Shape Memory Alloys are extensive applied in Medical Robotics nowadays as active ele-ments. They could be used as actuators, which are abie to perform accurate movements in minimal invasive surgery (MIS). In MIS the precision of the incisions has to be guar-anteed. The need of precision leads to try to find a reliable approach that describes the behav-ior of SMA. Departing from the knowledge of the characteristics of SMA, a survey of Models available is performed. This models describe the response of the SX/IA under different conditions. Finally the goal is to determine the most important features in the model and compar