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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.

Current innovations in the area of power train engineering for cars are generating significant and unprecedented challenges for the development of acoustically unobtrusive transmissions. As regards relevance for customers, noise phenomena caused by loose parts play a key role. Transmission rattle, whose primary trigger is the pulse-like torque output of conventional combustion engines, also falls into this category. Current trends within the engine development (e.g. down speeding and downsizing) generate significant challenges for the development of acoustically unobtrusive transmissions. The aim of the presented approach is the evaluation and optimization of transmissions regarding the gear rattling noise perceived by the customer/passenger inside the vehicle. The investigation is divided into several experimental parts. The sound characteristics of the perceivable rattling noise is determined and evaluated as well as the transfer of rattling noise into the passenger compartment.

Powertrain control strategies achieving high performance and better shift control depend critically on the available measurements taken directly from the sensors. For Dual Clutch Transmission (DCT), the clutch friction forces are very important to improve the shift quality. So the estimations are needed to be able to set up the shift control on the powertrain system. For better shift comfort, accurate information for the dual clutch transmission should be available to control the clutch pressure. Furthermore, torque sensors for rotating shafts cannot be used on production vehicles since they are expensive and enduring in the environment of the automotive system. This paper presents an Improved Proportional Integral (IPI) observer for estimation of the unknown forces acting on the clutch during shift processes as well as the non measured states. The estimated unknown forces can be used for the closed-loop control of the dual clutch transmission for better shift quality.