Vehicle Parts Research Articles

Ballistic Performance and Microstructure of Tempered AISI 4130 Steel

Heat treatment methods are generally carried out to increase ductility, increase hardness, increase metal tensile stress, and so on. AISI 4130 steel is commonly used for manufacturing equipment, vehicle parts, stone-crushing machines to body armor. To improve the quality of the steel, heat treatment is required by providing austenitizing and tempering processes. This study aims to determine the hardness, density, and ballistic performance of AISI 4130 steel after tempering at 290oC. The results of experiments on AISI 4130 steel which has been tempered at a temperature of 290oC with a time of 90 minutes. Gets a hardness of 45 HRC. For the density test, the result is 7.85 g/cm3. With the results of the ballistic test getting the numbers V = 635 m/s and V50 = 600 m/s, the penetration mode is plugging.

Trace Metals and Polycyclic Aromatic Hydrocarbons in the Snow Cover of the City of Nizhnevartovsk (Western Siberia, Russia).

The city of Nizhnevartovsk is one of the centers of oil production in Western Siberia (Russia). A survey of the contents of trace metals and metalloids (TMMs) and polycyclic aromatic hydrocarbons (PAHs) in the snow cover was conducted there. It was aimed to study insoluble particles in the snow where the predominant fraction of pollutants in urban areas is concentrated. In contrast to the background area, the deposition of TMMs in Nizhnevartovsk increases by 1-2 orders of magnitude. The deposition of V and Mn increases by 37 and 88 times, respectively, and the deposition of W increases at most (by 98 times). Abrasion of spikes of winter tires, abrasion of metal parts of vehicles, and combustion of motor fuels cause the pollution with W, Co, and V, respectively. The total content of 12 EPA PAHs in the particulate fraction of snow in the urban area averaged 148.2ngl-1, and the deposition rate was 17.0μg/m2. In contrast to the background area, the fraction of high molecular weight 5-6-ring PAHs significantly increases in the city, especially dibenzo(a,h)anthracene (DahA). The indicative ratios of PAHs showed that the snowpack composition was influenced by both petrogenic and pyrogenic sources. The proportion of pyrogenic sources is the highest in the low-rise residential area due to fuel combustion to produce heat and burning of household waste. The impact of motor transport is also major and is manifested in the maximum pollution in areas of heavy traffic. No emissions of PAHs from oil spills from the nearby Samotlor oil field have been identified. It is concluded that the hydrocarbon pollution of the atmosphere from the field weakens during the winter period compared to the warm season. Application of the integral TDF index characterizes the majority (72%) of the studied samples as lowly polluted, 24% of the observation sites are classified as moderately polluted, and one (4%), as highly polluted. The maximum TDF values are observed in the industrial area. The data obtained during the study allowed us to identify the central areas and sites along the roads with the heaviest traffic as the most contaminated areas of the city. This study can be a reference for air pollution monitoring in Nizhnevartovsk.

A Composite Exponential Reaching Law Based SMC with Rotating Sliding Surface Selection Mechanism for Two Level Three Phase VSI in Vehicle to Load Applications

Voltage source inverters (VSIs) are an integral part of electrical vehicles (EVs) to enhance the reliability of the supply power to critical loads in vehicle to load (V2L) applications. The inherent properties of sliding mode control (SMC) makes it one of the best available options to achieve the desired voltage quality under variable load conditions. The intrinsic characteristic of robustness associated with SMC is generally achieved at the cost of unwanted chattering along the sliding surface. To manage this compromise better, optimal selection of sliding surface coefficient is applied with the proposed composite exponential reaching law (C-ERL). The novelty of the proposed C-ERL is associated with the intelligent mix of the exponential, power, and difference functions blended with the rotating sliding surface selection (RSS) technique for three phase two level VSI. Moreover, the proposed reaching law along with the power rate exponential reaching law (PRERL), enhanced exponential reaching law (EERL), and repetitive reaching law (RRL) were implemented on two level three phase VSI under variable load conditions. A comparative analysis strongly advocates the authenticity and effectiveness of the proposed reaching law in achieving a well-regulated output voltage with a high level of robustness, reduced chattering, and low %THD.

