A group of German engineers has created a new system that virtual connects two spatially-separated test benches and simulates a mechanical shaft.
The new setup is the result of a partnership between Aachen-based FEV and the Institute for Combustion Engines (VKA) at RWTH Aachen University. The group says that the linked benches save time and help prevent damage, and are able to test hybrid powertrains that are not yet mechanically compatible.
“The dynamometers in both test benches are controlled in a way that achieves the equivalent system behavior of a real mechanical shaft,” explains Professor Stefan Pischinger, president and CEO of FEV Group and director of the VKA.
“With this, an interaction – for example, between engine and transmission – is achieved during the prototype phase before both components are able to be adapted, thus saving important development time.”
The test environment consists of test benches that are linked by a real-time deterministic EtherCAT connection, and programmes can be run on the system as if the components were physically linked. Its creators say that it will change the development process by introducing elements into testing programmes that could only have been done previously on a vehicle or complete powertrain.
Dr Albert Haas, group vice president, test systems at FEV, explains how the new system speeds up testing: “In conventional development processes complexity increases step-wise as we move from a single component up to system testing in the vehicle. First the e-motor, the engine and the transmission are tested separately in single test cells. The real interactions between the different components, though, cannot be evaluated until composite system testing can be accomplished on a full powertrain test bench. The virtual shaft makes a valuable contribution to handling the increasing complexity of modern hybrid drives, and provides the opportunity to make the development process more efficient.”
August 3, 2015