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The control of automotive braking systems performance and wheel slip is a challenging problem due to the nonlinear of the braking process, vehicle body dynamics during braking and the tire-road interaction. When the wheel slip is not between the optimal limits during braking, the desired tire-friction force cannot be achieved, which influences the braking distance, the loss in steerability and maneuverability of the vehicle. A simple and at the same time realistic vehicle longitudinal braking model is essential for such challenging problem. In this paper, a new longitudinal rolling/braking lumped-vehicle model that takes vehicle aerodynamic forces in consideration is presented. The proposed model takes the rolling resistance force, the braking force and the aerodynamic lift and drag forces in consideration and investigates their impact on the vehicle longitudinal dynamics especially vehicle braking distance and time.

Dry clutch control is one of the main components of both conventional and advanced automotive powertrain systems. In this paper, a robust control strategy is proposed which is suitable for the precise and accurate control of a clutch-by-wire actuator in automotive applications. A parallel connection of a sliding mode controller to a proportional integral derivative (PID) controller collectively forms the proposed robust controller. The sliding mode controller alone ensures robust control against system nonlinearities by providing a high feedback gain, but it also induces a control chattering phenomenon which could be harmful for the clutch-by-wire actuator. Instead of viewing chattering as an undesirable yet inevitable feature, the chattering signals are used as natural excitation signals for identifying an equivalent PID controller using the recursive least squares algorithm. Analysis is provided on the robustness properties of the control scheme.

The vehicle dynamics and controls play a significant role in vehicle handling performance characteristics. The control of vehicle braking system and wheel slip is a challenging problem due to the nonlinear dynamics of the braking process and the wheel-road interaction. A simple and at the same time realistic vehicle longitudinal braking model is essential for such a challenging problem. In this paper, a new longitudinal rolling/braking quarter-vehicle model is presented. The proposed model takes both the rolling resistance force and the braking force into consideration and investigates their impact on the vehicle longitudinal dynamics. An anti-lock sliding-mode controller is designed to provide wheel slip control during vehicle motion. This type of controller is chosen due to its expected robustness against varying road friction coefficient.

In this paper, an optimal control tracking strategy for a brake-by-wire system is developed and tested on a laboratory setup consisting of a driving motor, clutch and gearbox system, rotating inertia and an electro-mechanical brake actuator. The presented brake by wire system consists of a brake pedal sub-system connected to the electro-mechanical brake actuator through an electronic control module handling the optimal control logic. A mathematical model of the proposed brake-by-wire control system is presented. The presented mathematical model is simulated and validated against the experimental data. The good agreement between both simulation results and experimental validates the mathematical model. The validated mathematical model is then used to test the proposed optimal control tracking strategy against different levels of disturbances that are difficult to emulate in the laboratory.

Dry Clutch is one of the main components of both conventional and advanced automotive powertrain systems. Dry Clutch Control has a key role in ride comfort during standing-start and gear-shifting maneuvers. Vehicle shift performance and powertrain torque interruption are of key interest to the control problem. A faster shift time results in a more responsive vehicle but at the same time induces high level of powertrain torque interruption and vise versa. This is due to the high nonlinear behavior of the slip dependent friction torque of the vehicle's dry clutch. In this paper a dual mode control strategy for the dry clutch-by-wire system is proposed. The nonlinear behavior of the clutch friction torque is classified into two regions, a nonlinear region at a low level of clutch slip and a linear region at a high level of clutch slip. The presented control strategy switches between adaptive proportional control in the linear region and sliding mode control in the nonlinear one.

A vehicle braking system is used to provide acceptable drivability of the vehicle and ensure safety in different emergency situations that the vehicle may encounter. The braking system is used also as an integrated sub-system in many other important vehicle driving systems such as traction control, adaptive cruise control, accident avoidance and other vehicle systems in which the braking system plays an important role. This paper is dedicated to provide an accurate and at the same time simple enough hydro-mechanical braking system mathematical model that takes brake pad wear impact on the system pressure dynamics into consideration. A wear simulation procedure based on the concept of Archard's wear law is used and integrated in the nonlinear braking system model with flow compressibility taken into consideration. The presented model simulation results and the experimental tests results show good agreement and validate the confidence in the proposed model.