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In this paper, nanodiamond films (NDF) were prepared on glass substrate by screen printing with nanodiamond. The NDF was printed with two layers and treated with different surface treatments.The field emission model of nanodiamond thin film was established. Field Emission of different Ratio was studyed. The mechanism by which the field emission characteristics of nanocrystalline diamond films are improved was analyzed.

Increasing consumption of the automobile make vehicle seat comfort characteristic paid more attention to. Damping performance as the third important factors is not allowed to ignore. A three freedom "human - seat" system model has been created for simulation. The result show that as the natural frequency f0 improved, the two resonance peak frequency of the system also improved, the growth of the first order resonance frequency is quite obvious, the second is less growth. And the higher the f0 the less change is. With the improvement of f0, the first order resonance peak to peak value obviously reduced, and the second order resonance peak to peak value increased. So, it is said that the higher the f0 the poor damping effect in high frequency area. The influence of ξ for the damping ratio of work frequency is not big, but the influence for the amplitude value is significant. Increase the natural frequency can make phase angle decreased when resonance, but the change of damping ratio, do not have obviously changes.

The investigations about vehicle crossing process mainly use numerical simulation methods and, moreover, the relevant investigation is quite less. In this study, a three- dimensional fluid simulation model was established. By moving mesh technique, the three- dimensional transient simulation for vehicle crossing process was finished. The aerodynamics characteristics of vehicle crossing process with different lateral interval distances were analyzed. The analytical results show that the smaller the lateral interval distance, the more the transverse thrust between two vehicles during the crossing process. During the whole crossing process, the lateral force shows itself with repulsion in the beginning and attraction in the end. When the lateral interval distance of crossing is very small, the air disturbance due to crossing not only makes large affection to the lateral force but also influence obviously the positive pressure area of the front car bodywork.

The dynamic index and economic index of battery electric vehicles are mutual related as well as opposite. So they should be evaluated synthetically. From the analysis of literatures, the maximum speed, accelerating ability and driving range are chosen as the synthetic evaluation index. By the method of principal component analysis, the synthetic evaluation model of the dynamic and economic performance of battery electric vehicle is established. And example is used to explain the application of the model.

The characteristics of vibration and noise of an automobile have become important factors for evaluating automobiles. In this study, finite element modal analysis and harmonic analysis were used to analyze the dynamic characteristics of the bus bodywork. The analytical results show that vibration of ceiling board and floor board is large while the engine remains the idle running. The vibration of ceiling board and floor board are large during the engine running with the idle speed or the highest speed. In addition, the vibration of ceiling board and floor board also has peak values during the engine running with the maximum torsion moment. Therefore, for prediction of vehicle bodywork vibration and vehicle interior noise, the influence of the engine vibration on them should be considered in order to avoid resonance of bodywork boards and coupling of bodywork boards and interior acoustic field.

Based on the building of non-stationary road surface excitation mode, a study on the active suspension control under non-stationary running condition was conducted using control, state feedback control strategy for linear systems with time-domain hard constraints was propose. The proposed approach was applied to design active suspension systems on the basis of a two-degree-of-freedom quarter car mode, Simulation results show that the proposed constrained controller can achieve a promising improvement on ride comfort, while keeping dynamic suspension deflections, dynamic tire loads and control forces within given bounds, even non-stationary running.

The steering system of automobiles might vibrate under external excitation loading. Severe vibration of the steering system maybe bring the drivers uncomfortable and even result to noise and damage of some parts of the steering system. In the same time, it can not be satisfied with NVH design requirement of automobiles. In this study a three- dimensional finite element model of a steering wheel of automobiles was established and finite element static and dynamic analyses were conducted in order to validate dynamic characteristics and strength of the steering system. The simulation results can provide a reference for structural design of the steering system.

This paper establishes mathematical model of energy consumption economy for constant speed driving and acceleration driving. According to the model, influence degree calculation formulas of parameter sensitivity of vehicle mass, mechanical efficiency of transmission system, rolling resistance coefficient and air resistance factor to energy consumption economy are proposed, and analysis of energy consumption economy parameter sensitivity on a kind of BEV is conducted.

