Hariri Ali, Wang Le Yi
DTE Energy, One Energy Plaza, Detroit, Michigan, 48226.
Open Biomed Eng J. 2011;5:98-109. doi: 10.2174/1874120701105010098. Epub 2011 Dec 30.
During the past few decades, biomedical modeling techniques have been applied to improve performance of a wide variety of medical systems that require monitoring and control. Diabetes is one of the most important medical problems. This paper focuses on designing a state feedback controller with observer to improve the performance of the insulin control for type 'I' diabetic patients. The dynamic model of glucose levels in diabetic patients is a nonlinear model. The system is a typical fourth-order single-input-single-output state space model. Using a linear time invariant controller based on an operating condition is a common method to simplify control design. On the other hand, adaptive control can potentially improve system performance. But it increases control complexity and may create further stability issues. This paper investigates patient models and presents a simplified control scheme using observer-based feedback controllers. By comparing different control schemes, it shows that a properly designed state feedback controller with observer can eliminate the adaptation strategy that the Proportional-Integral-Derivative (PID) controllers need to improve the control performance. Control strategies are simulated and their performance is evaluated in MATLAB and Simulink.
在过去几十年中，生物医学建模技术已被应用于提升各类需要监测与控制的医疗系统的性能。糖尿病是最为重要的医学问题之一。本文着重于设计一种带观测器的状态反馈控制器，以改善“I”型糖尿病患者的胰岛素控制性能。糖尿病患者体内血糖水平的动态模型是一个非线性模型。该系统是典型的四阶单输入单输出状态空间模型。基于运行条件使用线性时不变控制器是简化控制设计的常用方法。另一方面，自适应控制有可能提升系统性能。但这会增加控制复杂度，并可能引发更多稳定性问题。本文研究患者模型，并提出一种使用基于观测器的反馈控制器的简化控制方案。通过比较不同的控制方案，结果表明，精心设计的带观测器的状态反馈控制器能够摒弃比例积分微分（PID）控制器为提高控制性能所需的自适应策略。在MATLAB和Simulink中对控制策略进行了仿真，并评估了它们的性能。