Vibration Simulation of the Turbine Rotor System of an Underwater Vehicle Considering the Bearing Radial Clearance

The turbine rotor system (TRS) is one important part of an underwater vehicle (UV). Its vibration and noise characteristics can greatly affect the performance and service life of the UV. To study the influence of radial clearance of supporting bearings on the vibrations of the whole TRS of the UV, a flexible dynamic model of the TRS is established by using the finite element and multi-body methods. Vibrations of the TRS from the rigid and flexible dynamic models under different bearing clearance conditions are analyzed. Note that the TRS with the flexible body model can obtain more accurate vibrations than the rigid one. The maximum vibration amplitude increases with the increment of bearing clearance. The bearing clearance of 5 micrometers to 20 micrometers is more reasonable for controlling the system vibration. The smaller clearance of supporting bearings of the TRS can cause more stable vibration responses. This paper can provide additional guidance for the accurate simulation analysis method of the TRSs of the UVs.

Structural optimization design of a bolster based on a simulation-driven design method

Abstract A simulation-driven design method which uses multiple optimization methods can effectively promote innovative structural design and reduce the product development cycle. Meanwhile, the sub-model technology which has more detailed simulation and optimization analysis can enormously improve the efficiency of modelling and solving. This study establishes a general workflow of structural optimization for a stainless-steel metro bolster by combining the simulation-driven design method and sub-model technology. In the sub-model definition phase, the end underframe sub-model which contains the bolster is obtained based on the whole car body finite element (FE) model, and the effectiveness of the end underframe sub-model is also proved. In the conceptual design phase, the topology path inside the bolster is obtained by the topology method and the optimized structure of the inner ribs inside the bolster is determined according to manufacturing processes and design experiences. In the detailed design phase, the thickness of each part of the bolster is determined by size optimization. The simulation analyses indicate that the requirements of static strength and fatigue strength are fulfilled by the optimized bolster structure. Besides, the weight can be reduced by 11.18% and the weld length can be decreased by 17.79% compared with the original bolster structure, which means that not only the lightweight design goal is achieved, but also the welding quantity and manufacturing difficulty are greatly reduced. The results show the effectiveness of the simulation-driven design method based on the sub-model technology in the structural optimization for key parts of rail transit vehicles.

구조-유체 연성을 고려한 EGR 시스템의 진동 내구성 분석

Vibration tests have been conducted to verify the structural robustness of mounted vehicle parts experiencing road excitations during driving. Given the difficulty with installing water supply devices, a numerical methodology is required to conduct environmental tests of real vehicle parts containing cooling water. In this study, the structural vibrations of an exhaust gas recirculation (EGR) system with cooling water under base excitations were analyzed considering fluid-structure interactions. A numerical model based on the finite element method (FEM) was simulated to predict the structural responses of the EGR system and pressure fluctuations of its cooling water. To describe a dynamic environmental test, the excitation condition was modeled using experimental acceleration signals. The torsional and bending modes of the cooling water receptor were revealed as important factors in determining the fatigue life. The modal frequencies of the EGR system were lowered and their mode shapes were changed owing to the added mass and fluid coupling of the cooling water. Finally, the durability life under road excitations was predicted using time analysis and Miner’s rule, and its numerical results were verified experimentally.

A Fast Prediction of Open-Circuit Voltage and a Capacity Estimation Method of a Lithium-Ion Battery Based on a BP Neural Network

The battery is an important part of pure electric vehicles and hybrid electric vehicles, and its state and parameter estimation has always been a big problem. To determine the available energy stored in a battery, it is necessary to know the current state-of-charge (SOC) and the capacity of the battery. For the determination of the battery SOC and capacity, it is generally estimated according to the Electromotive Force (EMF) of the battery, which is the open-circuit-voltage (OCV) of the battery in a stable state. An off-line battery SOC and capacity estimation method for lithium-ion batteries is proposed in this paper. The BP neural network with a high accuracy is trained in the case of sufficient data with the new neural network intelligent algorithm, and the OCV can be accurately predicted in a short time. The model training requires a large amount of data, so different experiments were designed and carried out. Based on the experimental data, the feasibility of this method is verified. The results show that the neural network model can accurately predict the OCV, and the error of capacity estimation is controlled within 3%. The mentioned method was also carried out in a real vehicle by using its cloud data, and the capacity estimation can be easily realized while limiting inaccuracy to less than 5%.

