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Urethane is utilized to bond the windshield and backlite to the vehicle frame. The contribution of different modulii of glass bonding urethane adhesives on the stiffness characteristics of the vehicle is studied through finite element analysis. The modal analyses of a finite element body-in-white model with different modulii of urethanes are performed, and the analyses show that high modulus urethane makes notable contribution to the vehicle stiffness. The optimized modulus of urethane adhesive is suggested based on the analyses.

As one of the most challenging driving tasks, parking is a common but particularly troublesome problem in large cities. Recently, an excellent solution-automated valet parking (AVP) has become a hot research topic, which allows the driver to leave the vehicle in a drop-off area, while the vehicle driving into the parking slot by itself. For AVP, the precise localization is an indispensable module. However, the global positioning system (GPS) cannot be used in the underground parking lot and the localization method based on lidar is too expensive. In response to solve this problem, we propose a simultaneous localization and mapping system with the semantic information of parking slots (PS-SLAM), which is based on visual-inertial and around view images. First, the calibration of multi-sensors is conducted to obtain their intrinsic and extrinsic parameters. In this way, the around view image and transformation matrices between sensors can be acquired.

The around view monitor (AVM) system for vehicles usually suffers from the distortion of surrounding objects caused by incomplete rectification and stitching, which seriously affects the driver's judgment of the surrounding environment during the reversing process. In response to solve this problem, an augmented around view monitor (AAVM) system fusing image and depth information is proposed, which highlights the point clouds of persons or vehicles at the rear of the vehicle. First, an around view image is generated from four fisheye cameras. Then, the calibration of multi TOF cameras is conducted to improve their accuracy of depth estimation and obtain extrinsic camera positions. Next, the 2D-driven object point cloud detection method is proposed to localize and segment object point clouds like vehicles or persons.

In this paper, the MDO analysis is applied to the design integration in terms of NVH and crash safety. Considering the difference of characteristics in these two fields, all the design variables are used to construct the response surfaces in the NVH analysis, while for crash safety analysis, these design variables are split into three groups, front, side and rear, to reduce the computational cost. Many of the structure performance indices in the NVH and crash safety fields are included as the constraints in the MDO analysis, which proves that the design integration of these two fields through MDO analysis is feasible. A comparison of crash safety optimization and crash safety-NVH MDO is done through a parallel-coordinate diagram. The difference provides the CAE engineers to find the guidance to modify the original design architecture.

Vehicles that meet the Federal Tier II and the California LEV II Vehicle Standards (e.g. ULEV and SULEV) are a rapidly growing percentage of the fleet. Sales weighted fleet average emissions of new vehicles are already below the LEV certification levels and should be below ULEV certification levels within two years. ULEV and SULEV vehicles represent the “typical” vehicle future for the next decade or two. Data on particulate emissions from these vehicles are currently very limited. In this study, emission tests using the standard Federal Test Procedure (FTP) were conducted on a small in-use vehicle fleet of ULEV and SULEV vehicles to determine their particulate matter mass emission rates, chemical compositions, particle numbers, and particle size distributions. Particulate sampling utilized Teflon filters for mass determination and quartz filters + PUF-XAD cartridges for chemical speciation. Each bag of the test was sampled separately.

Direct debugging of a vertical takeoff and landing (VTOL) fixed-wing aircraft’s control system can easily result in risk and personnel damage. It is effectively to employ simulation and numerical methods to validate control performance. In this paper, the attitude stabilization controller for VTOL fixed-wing aircraft is designed, and the controller performance is verified by MATLAB and visual simulation software, which significantly increases designed efficiency and safety of the controller. In detail, we first develop the VTOL fixed-wing aircraft’s six degrees of freedom kinematics and dynamics models using Simulink module, and the cascade PID control technique is applied to the VTOL aircraft’s attitude stabilization control. Then the visual simulation program records the flight data and displays the flight course and condition, which can validate the designed controller performance effectively.

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.

The hydraulic retarder is the most stabilized auxiliary braking system [1-2] of heavy-duty vehicles. When the hydraulic retarder is working during auxiliary braking, all of the braking energy is transferred into the thermal energy of the transmission medium of the working wheel. Theoretically, the residual heat-sinking capability of the engine could be used to cool down the transmission medium of the hydraulic retarder, in order to ensure the proper functioning of the hydraulic retarder. Never the less, the hydraulic retarder is always placed at the tailing head of the gearbox, far from the engine, long cooling circuits, which increases the risky leakage risk of the transmission medium. What's more, the development trend of heavy load and high speed vehicle directs the significant increase in the thermal load of the hydraulic retarder, which even higher than the engine power.

