Chassis Structures Research Articles

Revitalizing vehicle innovation: Exploring electric car chassis structures through finite element analysis

The increasing number of motor vehicles contributes significantly to air pollution, resulting in global environmental degradation due to CO2 emissions. Electric cars offer an environmentally friendly solution to this issue. Vehicle chassis plays a critical role as the support structure for various components. This study aims to design an optimal electric vehicle chassis considering weight, safety, and strength aspects, utilizing von Mises stress analysis to assess stress levels and safety factors. The research focuses on determining the chassis' safety factor and stress distribution, employing alloy steel material and subjecting it to a 5000 N force using finite element analysis (FEA). Analysis results show von Mises stress ranging from 0.002 N/mm^2 to 167.549 N/m^2, displacement ranging from 0.000 mm to 1.812 mm, strain ranging from 0.000 to 0.0001, and safety factors ranging from 2.327 to 371,181.531. Consequently, overall simulation on the chassis is targeted to run optimally, which fulfills the objectives of this research.

In-series vs. in-parallel: The role of cargo-motor connectivity in transport by ensembles of cytoskeletal motor proteins.

The movement of the cytoskeletal molecular motor proteins dynein and kinesin on microtubule networks facilitates the complex intracellular organization of eukaryotic cells. Ensembles of these motors are a prevalent feature of cytoskeletal transport, indicating possible synergistic effects of their use for intracellular organization. While the force output of individual motors is well studied, the mechanisms governing emergent force generated by multiple motors acting as an ensemble remains unclear. Determining the fundamental mechanisms controlling the interaction and integration of the forces produced by these motors at the nanoscale is essential to understanding the broader system of intracellular transport. Using total internal reflection fluorescence (TIRF) microscopy, we are investigating the role of the spatial arrangement of motors in an ensemble with a particular emphasis on the connectivity between motors and their cargo. Using motors purified from yeast and the nanoscale construction techniques of DNA origami, we create programmable chassis structures in which multiple cytoplasmic dyneins or Kip2 kinesins are arranged with independent, “in parallel” connections to a resistive cargo load or, in contrast, are arranged with a single, “in series” shared cargo connection. We expect the use of these chassis will allow us to determine the mechanisms behind the structural integration of the piconewton forces produced by cytoskeletal molecular motors within ensembles, ultimately providing insight on how the individual connectivity of motors to one another and their cargo affects load-sharing, force integration, and the resultant emergent motility of the motor ensemble.

Integrated topology and packaging optimization for conceptual-level electric vehicle chassis design via the component-existence method

Conventional vehicle architectures are undergoing significant transformation as automakers embrace electrification. With increased emphasis on lightweight structures design and efficient packaging of new electric powertrains, numerical tools are now essential to help solve these complex material and component distribution problems. To address these challenges, methods for integrated topology and packaging optimization (iTOPO) have been developed to couple these problem statements and form dynamic component-structure interactions. In this work, a component-existence approach is used for conducting iTOPO of self-contained electric vehicle chassis structures to demonstrate the benefits and scalability of this emerging methodology. Examples focus on incorporating simplified components for battery modules and electric motors within the underlying vehicle structure, integrating up to 43 components simultaneously in a 3D design domain. Here, discussion highlights the development of unique integrated layouts, methodology tunability, and practical insights of the formed component-structure interactions. iTOPO results are also compared to equivalent topology-only problems and show less than a 10% difference in compliance despite the addition of various complex integration requirements (e.g. multiple geometries, packaging symmetry).