Intelligent Diagnosis of Bogie Traction Seat Based on PCA-OVO and SVM Optimized by Modified Arithmetic Optimization Algorithm

The bogie traction seat is the main part of urban rail vehicles and its fault status will affect the safe and smooth operation of the vehicles. For the low accuracy of the traditional detection methods, an intelligent fault diagnosis model of the traction seat based on principal component analysis with one versus one (PCA-OVO) and support vector machine (SVM) optimized by modified arithmetic optimization algorithm is proposed. Firstly, for the difficulty of high-frequency data collection under real working conditions, the simulation platform of the bogie of an urban rail vehicle is built, and the vibration signals of the traction seat are collected and processed in different domains, and then the feature extraction and fusion method based on PCA-OVO is used to obtain the sensitive feature set of the traction seat. Finally, the SVM intelligence recognition model is constructed based on the sensitive feature set data, and its parameters are optimally combined and selected by the modified arithmetic optimization algorithm after introducing the cosine factor. The experiments prove the effectiveness of the model. Experimental results show that the model is effective and provides a new model for fault diagnosis of traction seat of urban rail vehicles.

A Liquid Launch Vehicle Safety Assessment Model Based on Semi-Quantitative Interval Belief Rule Base

As the propulsion part of a space launch vehicle and nuclear weapon missile, the health status of the liquid rocket determines whether the space launch vehicle and nuclear weapon missile can function normally. Therefore, it is of great significance to evaluate the health status of the liquid rocket. As the structure of the liquid rocket is becoming increasingly sophisticated, subjective judgment alone can no longer meet the needs of the actual system. As an expert system and a gray-box model, the belief rule base (BRB) can process both qualitative and quantitative information. The expert knowledge base is used in the safety assessment of a liquid rocket. However, in practical applications, the traditional BRB model still has two problems, which are that (1) when there are too many premise attributes, it easily leads to the explosion of combination rules, and (2) the reliability of rules is not considered in the process of model reasoning. Therefore, this paper proposes the BRB model with intervals (intervals-BRB) on the basis of traditional BRB. The interval-BRB retains the advantage of the traditional BRB, which can handle semi-quantitative information. In addition, the proposed model changes the reference point of the prerequisite attribute to the reference interval and changes the rule combination. This solves the problem of the traditional BRB explosive combination rule. The ER-rule (evidential reasoning rule) is introduced into the reasoning procedure, and the weight of the rule and the reliability of the rule are considered at the same time, which solves the shortcoming of the traditional BRB, which does not consider the reliability of the rule in reasoning. Finally, the CMAES optimization algorithm is used to optimize the initial model to obtain better performance. Finally, the model is verified by the actual data set of a liquid rocket, and the experimental results show that the model can achieve good experimental results.

EFFECT OF RETAINED AUSTENITE ON PLASTIC CHARACTERISTICS OF DUAL PHASE STEELS

In terms of the current trend of research and development of new materials and optimization of current materials in the automotive industry, the greatest attention is paid to progressive high-strength dual-phase (DP) steels with increased stampability, which are designed for cold stamping for specific internal car body components of the current market. New grades of DP steels provide a combination of high strength and good formability and contribute to the weight savings of vehicle parts by 10 to 20 %, compared to current DP grades. Thanks to their top properties, DP steels with increased formability can absorb more crash energy using less steel. As a result, high-strength DP780GI and DP780GI-HF materials of first generation (hereinfater DP780GI-HF) were analyzed. The stampability improvement of DP steels was demonstrated by the experimentally determined Forming Limit Curves for both steels.

