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A 3D finite element (FE) model of a radial tire 205/55R16, established using ABAQUS software, is utilized to simulate tire force and moment properties. Drum tests are designed to validate the FE model’s reliability. To investigate the impacts of PCR contour design theory on tire force and moment, a modified string balance contour theory is presented. Based on string balance contour theory, it simplifies the shape of belt pressure share ratio as a trapezium. Besides, a program for calculating tire contour curve is compiled using MATLAB software. Applying different belt pressure share ratios, diverse tire contours are designed. One of the contours is selected according to its positive effect on cornering stiffness in simulation.

This paper proposes an optimal method for the air suspension linkages design, which takes multiple critical geometric dimensions of the linkage as design variables, takes the maximum stress of critical areas in certain parts and the total mass of the assembly as objective functions, normalizes those objectives, and combines them together to evaluate the design. A design flow is developed to integrate the proposed method with a 3-D modeling software and a finite element software, and to expedite the design process. The effect of design variables on the stress of each part and on the mass is analyzed. Based on the sensitivity analysis and the objectives' values, the best design is determined from several available candidate schemes. The stress at critical areas is decreased significantly, as well as the total mass, which improve the safety and cut the cost. The optimization method is also applicable to any multi-parameter multi-objective mechanical part design.

Taking the five-link suspension of a car as the subject investigated on the basis of ADAMS/Car, this paper builds the parameterized mode of the multi-link suspension. The simulation shows the influence relations among multi-link suspension structure parameter and the wheel location parameter, wheel track, roll center. On the base of this, aim for improving the ride safety and comfort, multi-link suspension optimization model is built and carried out parameter optimization design by using ADAMS/Insight. The result shows that this method is high-performance and can be used in the design of multi-link suspension conveniently.

Aiming at the problem of braking shock caused by the inconsistent response time of the inner motor (IM), the outer motor (OM) and the hydraulic brake when the regenerative braking mode of dual-rotor in-wheel motor (DRIWM) is switched, this paper proposes a U-shaped transition coordinated control strategy for the DRIWM. Ensure that the total braking torque can be smoothly transitioned when any one or more of the hydraulic braking torque, the braking torque of the IM and the braking torque of the OM enter/exit braking. The dynamic model of electric vehicle (EV) with DRIWMs is established, the division of braking mode is based on the principle of optimal DRIWM system efficiency, and the U-shaped transition coordinated controller of DRIWM is designed. Finally, two cases of switching the IM single braking mode to hydraulic braking mode and OM and hydraulic coordinated braking mode switching to compound braking mode are taken as examples to verify.

In view of friction braking consumes the kinetic energy of the car by converting it into heat energy, it cannot recover this part of energy. And compared to electric braking, its braking response is slower. An integrated braking system of electromagnetic braking, regenerative braking and friction braking of in-wheel motor is proposed.

Interconnected air suspension system can change a vehicle’s operation characteristics by exchanging gas between air springs. In this paper, we analyze the structure and working principle of interconnected air suspension based on thermodynamics and vehicle dynamics. Then air suspension’s mathematical model including interconnected characteristics is established to study gas exchange principle of air suspension system. Interconnected pipeline parameters and excitation phase differences’ influence on characteristics of air suspension system in whole vehicle are calculated and analyzed. Simulation results show that the stiffness of air suspension is reduced when air springs of the suspension system are interconnected, as well as it decreases gradually with the increase of interconnected pipeline diameter; the stiffness of air springs is minimum if the excitation phase difference between both sides of air springs is 180 degrees.

With the rise of intelligent transportation systems around the world, research on automobile active safety technology has gained widespread attention. Autonomous Emergency Braking (AEB) which can avoid or mitigate collision by active braking has become a hot research topic in the field of automobile. However, there are some limitations in the present AEB collision avoidance strategy, including lack of effective identification of road adhesion conditions, mismatch of active braking system parameters and imperfection of target vehicle motion information, which leads to poor collision avoidance performance on low adhesion coefficient road surface and intervention with the normal driving operation of the driver. A new collision avoidance strategy for AEB is proposed in this paper.

For coordinating the ride comfort and driving safety, the “inerter-spring-damper” (ISD) system is proposed in this paper, and the “spring-adjustable damper” is adapted to connect with ISD in series, then, a new type of semi-active suspension system is established. In order to verify the system rationality, the ISD semi-active suspension model and robust controller model are established respectively in the AMESim and MATLAB/Simulink environment, which is based on two degrees of freedom suspension model. Then, the co-simulation of ISD semi-active suspension with robust control is analyzed. Compared with the conventional ISD suspension, the results show that, the ISD semi-active suspension with robust control can significantly reduce the body vertical vibration, restrain tire resonance and enhance the tire grounding, that is, this system can coordinate the conflicts between vehicle ride comfort and driving safety.

An elliptical influence model of obstacle vehicles was proposed based on the artificial potential field method. The novel mathematical model of lane changing trajectory planning including the lane boundary potential field, the multi obstacle vehicles potential field and the moving target potential field was established to simulate the trajectory planning of intelligent vehicle lane changing under the actual freeway scene. The result shows that the planning trajectory is highly consistent with real one under good lane changing conditions. Furthermore, this kind of the trajectory was introduced into CARSIM software and simulated. The findings show that the actual trajectory is also consistent with the target trajectory. Both the front wheel steering angle and the lateral acceleration were satisfied with the dynamic constraint of vehicle, which has well stability and comfort.

In China, although overload phenomena are serious and effective transportation management is urgently demanded, equipment mainly used to check overloads is platform scales for static weighing. To develop an effective and economical Weigh-In-Motion (WIM) system is imperative in China. With this awareness, we presented a new technology, using high-pressure oil pipe as the sensor of the WIM system. By acquiring and analyzing the pressure signals when vehicles run over the pipe, the wheel loads, axel loads and gross weight can be got. In this paper, the static characteristics and dynamic characteristics of the oil pipe have been researched, and the system's hardware and software were developed. Considering complicated characteristic of the oil pipe and other factors effecting WIM precision, we used neural networks to scale the WIM system dynamically. Test results showed that precision can satisfy the requirement of actual application.

The math model of united brake system is set up on thinking of the influence of the coefficient of the revolving mass changes to linear mass of vehicle, the efficiency of slippage and so on. The simulation model is set up in the Simulink module of Matlab. The result of simulation shows that the braking distance is shortened by the function of united brake system in the emergency brake; the braking ability of the bus is improved. The united brake system can also be used to stop the bus in the nonemergercy brake. The retarder exhausts most of energy of automobile. Thus, the maintenance cost is reduced. The bus can run at steady and economic speed on the hillside path with continuous brake of united brake system.

In order to improve the driving safety, an integrated brake system of trailers is proposed, which can solve the problems of insufficient braking force and poor stability when braking. This system realizes the integration of the main braking system and the auxiliary braking system of articulated vehicles, thus avoiding the phenomenon of "folding" and "rollover" during braking. The integrated brake system developed in this paper is mainly composed of friction braking system and electromagnetic braking system. First, the design scheme for the integrated brake system was illustrated based on the system’s working principle and structures. After that, the mathematical model of electromagnetic braking system was derived based on electromagnetic theory. Then, the electromagnetic braking system was simulated by CAE technology, while the magnetic density distribution and braking torque value were studied.