Stress Optimization of F1 Car Chassis Using FEA Technique

Abstract: Chassis is the primary structural component of an automobile. It is the main supporting structure of a vehicle to which all other systems like braking, suspension and differential are attached. In this project, a methodology for F1 Car chassis design and structural stability analysis is presented. A literature study is carried out to review various existing designs of vehicle chassis, latest innovations and advanced materials used to manufacture the same. The various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle are understood. After completing literature study, several findings are listed in a systematic manner, by providing ample arguments to justify each of them. The pro-con analysis is conducted to evaluate merits and demerits of each alternative type of chassis and the material to manufacture it. In this research work, the material are Aluminum Alloy and AISI1144 Carbon steel. Analysis both material in different parameters which are essential for any ideal chasiss such as various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle. The most essential design criteria are derived by selecting different materials which then acts as important guidelines during the actual design process. Structural chassis frame is designed as per the design criteria, using the CAD software CATIAV5R19 and the structural stability of the same is tested and analyzed using ANSYS Workbench 19.0 software. From the results of these analysis tests the static structural stability of the design is confirmed. Keywords: Ansys Workbench, Design for Material, Chassis and Carbon Steel.

Effect of the rotor cage chassis on inner flow field of a turbo air classifier

AbstractAs the connection between the center of rotor cage and the coarse powder collecting cone, rotor cage chassis of the turbo air classifier directly influences airflow movement in the classifier. In order to study the effect of rotor cage chassis on the inner flow field of a turbo air classifier, the flow fields of four rotor cage chassis structures with different opening size are simulated and compared using ANSYS‐FLUENT 17.0. The simulation results show that there is “bypass flow” phenomenon for the classifier with the open rotor cage chassis, compared with the closed rotor cage chassis. The “bypass flow” phenomenon can change the airflow velocity distribution of the annular region. For the open rotor cage chassis, its opening size has no significant effect on the flow field distribution and the airflow velocity. However, the open or closed rotor cage chassis has great effect on the flow field distribution and the airflow velocity. The calcium carbonate classification comparative experiments are carried using the open and closed rotor cage chassis structures. The experiment results show that the open rotor cage chassis can decrease the cut size, and the closed rotor cage chassis can improve the classification accuracy.

Predicting tolerance on the welding distortion in a thin aluminum welded T-joint

Welding is a widely accepted process used in the assembly of aluminum chassis structures in the automotive industry. Finite element analysis (FEA) is usually adopted to predict distortions caused in the welding process. However, only nominal distortions result from FEA simulations. Welding distortions could be more accurately predicted by introducing the prediction of tolerances due to a modification of the input parameters. The aim of this work is therefore to introduce the tolerance evaluation in the FEA model, by varying the welding input parameters (geometrical and dimensional tolerances on the parts, heat input…). To find the most suitable FEA model to investigate welding process tolerance, three FEA models are compared: one is the thermo-elastic-plastic (TEP) model, and two are based on the inherent strain method. The case study uses a thin (2 mm) aluminum T-joint, which is commonly used in automotive chassis assembly. Results deriving from FEA simulations were compared with experimental data. Among the various input parameters affecting the welding process, the authors combined the dimensional tolerance on the plate thickness with the variability of the heat input. The results provided a tolerance range value for the angular distortion of the T-joint.

Experimental and modelling techniques for hot stamping applications

Hot stamping techniques have been developed for the production of complex-shaped components since the 1970s, increasingly used for the automotive industry. The application of these techniques includes hot stamping of boron steel for critical automobile safety components, and solution heat treatment, forming and cold die quenching (HFQ®) for forming complex-shaped high strength aluminium panels of automobile bodies and chassis structures. The developed forming techniques need dedicated experimental testing methods to be improved for characterising the thermomechanical behaviour of materials at the hot stamping conditions, and advanced materials modelling techniques to be developed for hot stamping applications. In this paper, requirements for thermomechanical tests and difficulties for hot stamping applications are introduced and analysed. The viscoplastic modelling techniques have been developed for hot stamping applications. Improved experimental methods have been proposed and used in order to obtain accurate thermomechanical uniaxial tensile test data and determine forming limits of metallic materials under hot stamping conditions.

