Evaluation of Active Damping for Reduction of Noise, Vibration and Motion of Ground Vehicles by Multibody Simulation

Abstract

Military (and also civil) off-road vehicles are subject to large vibrations which can have severe affects on drivers, crew and load. Ride quality is influenced by vehicle vibrations, which may be induced by a variety of sources including roadway roughness or off-road terrain, or they may be internally generated forces produced by vehicle subsystems, such as the engine, or the suspension mechanisms of weapons. Both short but high vibration peaks as well as long-duration, high frequency vibrations can pose either disorientation and safety problems or a health threat to passengers of a vehicle. Most ground vehicles are equipped with passive spring and damping devices which have reached a high level of sophistication. However, they can usually only be tuned to a good performance in a relatively small operational range (weight, speed, excitation level) or they perform only moderately well over a wide operational range. Semi-active suspension based on dampers, a concept also known as active damping, has reached production stage for luxury vehicles, trucks and trains, and has been proposed for military vehicles such as light armoured vehicles. It has proven to be an effective way to cope with a number of conflicting requirements, especially comfort, ride handling, ground contact of the tire, road friendliness, and it works well for a wide range of applications and over a large operational range. Multibody simulation is a widely accepted method from the evaluation of the potential of active suspension concepts by simulation to the set-up of virtual prototypes of vehicles. The paper will give an overview over active damping techniques, present some state-of-the-art approaches for control and actuation, especially in coordination with other active chassis control approaches, and given examples of applications for ground vehicles.