Well covered... Webasto is using HBM’s catman®AP for testing retractable hardtops
Volvo C70 convertible drivers enjoy this feeling: At the push of a button the top is retracted – and off you go.
To make sure that nothing goes wrong when retracting and deploying the technically demanding hardtop system, extensive tests were made already during its development. Webasto AG, sited in Stockdorf, Germany, an international automotive supplier and developer of the retractable hardtop for the Volvo C70 convertible, relies on test and measurement equipment from HBM for this purpose. They use HBM transducers, the MGCplus amplifier system, and innovative and easy-to-use catman®AP software for recording and processing measured values.
Typical measurement tasks were:
- Stiffness measurements (complete hardtop system and components)
- Natural frequency measurements and recording of road profiles (complete hardtop system and vehicle)
- Closing speeds
- Functional tests on hardtop system and components (voltages, currents, forces, pressures, torques, angles, displacements, etc.)
…and measurement of blocking forces. Blocking forces are measured to make sure that the components of the hardtop system tolerate blocking in any intermediate position without suffering damage or subsequent impairment of functionality. Furthermore, these tests provided a basis for comparison to the FEM calculations.To enable blocking forces to be measured as conveniently as possible, Webasto tested the C-segment drive in a component test stand the following transducers were used:
- Cylinder force: U3 HBM force transducer, 10kN
- Cylinder displacement
- Cylinder pressures on piston and rod side: P8AP HBM pressure transducer, 500bar
- Blocking force at the driven rod: U3 HBM force transducer, 2kN
The diagram shows an example of the measurement quantities of pressure and force, evaluated and visualized using catman®AP.
catman®AP software is easy to use and thus facilitates Webasto’s daily work. catman®AP’s sensor database, in particular, saves time and significantly reduces error rates when setting up the amplifier. The software’s flexibility also enables Webasto to quickly respond to new measurement tasks. The second field of applications in which Webasto uses catman®AP is analysis and documentation, where the filter and frequency analysis functions provided are especially useful.
