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The current global chassis control (GCC) frequently makes use of decoupled control methods which depend on driving condition partition and simple rule-based vertical force distribution, and are insufficient to obtain optimal vehicle dynamics performance. Therefore, a novel hierarchical global chassis control system for a distributed electric vehicle (DEV), which is equipped with four wheel driving/steering and active suspension systems, is developed in this paper. The control system consists of three layers: in the upper layer, the desired forces/moments based on vehicular driving demands are determined; in the middle layer, a coordinated control method of longitudinal/lateral/vertical tire forces are proposed; in the lower layer, the driving/steering/suspension control is conducted to realize each distributed tire force.

As one of the most important auto-body moving parts, door hinge is the key point of door design and its accessories arrangement, also the premise of the door kinematic analysis. We proposed an effective layout procedure for door hinge and developed an intelligent system on CATIA CAA platform to execute it. One toolbar and five function modules are constructed - Axis Arrangement, Section, Parting Line, Kinematic, Hinge Database. This system integrated geometrical algorithms, automatically calculate the minimum clearances between doors, fender and hinges on sections to judge if the layout is feasible. As the sizes of the clearances are set to 0s, the feasible layout regions and extreme start/end points are shown in parts window, which help the engineer to check the parting line and design a new one. Our system successfully implemented the functions of five modules for the layout of door hinge axis and parting line based on a door hinge database.

Owing to the small size of engines and high injection pressures, it is difficult to avoid the fuel spray impingement on the combustion cylinder wall and piston head in Direct Injection Spark Ignition (DISI) engine, which is a possible source of hydrocarbons and soot emission. As a result, the droplets size and distribution are significantly important to evaluate the atomization and predict the impingement behaviors, such as stick, spread or splash. However, the microscopic behaviors of droplets are seldom reported due to the high density of small droplets, especially under high pressure conditions. In order to solve this problem, a “spray slicer” was designed to cut the spray before impingement as a sheet one to observe the droplets clearly. The experiment was performed in a constant volume chamber under non-evaporation condition, and a mini-sac injector with single hole was used.

Based on the traditional heavy commercial vehicle, hydraulic hub-motor drive vehicle (HHMDV) is equipped with a hydraulic hub-motor auxiliary drive system, which makes the vehicle change from the rear-wheel drive to the four-wheel drive to improve the traction performance on low-adhesion road. In the typical operating mode of the vehicle, the leakage of the hydraulic system increases because of the oil temperature rising, this makes the control precision of the hydraulic system drop. Therefore, a temperature compensation control strategy for the assist mode is proposed in this paper. According to the principle of flow continuity, considering the loss of the system and the expected wheel speed, the control strategy of multifactor target pump displacement based on temperature compensation is derived. The control strategy is verified by the co-simulation platform of MATLAB/Simulink and AMESim.

Artificial intelligence systems are highly accepted as a technology to offer an alternative way to tackle complex and non-linear problems. They can learn from data, and they are able to handle noisy and incomplete data. Once trained, they can perform prediction and generalization at high speed. The aim of the present study is to propose a novel approach utilizing the adaptive neuro-fuzzy inference system (ANFIS) and the fuzzy clustering method for automotive ride performance estimation. This study investigated the relationship between the automotive ride performance and relative parameters including speed, spring stiffness, damper coefficients, ratios of sprung and unsprung mass. A Takagi-Sugeno fuzzy inference system associated with artificial neuro network was employed. The C-mean fuzzy clustering method was used for grouping the data and identifying membership functions.

Magneto-rhelological(MR) dampers are devices that use rheological fluids to modify the mechanical properties of fluid absorber. The mechanical simplicity, high dynamic range, large force capacity, lower power requirements, robustness and safe manner of operation have made MR dampers attractive devices for semi-active real-time control in civil, aerospace and automotive applications. Landing gear is one of the most essential components of the aircraft, which plays an extreme important role in preventing the airframe from vibration and excessive impact forces, improving passenger comfortable characteristics and increasing aircraft flight safety. In this paper, the semi-active system used in landing gear damping controller design, simulation, and the vibration test-bed are discussed and researched. The MR dampers employed in landing gear system were designed, manufactured and characterized as available semi-active actuators.

