The Biaxial Wheel Test Rig

Operating load simulation tests are presently to the greatest extent the state of engineering for the development of new running gear components, because of their great strength of statement. These genuine operating load simulation tests on car wheels are only possible with relatively expensive test rigs.

Consequently a biaxial wheel test rig, based on an idea of the Fraunhofer Institut für Be-triebsfestigkeit (LBF), was developed at BMW and permits laboratory testing of a wheel under actual operating load conditions. With this test rig design, the lateral forces acting on the wheel without slip angle, are introduced positively by means of an inboard drum with lateral contact rings. A load-dependent camber setting is required with this design for the realization of friction coefficient values up to 1.0.

This paper describes the engineering design of the test rig and the required measures to realize optimal simulation quality.