VEHICLE DYNAMICS MANAGEMENT – BENEFITS OF INTEGRATED CONTROL OF ACTIVE BRAKE, ACTIVE STEERING AND ACTIVE SUSPENSION SYSTEMS

摘要

Active chassis systems increasingly take place in market. Beside the well known ESP/EHB braking systems, the significant steering systems are Active Front Steering (AFS), Electric Power Steering (EPS), Rear Wheel Steering (RWS) and, in the future, Steerby- Wire (SbW). Relevant suspension systems are Air Suspension (AS), Continuous Damper Control (CDC), Active Roll Control (ARC) and Active Body Control (ABC). Each of these chassis systems has its own basic functions (e.g. CDC: damping of body motion, AFS: steering support). In addition, there are global functions for vehicle dynamics control: not only ESP, but also active steering systems and active suspension systems can be used for vehicle dynamics control as well. In our contribution, we present an approach for integrated vehicle dynamics control comprising ESP, Active Front Steering and Active Roll Control. In our concept, the active chassis systems act as “smart actuators” with their own decentralized basic functions and interfaces to a central vehicle dynamics controller. Based on this integrated architecture, vehicle characteristics influencing driving behaviour can be adjusted appropriately to different driving situations and different drivers’ characters, and they allow the car manufacturers to brand vehicle behaviour by software. Making use of the synergies arising from the integrated approach, vehicle dynamics are improved concerning comfort, handling, and safety as well. The concept has been developed and proven both by simulation and driving tests in a test vehicle. The test vehicle is equipped with a Bosch ESP system, with AFS and ARC. The chassis systems AFS and ARC have been implemented in a rapid prototyping environment. In driving tests, the vehicle behaviour has been subjectively and objectively assessed. In our paper, the concept and the functions are described, and benefits are shown by measurement results.