Industrial based volume manufacturing of lightweight aluminium alloy panel components with high-strength and complex-shape for car body and chassis structures

To achieve the high volume manufacture of lightweight passenger cars at economic cost as required in the automotive industry, low density materials and new process route will be needed. While high strength aluminium alloy grades: AA7075 and AA6082 may provide the alternative material solution, hot stamping process used for high-strength and ultrahigh strength steels such as boron steel 22mnb5 can enable the volume manufacture of panel components with high-strength and complex-shape for car body and chassis structures. These aluminium alloy grades can be used to manufacture panel components with possible yield strengths ≥ 500 MPa. Due to the differences in material behaviors, hot stamping process of 22mnb5 cannot be directly applied to high strength aluminium alloy grades. Despite recorded successes in laboratories, researches and niche hot forming processes of high strength aluminium alloy grades, not much have been achieved for adequate and efficient volume manufacturing system applicable in the automotive industry. Due to lack of such system and based on expert knowledge in hot stamping production-line, AP&T presents in this paper a hot stamping processing route for high strength aluminium alloys been suitable for production-line development and volume manufacturing.

Editorial: Secondary Metabolism. An Unlimited Foundation for Synthetic Biology.

The foundations of synthetic biology rely on the concept that all living systems are constituted by functional and structural modules that could be rationally engineered to build organisms that are not easily generated by evolution. However, the cellular complexity and metabolic diversity found in organisms present both a significant challenge and opportunity to foster this interdisciplinary scientific area. Secondary metabolism is a group of biological processes which are dispensable for cell growth. In microorganisms such as fungi and filamentous bacteria, secondary metabolism is an important source of biologically active compounds (Leitao and Enguita, 2014). The genes encoding for the enzymes involved in secondary metabolism are frequently clustered together displaying a modular organization, constituting a perfect target for the application of synthetic biology principles with an almost unlimited potential for the construction of new cell factories, which is mainly constrained by the knowledge of the working rules of the functional blocks governing the biosynthesis of a particular metabolite. More than 35 years after the first seminal ideas by Hopwood, who hypothesized about the possibility of a rational design of new antibiotics based on the combination of biosynthetic genes (Hopwood and Chater, 1980), secondary metabolites are gaining a new relevance. Modern genetic techniques have enabled complete genome sequences of secondary metabolite producers to be thoroughly and rapidly interrogated to uncover loci relevant for metabolite biosynthesis. The developed genome editing and engineering techniques are paving the way for rational pathway design and construction, modifying a genotype with the main objective of giving rise to a desired phenotype (Paddon et al., 2013; Paddon and Keasling, 2014; Hoynes-O'connor and Moon, 2015). Recent applications of genome editing techniques such as TALE nucleases or CRISPR-Cas9 in the rational engineering of primary and secondary metabolites are an excellent example of the potential in this area (Huang et al., 2015; Lv et al., 2015; Wu et al., 2015). This Frontiers research topic was proposed to compile new trends for the application of synthetic biology methods and protocols to the field of secondary metabolites. We are extremely grateful to all the authors that have contributed to enrich the contents of the research topic. The topic contributions include six articles, covering wide aspects of secondary metabolism in organisms ranging from filamentous bacteria to microalgae. Two excellent articles by Mattern et al. and Chavez et al. describe applications of synthetic biology principles for the manipulation of secondary metabolite biosynthesis in filamentous fungi. Interestingly, the article by Chavez et al. also explore the idea of genome mining to search and explore new metabolites in filamentous fungi isolated from extreme environments. Several practical applications of synthetic biology principles were discussed by Giessen and Marahiel. In this article, the authors present a large repository of modular catalytic enzymes able to modify cyclic dipeptides, and demonstrate how combinatorial chemistry can be applied to custom design new molecules with improved biological activities. Moreover, the work by Gressler et al. also included in the research topic, describes a high-performance system for heterologous expression in Aspergillus terreus based on the tetA promoter and the DNA-binding domain of its cognate transcription factor TetR. As a proof of concept, the authors used the system to express the polyketide synthase-encoding gene osrA, and demonstrated its catalytic activity. Other interesting topic discussed by Beites and Mendes reflects the increasing number of genomic data generated by the bacterial genome sequencing projects which can be further exploited as an unlimited source of metabolic diversity. In fact, following the author's ideas, several biosynthetic clusters for secondary metabolites present reduced or no expression (also known as “cryptic” clusters), constituting a pool of novel metabolites waiting to be mined and characterized. Within this context, the article described rational strategies and tools to be used in the development of chassis structures for the heterologous expression of biosynthetic gene clusters in filamentous bacteria. Finally, the topic also includes an article by Gimpel et al. which discusses the strategies for rational metabolic engineering of microalgae, a very promising tool for the production of several products including biofuels, carotenoids, and bio-hydrogen. We hope that this research topic will be interesting and useful to the general audience of Frontiers in Microbiology journal, and that the treated topics act as crystallization nuclei for new ideas and future applications of the principles of synthetic biology to the design of new secondary metabolites with improved biological activities.

