Nitinol is a SHAPE MEMORY ALLOY made of nickel and titanium that SHORTENS  in length when current flows through it. Nitinol changes shape when heated but returns to its original shape when cooled. Nitinol requires a "retuning force" to return it to its original length after current has been turned off. It does not return to its original length by itself.

In this article we build a speech recognition project. The two articles to follow will be speech recognition interfaces. The first interface will connect to a robotic arm (OWI's 007 Robotic Arm Trainer) to create a speech controlled robotic arm. The second interface will be a general purpose PC board that will be easily interfaced to your own projects.