Chassis Components Research Articles

Validation of a new road and contact model for vehicle–soft soil terrain interaction through an elaborate modelling of the FED-Alpha vehicle

Employing multibody dynamic simulations with semi-empirical tyre models is widely recognised as a cost-effective approach. A recent development introduces a novel road and tyre–soil contact model that is not only swift and memory-efficient but also addresses limitations in classical semi-empirical models. This study conducts a thorough validation of the new road and contact model by creating a detailed multibody model of the four-wheeled vehicle, Fuel Efficiency Demonstrator – Alpha, integral to NATO’s Next-Generation reference mobility model. The comprehensive model encompasses the chassis, suspension, tyres, engine, transmission and various other components. Through simulations of various driving scenarios, accounting for complex terrain geometries, spatially varying soil properties and multi-pass phenomena, the model’s performance is evaluated. The simulation results are compared with physical measurements, providing a detailed assessment of the tyre–soil model’s predictive accuracy for wheeled vehicle mobility on deformable terrains.

Frequency–Time Domain Analysis Based on Electrochemical Noise of Dual-Phase (DP) and Ferrite–Bainite (FB) Steels in Chloride Solutions for Automotive Applications

The automotive industry uses high-strength (HS), low-alloy (HSLA) steels and advanced high-strength steels (AHSSs) to manufacture front and rear rails and safety posts, as well as the car body, suspension, and chassis components of cars. These steels can be exposed to corrosive environments, such as in countries where de-icing salts are used. This research aims to characterize the corrosion behavior of AHSSs based on electrochemical noise (EN) [dual-phase (DP) and ferrite–bainite (FB)]. At room temperature, the steels were immersed in NaCl, CaCl2, and MgCl2 solutions and were studied by frequency–time domain analysis using wavelet decomposition, Hilbert–Huang analysis, and recurrence plots (RPs) related to the corrosion process and noise impedance (Zn). Optical microscopy (OM) was used to observe the microstructure of the tested samples. The results generally indicated that the main corrosion process is related to uniform corrosion. The corrosion behavior of AHSSs exposed to a NaCl solution could be related to the morphology of the phase constituents that are exposed to solutions with chlorides. The Zn results showed that DP780 presented a higher corrosion resistance with 918 Ω·cm2; meanwhile, FB780 presented 409 Ω·cm2 when exposed to NaCl. Also, the corrosion mechanism of materials begins with a localized corrosion process spreading to all the surfaces, generating a uniform corrosion process after some exposition time.

Construction of Fatigue Criteria Through Positive‐Unlabeled Learning

AbstractThe reliability of vehicles is a significant issue for automotive manufacturers, with mechanical fatigue representing a pivotal aspect of the design process. To accelerate the development of novel mechanical components, automotive manufacturers are increasingly employing numerical simulations with the objective of markedly reducing the number of prototype validation tests. This requires the utilization of efficient fatigue criteria capable of accurately identifying critical zones in numerical models. However, the current fatigue criteria frequently fail to demonstrate a satisfactory correlation with the results obtained from fatigue test rigs. In response, this paper proposes a probabilistic Dang Van criterion that accounts for variability in fatigue results within a multiaxial context. Additionally, a fatigue database comprising numerical results and test reports on automotive chassis components is introduced. A novel approach utilizing positive‐unlabeled learning is developed to enhance the predictive accuracy of the fatigue criterion. Its effectiveness is demonstrated through application to the fatigue database.

