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Due to the complexity and timeliness of the dual power source control system for range extended electric vehicles, a real-time predictive fuzzy energy management strategy based on speed prediction, which comprehensively takes into account the demand power of auxiliary power unit, future average speed and driving distance is proposed in this work. Firstly, to improve the topicality and accuracy of the control system, the convolutional neural network with long short-term memory neural network (CNN-LSTM) algorithm is adopted to predict the future driving speed by the speed features and adjacent speeds.

In order to achieve a good shifting quality of pure electric vehicle dual-clutch transmission, this paper adopts linear active disturbance rejection controller (LADRC) to control the shifting strategy. For the uncertainty of transmission dynamics model parameters and the existence of unknown disturbance effects, the linear expansion state observer (LESO) can be used to estimate and compensate the disturbance. The shift control process is converted into tracking the motor speed and clutch speed trajectory, and the linear feedback control law is used to control the motor torque and the solenoid valve current. The simulation and test results show that the control algorithm is effective and good shifting quality is guaranteed.

This paper proposes a hybrid carrier spread spectrum modulation (HCSM) technique based on dynamically adjusting the spatial zero-vectors action time to suppress the sideband vibro-acoustic responses introduced by the discontinuous pulse-width modulation (DPWM) in permanent magnet synchronous motor (PMSM) for electric vehicles (EVs). Firstly, the space vector principle of DPWM is presented, and the relationship between current harmonics and space zero-vectors is analyzed. Then, the HCSM technique is proposed to suppress the current harmonics and vibro-acoustic responses based on the variation trend of zero-vectors action time in six sectors, and the suppression effect of HCSM on sideband components is predicted by the finite element method. Finally, with a 12-slots/10-poles prototype PMSM, the sideband vibro-acoustic responses and the electric drive system loss caused by DPWM and classical space vector pulse-width modulation (SVPWM) before and after using HCSM are analyzed.

The sideband current harmonics generated by the voltage source inverter (VSI) and its related space vector pulse-width modulation (SVPWM) method are the main causes of the high-frequency vibro-acoustics responses in permanent magnet synchronous motor (PMSM). In this study, a novel hybrid carrier frequency modulation (HCFM) method based on the modified zero-vector action time of dynamic space is proposed to supress current harmonic, and reduce sideband vibro-acoustics. Firstly, since the zero-vector action time of different space angles can directly affect the current harmonic amplitude, the six traditional spaces are dynamically re-divided into twelve subspaces. Then, the carrier frequency is actively adjusted, according to based on the action-time variation tendency of the dynamic zero-vector in different subspaces for suppressing the current harmonic amplitude. The correlation of the current harmonic power spectral density of the HCFM method is deduced.

Dual Clutch Automatic Transmission (DCT) has the characteristics of light weight, fast shift speed and high transmission efficiency. Electric vehicles equipped with dual clutch transmission can effectively improve vehicle power performance and economy. Electro-hydraulic control system, as a key component of transmission, determines the quality of shift. In this paper, an electro - hydraulic control system is designed based on two - speed dry dual clutch transmission of electric vehicle. Firstly, the hydraulic components of the system were selected and calculated based on the vehicle parameters. Secondly, the electro-hydraulic control system of the dual clutch transmission was established according to the transmission control strategy and the matching hydraulic valve body assembly was designed. Then, the key components of the system were simulated to analyze their dynamic shift characteristics and response characteristics.

In order to improve the path tracking accuracy of driverless vehicles at different speed, a fuzzy adaptive model prediction control method was proposed to adjust constant predictive horizon of MPC. Based on the MPC method of 3-DOF vehicle dynamics model, prediction horizon and weight coefficient of the MPC controller could be varied in real time according to the speed and road curvature. With the desired path as the target, the front wheel angle was changed to achieve path tracking. Simulation analysis was performed under the CarSim/Simulink co-simulation environment. Simulation results show that under the condition of satisfying ride comfort and stability of vehicle, the tracking error of the proposed method in the path tracking control is reduced by 30.0%, 29.9% and 14.6% at 36km/h, 72km/h and 108km/h, respectively, which are helpful to path tracking control.

Electric buses have been used widely as cities' short-range commuter vehicles, because of their excellent power, fuel economy and emission characteristics. However, the lack of a noise masking effect for the traditional internal combustion engine, the high-frequency noise becomes more prominent for the powertrain system. The high-frequency noise gives people an unpleasant feeling on psychological and physiological. To control electric vehicle powertrain noise, the identification of the main noise source of the powertrain is well needed. In this paper, Empirical Mode decomposition (EMD) combined with Independent component Analysis (ICA) and continuous Wavelet transform (CWT) was used to identify the main noise source of the electric bus powertrain. The contribution of each noise source to the overall noise level was calculated and compared.

Because of the advantages of excellent power, fuel economy and zero-emission characteristics, electric buses have been used widely as cities’ short-range commuter vehicles. However, the high-frequency noise becomes more prominent for the powertrain system of the electric bus due to the lack of noise masking effect for the traditional internal combustion engine. To improve the noise characteristic of electric bus powertrain, the identification of the main noise source of the powertrain is well needed. In this paper, the effects of the motor and transmission on the noise level of the electric bus powertrain have been studied using lead packaging method. The variations of acoustical power level of the powertrain according to different rotation speed and torque under the conditions of only motor covered and only transmission covered have been discussed.

