Department of Biomechanics, School of Life Science and BioEngineering, Beijing University of Technology, Beijing, People's Republic of China.
ASAIO J. 2010 Nov-Dec;56(6):510-6. doi: 10.1097/MAT.0b013e3181ede369.
Both the intra-aorta pump system and the circulation system are nonlinear systems with external perturbation and internal uncertainty. Classical control methods are suggested for linear systems. Therefore, a global sliding mode controller (GSMC) is reported in this article. A dynamic disturbance compensator was used to estimate the uncertainty of the controlled intra-aorta pump system for eliminating chattering effect. Simulations were performed to verify the robustness and dynamic characters of the controller. Simulation results demonstrate that the chattering effect of the controller output is eliminated. The settling time of step response of flow rate (5 L/min) is 0.08 seconds without overshot or steady-state error. When the load torque step disturbance increases to 0.4 Nm, the settling time of the controlled system is 0.025 seconds. When the desired flow rate is pulsatile flow, the dynamic response time is 0.08 seconds, and the maximum flow rate error is 0.03 L/min. To verify the dynamic character of the GSMC, an experiment was conducted. Because the feedback frequencies of rotational speed and flow rate in the experiment were slower than the ones in the simulation, the performance of the controller deteriorates. The experiment results illustrate that the settling time of step response of flow rate (5 L/min) is 0.26 seconds, and the flow rate error is 0.1 L/min.
主动脉内泵系统和循环系统都是具有外部扰动和内部不确定性的非线性系统。经典控制方法适用于线性系统。因此，本文提出了一种全局滑模控制器（GSMC）。采用动态干扰补偿器来估计受控主动脉内泵系统的不确定性，以消除抖动效应。进行了仿真以验证控制器的鲁棒性和动态特性。仿真结果表明，控制器输出的抖动效应被消除。流量阶跃响应（5 L/min）的稳定时间为 0.08 秒，没有过冲或稳态误差。当负载转矩阶跃干扰增加到 0.4 Nm 时，控制系统的稳定时间为 0.025 秒。当期望流量为脉动流量时，动态响应时间为 0.08 秒，最大流量误差为 0.03 L/min。为了验证 GSMC 的动态特性，进行了实验。由于实验中转速和流量的反馈频率比仿真中的慢，因此控制器的性能会下降。实验结果表明，流量阶跃响应（5 L/min）的稳定时间为 0.26 秒，流量误差为 0.1 L/min。