Design and research on structure of plateau hand-held cutting and sun drying machine

With the development of agricultural modernization, accelerating agricultural mechanization has become an important direction for the development of agriculture in China. However, agricultural mechanization is uneven and insufficient in terms of regions, industries, crop varieties, and production stages. Although there are already a large number of agricultural machinery products on the market, most of them are designed for large-scale crops in northern arid lands, lacking machinery suitable for barley and adaptable to small plots and sloping farmlands in the Qinghai-Tibet Plateau region. The development of a barley harvester adapted to plateau mountainous areas contributes to the development of special agricultural machinery in China, improves the uneven development of agricultural mechanization, and promotes agricultural development in plateau mountainous areas. This paper conducts research on the actual terrain of the Qinghai-Tibet Plateau, barley planting conditions, and harvester operational conditions. Based on the production needs of barley agriculture, the design is optimized and improved. Following the principle of overall coordination, the overall structural parameters of the harvester suitable for the operational requirements of plateau mountainous areas are determined. The structural design of key components such as wheelbase, axle spacing, ground clearance, harvesting mechanical arm, and harvesting mechanism is detailed. Additionally, SolidWorks software is used for three-dimensional modeling of the barley harvester. CAE technology is employed to analyze the static and dynamic performance of critical chassis components, validate theoretical calculations, and confirm final structural parameters. Furthermore, a dynamics characteristic model is established based on the optimized parameters to theoretically analyze the stability of the entire machine and verify whether the designed plateau barley harvester meets field operation requirements. Finally, Bluetooth communication technology is utilized to autonomously design control hardware and software, achieving intelligent control of the machinery.

Enhancing GFRP fatigue durability for chassis component applications through glass fiber coupling variation

As the landscape of mobility trends continues to evolve, concerted efforts have been made to incorporate Carbon Fiber Reinforced Plastic (CFRP) into automotive components. However, the substantial increase in cost relative to the achieved weight reduction has limited its widespread adoption. Consequently, research endeavors have focused on exploring alternative composite materials, adapting fibers such as glass fibers, natural fibers, and recycled fibers, to reduce the cost of composite components. Of particular interest in the automotive industry is the utilization of Glass Fiber Reinforced Plastic (GFRP) in chassis components like leaf springs. Nevertheless, the development of GFRP leaf springs encounters a significant challenge related to the adhesive strength at the interface between epoxy resin and glass fibers, which is crucial for enhancing fatigue durability. While glass fibers were traditionally paired with unsaturated polyester or vinyl ester matrices, the pursuit of improved durability has led to the adoption of epoxy matrices. Regrettably, this transition has not consistently yielded the expected gains in interfacial adhesion.In light of these challenges, this study systematically compares the interfacial adhesion strength and fatigue endurance performance. For comparison, two coupling agents widely used commercially, amino silane and epoxy silane, were selected. Glass fibers treated with each coupling agent were purchased commercially, and glass fiber-reinforced plastic (GFRP) specimens were fabricated using the HP-RTM (High-Pressure Resin Transfer Molding) method. Static property evaluations and fatigue durability assessments were conducted using the fabricated specimens. The results showed that when epoxy silane was used as the coupling agent, the interlaminar shear strength (ILSS) increased by approximately 7 %. Furthermore, SEM(Scanning Electron Microscopes) analysis confirmed a significant enhancement in interfacial adhesion, providing support for the ILSS evaluation results. Consequently, the fatigue durability performance improved by approximately six-fold. This confirms that the improvement in interfacial adhesion due to the change in coupling agents led to enhanced fatigue durability performance.

High cycle fatigue life estimation of punched and trimmed specimens considering residual stresses and surface roughness

Shear cutting processes have a detrimental effect on fatigue of high strength metal components. The effect tends to increase with material grade, counteracting the task of reducing weight in chassis components using higher strength materials. Base material fatigue data are often available, but assessment of components with cut edges often require additional costly and time-consuming testing. This paper provides a methodology for estimation of fatigue life reduction by using residual stresses obtained from process simulations, and measured surface roughness in the cut edge. A stress relaxation criterion is applied to handle reduction of the initial local residual stresses. Two complex phase steels and one aluminum alloy are studied for validating the approach. Polished fatigue data is reduced to estimate S–N curves of trimmed and punched specimens at different load ratios. Good agreement between the model and test results are found for all cases. The needed data for the predictions are only a high cycle S–N relationship for polished material, uniaxial tensile properties, and the cut edge fracture surface residual stress and roughness without any parameter fitting, making it a convenient tool for estimating the reduction in fatigue life and for parameter studies.

