An All Wheel Drive Spin-Torsional Dynamometer facility has been constructed at the Advanced Engineering Center of Ford Motor Company, adding unique capability for powertrain NVH testing.
This state-of-the-art facility is designed to concurrently deliver controlled rotational and torsional engine inputs to the drivetrain. While the facility supports the use of a live engine for input, it is also equipped with an engine simulator to allow detailed examination of the NVH characteristics of new powertrain configurations before prototype powerplants are available, without the need for a live engine. This will reduce development timing for new powertrains significantly.
The virtual engine consists of a driving dynamometer coupled with a high frequency servo-hydraulic torsional actuator. Four additional dynamometers are used to absorb load on the wheel hubs and a control system utilizes torque & speed feedback to produce repeatable experimental, analytical and hybrid vibration behavior in the sample. A wide range of NVH phenomena such as booming noise due to torque fluctuation, gear whine or rattle, low frequency vibration, and clunk can be simulated using torsional excitation. With this additional capability, Ford engineers will be able to develop and optimize NVH characteristics of powertrains, from the sub-system to component level and refine CAE models.
This paper describes the design, development, and implementation of the system. It includes key specifications, functional capabilities, and examples of testing methods.