Design and Static Stress Analysis of Double Wishbone Suspension

Double Wishbone suspension systems are by far the best choice of suspension systems recommended for sports vehicles. It is more stable and stiffer when compared to the other suspension geometries. In this report a brief study of how a double-wishbone suspension system acts under loading conditions when traveling at high speeds is presented, also the forces acting on its components are analysed, and post-processed results are discussed. The geometry of the whole suspension is designed on SolidWorks and analysis is performed on Ansys software. Further the results from the analysis are studied based on material selection and various analysis methods. Finally, the proposed suspension system is concluded safe to use when the values of Equivalent stress, Total Deformation, and Factor of Safety were measured and under threshold limits. Keywords: double wishbone suspension, static structural, suspension system, analysis, deformation, Ansys, stress analysis, FOS, FEA, structural analysis.

DESIGN AND DEVELOPMENT OF REGENERATIVE DAMPERS

Each and every automobile in service or being developed in the industry is benchmarked on the basis of its efficiency in running real conditions. So in our project here we have tried to develop a complete new damper and spring setup which can be used in all sorts of suspension systems and in turn provides a feedback loop of voltage which can then be used charge the batteries and upscale the efficiency of bikes by (5-6)% & and for HUV or Sedans by (2-4)% (can even go higher) depending on the terrain. In this setup we harness the mechanical energy into electrical where earlier it was left as heat and vibrational losses. This setup is as cost effective as the earlier dampers where as providing an efficient output in minimal cost increase due to its novelty. The other Features include Electronic height adjustment & on demand suspension softness or stiffness. Keywords: Dampers, Automobile, Electromagnet, EV (Electric vehicle), Voltage, Magnetic flux, Suspension

Identification of Vehicle System Dynamics from the Aspect of Interaction between the Steering and the Suspension Systems

Steering and suspension systems of a motor vehicle have very important mutual connections that have direct influence on a vehicle’s steerability, stability, comfort and life expectancy. These mechanical and functional couplings cause an intensive interaction between the two mentioned vehicle systems on a geometrical, kinematical and dynamical level. This article presents a study on nonparametric identification of dynamic interaction between the steering and the suspension system of a passenger vehicle. A specific methodology for experimental research in on-road conditions was designed that was in line with the research objectives and the applied measuring system. Experimental data were acquired for a curvilinear drive, with different constant driving speeds and on different roads. A multiple input/multiple output model for identification of the vehicle dynamics system from the aspect of interaction between the steering and the suspension system was developed. The analysis of experimental data was realized with the selection of a corresponding identification model, decoupling of model inputs and conditioned spectral analysis. The results of the conditioned spectral analysis of experimentally obtained data records indicate the level of interaction between the observed input and output parameters of the steering and the suspension systems to be in the frequency range below 30 Hz.

Evaluation of Dynamic Load Reduction for a Tractor Semi-Trailer Using the Air Suspension System at all Axles of the Semi-Trailer

The air suspension system has become more and more popular in heavy vehicles and buses to improve ride comfort and road holding. This paper focuses on the evaluation of the dynamic load reduction at all axles of a semi-trailer with an air suspension system, in comparison with the one using a leaf spring suspension system on variable speed and road types. First, a full vertical dynamic model is proposed for a tractor semi-trailer (full model) with two types of suspension systems (leaf spring and air spring) for three axles at the semi-trailer, while the tractor’s axles use leaf spring suspension systems. The air suspension systems are built based on the GENSYS model; meanwhile, the remaining structural parameters are considered equally. The full model has been validated by experimental results, and closely follows the dynamical characteristics of the real tractor semi-trailer, with the percent error of the highest value being 6.23% and Pearson correlation coefficient being higher than 0.8, corresponding to different speeds. The survey results showed that the semi-trailer with the air suspension system can reduce the dynamic load of the entire field of speed from 20 to 100 km/h, given random road types from A to F according to the ISO 8608:2016 standard. The dynamic load coefficient (DLC) with the semi-trailer using the air spring suspension system can be reduced on average from 14.8% to 29.3%, in comparison with the semi-trailer using the leaf spring suspension system.

CONTACT INTERACTION OF A TORSION SHAFT WITH A SPLINED BUSH IN ELASTICALLY PLASTIC DEFORMATIONS

Torsion shafts are the main elastic element of the suspension systems of a large number of vehicles. To simulate their reaction to the action of torque, the stress-strain state is analyzed taking into account the contact interaction with the spline sleeve. The features of the distribution of contact pressure between these bodies are established. The nature of stress concentration in the splined hollows of the shaft head is determined. Models and research methods have been developed that make it possible to develop recommendations for design decisions in the design of vehicle suspension systems. The factors are determined that ensure the strength of the torsion shaft at the values of its head diameters close to the diameters of the torsion shaft stem. In the case under consideration, this factor is firstly strength of the torsion shaft head. In particular, it was found that during manufacturing operations there are significant plastic deformations and contact loads in the heads of torsion shafts. This factor is decisive in substantiating the design parameters of torsion shafts. Keywords: torsion shaft; contact interaction; stress-strain state; elastically plastic deformation; suspension system

ANALYTICAL REVIEW OF RESEARCH AND DEVELOPMENT OF ELEMENTS OF SUSPENSION SYSTEMS OF ARMORED VEHICLES OF LIGHT CATEGORY BY MASS (REVIEW ARTICLE)

The analysis of materials on the design of light armored vehicles is carried out. The main mathematical models for modeling dynamic processes, stress-strain state in the system "combat module - hull - suspension" are considered. The publications on the design of suspension torsion bars are analyzed. To date, the analysis and synthesis are not united by a single generalized parametrical description, which would cover both technical solutions of elements of suspension of light armored vehicles, modes of motion of these machines, and properties of materials of the elements under study, and requirements for tactics and technical characteristics in general. That is, there is no corresponding theoretical base for solving the problems of parametric synthesis of elements of suspension systems, and existing mathematical models need to be improved. Therefore, the main tasks that need to be solved or improved by existing solutions are set. Also, such developments are needed that would take into account technical solutions, processes and conditions, stages of manufacture, operating conditions and combat use, that is, those that would reflect all stages of the life cycle of the elements of suspension systems for light armored vehicles. Keywords: light armored vehicle; tactical and technical characteristics; torsion bar; suspension systems; sprung part; suspension; stress-strain state

PROSPECTIVE ELECTROMECHANICAL SHOCK ABSORBERS

The article considers the issue of the system of the running gear of a high-speed electric train with a body inclination and the system of oscillation recovery. The authors considered the main suspension systems of the electric train body, which are currently used. The main problems of these suspension systems were put forward. Attention is paid to the use of air-spring suspension. The pipe suspension of the VL80 electric locomotive and the construction of the trolley itself are considered. The basic criteria of an estimation of efficiency of perspective electromechanical shock-absorbers on which the comparative characteristic is carried out are defined. The article describes a promising electromechanical shock absorber based on a synchronous linear motor, which can provide both body tilt and damping and recovery of oscillations. The functional scheme of control of two synchronous linear motors which are established on one cart is considered. The operation of the control system of synchronous linear motors is described. The design of a linear DC motor with permanent magnets is described. The functional control scheme of two linear DC motors with permanent magnets is considered. The design of the electromechanical shock-absorber of the Bose company is resulted. The comparative characteristic of three perspective electromechanical shock-absorbers on six criteria is carried out. Conclusions are made and an electromechanical shock absorber is selected, which provides the basic needs of rolling stock.