Syensqo expands its bio-based portfolio with a new MTM® epoxy prepreg

On February 27, 2024, Syensqo, previously part of Solvay Group, announced it had developed a new version of its flagship MTM® 49-3 resin that contains 30% bio-sourced monomers. The new product variant complements the portfolio of the company's MTM® advanced prepregs and targets structural automotive applications, including body panels, chassis components and spoilers.

Methodical Design of a Subframe for a Novel Modular Chassis Concept without Knowledge of Final Vehicle Parameters

<div>This article presents the methodical development of a subframe for a novel on-the-road-modular vehicle concept, which was developed for the U-Shift project. The subframe serves as the basis for a modular chassis. This chassis offers the possibility to exchange chassis components by the operator, which means after completion by the manufacturer, and thus to adapt the vehicle to different purposes. According to the applied methodology, the relevant wheel loads are determined and a geometric reference model is created. By defining the relevant load cases, the forces acting on the subframe, and thus the physical boundary conditions, can be determined from the wheel loads. In addition to the wheel loads and the geometric boundary conditions, no other vehicle parameters are required for the development of the subframe. The results of the topology optimization are used to identify areas of the geometric reference model that are not exposed to high loads. Based on the results of the topology optimization, a suitable combination of manufacturing processes and suitable materials can also be determined. After the basic topology has been determined, a welded construction is derived from square tubes and plates. Subsequently, excess stresses at critical points are identified in simulation and analysis processes, and constructive changes are made to reduce them. Through validation by simulation of the relevant load cases, a proof of compliance with the physical boundary conditions can be provided. The actually manufactured subframe is presented, and the potential of the modular construction for the development of a chassis modular kit is explained.</div>

Tire Performance and Testing under Longitudinal and Combined Slip States: Induced vs Resultant Wheel-Related Slip

ABSTRACT Tires influence many overall vehicle characteristics, including safety, performance, comfort, and handling. Testing is needed to characterize tires for the selection of original equipment manufacturers submissions as well as for the development of other suspension and chassis components. The reality that tire responses are highly nonlinear and change significantly with temperature, wear, and surface pairing makes testing to adequately characterize tires for vehicle development difficult. Furthermore, achieving robust, repeatable braking and driving measurements is particularly challenging. Unlike cornering tests, the test rig input is directly opposed to the tire response vector. Moreover, using an estimated parameter (e.g., slip ratio) as a control value prohibits a clear distinction between the linear test rig input and the nonlinear tire response. In this paper, the influence of the wheel-related slip control on tire performance under longitudinal and combined slip conditions is investigated. Two different tire types are measured in a laboratory environment on an MTS Flat-Trac CT+ tire test rig. A variety of test procedures are used to consider the influence of slip and torque rates under different operating conditions (e.g., wheel loads). A recommendation is given for a low-wear and cost-efficient testing methodology for an improved assessment of tire longitudinal and combined slip characteristics by using a linear test rig input.

AKULTURASI KOMPETENSI BIDANG CHASIS KENDARAAN PADA KURIKULUM BERBASIS KERJASAMA INDUSTRI

AbstractThe potential for human resource development in Chassis' area of expertise is still very broad. In addition, the time span of its usefulness is still very long because it is not displaced by the transition of electric vehicles. Therefore, it is important to conduct research that develops the competence of the Chassis area of expertise, which then cultures it into the curriculum and learning of automotive workshops and partner industries. This type of research is qualitative descriptive research. Data were collected through surveys, interviews, FGDs and observations in the automotive industry regarding wheel alignment competencies. The results showed that attitudes that can be observed and experienced developments when carrying out jobs in campus workshops and the chassis industry include accuracy in measuring chassis components, dexterity in carrying out the sequence of work and responsibility in working on vehicle maintenance and repair needs. In the aspect of automotive technology knowledge, components that can be observed for development includebasic knowledge, working principles, procedures, understanding of construction, knowledge of vehicle safety and security equipment requirements. Meanwhile, the ability to diagnose tire/wheel problems/damage skills according to manual repair procedures and skills in carrying out vehicle chassis maintenance procedures..