OPTIMUM DESIGN OF THERMO-PLUNGER SUPPORT IN COMMERCIAL VEHICLES BY USING STRUCTURAL DESIGN AND FINITE ELEMENT METHODS

This paper focuses on creating an optimum design and development of thermo-plunger parts for commercial vehicles in order to save material, reduce mass and make more sustainable automobiles. In this paper, natural frequency analysis, topology, and topography optimization methods have been used to create a new design for the thermo-plunger part. Thermo-plunger means an electric heater that is used for heating the inside of automobiles effectively and quickly and providing customer thermal comfort. It is positioned in the vehicle body, and its support parts have been developed by structural optimization techniques because there is not enough space in the engine compartment for automatic transmission commercial vehicles. The aim of this study is to make a lightweight and reinforced thermo-plunger support part design. Initially, a draft design was created in 3D model software. After that, topology and topography optimizations were applied on this draft design. At the end of studies, a final optimum support design has been obtained. The final design is 41.1% lighter than the initial design. At the same time, above 50 Hz natural frequency value has been obtained on the final design to avoid resonance problems.

Analytical modeling of cross-ply cylindrical composite submersible shell with elastic buckling using first order shear deformation theory

The main objective of this study is to design composite shells i.e. long, short, thin and thick for the different underwater applications. These shells can be a part of pressure hulls, underwater vehicles, pressurized tanks, underwater cables and underwater pipelines etc. This paper presents comprehensive procedures for the mathematical modeling of elastic buckling for submersible composite shells under hydrostatic pressure. First order shear deformation theory (FOSDT) was used for modeling. FOSDT theory was mathematically derived under hydrostatic pressure for composite shells, and it can be used for all types of submersible shells. After the derivation of the theory, mathematical code was formed on MATLAB for this modeling. From the given formulation one can design the shell structure according to his needs on different environment conditions. Different types of composite shells, including moderately thick, thick, long, and short, are investigated for the FOSDT formulation to check the accuracy range. The results were compared with previous studies and finite element analysis FEA. Three types of materials, Carbon/Epoxy, Glass/Epoxy, and Boron/Epoxy, were used with different cross-ply symmetric and unsymmetrical angle configurations. The layups used for the analysis were [0/90/0]s [90/0/90/0]s [02/902]s [90/02/90]s [0/902/0]s [0/0/0/90]s [90/90/90/0]s and [0/90].

Weakly-Supervised Part-Attention and Mentored Networks for Vehicle Re-Identification

Vehicle re-identification (Re-ID) aims to retrieve images with the same vehicle ID across different cameras. Current part-level feature learning methods typically detect vehicle parts via uniform division, outside tools, or attention modeling. However, such part features often require expensive additional annotations and cause sub-optimal performance in case of unreliable part mask predictions. In this paper, we propose a weakly-supervised Part-Attention Network (PANet) and Part-Mentored Network (PMNet) for Vehicle Re-ID. Firstly, PANet localizes vehicle parts via part-relevant channel recalibration and cluster-based mask generation without vehicle part supervisory information. Secondly, PMNet leverages teacher-student guided learning to distill vehicle part-specific features from PANet and performs multi-scale global-part feature extraction. During inference, PMNet can adaptively extract discriminative part features without part localization by PANet, preventing unstable part mask predictions. We address this Re-ID issue as a multi-task problem and adopt Homoscedastic Uncertainty to learn the optimal weighing of ID losses. Experiments are conducted on two public benchmarks, showing that our approach outperforms recent methods, which require no extra annotations by an average increase of 3.0% in CMC@5 on VehicleID and over 1.4% in mAP on VeRi776. Moreover, our method can extend to the occluded vehicle Re-ID task and exhibits good generalization ability.

A contribution to investigation of oscillatory loads of driving axles in order to create conditions for laboratory tests of trucks

Motor vehicles are complex dynamic systems due to spatial vibratory displacements during movement, changes in the characteristics of components during life cycle, a large number of influences and disturbances, the occurrence of clearance, friction, hysteresis, etc. The mentioned dynamic phenomena, especially vibrations, cause fatigue of the driver and passengers, reduce the life cycle of the vehicle and its systems, etc. In the general case, the movement of motor vehicles is done on uneven roads (terrain) and curvilinear paths in flat roads (terrains). Oscillatory movements cause loading of vehicle parts, but they also negatively affect human health. Therefore, even in the design phase of the vehicle, special attention must be paid to the harmonization of the mutual movement of the vehicle subsystem, and in particular, the suspension system. Theoretical, experimental or combined methods can be used for this purpose, and it is very useful to have experimental results of vibration of the vehicle subsystems in real operational conditions. Therefore, it is very useful to have experimental results of vibration of vehicle subsystems in operational conditions. Bearing that in mind, the aim of this wpaper was to use the movement of FAP 1118, 4x4 wheel formula, in operational conditions (due to higher speeds - in road conditions) to define laboratory conditions for testing. This is made possible by registering and identifying statistical parameters of registered quantities.

