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A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers.

The Indian automotive industry is striving towards more safe and durable vehicles. A need was felt to study the effect of changes in axle static loads on fatigue life of the axle components. Also, there was a need to develop generic test method, as there are no test standards or generic methods available in public domain for fatigue testing of commercial vehicle axles. The study was carried out to check direct effect of change in axle loads on various connections on axle, effect of suspension configuration and force distribution, Vehicle dynamics, etc. In this paper, an India specific generic load spectra was evaluated for accelerated laboratory validation. Paper discusses the methodology as; study of heavy commercial vehicle systems, road load data collection on identified test vehicles w.r.t. test matrix finalized, India specific test loads and load spectra development, normalization of axle load spectra w.r.t to static axle weights and arriving at test guidelines.

With the recent development in virtual modelling and vehicle simulation technology, many OEM’s worldwide are using digital road profiles in virtual environment for vehicle durability load prediction and virtual design evaluation. For precise simulation results, it is important to have the tire digital twin which is the realistic representation of tire in the virtual environment. The study comprises of discussion about different types of tire models such as empirical, solid model, rigid ring model and flexural ring models such as Pacejka, MF Swift, CD tire, F tire etc. and also the complexity involved in development of these tire models. Generation of virtual tire model requires highly sophisticated test rigs as well as vehicle level testing with Wheel Force transducers and other vehicle dynamics sensors. The large number of data points generated with testing are converted in standard TYDEX format to be further processed in various software tool for virtual model generation.

Energy dispersive X-ray fluorescence (EDXRF) analysis have made it possible to conduct elemental analysis on a variety of fields, including those with environmental, automotive, geological, chemical, pharmaceutical, archaeology, and biological origins. The ability of EDXRF to deliver quick, non-destructive, and multi-elemental analytical findings with increased sensitivity is of great importance. It is a vital tool for quality control and quality assurance applications. Thus, EDXRF plays an important role to compare batch-to-batch products for meeting quality standards. This paper presents application of EDXRF as an effective tool for quick qualitative and quantitative evaluation of given samples.

In present scenario, tyre industry is more focused on providing maximum extent of NVH comfort to passengers by improvising the tyre design. Noise contribution from the tyres is classified in to three regions, viz., structure-borne (tyre vibrations), air-borne (tread pattern) and cavity noise (air cavity). In general, a Finite Element (FE) model of tyre provides an inherent advantage of analyzing tyre dynamic behavior. In this paper, an attempt was made to develop a three-dimensional FE tyre model and validate the same through experimental approach. The CAD Model of the tyre was generated through 3D image scanning process. Material property extraction of tyre was carried out by Universal Testing Machine (UTM) to generate Finite Element (FE) model. For validation of tyre FE model, Experimental Modal Analysis (EMA) and Noise Transfer Function (NTF) were conducted.

Tire failure is identified as a major cause of accidents on highways around the world in the recent past. A tire burst leads to loss of control of the vehicle which ends up in a catastrophe. There are various factors which are accounted for a tire burst. Heat buildup, aging of tire and cracks on tires are the major ones which are identified. A superior ability of the tire to dissipate the heat generated during operation is a major factor which prevents a tire failure. Other factors such as ambient temperature, inflation pressure etc. contributes to heat buildup which may ultimately result in tire failure. A combination of these factors might manifest as a tire failure at high speeds, the latter being an immediate cause of heat buildup. A dormant crack in the tire might develop if the temperature and pressure conditions are favorable, thus giving away at the weakest point. With regard to the temperature conditions, road conditions, inflation pressure checks etc.

Air suspension systems had been introduced in automobiles since 1950s. These systems are being explored to improve the ride comfort, handling stability and also serve as a medium for better cargo protection. These system are well developed for buses and high end passenger sedans, also have feasibility for adapting for wide range of configurations of suspension system and axle. Passenger cars and Sports Utility Vehicle (SUV) pickup category of vehicle offers different challenges such as space availability, spring selection and characterization that need to be addressed for successful implementation of air suspension in these category vehicles. This work defines methodology to implement air suspension system in SUV Pickup category vehicle. Paper work includes concept study, mathematical co-relation, and prediction of air spring characteristics and integration of experimental and analytical tool for development of air suspension system.

Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.

Design of vehicle for targeted customer usage is one of the key steps during vehicle development process. Due to globalization, most of vehicles, aggregates, components are being designed for global market considering worldwide load spectrum. Generally for doing this the vehicle response is being measured for different markets but this process is very time consuming. Also for getting these vehicle dependent parameters, exercises need to be repeated on each type/class of vehicle. So there is a need to have a robust procedure, tools which will helps OEM’s to predict the loads, vehicle response for different market segments at an early stage of vehicle development program using the inputs which are vehicle independent. The solution for this could be to use vehicle independent input such as digitized road profiles (2D or 3D) of target customer markets in combination with proper MBD simulation tools.

Designers and analysts need to compare and conduct synthesis for selection of materials based on their properties involving simulation, optimization and correlation with test data. An example is that of acoustic material properties such as random and normal incidence sound absorption coefficient and sound transmission loss. The international test standards necessitate having standard operating procedures for characterization of these materials. This procedure is quite involved and addresses steps including test data acquisition, post processing, calculations, classification, report generation and most importantly, storage of such innumerable material properties in a structured manner to facilitate ease of retrieval and updating of properties. It is also highly desirable to have a synergy of the databank directly with simulation tools. Further, all of these steps need to be accurate, non-speculative and quick.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.