. Moreover, the predict outputs of the obtained model are in good agreement with the experimental results. The linear relationships between the strain output of the flexible manipulator and the coupling torque are presented from theoretical derivation. The transfer function model from the angular displacement of the servo motor to the strain output of the flexible manipulator are identified. Experimental results show these identified models match well with the proposed structure, both in the time and frequency domains. As a result, this coupling dynamic modeling method of the flexible manipulator system with harmonic drive is accomplished by integrating those two identification transfer function models.