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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.

The RON(Research Octane Number) is the most important indicator of motor petrol, and the petrol refining process is one of the important links in petrol production. However, RON is often lost during petrol refining and RON Loss means the value of RON lost during petrol refining. The prediction of the RON loss of petrol during the refining process is helpful to the improvement of petrol refining process and the processing of petrol. The traditional RON prediction method relied on physical and chemical properties, and did not fully consider the high nonlinearity and strong coupling relationship of the petrol refining process. There is a lack of data-driven RON loss models. This paper studies the construction of the RON loss model in the petrol refining process.

Using the nonlinear finite element analysis, three nonlinear characteristics of the rubber gasbag of the air spring on the bus are thoroughly analyzed, including the nonlinear characteristic of the rubber gasbag with multi layers of composite materials, the nonlinear large displacement geometry characteristic of the rubber gasbag on working, and the nonlinear contact characteristic of the rubber gasbag when contacts the pedestal and the top cover plate. A model is build and the nonlinear characteristic of the air spring on the bus is analyzed using the ABAQUS software. At last, the article discusses parameters that influence on the characteristic of the air spring for the bus.

To satisfy the power and energy requirement of the systems, such as electrical vehicles, the battery packs are constructed with hundreds of single cells connected in series and parallel connection. The most significant difference between a single cell and a battery pack is cell-to-cell variation. Not only does cell-to-cell variation have a big effect on the available energy and power of the battery packs, but also it causes early degradation of battery and potential safety issues. The cell variation effects on battery packs are widely studied because it is of great significance for battery sorting and management scheme. In this paper, battery pack inconsistency is clearly defined and the resulting battery capacity loss and aging acceleration problems are analyzed in detail. A comprehensive LiFePO4 battery pack model was established, which has taken into account cell-to-cell variation, thermal model, capacity degradation, resistance increasing and different battery topologies.

Active control of low-frequency engine order noise helps to improve the passenger’s sense of hearing, so it has become one of the hot topics in the automotive field. Depth improvement of active noise control (ANC) performance from the perspective of novel algorithms has attracted the attention of researchers. The conventional notch dual-channel filtered-x least mean square (NDFxLMS) algorithm shows acceptable noise reduction for the elimination of engine order noise. To further enhance the steady-state ANC effect, this paper proposed two new notch algorithms: the notch dual-channel filtered-x recursive least square (NDFxRLS) algorithm and the notch dual-channel affine projection (NDAP) algorithm. Vehicle simulation tests show that both the proposed algorithms, especially the NDFxRLS algorithm, have a satisfying performance for the cancellation of interior noise from the engine.

In contrast to functionality and reliability, which are more and more assumed to be a natural and necessary condition of any vehicle, the performance of Noise, Vibration and Harshness (NVH) now belongs to those features which play an essential role for the customer's purchasing decision. Sound design and vehicle interior noise control are essential parts of NVH. One tool of the NVH solution toolbox is Active Noise Control (ANC). ANC technology aims to cancel unwanted noise by generating an “anti-noise” with equal amplitude and opposite phase. Owing to the fact that human hearing has selective sensitivity for different critical bands, a new control strategy of ANC, which selectively controls the noise of specific bandwidths according to the result of specific loudness and retains the part of noise created by the normal running of facilities, trying to attenuate the unwanted and unacceptable noise, has been proposed in this paper.

Numerical simulations on the fluid-structure interaction were conducted using commercial software STAR-CCM+ and ABAQUS. The aeroelastic responses of a deflector under several different working conditions were simulated utilizing finite volume and finite element methods to investigate the aeroelastic problem of automotive deflectors. Results showed that the structural response of a top deflector is minimal under the influence of aerodynamics given its large structural stiffness. The size of the top deflector was optimised by using thickness as a variable. The volume and quality of the top deflector were significantly reduced, and its lightweight performance was improved to satisfy the stiffness performance requirement. The vibration of a side deflector structure was mainly induced by the turbulence on the structure surface. The amplitude of vibration was small and the vibration gradually converged in a few seconds without obvious regularity.

