The working group impact dynamics carries out research and development in two main fields:
Calibration of force transducers by means of impulse forces
Für die Kalibrierung von Kraftaufnehmern mit stoßförmigen Kräften werden speziell entwickelte Messeinrichtungen eingesetzt. Zwei Massekörper werden zur Kollision gebracht, an einem ist dabei der zu untersuchende Kraftaufnehmer angebracht.
Die bei der Kollision entstehenden Beschleunigungsverläufe werden zusammen mit dem Ausgangssisgnal des Kraftaufnehmers aufgezeichnet. Aus der Beschleunigung kann mit Hilfe der Masse der beiden Massekörper die einwirkende Kraft ermittelt werden. Diese wird als Referenzkraft für die Kalibrierung herangezogen.
Dynamic torque calibration with sinusoidal excitation
The calibration of torque transducers using dynamic excitations is carried out with a dedicated measuring device consisting of a vertical shaft assembly. A rotational exciter generates sinusoidal oscillations. These oscillations induce a dynamic toque to the transducer due to the coupled components arranged in the shaft assembly. The analysis of the dynamic behaviour of the shaft assembly is carried out based on angular acceleration measurements at different positions of the shaft and on the output voltage of the transducer under test.
The dynamic behaviour of torque and force transducers is described by means of a mechanical model.
Based on the measurement data, the properties of the transducer are described by the model parameters.
The working group transfers knowlegde and experience from its field of work:
- Co-operation within the framework of the Deutscher Kalibrierdienst DKD.
- Consulting support for society and industries concerning questions of dynamic force and torque applications.
- 2 shock force calibration devices (for up to 20 kN and up to 250 kN)
- research for the calibration of impact hammers
- model-based description of force transducers
- finite element modelliing for the validation of measurement results
- measuring device for the generation dynamic torque in a frequency range of 10 Hz up to 1 kHz
- ausxiliary measuring devices for an independent determination of torsional stiffness, mass moment of inertia and rotational damping
- model-based description of torque transducers
Measurement amplifier calibration
Research for the traceable dynamic calibration of bridge amplifiers and conditioning electronics of strange gauge based transducers is carried out in collaboration with working group 2.12 Ratio and Sampling Techniques of PTB.
Publications of working group 1.73 Impact Dynamics can be found here.
European Metrology Research Programme (EMRP)
Research and development in the field of impact force calibration and in the field of dynamic torque calibration has been carried out in the context of the European Metrology Research Programme in the research project Dynamic Measurement of Mechanical Quantities jointly with eight other European metrology institutes. The results of the research project have been presented in issue 02/2015 of the PTB-Mitteilungen, which is available online at the website of PTB .
Collaboration with other national metrology institutes
I addition to the engagement in the context of the EMRP, the working group collaborates with partners from national metrology institutes all over the world.