利用形狀記憶合金(SMA)的結構位置模糊控制研究.pdf

1、沈陽建筑大學碩士學位論文利用形狀記憶合金（SMA）的結構位置模糊控制研究姓名：劉暢申請學位級別：碩士專業(yè)：結構工程指導教師：閻石2009-02碩士研究生學位論文 ABSTRACT III Abstract In recent years, smart materials in civil engineering have been rapidly developed, in which shape memor

2、y alloy (SMA) has been extensively researched. SMA has many unique mechanical and physical properties, which common metals don’ t have. Such as the shape memory effect (Shape Memory Effect, ref

3、erred to as SME), superelasticity (pseudoelasticity, referred to as PE), high damping characteristics, resistance characteristics (Electrical Resistance property, referred to as ER ) and so on, th

4、ese characteristics can be widely used in engineering. The use of SME of SMA, can achieve the position control for the structures. As a result of the unique physical and mechanical properties

5、 of SMA, its application on actuating characteristics has good prospects. However, there was lack of reports on the development of the SMA actuation property and rare investigation on the position cont

6、rol of an object using SMAs. Due to the physical characteristics of SMA with non- linear, temperature delay and time- varying characteristics, its mathematical model is difficult to be established

7、. Therefore, it has a great challenge to establish a precise mathematical model . How to use an advanced control algorithm combined with the actuation property of the SMAs becomes a key problem

8、 to be solved in the future. The deformation of SMA materials can be achieved by the method of changing the temperature by electrically heating. Because there is a nonlinear relationship betwe

9、en the heating current and SMA displacement, a fuzzy control model which is suitable for the position control is established in the paper based on the existed models, and the position control

10、 is numerically and experimentally applied. On the basis of the investigation, a new mechanical model for the position control of a structure is also established. This paper has introduced the r

11、esearch background, purpose and significance of the research, and elaborated its current status at home and abroad. At the same time, it has presented the SMA actuation model s, and the main

12、parameters, And then a mechanical mocel for the entire location control system is deduced, and the nonlinear relationship between the SMA input current signal and the output displacement signali

13、s obviously shown in the results of the investicgation. In addition, through the experiment of temperature- induced martensitic transformation of SMA shape memory effect, the actuation characteristics

14、in the shape memory effect stage of the SMA have been further studied, and the relationship of temperature and output displacement is also discussed. In the last part, a fuzzy controller has

15、 been designed and the position control of the structure is experimentally realized. The efficiency of the fuzzy control using the SMAs is validated in the paper and the future research direct