Case: Road Load Tests

There are international procedures for determination of vehicle road load force. The road load is the amount of force needed to propel a vehicle forward at a constant speed. The ComTest solution employees coast down methods and applies to vehicles for on-road application.

The test track runs are recorded on a dry proving ground under reference conditions such as temperature, wind and atmospheric pressure. The driver must prior and after the test run enter information on the vehicle weight and weather conditions to the measurement system. Reading of weather conditions is automated and a wireless network is used.

The coasting vehicle on the test ground is affected by aerodynamic forces, tire rolling resistance and chassis drag.

The final result is a model of road load force as a function of speed during operation on a dry level road. The road load result is used to control chassis dynamometers at emission test beds for legislative certification tests of vehicles.