Design of Unmanned Landmine Detection Vehicle Using Arduino

The concept presented in this article revolves around the idea of an economically designed UGV (Unmanned Ground Vehicle) for the demining process. Landmine discovery is a critical area of exploration due to the high number of losses and injuries caused by landmines each time. The developed technology generally requires human assistance nearby for landmine detection. Every so often the military bear loss of their equipment specialists. Also, false detection leads to the wastage of resources invested in the technology. Our prime aim is to develop a sturdy design for UGV which require minimum assembly time i.e., “Ready-to-Assemble” concept. This paper outlines the design of a UGV equipped with IR sensor, and metal detector and controlled using Arduino microcontroller. The Arduino microcontrollers are programmed to control the UGV’s movements and the sensor data processing. The UGV is built on a six-wheel drive controlled by two motor drivers, which is equipped with IR sensor to detect the heat signature of buried landmines and a metal detector to detect metallic landmines. The GPS location of the landmine is sent directly to a mobile device using a GSM Module. The UGV is controlled using Bluetooth remotely. The design of the vehicle was performed on Solidworks, CAD software. The software was used to design the chassis, suspension system, and other components such as the metal detector and IR sensor mounts. Proteus software was used to stimulate the electronic circuitry. The UGV has potential applications in detecting and removing landmines safely, minimizing the risk of human casualties. Future work could involve improving the system's accuracy and efficiency to make it a more effective tool for landmine detection and removal.

Design of Intelligent AGV Transport Car

Unmanned Guided Vehicle (AGV) is a new type of mobile robot that was applied in various fields. Aiming at the design of dedicated AGV transport vehicle for complex road conditions, this AGV transport vehicle is composed of chassis, traveling mechanism, lifting device, and removable components. By designing and analyzing the mechanical structure of the AGV transport vehicle, and it’s combined with statics theory, and the feasibility of the trolley structure is designed and discussed. The three-dimensional model of AGV transport vehicle is established by Solid Works software, and the cloud diagram of the stress and deformation of the wheel system structure is analyzed by Solid Works Smillation, and the traveling mechanism of the trolley is analyzed by statics. The rationality of the wheel system structure is verified by the deformation cloud diagram of the AGV transport vehicle under various working conditions. Based on the mathematical model optimization of variable density method, the car body frame is optimized and designed to these materials of car body. The design of the track tensioning structure and frame is obtained according to the four general engineering parameters of TRIZ theory. Finally, the modeling design of intelligent AGV transportation car is carried out by using the principles such as division, color change, and dimension change, etc. In order to facilitate the take-off and landing loading and unloading of goods for AGV transportation lifting device, and it is changed to the traditional handling mode of manpower-operated machines.

Hair surface interactions against different chemical functional groups as a function of environment and hair condition.

