A state estimation-based model predictive control strategy is proposed to deal with the constraints and the poor robustness problems existing in the system of servo motor driven pumpcontrolled asymmetric cylinders.A state-space model with input and output constraints is developed according to the principle of pump-controlled cylinder system and the practical requirements.The model predictive control is introduced to avoid the nonlinearity of valve switching and to improve the performance of constrained optimal control.The Kalman filter is combined to compensate the impacts of disturbance and modelling errors and to improve the robustness of the system.Simulation results of the strategy show that offset-free reference tracking is achieved,no over-limit of the input and no overshoot of the output are guaranteed,and model mismatch and disturbance are handled satisfactorily.Experimental results with the strategy show that the position has no overshoot with a relative tracking error of about 0.5 ％ and the effects of disturbance and modelling error are small.Hence,the proposed method is applicable to the real pump-controlled systems,improves the control performance under input and output constraints,and allows for certain disturbance and modelling error.%针对伺服电机驱动泵控非对称液压缸系统存在约束和鲁棒性差等问题,提出了采用状态估计的模型预测控制策略.根据泵控液压缸系统的原理和实际要求,建立了含输入和输出约束的状态空间模型;引入模型预测控制,避免了阀切换带来的非线性,提高了约束优化控制性能;结合卡尔曼滤波器,补偿了干扰和模型误差的影响,提高了系统的鲁棒性.仿真结果表明,所设计的控制策略能够实现无偏移跟踪,保证输入不超限、输出无超调,且具有很好的处理干扰和模型失配的能力.实验结果中,液压缸位置无超调,相对位置跟踪误差约为0.5％,干扰和模型误差对控制性能的影响很小.可见,所提方法能应用于实际泵控系统,提高输入、输出约束下的控制性能,容许一定的干扰和建模误差.
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