非对称柔性支撑龙门双驱平台的解耦与同步控制

Decoupling and Synchronization Control of Asymmetric Flexure-Linked Dual-Drive Gantry Stage

针对采用非对称柔性支撑结构的龙门双驱运动平台,提出基于模型补偿扩张状态观测器的解耦与同步控制策略.考虑柔性支撑结构特点和负载加速度对龙门平动、转动模态的影响,采用拉格朗日方程建立了龙门动力学模型.依据该模型设计平动和转动控制回路并采用带有已知耦合项补偿的扩张状态观测器,估计并抑制由建模误差和未知耦合项等因素组成的总扰动.试验结果表明,该控制框架与解耦策略能有效解除双驱动轴间的动态耦合并抑制扰动,显著提升龙门试验台的动态响应和同步精度,且具有部署简单、所需测量模型参数少等优点.

A decoupling and synchronization control strategy based on a model-compensated extended state observer is proposed in control of a dual-drive gantry positioning stage with asymmetric flexure-linked structures.A gantry dynamic model considering the features of the flexure-linked structures and the impact of load acceleration is built using Lagrangian equations.Translational and rotational control loops are designed according to this model,while extended state observers with compensation of known coupling items in the model are deployed in each control loop to estimate and attenuate the total disturbances composed of unmodeled dynamics,unknown couplings,etc.The experimental results show that the proposed control strategy,which is simple to realize and requires few parameters to be measured,can effectively decouple the dynamics of dual axes and attenuates disturbances,greatly improving the dynamic response and synchronization accuracy of the gantry stage.