Dynamic force calibration using impact hammer

Many measurements are dynamic. This applies not least in the area of force. One example is vehicle collision testing, where the forces that affect the test dummies rapidly change during the crash. Today, the force transducers used during these tests are calibrated quasi-statically. This means that one cannot be sure exactly how the sensor behaves throughout the crash or how it reacts to various dynamic events.

Great demand

RISE has been working for a long time to develop traceable dynamic measurements. Previous projects have primarily focused on pressure, but the goal has always been to expand competence and ability in related areas such as force and torque. There is a great demand for accurate and reliable measurements of dynamic force, as the work within the RISE knowledge platform for dynamic measurements has also shown.

Impact hammer as reference

Previous European projects have explored methods for dynamic force measurements. One method involves using an impact hammer with a known load pulse as a reference. Impact hammers are commonly used both in industry and research and have the advantage that the measurement can be carried out on an existing installation. Doing so considers the dynamic behaviour of both the force sensor and the mechanical structure in which the sensor is mounted. The calibration can also be performed at a frequency and force close to that which the instrument is typically operated, reducing the need for complex modelling or compensation techniques.

Strengthens Swedish competitiveness

The project will develop competence and ability in dynamic characterization of force transducers by researching, analysing and developing an impulse hammer as a reference standard, developing measurement methods and investigating sources of measurement uncertainty.

The project makes it possible in the future to offer Swedish industry and business new calibration services that better reflect real areas of use and conditions. The project will improve the reliability of dynamic force measurements and thus strengthen Swedish competitiveness.