Durability prediction for automobile aluminum front subframe using nonlinear models in virtual test simulations

This research work presents fatigue life evaluation techniques for an automotive vehicle aluminum front subframe using virtual test simulation technology with nonlinear suspension components model. The technology was used for improving the accuracy of the polynomial model used in conventional analysis. The proposed nonlinear suspension components models were developed using direct approach. The effects of the nonlinear elements on the prediction of the fatigue life were also analyzed. Actual aluminum front subframe was tested using half-car road test simulator to verify the accuracy of the models. It was found that the proposed nonlinear models yield more accurate results than conventional polynomial models. The proposed virtual test simulation technology with nonlinear suspension components model can be used to predict fatigue life for vehicle chassis structures more accurately.

Effect of welding on the fatigue strength of welded joints using the GMAW process in transformation induced plasticity steels (TRIP) used in the automotive industry

ABSTRACTWelding of TRIP steels are one of the technical challenges in the successful application of AHSS in chassis structures. Gas Metal Arc Welding (GMAW) is a common welding process used in the automotive industry, for joining mild steels. TRIP steel; however, do not offer the same ease of welding, and process control welding parameters is more critical. The welding parameters window represents the range of acceptable process parameters, primarily control of heat inputs, to obtain an acceptable weld. As a result, the effects of the heat input variations are greater and TRIP steel has a narrower welding parameters window in which acceptable welds can be made. Mechanical properties of the lap joints of TRIP 780 steel 2.8 mm thickness was analyzed, fusion welds were evaluated using fatigue tests on these joints for different heat inputs. Fatigue testing was conducted under a different number of nominal stress ranges to obtain the S/N curves of the weld joints.

The influence of the laser and plasma traverse cutting speed process parameter on the cut-edge characteristics and durability of Yellow Goods vehicle applications

The durability of steel components produced for service as Yellow Goods vehicle applications, are primarily influenced by the condition of their thermal cut-edges. The chassis structures of such demanding applications are manufactured with laser and plasma cut-edges left exposed after final fabrication. Over prolonged periods of service, defects formed during the cutting processes can act as initiation sites for fatigue cracks, resulting in eventual structural failure of the application. The traverse cutting speed parameter was altered for cuts performed using laser and plasma cutting processes to ascertain the changes in critical surface characteristics and microstructural properties in close proximity to the cut-edge. It was the damage formed during each cutting process which directly influenced the fatigue life of the resulting cut-edges. Manipulating the critical traverse cutting speed process parameter resulted in the generation of cut-edges that are near to optimum with the minimum number of cut-edge defects.