Vehicle needs suspension and steering systems with different features to fit different driving conditions. In normal straight driving condition, soft suspension and heavy steering systems are needed to achieve better ride comfort and straight line driving stability; in turning conditions, hard suspension and lightweight steering systems are needed to get better handing stability. The semi-active suspension system with Magneto-Rheological dampers can improve the ride comfort and handling performance of vehicle. Electrical power steering system is developed rapidly due to its portable and flexible operations as well as stable steering performance.

In this paper, a shock absorber physical model is developed. Firstly, a rebound valve model which is based on its structure parameters is built through using the large deflection theory. The von Karman equations are introduced to discover the physical relationships between the load and the deflection of valve discs. An analytical solution of the von Karman equations is then deducted via perturbation method. Secondly, the flow equations and the pressure equations of the shock absorber operating are investigated. The relationship between fluid flow rate and pressure drop of rebound valve is analyzed based on the analytical solution of valve discs deflection. Thirdly, an inter-iterative process of flow rate and pressure drop is employed in order to adequately consider the influence of fluid flow on damping force. Finally, the physical model is validated by comparing the experimental data with the simulation output.

The performance parameters of torsional vibration damper, including stiffness and damping, have great influence on the torsional vibration of automobile driveline. At present, the research on torsional vibration damper mainly concentrates on the torsional stiffness, but rarely on the torsional damping characteristics. This paper systematically studied the effect of torsional stiffness and damping on torsional vibration of automobile driveline under uniform speed conditions, accelerated and decelerated conditions, idling conditions and resonance conditions. The requirements on stiffness and damping of various operating conditions were summarized. The effect and requirements researched were useful to performance match design of torsional vibration damper.

The non-conventional diesel nozzles have attracted more and more attention for their ability to promote jet breakup. In the present study, the internal nozzle flow and jet breakup relying on the convergent-divergent nozzle are investigated by combining the cavitation model and LES model with Multi-Fluid-Quasi-VOF model based on the OpenFOAM code. This is a novel method for which the interphase forces caused by the relative velocity of gas and liquid can be taken into account while sharpening the gas-liquid interface, which is able to accurately present the evolution processes of cavitation and jet breakup. Primarily, the numerical model was verified by the mass flow rate, spray momentum flux, discharge coefficient and effective jet velocity of the prototype Spray D nozzle from the literature.

Electro-Hydraulic Brake (EHB) system is a kind of active control brake systems of automobile, the pedal from the calipers actuation separated and no longer limited by conventional hardware. The system may come together with ABS, ESP, and ASR function, also the communication with other systems is done via the CAN network. EHB system may be classified a “stepping stone” technology to full brake-by-wire and brings huge transform for the performance of braking system. In this paper, vehicle dynamic models were established and accomplished the control strategy for vehicle stability control with EHB system which can adjust wheel and vehicle motion, improve the lateral and longitudinal vehicle stability. This result was verified by simulation which shows that the controller is effective on improving the vehicle stability.

Gasoline detergency is related to deposits at various parts of the engine and therefore has impact on vehicle driveability and emission properties. The widely used engine tests such as CEC F-20 M111 and ASTM D6201 Ford 2.3L tests take tens of hours and thus are very expensive and time consuming to carry out. A new simulation test for gasoline detergency on intake valve cleanliness using lean-oxygen gum method was developed and the correlation of test results with M111 engine test was studied. Gasoline samples with different detergency levels were tested with both the lean-oxygen gum method and the M111 engine test. Test results of 24 gasoline samples show satisfactory correlation between the lean-oxygen gum method and the M111 engine test (R₂=0.7258).

Embedded bus monitoring and fault diagnosis system, which was used on the hybrid vehicle was designed in this paper. And this system took the 32-bit embedded one as a hardware platform, customized a WinCE6.0 operation system and used EVC as the tool to design the embedded application. The functions of CAN communication, protocol defamations etc were realized. Good human-computer interaction is developed and the system has already been applied on the bus.

Air spring has a variable stiffness characteristic, its vibration frequency is much lower than that of leaf spring and will not vary with load of vehicle. More and more air springs are applied on automobile suspension. A study on the automobile ride comfort, and the controllability and stability about the bus with air suspension is performed in the paper, which is based on multi-body system dynamics.

