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Ride is considered to be one of the crucial criterion for evaluating the performance of a vehicle. Automobile industry is striving for improvement in designs to provide superior passenger comfort in Commercial vehicles segment. In Industry, Quarter-car model has been used for years to study the vehicle’s ride dynamics. But due to lower DOF involved in quarter car, the output accuracy is somewhat compromised. This paper aims in development of a 7 DOF full-car Model to perform the ride- comfort analysis for Light Duty 4*2 Commercial Bus using MATLAB Simulink which can be used to tune the suspension design to meet the required ride-comfort criteria. Firstly, experimental data and Physical Parameters are collected by performing Practical Test on commercial Bus on different road profiles. Secondly, a Full Car Mathematical Model with 7 DOF has been developed for a bus using MATLAB Simulink R2018a.

To enhance the crashworthiness of electric vehicles, designing the optimized and safer battery pack is very essential. The deformed battery cell can result in catastrophic events like thermal runaway and thus it becomes crucial to study the mechanical response of battery cell. The goal of the research is to experimentally investigate the effect of mechanical deformation on Lithium-ion battery cell. The paper thoroughly studies the phenomenon of short circuiting at the time of failure. Various experiments are carried on 18650 cylindrical cells (NCA chemistry) under custom designed fume hood. The setup captures the failure modes of battery cell. The loading conditions have been designed considering the very possible physical conditions during crash event. The study has been done for radial compression, semicircular indentation, hemispherical indentation, flat circular indentation and case of three-point bending.

The Electric Vehicles (EV) or Hybrid Electric Vehicle (HEV) has a bunch of electrical/electronic components and its operation give rise to complicated EMI/EMC issues. The Power Electronics Module (PEM), comprising of DC-DC convertor/invertor and Battery Management Unit (BMU), is driving the motor to propel the vehicle. “Battery Pack Module” powers these units through cables. The fast switching of these circuit elements present in the system leads to noise propagation through the cables. These noise signals give rise to various Electromagnetic (EM) related issues in the cable harness of vehicle. It is essential that these cables should not interfere with other electronic components and also does not get effected by external EM disturbances.

Major cause of air pollution in the world is due to burning of fossil fuels for transport application; around 23% GHG emissions are produced due to transport sector. Likewise, the major cause of air pollution in Indian cities is also due to transport sector. Marginal improvement in the fuel economy provide profound impact on surrounding air quality and lightweighting of vehicle mass is the key factor in improving fuel economy. The paper describes robust and integrated approach used for design and development of lightweight bus structures for Indian city bus applications. An attempt is made to demonstrate the use of environment friendly material like aluminium in development of lightweight superstrutured city buses for India. Exercise involved design, development and prototype manufacturing of 12m Low Entry and 12m Semi Low Floor (SLF) bus models.

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.

This work is a part of program on “Development of High Power Density DI, Diesel Engine to Meet US EPA - Tier III Emission norms for off highway and Genset application purpose. This is a 4 Cylinder, TCIC engine delivering 165 Hp @ 2500 rpm. BMEP at max torque comes to be 18 bar giving max cylinder firing pressure of 160 bar. Engine block is a most vital component which has to serve various functions all together. Also design of block for such a high BMEP levels, demands to give a different design strategy required for development of High Performance Engines. In order to reduce overall production cost, several constraints are imposed on design of new block. Design of block is carried out within several design, assembly and manufacturing constraints such as maintain a specific cylinder centre distance, integral oil cooler in the engine block, re-location of camshaft and FIE positions, incorporation of various accessories viz. steering pump, Air Compressor etc.

The paper discusses the methodology for measuring the sound absorption of sound package materials in a different sizes of reverberation chambers. The large reverberation chamber is based on test methods and requirements as per ASTM C423 and ISO 354 standards. Both the test standards are similar and recommend a reverberation chamber volume of at least 125 m3 and 200 m3 respectively for sound absorption measurements from 100 Hz to 5000 Hz. The test sample size requirements are from 5.5 to 6.7 m2 as per ASTM C423 and 10 to 12 m2 as per ISO 354. In the automotive sector passenger car, heavy truck, and commercial vehicle, the parts that are used are much smaller in size than the size prescribed in both the standards. The requirement is to study the critical parameters such as the chamber volume, sample size, reverberation time and cut-off frequency etc. which are affecting the sound absorption property of acoustic material.