Uniaxial Load Specification for Vehicle Knuckle Part Using Maximum Stress Similarity in Triaxial Load Case

Knuckle parts have a complex relationship with adjacent vehicle parts, making it difficult to determine the proper fatigue evaluation specification when considering vehicle operation. An accelerated triaxial load case for the knuckle part was derived using a combination of four event modules from the test code developed by the Korea Automotive Technology Institute. The fatigue damage analysis of the front and rear knuckle models was conducted with respect to the accelerated triaxial load case, and the maximum stress was measured at hotspots for the magnitude and orientation of the critical plane. The sensitivity analysis of the knuckle models was conducted for six directions of the unit force, and the proper uniaxial force orientations of the two knuckle models were determined for the maximum stress similarity in the triaxial load case in terms of the magnitude and orientation of the critical plane. The final uniaxial load specification was derived by adjusting the magnitude of the candidate uniaxial load and the error analysis showed reliable results through inverse safety factors with 0.02, 0.04 error, and critical plane angles with 10.8, 0.8 degrees error for front and rear knuckles, respectively, verified by comparing the maximum stress similarity between the triaxial and uniaxial load cases.

A multi-criteria approach to investigate spatial distribution, sources, and the potential toxicological effect of polycyclic aromatic hydrocarbons (PAHs) in sediments of urban retention tanks

Bottom sediments deposited in retention tanks (RTs) located on two urban streams (Oliwski and Strzyza) in the central part of Gdansk (Poland) were analysed for polycyclic aromatic hydrocarbons’ (PAHs) content. PAHs were extracted from samples with methylene chloride, then the extracts were subjected to clean-up applying the solid phase extraction (SPE) method. Quantitative and qualitative determination of 16 PAHs was performed with the use of gas chromatography/mass spectrometry technique. A multi-dimensional approach was applied to analyse PAHs’ spatial distribution, source, and contamination status. Potential sources of PAHs were verified using isomer ratios supported by a statistical approach. The Σ16PAHs (in mg/kg d.w.) ranged from 1.95 ± 0.64 to 20.4 ± 6.8 for RTs located on the Oliwski Stream and from 0.50 ± 0.17 to 8.6 ± 2.9 for RTs located on the Strzyza Stream. PAHs detected in bottom sediments were mainly composed of 4- and 5-ring compounds. PAH isomer ratios such as Phen/Anth, Flth/Pyr, B(a)A/B(a)A + Chry, Inpy/Inpy + B(ghi)P, Flth/Flth + Pyr, Anth/Anth + Phen, and Flth/Flth + Pyr suggested delivery pathways for biomass, coal, and petroleum combustion. Petrogenic PAHs related to fuel leaks from cars were not detected. Statistical analyses confirmed traffic and heating system sources, while factor analysis (FA) pointed out the abrasion of wasting parts of vehicles. Based on threshold levels presented in sediment quality guidelines (SQGs), in most cases, PAHs were at low levels with occasional negative biological effects on organisms. Only sediments deposited in two RTs located on the Oliwski Stream presented harmful features for sediment-dwelling organisms. The risk assessment performed accordingly to the Σ16PAHs presented a moderate and high risk for biota. This study not only reflects the direct threat related to PAH content in bottom sediments, but also highlights the overall pollution of an area, considered to be a recreational part of the city (Oliwski Stream catchment). The findings of this study highlight the need to launch preventative methods to protect the area against pollution from heating system emission and traffic.

