The purpose of this thesis was to investigate different methods do measure velocity of pistons in pneumatic cylinders at Bosch Rexroth Teknik AB. Through information of velocity the adjustment of a cylinders damping can be done easier.A future transducer will be used by salesmen, service personnel and customers. This requires a sensor that is easy to apply and use. It is also desirable that the sensor is cheap. A number of possible methods to measure velocity have been presented.