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The integrated control between the vehicle chassis subsystems (suspension, brake, and steering) became one of the most important aspects for current developments to improve the dynamics of the vehicles. Therefore, the aim of this study is to investigate the influence of the preview control of the active suspension on the vehicle ride and braking performance. The vehicle performance was examined theoretically using a longitudinal half vehicle model with four degrees of freedom considering the rotational motion of the tires. The active suspension system model, tire-road interface model and braking system model are included in the vehicle model. In order to study the influence of the preview control on the vehicle ride and braking performance, an active suspension system control algorithm employing the lock-ahead preview information and the wheel-base time delay based on the optimal control theory is derived.

Due to the importance of the fast transportation under every circumstance, the transportation process may require a high speed heavy vehicle from time to time, which may turn the transportation process more unsafe. Due to that fact the truck safety during braking and the ride comfort during long distance travelling with high speeds should be improved. Therefore, the aim of this work is to develop a control system which combines the suspension and braking systems. The control system consists of three controllers; the first one for the active suspension system of the truck body and cab, the second one for the ABS and, the third for the integrated control system between the active suspension system and the ABS. The control strategy is also separated into two strategies.

The aim of this study is to create an integrated controller between the active suspension system and an anti-lock braking system using fuzzy logic control theories to improve braking performance. Also, the ride performance during braking is investigated. Braking and ride performances for active are evaluated using half vehicle model. The suspension system, tyre-road interface and anti-lock braking system model are included in the model. The anti-lock braking system and active suspension is compared with the anti-lock braking system combining passive suspension. The simulation result obtained show that the active and ABS system with integrated controller reduces the braking time and distance in the range from 3% to 5% compared with the same system without integrated controller. Furthermore, anti-lock braking system and active suspension improves ride comfort and safety in vehicles compared with passive system.

The paper deals with a theoretical study to present a new sort of the buses suspension systems employs a hydraulic connection between the front and rear dampers together with active suspension actuator at the front axle. The theoretical investigation based on a half vehicle model of the bus suspension system includes the engine mounting system. The hydraulic connection between the front and rear dampers is created according to the capillary tubes theory. Furthermore, the active suspension system control algorithm based on the optimal control theory is derived. The Genetic Algorithm optimization routine is applied to generate the active suspension control algorithm parameters. A comparison between the connected dampers suspension system, active suspension system, active-connected dampers suspension system, and the passive suspension system in terms of ride comfort and road holding at constant suspension working space is performed.

The objective of this study is to develop a Model Reference Control (MRC) strategy for active suspension System. The MRC strategy employs both the suspension look-ahead preview and wheelbase preview concepts, and the methodology of the MRC based on the ideal hybrid skyhook-groundhook concept. The study performed using a 13 degree-of-freedom (DoF) vehicle vertical dynamics model including the active suspension actuators masses. The engine mass, driver seat and anti-roll bar are considered in the model. The MRC strategy uses eight Proportional-Integral-Derivative (PID) controllers for both body and wheel control. A gradient-based optimization algorithm is applied to obtain the controller parameters using a cost function including both ride comfort and road holding performance.