The aim of the thesis is to study and evaluate the usage of Shape Memory Alloys (SMA) as actuators for end-effect in robots. SMA are a type of smart materials which have the ability to recover their shape when temperature is increased, even under high applied loads. This fact makes them very useful in a wide range of applications in the mechanics and robotics, civil and biomedical fields. The thesis is organized in two main steps: 1) Literature analysis and understanding of SMA theoretical behaviour 2) Characterization of SMA coiled springs which can be used in robot end-effect