The nature and magnitude of molecular interactions on hair surfaces underpin the design of formulated products, of which the application involves a competitive adsorption process between cationic surfactants, fatty alcohols and surface actives such as silicone. The knowledge of molecular interaction with hair surface will not only provide insight on the surface binding affinity but also offer an effective methodology in characterizing surface deposits. Untreated and chemically treated hair samples were treated with either conditioner chassis alone (gel network) or conditioner chassis plus silicone (chassis/TAS). Hair surface interactions against four different chemical functional groups, namely methyl (-CH3 ), acid (-COOH), amine (-NH2 ) and hydroxyl (-OH), were quantified in both ambient and aqueous environment using Chemical Force Microscopy, a method based on atomic force microscopy (AFM). Surface adhesion on hair in ambient is dominated by capillary force that is determined by both the wettability of hair fibre (hydrophobic vs. hydrophilic), presence of any deposits and the chemical functionality of the AFM cantilever. Capillary force is diminished and replaced by electrostatic interaction when polar groups are present on both hair and AFM cantilever. A distinctively different force, hydrophobic interaction, plays a major role when virgin hair and hydrophobic functionalized AFM cantilever make contact in water. Results acquired by AFM cantilevers of different functional groups show that hydrophobic interaction is a key driver for deposition on virgin hair, whilst electrostatic interaction is the most important one for bleached hair. Interfacial conformation of chassis components upon deposition is determined by the hair surface properties. Our study highlights the possibility of a range of polar groups, not necessarily negatively charged, on the damaged hair. Unlike conventional surface chemical analysis method, it is possible to quantitatively evaluate the interfacial conformation of deposited surface actives on hair, which identifies the target moieties for conditioning products on different types of hair.

Application of tailored fiber placement to fabricate automotive composite components with complex geometries

Fabrication of continuous carbon fiber composite components with complex geometries has traditionally been a challenge, yet automotive components are rarely simple in design or loading. Unidirectional and woven fabrics dominate the industry but are limited to generally homogenous microstructure across a layer. Tailored fiber placement (TFP) is a relatively new composite preforming technology that provides a means to address this limitation. In TFP, tows of fibers are positioned by a robotic gantry and stitched in place. This process affords unmatched control over the local fiber orientation. In this study, we design, fabricate, and test a simplified carbon fiber composite connecting rod for an internal combustion engine. Design is aided by performance simulation using the finite element BSAM program. The connecting rods are tested in monotonic compression, monotonic tension, and fatigue. Results show that the TFP process is able to successfully fabricate a high strength carbon fiber composite component featuring a complex structure. Discussion focuses on evaluating achieved performance relative to design targets, correlation between simulated predictions and test results, and evaluation of failure modes from post-failure analysis. The TFP process could be useful to many automotive applications, including seat frames, chassis components, and electric propulsion system components.

Greenhouse Tomato Picking Robot Chassis

In this paper, a greenhouse tomato picking robot chassis that meets the path cruising and setpoint positioning requirements of robots engaged in greenhouse tomato picking operations in China is designed. Based on the trellis-cultivation growing environment of tomatoes, the basic parameters of the chassis and operating space are analyzed to determine the chassis requirements during picking operations. According to these requirements, a kinematic model of a robot chassis with front-wheel steering and rear-wheel driving is constructed, and the planar positioning principle of the chassis is introduced. SOLIDWORKS is used to simulate and design three-dimensional models of the chassis parts, and the ANSYS WORKBENCH plug-in is used to simulate and analyze the bearing performance of key chassis components. ADAMS is used to simulate and evaluate the motion trajectory of the chassis, and the reasonableness of parameters such as the chassis size, selected materials, and load-bearing performance are verified. Based on the simulation results, a physical system is constructed to experimentally verify the straight-line motion and steering performance of the chassis. The experimental results show that the chassis has good cruising and positioning accuracy and meets the specific requirements of path cruising and setpoint positioning in greenhouse tomato picking operations.

Vehicle interior road noise predicted using support vector regression

In this paper, the prediction method of low-frequency vehicle road noise is studied, and the mapping relationship between vehicle road noise and vehicle structural dynamic parameters is discussed. Firstly, through the study of the road noise generation mechanism and NVH (Noise, Vibration and Harshness) target decomposition method, the main influencing factors of vehicle interior road noise and their interaction relationship determined. On this basis, the road noise hierarchical decomposition framework is constructed. Then, combining with 27 data samples which were collected via the road test and design of experiment (DOE), the road noise prediction model is developed through the support vector regression (SVR). In addition, the quantitative mapping relationship between the steering knuckle excitation, chassis component parameters, suspension structure vibration response and vehicle road noise are established as well. Finally, the developed prediction model is verified by 11 samples from the testing set. The test results show that the road noise prediction model based on the SVR algorithm has good prediction accuracy and reliability performance.