Anthropometric data are crucial to vehicle ergonomics and safety design. The Chinese population has smaller body size than that of the Western population, while the current crash dummies were developed based on statures of the Western population. To provide effective crash protection for Chinese occupants and pedestrians, Chinese anthropometric data are needed. In the present study, three available Chinese anthropometric databases were surveyed and compared, and it was found that none of them can give reliable and complete anthropometric data. Thus, a mapping method was developed based on correlation and regression analysis to rebuild a reasonable and completed Chinese anthropometric database. Furthermore, the differences between Chinese body size and that of the current dummies were discussed and an example was given to demonstrate the influences of body size on injuries.

The around view monitor (AVM) system for the long-body road vehicle with multiple articulated carriages usually suffers from the incomplete distortion rectification of fisheye cameras and the irregular image stitching area caused by the change of relative position of the cameras on different carriages while the vehicle is in motion. In response to these problems, a set of calibration and stitching methods of AVM are proposed. First, a radial-distortion-based rectification method is adopted and improved. This method establishes two lost functions and solves the model parameters with the two-step optimization method. Then, AVM system calibration is conducted, and the perspective transformation matrix is calculated. After that, a static basic look-up table is generated based on the distortion rectification model and perspective transformation matrix.

The performance of a commercial Cu-zeolite SCR catalyst after differing degrees of hydrothermal aging (aged for 72 hours at 500, 700 and 800°C with 10% moisture balanced with air) was studied by spatially resolving different key reactions using gas-phase FTIR measurements. Gases were sampled along a channel at different positions and analyzed using FTIR, which overcomes the interference of water and nitrogen on ammonia concentration detection encountered in standard mass spectrometer-based spatial resolution measurements. The NO:NO₂ concentration ratio was changed so that the standard (NO:NO₂ = 1:0), fast (NO:NO₂ = 1:1) and NO₂ (NO:NO₂ = 0:1) SCR reactions could be investigated as a function of the catalyst's hydrothermal aging extent. In addition, the effects of hydrothermal aging on the activity of NH₃ and NO oxidation were also investigated. Hydrothermal aging had little effect on NO oxidation activity.

The on-board charger and DC/DC undertake the power conversion function between AC charging of new energy vehicles and low-voltage power supply of the vehicle, which are indispensable parts of the vehicle system. With the rapid development of electric vehicle industry, the current automotive industry has more and more stringent requirements on power system. Lightweight and high power density are more and more important for OEMs. With the increasing popularity of electric vehicles, how to reduce the cost has become one of the most important indicators for OEMs. In the traditional on-board power supply, the on-board charger and DC/DC are mostly combined as independent parts in the vehicle system. In order to meet the integration requirements of OEMs, the on-board charger and DC/DC are even put on a PCB board or only in a shell, so as to achieve the so-called "integration" requirements.

The dynamics of the desulfation of a Ba-containing and a K-containing NOx storage catalyst have been investigated. When both catalysts were desulfated using a temperature ramp in exhaust that simulated gasoline exhaust with a 13:1 A/F, the maximum desulfation rate for the Ba-containing catalyst was seen at 620°C, while the maximum for the K-containing catalyst was at 760°C. This is consistent with the widely known fact that K2SO4 is more stable than BaSO4. The BaSO4 decomposed when either hydrogen or water was in the feed, but not when both were absent. The decomposition, therefore, requires hydrogen to be present and the water can provide sufficient hydrogen for the decomposition via the water-gas shift reaction. With either water or hydrogen in the uncycled feed, the primary sulfur compound formed from the decomposition was H2S for both the Ba and K-containing catalysts.

Light duty gasoline vehicles (LDGV) are estimated to contribute 40% of the total on-road mobile source tailpipe emissions of particulate matter (PM) in California. While considerable efforts have been made to reduce toxic diesel PM emissions going into the future, less emphasis has been placed on PM from LDGVs. The goals of this work were to characterize a small fleet of visibly smoking and high PM emitting LDGVs, to explore the potential PM-reduction benefits of Smog Check and of repairs, and to examine remote sensing devices (RSD) as a potential method for identifying high PM emitters in the in-use fleet. For this study, we recruited a fleet of eight vehicles covering a spectrum of PM emission levels. PM and criteria pollutant emissions were quantified on a dynamometer and CVS dilution tunnel system over the Unified Cycle using standard methods and real time PM instruments.

