A free piston engine consists of one or more pistons which is/are displaced each in one cylinder through a combustion process followed by a motion which would return it back to its pre-combustion location. The free piston engine differs from conventional engines in several ways including the way this return occurs and the result of the power stroke (the motion associated with gas expansion after combustion). Firstly, the conventional engine uses a series of linkages to turn the linear motion of the piston into a rotational motion. The free piston engine is different because it uses the linear motion to produce a different type of energy which, in the case of this project, would be electrical current and fluid power. Historically, this type of engine has only been used for small commercial products, but with some modifications, it could be developed into an engine which could power vehicles and similar machines currently powered with traditional internal combustion engines. Because of its design, it can operate more efficiently which has become a major advantage in today's fuel economy minded society.