Failure of high voltage cables (HVCs) which sometimes occurs in electric vehicle collision is one of the fuses that leads to severe thermal runaway of the traction battery system, which has not gotten thorough investigations. This paper presents an experiment and simulation study on the failure behaviors of HVCs under indentation loadings. Tests were performed with different combinations of indenter (cylinder indenter with a diameter of 5 mm which was labeled as D5, cylinder indenter with a diameter of 15 mm which was labeled as D15 and wedge indenter with an angle of 60° which was labeled as V60) and loading speed (1.5 mm/min for quasi-static and 2m/s for dynamic). Experimental results indicated that the failure behavior of HVCs was both influenced by the indenter shape and loading speeds. Sharp indenter will led to a component failure sequence from outmost to innermost.

With the capability of avoiding failure in advance, failure prediction model is important not only to end users, but also to the service engineers in vehicle industry. This paper proposes an approach based on anomaly detection algorithms and telematic data to predict the failure of the engine air system with Turbo charger. Firstly, the relationship between air system and all obtained features are analyzed by both physical mechanism and data-wise. Then, the features including altitude, air temperature, engine output power, and charger pressure are selected as the input of the model, with the sampling interval of 1 minute. Based on the selected features, the healthy state for each vehicle is defined by the model as benchmark. Finally, the ‘Medium surface’ is determined for specific vehicle, which is a hyperplane with the medium points of the healthy state located at, to detect the minor weakness symptom (sub-health state).

The slip ratio of vehicle driving wheels is easily beyond a reasonable range in the complex and changeable driving conditions. In order to achieve the adaptive acceleration slip regulation of four-wheel driving (4WD) vehicle, a fuzzy control strategy of Automatic Drive Train Management (ADM) system based on road situation identification was proposed in this paper. Firstly, the influence on the control strategy of ADM system was analyzed from two aspects, which included the different road adhesion coefficients and the vehicle’s ramp driving state. In the meantime several quantitative expressions of relevant control parameters were derived. Secondly, the fuzzy logic control algorithm was adopted to design a road situation identification subsystem and a ramp driving state identification subsystem respectively. The former was based on the μ-S curve model, and the latter was based on the vehicle driving equilibrium equation.

For the purpose of predicting the interior noise of a passenger automobile at middle and high frequency, an energy finite element analysis (EFEA) model of the automobile was created using EFEA method. The excitations including engine mount excitation and road excitation were measured by road experiment at a speed of 120 km/h. The sound excitation was measured in a semi-anechoic chamber. And the wind excitation was calculated utilizing numeric computation method of computational fluid dynamics (CFD). The sound pressure level (SPL) and energy density contours of the interior acoustic cavity of the automobile were presented at 2000 Hz. Meanwhile, the flexural energy density and flexural velocity of body plates were calculated. The SPL of interior noise was predicted and compared with the corresponding value of experiment.

With the rapid development of intelligent driving technology, there has been a growing interest in the driving comfort of automated vehicles. As vehicles become more automated, the role of the driver shifts from actively engaging in driving tasks to that of a passenger. Consequently, the study of the passenger experience in automated driving vehicles has emerged as a significant research area. In order to examine the impact of automatic driving on passengers' riding experience in vehicle platooning scenarios, this study conducted real vehicle experiments involving six participants. The study assessed the subjective perception scores, eye movement, and electrocardiogram (ECG) signals of passengers seated in the front passenger seat under various vehicle speeds, distances, and driving modes. The results of the statistical analysis indicate that vehicle speed has the most substantial influence on passenger perception.

An identification method using recursive least-squares method with moving data window and reduced-order disturbance observer iteratively is proposed in this paper to identify fast time-varying braking force in the electronic mechanical braking system (EMB). For the type of EMB which generates braking force by balls screw and motor mounted beside wheel, the actuator will go rapidly to eliminate clearance at beginning of braking process by means of raising the braking response speed, and at the same time, increasing the motor output torque which might be far larger than required. The proposed identification method is able to identify the point of contact between the brake pads and the disk in time by identifying the change of break force, and the torque of motor will be changed in time to reduce the braking force overshoot so that brake locking is avoided.