Design of Automotive Metal and Composite Chassis Structures

Design of Automotive Metal and Composite Chassis Structures

Design of Automotive Metal and Composite Chassis Structures

This paper reviews recent patents covering automotive metal and composite chassis structures. Automotive chassis are very complex structures and the variety of different types is vast. This paper attempts to reveal modern chassis design looking at composite structures, bonding methods, front sub-frames, complete space-frames, uni-body, integral frame and monocoque structures. Automotive chassis designs have had considerable developments in recent years. This is attributed to recent legislation taking particular interest in after service disposal and more prominently crash, impact and occupant safety. Automotive manufacturers continue to develop new, innovative and novel approaches to achieving rigidity and stiffness in torsion and bending to achieve optimal suspension geometry, safety and occupant comfort. Recent patents in automotive chassis design refer mainly to stiffening support structures, composite structures, retractable roofs and by far the most common, front crash sub frames. Keywords: Chassis, metal chassis, composite chassis, bonded chassis, crash box, sub frames, spaceframe, monocoque, heat affected zone, epoxy resins, Cycom 977, honeycomb sandwich material, resin transfer moulding, RTM, Cabriolet space-frame, CNC bending, computer controlled welding, fibre-reinforced plastic sheets, multi utility vehicle, Audi spaceframe (ASF) chassis, resilient aluminium alloy, frontal collision, FRP COMPOSITES, torsion beam, Rear sub-frame, Shock absorbing crash element, Honeycomb core profile, noise and vehicle harshness

Modern lightweight steel body and chassis structures

Weight and cost reduction have been central issues in the automotive industry for many years. Against the background of the CO2 debate and rising safety requirements, these goals demand innovative solutions from automotive manufacturers and suppliers, above all in the weight-intensive body and chassis areas. ThyssenKrupp Umformtechnik has focused on development in this field.

Fatigue strength of laser beam welded thin steel structures under multiaxial loading

The multiaxial fatigue behaviour of thin laser beam welded tube–tube specimens of the structural steel St35 was assessed according to the methodology of the fictitious weld root radius of r f=0.05 mm and the application of the Effective Equivalent Stress Hypothesis (EESH), especially considering the fatigue life reducing influence of out-of-phase loading in comparison to in-phase loading. The results are applicable for the fatigue design of laser beam welded car body and chassis structures of thin steel sheets ( t<3 mm).

Dynamic design of automotive systems: Engine mounts and structural joints

Dynamic design and vibro-acoustic modelling issues for automotive structures are illustrated via two case studies. The first case examines the role and performance of passive and adaptive hydraulic engine mounts. In the second, the importance of welded joints and adhesives in vehicle bodies and chassis structures is highlighted via generic ‘T’ and ‘L’ beam assemblies. In each case, analytical and experimental results are presented. Unresolved research issues are briefly discussed.

New applications of topology optimisation in automotive industry

Topology optimisation is used for obtaining the best layout of vehicle structural components to achieve predetermined performance goals. In this research, the structural topology optimisation based on density formulation is employed. The topology design problem is formulated as a general optimisation problem and is solved by mathematical programming methods so that the objective and the constraint functions can be any structural performance measure. Design variables for this formulation parameterise the material of each element. NASTRAN-based finite element codes are employed for the response analyses. Traditionally, the topology optimisation is used in body and chassis structures for determining optimal structural layouts. In this research, new applications including weight reduction, manufacturing process selection, weld and bead pattern designs for three-dimensional automotive examples are presented and discussed.

Chassis dynamics related to a low-cost magnetically suspended vehicle

Interaction introduced by the chassis structure of a magnetically suspended vehicle can deteriorate the performance of the suspension controllers. The paper presents a comparison between two particularly simple chassis structures and the design constraints introduced by misaligned tracks.

Effect of step duration on the evaluation of the fatigue limit of welded steel structures

In order to reduce the design weight and ensure high reliability of welded chassis structures of transport machines, stringent requirements are imposed on the methods of evaluating the fatigue strength of these structures. It is well known that in the majority of cases the development of reliable calculation methods greatly lags behind the development of efficient (from the design and technological points of view) members of chassis structures. Experimental methods are therefore of special importance in this case [i].