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As the automotive industry accelerates its virtual engineering capabilities, there is a growing requirement for increased accuracy across a broad range of vehicle simulations. Regarding control system development, utilizing vehicle simulations to conduct ‘pre-tuning’ activities can significantly reduce time and costs. However, achieving an accurate prediction of, e.g., stopping distance, requires accurate tire modeling. The Magic Formula tire model is often used to effectively model the tire response within vehicle dynamics simulations. However, such models often: i) represent the tire driving on sandpaper; and ii) do not accurately capture the transient response over a wide slip range. In this paper, a novel methodology is developed using the MF-Tyre/MF-Swift tire model to enhance the accuracy of ABS braking simulations.

Control of an antilock brake system for aircraft and land vehicles is based upon estimates of the torque applied to braking wheels by means of a sliding mode observer. The observer yields a highly accurate estimate of torque that is robust for the entire operating range of the brakes, and provides an input to a relatively simple control system that regulates applied torque from either an electro-hydraulic or electromechanical actuator. Excellent braking performance for a regional jet transport is demonstrated in this paper via hardware-in-the-loop simulation. A simple scheme for suppressing gear walk (aircraft application) is presented.

Since 1982 Daimler-Benz is the first commercial vehicle and bus manufacturer to offer modern anti-lock systems (ABS). After several years of development, anti-lock systems have technically matured to be installed upon request in vehicles with air brakes. The installation rate of this safety item has been steadily increasing ever since. The fundamental design and control philosophy of 4- and 6-channel anti-lock systems will be described. Besides a global analysis regarding the failsafe quotas of digitized electronics in road vehicles, the ABS-specific components will be looked at. The gain of safety achieved by the installation of ABS in commercial vehicles and buses will be presented with the aid of computer simulation. A 40-t-truck/trailer combination, with ABS, without ABS and with a partially defect system, will serve as an example to demonstrate the dynamic behavior during “Braking in a Straight Line” and “Braking in a Turn”