A torsional vibration measurement system

At the development stage of automobile construction, many power-train configurations may be considered. Due to complicated coupling mechanisms, the natural frequencies of the combined system are difficult to predict. It is therefore necessary to run tests on automotive subsystems under realistic operating conditions. To fully understand the dynamic behavior, a study of both torsional and translational motions along the driveshaft is necessary. The computerised torsional measurement system described has been designed to measure translational and torsional motion simultaneously at points along a rotating shaft. It overcomes the drawbacks of existing systems that measure torsional vibrations, which are either expensive, require shaft modifications, or do not account for the coupling between torsional and translational motions