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New developments in road profile measurement systems and in semi-active damper technology promote the application of preview control strategies to vehicle suspension systems. This paper details a new semi-active suspension control approach in which a rule-optimized Fuzzy Logic controller is enhanced through preview capability. The proposed approach utilizes an optimization process for obtaining the optimum membership functions and the optimum rule-base of the preview enhanced Fuzzy Logic controller. The preview enhanced Fuzzy Logic controller uses the feedforward road input information and the feedback vehicle state information as the controller inputs. An eleven degree of freedom full vehicle model, which is validated through laboratory tests performed on a hydraulic four-poster shaker, is used for the controller synthesis.

Following the developments in controlled suspension system components, the studies on the vertical dynamics analysis of vehicles increased their popularity in recent years. The objective of this study is to develop a semi-active suspension system controller using Adaptive-Fuzzy Logic control theories together with Kalman Filter for state estimation. A quarter vehicle ride dynamics model is constructed and validated through laboratory tests performed on a hydraulic four-poster shaker. A Kalman Filter algorithm is constructed for bounce velocity estimation, and its accuracy is verified through measurements performed with external displacement sensors. The benefit of using adaptive control with Fuzzy-Logic to maintain the optimal performance over a wide range of road inputs is enhanced by the accuracy of Kalman Filter in estimating the controller inputs. A gradient-based optimization algorithm is applied for improving the Fuzzy-Logic controller parameters.

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 current paper addresses the relationship between the damper top mount characteristics and the ride comfort and harshness of a vehicle. A detailed mathematical damper top mount model which can simulate the vertical force characteristics of damper top mounts is developed and verified with actual tests. The amplitude and frequency dependent parameters of the damper top mount model are extracted from experimental testing of a commercial damper top mount. In order to identify the model parameters, a new procedure based on a two-stage optimization routine using two sets of measurement data for the amplitude and frequency dependent parameters is proposed. The damper top mount model is validated by comparing the measured force of the damper top mount with the simulated force of the proposed model. The developed top mount model is then implemented into a quarter vehicle simulation model for studying the influence of damper top mount characteristics on vehicle ride comfort and harshness.

Hybrid electric vehicle (HEVs) represents a promising approach to reduce vehicle fuel consumption and exhaust emissions. However, due to the electric motor (EM) assistance, the engine load could be reduced and intermittent operation of engine is realizable in HEVs powertrain system. Consequently, the HEV powertrain heating-up process and engine fuel consumption will be changed accordingly. Therefore, the influences of the EM power and battery capacity on the hybrid powertrain heating-up process and the engine fuel consumption will be analyzed, and 2 methods for optimizing the heating-up process by applying the auxiliary heaters (AHs) and the modification of the energy management strategy are represented. The application of AHs can improve engine efficiency during heating-up; the controlling of the power flow from the AHs to the ICE cooling system is of special important.

Semi-active suspension offers variety of damping force range which demands greater need to optimize the top mount to ensure multiple objectives of ride comfort, harshness and safety can be achieved. For this purpose, this paper proposes a numerical optimization procedure for improving the harshness performance of the vehicle through the adjustment of the damper top mount characteristics of the semi-active suspension system. The proposed optimization process employs a frequency dependent combined objective function based on ride comfort and harshness evaluation. A detailed and accurate damper top mount mathematical model is implemented inside a validated full vehicle model to provide a realistic simulation environment for the optimization study. The semi-active suspension system employs a Rule-Optimized Fuzzy-Logic controller. The ride comfort and harshness of the full vehicle are evaluated by analyzing the body acceleration in different frequency ranges.