Flatness based velocity tracking control of a vehicle on a roller dynamometer using a robotic driver

This paper presents a velocity tracking control of a robotic driver that is used for driving industry test cycles on roller dynamometers. As existing commercial robotic drivers show a high complexity, use outdated mechanics and are nevertheless quite expensive, a new robotic driver is developed. The aim is to track a well defined velocity trajectory of a test cycle with high accuracy in an arbitrary vehicle, whereby no learning cycle for determining the specific vehicle behaviour is allowed. To meet all these conditions, at first a single-wheel model for the longitudinal dynamics of a vehicle is proposed. Additionally, an approximation for the engine torque is given, enabling the adaption of the resulting model by changing only few parameters. Based on this model, a flatness based velocity tracking control for operating the acceleration pedal is introduced.