EuroSID-2 and EuroSID-2re are among the most frequently used side impact dummies in vehicle crash safety. Radioss is one of most widely applied finite element codes for crash safety analysis. To meet the needs of crash safety analysis and to exploit the potential of the Radioss code, a new generation of EuroSID-2 (ES2) and EuroSID-2re (ES2_RE) Radioss dummies was developed at First Technology Safety System (FTSS) in collaboration with Altair. This paper describes in detail the development of the ES2/ES2_RE dummies. Firstly whole dummy meshes were created based on CAD data and intensive efforts were made to obtain penetration/intersection-free models. Secondly FTSS finite element certificate tests at component level were conducted to obtain satisfactory component performances. These tests include the head drop test, the neck pendulum test, the lumbar pendulum test and the thorax drop test [ 1 , 2 ].

In recent years, more attentions have been paid to stringent legislations on fuel consumption and emissions. Turbocharged downsized gasoline direct injection (DI) engines are playing an increasing important role in OEM’s powertrain strategies and engine product portfolio. Dongfeng Motor (DFM) has developed a new 1.0 liter 3-cylinder Turbocharged gasoline DI (TGDI) engine (hereinafter referred to as C10TD) to meet the requirements of China 4th stage fuel consumption regulations and the China 6 emission standards. In this paper, the concept of the C10TD engine is explained to meet the powerful performance (torque 190Nm/1500-4500rpm and power 95kW/5500rpm), excellent part-load BSFC and NVH targets to ensure the drivers could enjoy the powerful output in quiet and comfortable environment without concerns about the fuel cost and pollution.

A novel urea evaporation and mixing device has been developed to improve the overall performance of a urea-SCR system. The device was tested with a MY2007 Cummins ISB 6.7L diesel engine equipped with an SCR aftertreatment system. Test results show that the device effectively improved the overall NO conversion efficiency of the SCR catalyst over both steady-state and transient engine operating conditions, while NH₃ slip from the catalyst decreased.

Exhaust Gas Recirculation (EGR) is an extensively applied approach for the engine emission control, which is the most effective for reducing NOX emissions. However, as increasing EGR rate, the burning velocity of LPG mixture will be slow that it impacts the complete combustion and combustion stability. The effects of EGR on the rapid lean-burning and NOX emissions of the LPG engine with EFI is introduced in this paper. Test data showed that the dual-spark plug ignition-based rapid burning system could increase the combustion rate of LPG mixture, and improve the rapid burning process of the LPG engine with EGR. Meanwhile, the excess air rate Φa limits of LPG lean-burning will be largely extended within the whole effective range of EGR rate. At the equivalent running conditions of LPG engine, largely extended EGR rate could restrain the formation of NOX emissions by the high combustion temperature.

As vehicle fuel economy requirements continue to increase it is becoming more challenging and expensive to simultaneously improve fuel consumption and meet emissions regulations. The Passive Ammonia SCR System (PASS) is a novel aftertreatment concept which has the potential to address NOx emissions with application to both lean SI and stoichiometric SI engines. PASS relies on an underfloor (U/F) SCR for storage of ammonia which is generated by the close-coupled (CC) TWCs. For lean SI engines, it is required to operate with occasional rich pulses in order to generate the ammonia, while for stoichiometric application ammonia is passively generated through the toggling of air/fuel ratio. PASS serves as an efficient and cost-effective enhancement to standard aftertreatment systems. For this study, the PASS concept was demonstrated first using lab reactor results which highlight the oxygen tolerance and temperature requirements of the SCR.

BOBC (Bi-directional on-board charger) is a power conversion system component for AC charging and discharging of new energy vehicles. It has two working modes: AC charging mode and AC discharge mode. In the two working modes, the BOBC belongs to both the controller and the actuator. In some extreme cases such as communication and control failure of the AC charging mode, new energy vehicles have the risk of high-voltage battery overcharging and overheating, which will lead to high-voltage battery fire or even explosion. In the AC discharge mode, it involves the actual operation of the users on electricity, and the risk of short circuit and open circuit may happen in the process, which endangers the safety of the users. Based on the risks brought by the two working modes, it should pay more attention to the safety of the BOBC.