Modeling and Simulation of Unmanned Driving System for Load Haul Dump Vehicles in Underground Mines

This paper proposes the modeling and simulation of the unmanned driving system for underground load haul dump vehicles based on Gazebo/Ros. Firstly, the kinematics model of the load haul dump vehicle is derived. Then, the model of each part of the load haul dump vehicle is established based on SolidWorks and the model of the load haul dump vehicle is established by connecting the parts through a unified robot description format (URDF) file. Finally, the laneway model is established by using alpha shape to realize the modeling of the operating environment of the load haul dump vehicle. The speed, angular speed, bucket lifting, and bucket flipping of the load haul dump vehicle are controlled using PID. The experimental results show that: The control errors of the speed and angular speed of the load haul dump vehicle are 0.283 m/s and 0.010 rad/s, respectively. The control error of the lifting bucket is 0.025 m and that of the flipping bucket is 0.015 m. The angular velocity control error of the simulation system relative to the actual system is 0.330 and 0.106 m/s, respectively. The error between the SLAM of the simulation system and the actual system and the measured value is 0.917 and 3.44 m, respectively. The control performance of the load haul dump vehicle in the simulation system is good. Therefore, automatic driving algorithms can be studied and tested in this simulation platform.

The Number of Fall of Separable Parts of Launch Vehicles and the Prevalence of Diseases Among Residents of the Territories of the Altai Territory Adjacent to the Areas of the Fall

Part of the territory of the Altai Region is used as fall areas for separating parts of launch vehicles launched from the Baikonur Cosmodrome. The areas of the fall, adjacent territories and the population of adjacent territories are negatively affected as a result of rocket and space activities. The aim of the study is to identify a possible correlation between the prevalence of certain diseases among residents of the Altai Region living in the area of rocket and space activities and the number of falls of separable parts of launch vehicles. For most of the classes of diseases, a direct strong and medium correlation was revealed. The results were obtained based on the results of a survey of residents of the Charyshsky district of the Altai Region in 1999, 2006, 2011 and 2015.

Measurement of a Vibration on a Robotic Vehicle.

This article deals with the design and construction of a robotic vehicle. The first part of the paper focuses on the selection of suitable variants for the robotic vehicle arrangement, i.e., frame, electric motors with gearboxes, wheels, steering and accumulators. Based on the selection of individual components, the robotic vehicle was built. An important part of the robotic vehicle was the design of the suspension of the front wheels. The resulting shape of the springs was experimentally developed from several design variants and subsequently produced by an additive manufacturing process. The last part of article is devoted to the experimental measurement of the acceleration transfer to the upper part of the frame during the passage of the robotic vehicle over differently arranged obstacles. Experimental measurements measured the accelerations that are transferred to the top of the robotic vehicle frame when the front wheels of the vehicle cross over the obstacle (obstacles). The maximum acceleration values are 0.0588 m/s2 in the x-axis, 0.0149 m/s2 in the y-axis and 0.5755 m/s2 in the z-axis. This experimental solution verifies the stiffness of the designed frame and the damping effect of the selected material of the designed springs on the front wheels of the robotic vehicle.

Aquatic environmental fates and risks of benzotriazoles, benzothiazoles, and p-phenylenediamines in a catchment providing water to a megacity of China

Wearing of vehicle parts could release many chemical additives into the environment, such as benzotriazoles (BTRs), benzothiazoles (BTHs), and p-phenylenediamines (PPDs), which are potentially toxic to wildlife and humans. This study investigated the occurrence, source, and risks of BTRs, BTHs, and PPDs in a source catchment providing water to Guangzhou, a megacity in South China, covering groundwater, surface water, and stormwater. The results showed that BTRs and BTHs were predominant in surface water and groundwater. Unexpectedly, the BTR and BTH concentrations were lower in surface water than groundwater in a third of the paired samples. For the first time, 6PPD-quinone, a toxic ozonation product of N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6PPD), was extensively detected in source waters. Stormwater decreased the BTR concentrations but increased the 6PPD-quinone concentrations in surface water owing to their affiliation to suspended particles. From natural to urban segments of Liuxi river, a downstream increasing trend in BTR and BTH concentrations was observed, confirming that they are indicative of urban anthropogenic activities. Strong correlations between industrial activities and BTR or BTH concentrations in surface water indicated that industrial activities were their main sources. Six compounds were prioritized as potentially persistent, mobile, and toxic (PMT) chemicals, combing our monitoring results and REACH criterion. This study improves our understanding of the environmental fates and risks of water-soluble tire-wear chemicals, which provides important information for chemical management, and indicates attention should be paid to the risk posed by 6PPD-quinone in the source water.