A multitude of recent studies are suggestive of the EV as a paramount representative of the NEV, its development direction is transformed from “individuals adapt to vehicles” to “vehicles serve for occupants”. The multi-mode drive control technology is relatively mature in traditional auto control sphere, however, a host of EV continues to use a single control strategy, which lacks of flexibility and diversity, little if nothing interprets the vehicle performances. Furthermore, due to the complex road environment and peculiarity of vehicle occupants that different requirement has been made for vehicle performance. To solve above problems, this paper uses the key technology of mathematical statistics process in MATLAB, such as the mean, linear fitting and discrete algorithms to clean up, screening and classification the original data in general rules, and based on short trips in the segments of kinematics analysis method to establish a representative of quintessential driving cycle.

To improve traditional heavy commercial vehicles performance, this paper introduces a novel hydraulic hub-motor auxiliary system, which could achieve auxiliary driving and auxiliary braking function. Firstly, the system configuration and operation modes are described. In order to achieve coordinating control and distribution of the engine power between mechanical and hydraulic paths, the paper proposes an optimal algorithm based on enhance of vehicle slip efficiency and the results show that displacement of hydraulic variable pump relates with the transmission gear ratio. And then the hydraulic pump displacement controller is designed, in which the feedforward and feedback strategy is adopted. Considering the characteristics of hydraulic hub-motor auxiliary system, a layered auxiliary drive control strategy is proposed in the paper, which includes signal layers, core control layers and executive layers.

In this paper, analysis methods for brake squeal including substructure modal composition analysis and substructure modal parameters sensitivity analysis are presented. These methods are based on a new closed-loop coupling disc brake model, where the coupled nodal pairs in each coupling interface are connected tightly. This assumption is different from other existing models in literatures, where the interface nodes are coupled through assumed springs. Based on this new model, two analysis methods are derived: Substructure modal composition analysis indicates the contribution of modes of each substructure to the noise mode; Substructure modal parameters sensitivity analysis indicates the sensitivity of the real part of system’s eigenvalue to component’s modal frequency and shape. Finally, the presented analysis methods are applied to analyse a high frequency squeal problem of a squealing disc brake.

This study presents a hybrid optimization approach of TOPSIS-based Taguchi method and entropy measurement for the determination of the optimal suspension parameters to achieve an enhanced compromise among ride comfort, road friendliness which means the extent of damage exerted on the road by the vehicles, and handling stabilities of a self-dumping truck. Firstly, the full multi-body dynamic vehicle model is developed using software ADAMS/Car and the vehicle model is then validated through ride comfort road tests. The performance criterion for ride comfort evaluation is identified as root mean square (RMS) value of frequency weighted acceleration of cab floor, while the road damage coefficient is used for the evaluation of the road-friendliness of a whole vehicle. The lateral acceleration and roll angle of cab were defined as evaluation indices for handling stability performance.

A novel torque-coupling architecture for hybrid electric vehicles is proposed. The torque-coupling device is based on automated manual transmission (AMT), which is highly efficient and provides six gears for the engine and three gears for each motor to enable the engine and the motors to work at high-efficiency levels in most cases. The proposed power-shift AMT (P-AMT) does not have a hydraulic torque converter and wet clutches, which dampen the driveline shock. Thus, the drivability control of the P-AMT becomes a challenging issue. Accurate engine, motor model and transmission model have been built and the dynamic control of the gear shift process of PAMT in hybrid mode is simulated. The electric motors compensate for the traction loss during the gear shift of the engine.

Gear transmission is widely used in mechanical transmission system and acts an important role in automotive industry. Manufacturing errors, assembly looseness, gear wear issues may result in gear backlash, noise and fatigue damage seriously affecting efficiency and service life of gear transmission. For gear transmission assembled, it is important to monitor the conditions of gear meshing and prevent the occurrence of dangerous situations. How to define the issues of gear tooth wear, misaligned bearing, gear eccentricity, backlash, and how to find faulty planetary gear sets and specific issues existing in gear transmission are meaningful and significant to ensure the quality of product. This paper starts from the analysis on gearing mechanism. Based on the behaviors represented by the issues, gear tooth wear, misaligned bearing, gear eccentricity and backlash are demonstrated and explained in detail.