One of the most challenging fields of engineering is system control, which was established with the aim of automating complex systems without human interaction. Thus, by means of the feedback theory, it is intended to modify the most critical system variables to obtain the desired behavior. Event most of the applications are linear control-based, there exist some occasions where it becomes necessary to apply other approaches for obtaining reasonable results. During the last years, a new type of elements named intelligent materials have been discovered and developed. They yield very interesting properties although they are extremely difficult to control with classical techniques. Even they have a limited number of applications due to their complexity, the actual increase in computer power make them attractive. In such a way, the continuous improvement of their size and performance have converted these intelligent materials into a future reference. The aim of this dissertation is to suggest solutions to several problems controlling SMA actuators. Due to their high hysteresis, a novel methodology for their identification, adjustment and implementation in the control loop is presented improving the conventional linear methods. Thus, several experimental results and comparisons among several control methods are presented. Furthermore, the initial state search problem in the SMA actuator has been solved. The presented contributions of this thesis have been tested and fully optimized in order to be installed in a real time actuation platform. In such a way, a new field of applications and future works is established suggesting a wide range of new possibilities.
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