In this paper, inverse pseudo excitation method for vehicle dynamic load identification is used. When the vehicle is in stationary random vibration, the vehicle dynamic load spectrum recognition problem is solved by using the deterministic method. The auto-PSD and cross-PSD of vehicle vibration response is known. Base on the reversing the power spectrum of road excitation, Vehicle dynamic load PSD is obtained. The results show that, Inverse pseudo excitation method for solving the vehicle dynamic load spectrum has good solution accuracy, put forward new ideas and methods for vehicle engineering practice, and has broad application prospects.

This paper gives the evaluation method of the design scheme of power transmission system and builds the evaluation index system and fuzzy comprehensive evaluation model based on the index of dynamic property and energy consumption economy of battery electric vehicle. And the evaluation index system and evaluation model can be used to provide basis for the decision of the design scheme.

Traffic accidents cause to a large quantity of personnel casualty and economic loss every year. The safety in vehicle crash has been one of important criterions in vehicle design. In this study a three-dimensional finite element model was established and the front crash process of car bodywork was analyzed. The simulation results show that the structure design of car bodywork is reasonable and of safety for the passengers. The investigation of this study not only validates the rationality of the car bodywork design but also provides a detailed numerical simulation model for further investigation as well as improvement and optimization of the car bodywork structure.

The characteristic of vibration and noise of an automobile has become an important guide line to evaluate an automobile during the development of manufacturing and comfort of automobiles. In this study, finite element modal analysis was used to extract the acoustic resonant frequency and acoustic modal modes. The results show that the influence of vehicle seats on the acoustic modality should be considered in the acoustic design of vehicle interior cavum. Higher acoustic pressure areas for lower acoustic modalities mainly lie at the anterior/posterior ends or middle of the vehicle interior cavum.

The vehicle riding comfort has become one of important factors of vehicle quality and receives more increasing attention. The driving smoothness of vehicles has immediate influence on the riding comfort of vehicles. In this study, the mechanical model and mathematics model of the 1/2 five degrees of freedom of a vehicle were established, as well as the pseudo- excitation model of road conditions for the front wheel and the rear wheel. By the pseudo- excitation method, the equations of the transient response and the power spectral density were established. After numerical simulation to vehicle vibration response of uneven driving, the results show that the pseudo- excitation method is more convenient than the traditional method and effectively solves the smoothness computation of vehicles while the pseudo- excitation method is used to analyze vehicle vibration under non-stationary random vibration.

In this study, we used Cricket equipments based on wireless sensor networks to study the pursuit-evasion strategy of multi-robots in a continuous map. In order to improve the efficiency, two new pursuit-evasion strategies were proposed. To meet the need of a continuous map, a greedy algorithm was utilized to deal with boundary problem when a pursuer or an evader was near the field boundary. The statistical results show the converging-attack pursuit strategy outperforms in pursuing the evader with different escaping strategies, such as randomly moving, active escaping strategy and vector-wards escaping strategy. The vector-wards escaping strategy is also effective in delaying the capture of evaders.

The localization of mobile robots is one of important problems for navigation of mobile robots. The wireless sensor network, i.e., Cricket wireless localization technology, was used to obtain motive condition of mobile objects in this study. The information transmission between the Cricket localization system and mobile robot system was achieved for localization, navigation and control of the mobile object. The errors of localization sampling data of the Cricket localization system vary within 3cm in a static condition. The Cricket localization system can meet the navigation requirement of the mobile robots.

Rollover and jack-knifing of tractor semitrailer on high speed obstacle avoidance under emergency are serious threats for motorists. A tractor semitrailer model was built with multi-rigid-body method in this paper. The steering performance of tractor semitrailer has been analyzed, as well as the stability control theory, including yaw rate following, anti-rollover. The dynamics simulation for yaw rate following and anti-rollover has been performed on the dynamic tractor semitrailer. The results show that the vehicle dynamics control proposed in this paper can stabilize the tractor semitrailer, rollover and jack-knifing are prevented and the tractor semitrailer more accurately follows the driver's desired path.

A there-dimensional finite element model of the working device of a single backhoe-bucket hydraulic excavator was developed to analyze and evaluate the rationality of structure design of the working device in this study. By finite element modal analysis, the resonant frequencies and vibration modes of the working device system were obtained. By dynamic response analysis, the changing trends of stress and strain of the device were obtained. In addition, the influence of different excavating resistance forces to the working device on dynamic response of the device system was compared for large and small resistance forces at the beginning excavation moment. The results show that a large resistance force at the initial excavating moment may result in the device vibrating with large vibration amplitude at the beginning excavation moment. These results might provide useful reference on design improvement of the excavator working device.