Evolution of Electronic Control Systems for Improving the Vehicle Dynamic Behavior

Starting with ABS (Antilock Brake System) the steps towards integrated active safety systems dealing with vehicle dynamics is shown. While ABS and TCS were initially designed as open loop controllers for the lateral vehicle motion a first approach towards closed loop control of the lateral vehicle motion for active safety systems was realized by ESP (Electronic Stability Program. Estimation algorithms and model following control are used with ESP to compensate for the lack of sensors. Since 2001 ESP is available for cars with an electro hydraulic brake system. The extension of ESP in combination with active front steering is expected to enter the market in 2003.