Search Results

The design and validation process of a new car requires detailed knowledge of the interaction of dynamic forces and moments introduced into the rotating wheel. These forces are measured under operating conditions with appropriate sensors and transducers. Due to the effects of the dynamic masses, the loads should be sensed as close to the tire/road interface as possible using a wheel load transducer. Currently, existing transducers are quite heavy, not very accurate and elaborate calibrations and computations have to be performed. With the newly developed VEhicle LOad Sensor (VELOS), these deficiencies are overcome. Examples of dynamic force and moment calibrations with the original tire are presented, as well as road load data acquisitions comparing results from the VELOS with those of the axle transducers on a passenger car under different driving maneuvers.

To advance the present state-of-the-art of testing oil lubricated truck wheel hub seals (hereafter referred to as oil bath seals) from fairly simple tests which allow static offset in the radial direction towards real-time road simulation, an investigative test development project was initiated. Combining the know-how and resources of manufacturers of oil bath seals and servohydraulic test equipment, a more realistic approach to seal testing was to be developed. Of importance to the project was the successful development of a five degree of freedom motion transducer used to measure the relative motion of the hub vs. the spindle in the seal location. Conducting extensive proving ground measurements and analyzing the data allowed the generation of a test sequence typical for the seal application. A special computer controlled servohydraulic test machine was designed and built which is capable of real-time simulation of the five degrees of motion acquired on the road.