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To solve the dynamic response problem that contains uncertain parameters needs, the stochastic differential equations needs to be calculated. Interval analysis has been widely used to solve engineering problems which contain many uncertain parameters usually. But the numerical solution method for stochastic differential equations based on the interval analysis method was seldom investigated. In this study a new numerical interval method for the stochastic differential equations based on the Euler's method is presented, which can be used to solve the linear system effectively and efficiently. The probabilistic and interval dynamics analysis of a two-degree-of-freedom bike car model with uncertain parameters are presented.

Hydraulic power steering system, which can reduce the steering hand force by applying the output from a hydraulic actuator, has been widely used in vehicles. In this paper, a detailed steer model including steering column, steering trapezium, and detailed hydraulic power steering system which is consisting of steering cylinder, relief valve, rotary valve, pump and hydraulic lines were established, and a multi-body model of a heavy truck was established to connect with the hydraulic power steering system. Modelica simulation language, which can be efficiently used to investigate multi-domain problems, was used to in the modeling and simulation of the power steering system and the vehicle. The simulation was carried out to identify the effects of design variables on the lateral stability of the vehicle. The application of Modelica for investigating multi-domain problems is also demonstrated.

Hydraulic systems are popular on vehicles, such as power steering, shock absorbers, brakes, etc. Many previously works have been done on the modeling and simulation of the hydraulic systems. However, these models and parameters are usually established on the basis of plans, drawings, measurements, observations, experiences, expert knowledge and standards, and so on. In general, certain information and precise values do not exist. Uncertainty may result, e.g., from human mistakes and errors in the manufacture, from the use and maintenance of constructions, from expert evaluations, and from a lack of information. Actually, many uncertain factors will lead to great errors, and may have great effect on the hydraulic system, so the research on the hydraulic system under uncertainties is very necessary. In this paper, fuzzy algorithm is introduced to analysis the response of the hydraulic system with uncertain parameters.

The automatic mechanical transmission (AMT) was designed by automobile manufacturers to provide a better driving experience, especially in cities where congestion frequently causes stop-and-go traffic patterns. It uses electronic sensors, processors, hydraulic or pneumatic actuators execute clutch actuation and gear shifts on the command of the driver. Such systems coupled with various physical domains have great influence on the dynamic behavior of the vehicle, such as shift quality, driveability, acceleration, etc. This paper presents a detailed AMT model composed of various components from multi-domains like mechanical systems (clutch, gear pair, synchronizer, etc.), pneumatic actuator systems (clutch actuation system, gear select actuation system, gear shift actuation system, etc.). Various components and subsystem models, such as the vehicle, engine, AMT, wheels, etc., are integrated into an overall vehicle system model according to the transmission power flow and control logic.

Due to the influence of non-linear dynamic characteristic of clutch, time-delays, external disturbance and parameter uncertainty, it is difficult to control the automated clutch precisely during the engaging process of the automated clutch for automatic mechanical transmission (AMT) vehicles. Here, an enhanced fuzzy sliding mode controller (EFSMC) has been proposed to control the automated clutch. To meet the real-time requirement of the automated clutch, the region-wise linear technology is adapted to reduce the fuzzy rules of the EFSMC. The simulation results have shown that the proposed controller can achieve a higher performance with minimum reaching time and smooth control actions. In addition, it shows that the controller is effective and robust to the parametric variation and external disturbance.

Clutch actuation systems are complex systems where hydraulic, pneumatic, mechanical and electrical components are coupled. This paper presents a detailed clutch actuation model composed of components from multi-domains like mechanical and pneumatic actuation system, hydraulic boosting system, etc. Various components and subsystem models, such as the driver, engine, gear pairs, clutches, etc., are integrated into an overall vehicle system model according to the transmission power flow and control logic. The model is implemented using the Modelica programming language. The simulation of the clutch actuation system was carried out for the analysis of drivability, shift quality and vehicle overall performance.