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Connected and automated vehicles (CAVs) have the potential to eliminate road vehicle collisions and other traffic incidences. Whilst the main motivation for the introduction of vehicular communication systems is to improve safety, they also provide opportunities to reduce CO2 and other harmful pollutant emissions as well as transportation energy costs. Vehicle communication link with other automobiles and Intelligent Transportation Systems (ITS), when combined with the use of on-board high definition navigation maps, enable the vehicle control systems to optimize their operation and streamline traffic flow. This paper presents the development and evaluation of proof of concept control algorithms which optimize the vehicle’s propulsive energy consumption. Consideration is also given to journey time and other drivability and autonomous driving attributes and constraints.

The vehicle dynamics control systems are traditionally based upon utilizing wheel brakes as actuators. However, there has been recently strong interest in the automotive industry for introduction of other vehicle dynamics actuators, in order to improve the overall vehicle stability, responsiveness, and agility features. This paper considers various actuators such as active rear and central differentials and active front and rear steering, and proposes design of related yaw rate control systems. Different control subsystems such as reference model, feedback and feedforward control, allocation algorithm, and time-varying controller limit are discussed. The designed control systems are verified and compared by computer simulation for double lane change and slalom maneuvers.

Wet clutches are widely used in automotive systems. They are essential parts of automatic transmissions, modern All-Wheel-Drive systems or dual-clutch transmissions. Regardless of the area of application, a good knowledge of clutch friction behaviors is crucial for the clutch control system development. This paper considers two important factors of the wet clutch dynamics: coefficient of friction behavior and thermal dynamics. An Active Limited Slip Differential wet clutch with carbon fiber-based friction lining material is experimentally characterized by using a precise wet clutch setup. The characterization of the coefficient of friction behavior includes influence of clutch slip speed, applied force, and friction surface temperature. The clutch thermal dynamics is characterized based on the heat power balance law applied to the clutch separator plate with a variable heat transfer coefficient. The results of the thermal model experimental validation are presented, as well.

Magnetorheological fluid (MRF) clutches are expected to be used in several automotive systems such as auxiliary engine devices, active differentials, and automatic transmissions. An experimental MRF clutch has been developed at the University of Zagreb, in order to support MRF clutch modeling and control research. The paper first presents calculation of the main clutch design parameters and describes the clutch mechatronic system. Next, the clutch static and dynamic behaviors are experimentally characterized. Finally, a model of MRF clutch dynamics is outlined, and characteristic model validation results are presented.

In order to support active limited slip differential (ALSD) modeling work, a test rig of a DC motor-actuated ALSD has been developed. The test rig is equipped with a torque servomotor that provides a precise closed-loop control of the clutch slip speed, as well as with sensors of clutch torque, and DC motor position and current. In addition to the test rig, a precise wet clutch experimental setup has been developed by using the differential hardware. The setup provides direct measurements of the clutch pack axial force, the separator plate temperature, and the press plate axial position. The paper describes the ALSD test rig and the wet clutch experimental setup, presents and analyzes characteristic experimental results, and outlines the main ALSD modeling results.