Investigation of fatigue strength of root of lap fillet welds of thin sheet and improvement method

This study investigates the dominant factors of fatigue strength at the root of thin-sheet lap fillet arc welds, which are frequently used in automobile chassis components. A method to improve the root fatigue strength was investigated. The direction of fatigue crack propagation at the root coincided with the direction of maximum circumferential stress range. The circumferential stress was reduced by increasing the distance from the toe to the root (penetration width). Fatigue strength originating from the root was improved in welded joints where the penetration width was increased by adjusting the welding aim point and heat input.

Gaussian Processes for Transfer Path Analysis Applied on Vehicle Body Vibration Problems

<div class="section abstract"><div class="htmlview paragraph">Transfer path analyses of vehicle bodies are widely considered as an important tool in the noise, vibration and harshness design process, as they enable the identification of the dominating transfer paths in vibration problems. It is highly beneficial to model uncertain parameters in early development stages in order to account for possible variations on the final component design. Therefore, parameter studies are conducted in order to account for the sensitivities of the transfer paths with respect to the varying input parameters of the chassis components. To date, these studies are mainly conducted by performing sampling-based finite element simulations. In the scope of a sensitivity analysis or parameter studies, however, a large amount of large-scale finite element simulations is required, which leads to extremely high computational costs and time expenses. This contribution presents a method to drastically reduce the computational burden of typical sampling-based simulations. For this purpose, Gaussian processes are introduced to find a probabilistic function approximation of the transfer paths. Initial results reveal that a wider solution space can be explored by only observing a few transfer path samples. This entails a time-efficient and robust technique, which inherently incorporates the variability of the input parameters. As such, Gaussian processes offer a versatile solution strategy for transfer path analyses, where simulation data as well as experimental measurements can be holistically investigated.</div></div>

Conversion of a Lada 2106 car into a rally racing car

The subject of this publication is a rally car designed as a diploma thesis and later produced. G-Sport Ltd. designs and manufactures racing car bodies, chassis components and all other motorsport related components for both the domestic and international markets. The aim was to design the Lada 2106 race car to accept a Ford Mk2 suspension, a Toyota 4A-GE engine and other parts that would enable it to compete in official FIA rally events. The work was done using a 3D scanner. The first phase involved creating 3D models of the body, engine, gearbox and other components, while checking their dimensional accuracy. Then, the custom parts of the car, including the roll cage, had to be designed to meet FIA specifications. This article describes the steps of the 3D scanning method, how the scans are processed, oriented, assembled correctly, and how the deformations of the body frame were detected. In addition, the typical problems encountered during 3D scanning of large objects and their generally applicable solutions are shown. The components of the drivetrain and components of own custom design are also described.

Die Concepts and formability for simultaneous forming of sheet metals and FRPs

Fiber-reinforced plastics (FRPs) are increasingly being used to reinforce steel or aluminum (Al) automotive structure components. Currently, these multi-material applications are realized via three-stage manufacturing, which require the corresponding costs. Thus, a new hybrid forming technology has been developed and will be presented here. It is based on the principle of the hydro-mechanical sheet metal-forming technique and uses a heated thermoplastic FRP material (up to 280°C) in a half melting state as the pressure media to form steel or aluminum sheets. Since the sheet metals are pre-coated with an adhesion promoter, the FRPs are also joined with the sheet metal during this hybrid forming process. In this work, the die and especially the sealing concepts for hybrid forming will be introduced based on different part geometries. The formability of the sheet metals (Nakajima test) at different temperatures up to 280°C, for each two steel and Al alloys, will be presented. The hybrid formed parts were analyzed using optical method and section analysis. Good forming results were confirmed for both sheet metal and FRPs. A vehicle chassis component was successfully hybrid formed using CP-W800 steel and FRP, and a body component was produced using an Al5182 alloy and an FRP.