In helicopter, the icing rotor blades will decrease the effectiveness of the helicopter and endanger the lives of the pilots. The asymmetrical ice break-up and shedding could also lead to severe vibrations of the rotor blade. Ice break-up from the main rotor may strike the fuselage and tail rotor, even worse, find its way into the engine, which may cause serious aircraft accidents. An understanding of the mechanisms responsible for ice shedding process is necessary in order to optimize the helicopter rotor blade design and de-icing system to avoid hazardous ice shedding. In this paper, the ice shedding model is improved by introducing a bilinear cohesive zone model (CZM) to simulate the initiation and propagation of ice/blade interface crack. A maximum stress criterion is used to describe the failure occurred in the ice.

In order to improve the drivability and reduce the clutch friction loss, low-cost slope sensor is used in hill-start control of AMT vehicles. After the power spectrum analysis of the original signal and the design of the digital filter, the angle of the slope is obtained with short enough delay and small enough noise. By using this slope angle information, slope resistance force can be calculated online so that the vehicle can be prevented from sliding backward and optimal launch control can be realized. The digital filter of slope angle signal and the optimal controller of dry clutch engagement are embedded in the TCU (Transmission Control Unit) of a micro-car Geely Panda. Real-vehicle experiments are carried out with optimal clutch controller, which shows that the hill-start with low-cost slope sensor and optimal clutch controller can provide successful vehicle launch with little driveline shock. In addition, it can also avoid backward sliding and engine over-speed effectively.

The aim of the study was to investigate the difference between car-to-e-bikes and car-to-pedestrian accidents. The China In-depth Accident Study (CIDAS) database was searched from 2011 to 2013 for pedestrians and e-bikes struck by car, van and SUV fronts, which resulted in 104 pedestrian and 85 e-bike cases where information was sufficient for in-depth analysis. Reconstruction by PC-Crash was performed for all of the sampled cases. Pre-crash parameters were calculated by a MATLAB code. Focus was on prototypical accident scenarios and causes; speed as well as possible prevention countermeasures. It has been shown that traffic light violations, road priority violations, and unsure safety (these situations included misjudgments, unpreparedness, proximity to other road users, inappropriate speeds, etc.…) are the main causes in both the VRU groups. Distinctions were found for aspects of car collision speed, accident scenario, distribution of head contact points and so on.

This paper is dedicated to the study and improvement of the aerodynamic properties of the feeder airship in the context of MAAT project. FP7 MAAT project is based on the concept of two different types of airships (the cruiser and the feeder) working together as a transportation system. The current feeder concept includes unconventional shape changing envelope. Two problems are considered in this paper. The first problem is to find a condition of the effective vertical ascent for the feeder (from the ground to the altitude of the cruiser). A series of CFD simulations were carried out for the top flow for a range of altitudes from 0 to 16 km and velocities between 2 and 10 m/s. The results confirm the appearance of some negative effects, including high drag during the vertical ascent, especially, at low altitudes. The second problem is to study and reduce the side wind effects on the ascending feeder airship.

Vehicle traffic accidents have been extensively studied in various countries, but any differences in traffic accidents the studied areas have not yet been adequately investigated. This paper aims to make a comparison study of head injury risks and kinematics of adult pedestrian accidents in Changsha, China, and Hannover, Germany, as well as correlate calculated physical parameters with injuries observed in real-world accidents of the two cities. A total of 20 passenger cars versus adult pedestrian accidents were collected from the two areas of study, including 10 cases from Changsha and 10 cases from Hannover. Virtual accident reconstructions using PC-Crash and MADYMO software were performed. The in-depth study focused on head injury risks while kinematics were conducted using statistical approaches. The results of the analysis of the Chinese data were compared with those of the German data.

Head injury is quite frequently occurred in car-to-pedestrian collisions, which often places an enormous burden to victims and society. To address head protection and understand the head injury mechanisms, in-depth accident investigation and accident reconstructions were conducted. A total of 6 passenger-cars to adult-pedestrian accidents were sampled from the in-depth accident investigation in Changsha China. Accidents were firstly reconstructed by using Multi-bodies (MBS) pedestrian and car models. The head impact conditions such as head impact velocity; position and orientation were calculated from MBS reconstructions, which were then employed to set the initial conditions in the simulation of a head model striking a windshield using Finite Element (FE) head and windshield models. The intracranial pressure and stress distribution of the FE head model were calculated and correlated with the injury outcomes.

Low emission heavy-duty diesel engines are increasingly utilizing four-valve designs with vertical central injectors. However, two-valve DI diesel engines with inclined injectors offset from the centerline of the piston bowl are likely to continue to be used in medium and light duty applications for some time. In such situations, designing of the hole-type nozzle is very difficult and may cause unavoidable back-drilling problems. The purpose of this paper is to solve back-drilling problems connected with hole-type nozzles and improve fuel-air mixing which leads to more efficient combustion. Based on geometric considerations, this paper introduces single-cone hole-type nozzles, double-cone hole-type nozzles, and the critical principal angles for hole-type nozzles. The single-cone hole-type nozzles and double-cone hole-type nozzles can meet requirements for height of the spray impingement points and spray orifice distribution angle at the same time.

This report describes tests of a fuel additive in a medium-duty, high-swirl, direct-injection diesel engine. The additive was found to have little influence on general combustion performance or on NOx emissions. On the other hand, it had a profound effect on particulate emissions. This was most clear under high load where particle emissions are highest. Here, when the engine was switched from running on the base fuel to the additive treated fuel, particle emissions at first increased and then fell to levels about 40% lower (by particle volume) than those initially produced by the base fuel. The additive had a long lasting effect. After running with the additive for about 25 hours, emission levels with the base fuel were only slightly higher than those with the additive treated fuel. We believe that the additive action is associated with a combination of cleaning and surface conditioning. More work should be done to understand the relative importance of these two mechanisms.