Metal foil is a widely used material in the automobile industry, which not only is the honeycomb barrier material but is also used as current collectors in Li-ion batteries. Plenty of studies proved that the mechanical property of the metal foil is quite different from that of the metal sheet because of the size effect on microscopic scale, as the metal foil shows a larger fracture stress and a lower ductility than the metal sheet. Meanwhile, the fracture behavior and accurate constitutive model of the metal foil with the consideration of the strain rate effect are widely concerned in further studies of battery safety and the honeycomb. This article conducted experiments on 8011H18 aluminum foil, aiming to explore the quasi-static and dynamic tension testing method and the anisotropic mechanical behavior of the very thin foil. Two metal foil dog-bone specimens and three types of notched specimens were tested with a strain rate ranging from 2 × 10−4/s to 40/s and various stress states.

For the purpose of lessening fuel consumption, engine noise, shift jerk and clutch friction work in the shift process of Automatic Mechanical Transmission (AMT), a fuzzy-bang bang dual mode control strategy for engine rotate speed is put forward in this paper, which takes the advantages of time optimal control and fuzzy control. The combined control strategy is applied to the shift process control of AMT test minibus named SC6350 and proved to be successful by the experimental results.

In order to study the static and dynamic characteristics of the thrust rod. Based on the multi-body dynamics theory, the dynamic model of the thrust rod and the vehicle system is established by using ADAMS software. The limit braking condition is simulated, and the limit braking load of the thrust rod is obtained. Thrust rod finite element model is established, the load calculation value and rubber test data as a finite element analysis of input conditions, using ABAQUS software to carry on the stiffness and strength analysis, analysis results show that the strength meets the requirement, and the stiffness and strength calculation result is in good agreement with the sample test, accurately describes the finite element model. The analytical method used can be used to predict the stiffness of the thrust rod.

The automotive industry is aggressively pursuing fuel efficiency improvements through hybridization of production vehicles, and there are an increasing number of racing series adopting similar architectures to maintain relevance with current passenger car trends. Hybrid powertrains offer both performance and fuel economy benefits in a motorsport setting, but they greatly increase control complexity and add additional degrees of freedom to the design optimization process. The increased complexity creates opportunity for performance gains, but simulation based tools are necessary since hybrid powertrain design and control strategies are closely coupled and their optimal interactions are not straightforward to predict. One optimization-related advantage that motorsports applications have over production vehicles is that the power demand of circuit racing has strong repeatability due to the nature of the track and the professional skill-level of the driver.

The lightweight technology takes an important role in electric vehicle(EV) energy conservation domain, as lighter vehicle means less energy consumed under same condition. In this paper, the typical energy requirement in an NEDC cycle is investigated, and the relationship between lightweight rate and energy consumption reduction effectiveness is given. The benefit of lightweight to EV come from the less battery cost because of less energy requirement. For EVs, with less battery cost, a certain lightweight rate can be obtained with less total cost. On the other hand, if lightweight rate is very high, the battery cost won't be able to cover the lightweight cost. Besides, the relationship between driving range and battery capacity is discussed in this paper. It is found that there is a limitation of EV driving range, which is determined by the battery energy density.

The collision accidents of electric vehicles are gradually increasing, and the response of battery cell under mechanical abuse conditions has attracted more and more attention. In the real collision, the mechanical load on battery generally has the following characteristics, including multiple loading directions, dynamic impact and blunt intrusion. Therefore, it is necessary to study the mechanical response and deformation of battery under complex loading, especially in-plane dynamic loading condition. According to the actual accident, we designed the constrained blunt compression test of the battery in different speeds and directions. For out-of-plane loading, the structural stiffness of battery increases obviously and the fracture is advanced compared with the corresponding quasi-static tests. For in-plane constrained loading, the force response can be approximately divided into two linear segments, in which the structural stiffness increases abruptly after the inflection point.

The new control algorithm for parallel hybrid electric vehicle is presented systematically, in which engine operation points are limited within higher efficient area by the control algorithm and the state of charge (SOC) is limited in a range in order to enhance the batteries' charging and discharging efficiency. In order to determine the ideal operating point of the vehicle's engine, the control strategy uses a lookup table to determine the torque output of the engine. The off-line simulation model of parallel HEV power train is developed which includes the control system and controlled objective (such as engine, electric motor, battery pack and so on). The results show that the control algorithm can effectively limite engine and battery operation points and much more fuel economy can be achieved than that of conventional one.