Representative Road Selection and Route Planning for Commercial Vehicle Development

Measuring loads for durability as well as emission and consumption for drivetrain assessment on public roads are indispensable parts of the commercial on-road vehicle development. Often, manufacturers have been using certain reference routes over many years and gained much experience in the relation of the results to the real world performance of their vehicles. However, known shortcomings of existing routes, novel vehicle concepts or markets make the definition of new routes an important task for the corresponding development departments. To be able to correlate the results collected on a route to different types of vehicles for different markets with a high usage variability, two requirements need to be fulfilled. First, it is mandatory to cover all important road conditions on that route (different types of roads, e.g. highways, major or minor, country and city roads, smooth and rough, flat and steep roads, high and low traffic density etc.). Second, it is important to know the distribution of these road conditions in the market of interest. Thus, we describe two aspects of that process, namely how to find a set of possibly unconnected roads representing all relevant road conditions in a region and how to find a drivable route with a predefined length covering all these properties. While the representative road selection may be used for vehicle simulation purposes, the drivable route is needed for real tests. We develop these approaches based on the Virtual Measurement Campaign (VMC) concept in close collaboration between Fraunhofer ITWM in Kaiserslautern and MAN Truck & Bus in Munich.