【作者】 胡生员；

【导师】 谭冠政；

【作者基本信息】 中南大学 ， 控制理论与控制工程， 2003， 硕士

【摘要】 智能机电人工腿主要由膝关节、执行机构、踝关节、脚以及智能控制器等组成，是一个复杂的非线性控制系统。它融合了智能控制理论、微电子技术、计算机控制技术、机械设计与制造、生物医学工程及康复医学工程等技术。它的关键部件是控制人工腿膝关节屈伸运动及小腿摆动的智能控制器，其常常采用模糊控制策略。智能人工腿的研制对于残疾人回归社会生活及改善生活质量具有决定作用，有着重大的社会意义。 本文对国内外人工腿研究工作的历史及现状作了综合分析，在此基础上指出现有人工腿控制器的问题，并提出了改进方案。在智能人工腿控制器的算法设计部分，首先介绍了遗传算法和模糊控制的基本内容，再由运行参数对模糊控制系统响应影响的分析，得出在系统运行过程中采用固定参数的模糊控制器不可能得到优异的动态及稳态性能，因此有必要根据系统的控制进程对控制器参数进行在线自动调整的结论。针对固定参数模糊控制器的上述缺陷，构造以系统动态误差为变量的运行参数自调整公式，提出了一种基于遗传算法优化的参数可在线自调整的模糊控制器的设计方法，计算机仿真结果表明这种模糊控制器比参数固定的模糊控制器在系统动态和稳态性能方面有较明显的改善。它具有很强的适用性，可被广泛运用于控制各种不同的对象。这对于智能人工腿模糊控制器的优化，实现实时、快速、精确的控制，最终提高人工腿的行走性能具有重要意义。 智能人工腿最大的特点是能跟随截肢者步行速度变化而变化，因此步速测量电路是智能人工腿中的一个重要组成部分。本文提出如下的步速测量方法：在预定的时间间隔内，连续采样速度测量值，并求取平均值，由平均值所对应的档位值作为人工腿控制器的给定值。在电路研制中首次采用先进微传感器——ENV-05F型角速度传感器，这种角速度传感器能瞬时捕捉大腿摆动的角速度；该传感器体积小，重量轻，响应快，非常适宜安装在人工腿内部。论文以该传感器为步速采样传感器，研制出基于AT89C51单片机的步速测量模块。实验表明，该模块电路能有效地感应健侧肢行走速度，满足实时测量的要求，并通过与人工腿控制器接口电路直接提供智能人工腿控制器的给定跟踪值。更多还原

【Abstract】 Intelligent electromechanical artificial leg is a complex nonlinear control system mainly comprising knee joint, actuator, ankle joint, foot as well as intelligent controller etc. This project integrates intelligent control theory, microelectronic technology, computer control technology, mechanical design and manufacture technology, biomedical engineering with rehabilitation medicine engineering etc. Its crucial part is intelligent controller, which controls bend and stretch of the knee joint of artificial leg as well as shank swing and often adopts fuzzy control strategy. The develop of intelligent artificial leg have significant social meaning and the role of decision for handicapped person’s returning society and improving the quality of life.This paper has synthesized and analysed the present situation and the history of research work of domestic and international artificial leg, and points out the problem of existing artificial leg controller on this foundation, and advances the improvement scheme. In the part of algorithm design of intelligent artificial leg controller, this paper has first introduced the basic content of genetic algorithm and fuzzy control. From the analyse of influence of operator parameters on the response of Fuzzy control system, it is educed that the excellent performance of dynamic and steady cannot be obtained when applying the fixed parameters Fuzzy controller. Then there is need that parameters should be online autoregulative according to the system control process. Aiming at the defect of the fixed parameters Fuzzy controller, This paper designs a formulae of self-tuning operational parameters and proposes a fuzzy controller whose operational parameters can automatically adjust according to the system’s current dynamic error based on genetic algorithms optimization. The result of computer simulation shows that it is more excellent than the fuzzy controller whose parameters are fixed in dynamic behavior and steady-state performances of system response. It has very strong applicability and can be utilized extensively in controlling various objects. It is very significant to enhance the performances of intelligent controller and realize real time, fast and accurate control so as to improve the walk performances of artificial leg.The excellent feature of intelligent artificial leg is that the speed of bend and stretch of its knee joint can change with the change of amputee’s walking speed, so the measurement module of walking speed is an important unit. This paper proposes a method of walking speed measure, which is sampling continuously the value of speedmeasurement and calculating the average in the time-interval intended. Then the rate corresponding to the average is used as the given value of controller. A new kind of advanced sensor, i.e.ENV-05F angular velocity sensor is adopted in the circuit for the first time. This kind of sensor can instantaneously catch the angular velocity of swing of thigh. This sensor is very suitable installed in the artificial leg due to its small volume, lightweight, responding quickly. Using this sensor as walking speed sampling sensor, this paper develops the measurement module of walking speed based on AT89C51 singlechip. Experimentation shows that this module circuit can effectively respond to the walking speed of healthy side leg and immediately offer intelligent controller given value through the interface circuit with controller of artificial leg.更多还原