Sound Quality (SQ) of brake and clutch pedal assembly plays an important role in contributing to vehicle interior noise and perception of sound. Quiet operation of brake and clutch units also reflects the vehicle built and material quality. Noise emitted from these sub-assemblies has to meet certain acceptance criteria as per different OEM requirements. Not much work has been carried on this over the years to characterize and quantify the same. An attempt has been made in this paper to study the sound quality of brake and clutch pedal assemblies at component level and validate the same by identifying the parameters affecting SQ. Effect on noise at different environmental conditions was studied with typical operating cycles in a hemi-anechoic chamber. The effect of sensor switches integrated within the clutch and brake pedal on sound quality is analyzed. It is found that the operating characteristics of switches drives the noise and SQ.

A methodology for design and development of radiator cooling fan is developed with an objective to improve underhood thermal management. For this purpose an Axial Fan Design Software has been developed which is based on Arbitrary Vortex Flow theory. The software is useful for obtaining initial blade design for the given basic functional requirements in terms of Airflow, Pressure Rise and Speed which defines the operating point of the fan. CFD analysis of the initial fan design is then carried out to predict the fan performance curve. Computation model resembles a fan set up in a wind tunnel. Further, Parametric Optimization is carried out using CFD to meet the functional requirements. A Rapid Prototype sample of the optimized fan design is manufactured and tested in a fan test rig made as per AMCA 210-99 standard to evaluate the fan performance curve and the power consumption.

Automotive electronics is increasingly playing a vital role in all vehicle subsystems. Since an electronic control system needs to be interfaced with the outside world, an electronic smart switch forms a key output interface with various loads such as solenoids, lamps, motors, relays, fans etc. Although integrated circuit based smart-switch semiconductor solutions are provided by all global semiconductor vendors, they prove more often than not to be overdesigned for majority of situations relevant to low end vehicles. They are also generously loaded with standard high-end features like thermal and overload protection which may not always be required. In addition, external transient protection and on-chip diagnostic features lend further complexity to the entire solution.

In order to travel in a chaotic and dynamic environment, an autonomous vehicle requires a motion plan. This motion plan ensures collision free, optimum travel without violating any traffic rules. The optimum solution for path planning problem exists in higher dimensions, however, with the help of useful heuristics the problem can be solved in real time, which is required for real time operation of an autonomous vehicle. There are different well established techniques available to plan a collision free kinematically traversable path. One of such techniques is called conformal Lattice planner. However, the legacy version of conformal lattice planner is not optimized and also is prone to fail under specific dynamic environment conditions. Moreover, the legacy version of conformal lattice planner is also not road aware. Due to this reason it is a semi optimized way to solve the motion planning problem.

This paper introduces xEV Simulator- A MATLAB based simulator platform capable of analyzing EV/HEV powertrain system in both backward and forward modelling. xEV Simulator employs Forward Simulation for drive-cycle performance evaluations and Backward simulation for powertrain component sizing and support xEV powertrain design. The powertrain subsystems are modelled in Simulink. This enables the model based system simulation and further controller prototyping and HiL testing. xEV Offline Simulator GUI enables user to simulate standard EV/HEV configurations with standard drive-cycles. The model parameters of different component subsystems can be configured. The Backward modelling and simulation support the estimation of subsystem values like Propulsion motor, Energy storage, etc., to perform as per the drive-cycle requirement.

The design and development of complete vehicle, understanding of chassis system development process is an important task. Chassis frame of a vehicle is supporting member, both structurally and functionally, to all other chassis aggregate systems viz. suspension, steering, braking system etc. In this paper, a methodology for chassis frame model construction and validation is explained. In present work, chassis frame model is validated in terms of modal parameters and also against static loading conditions. Existing chassis 3D Computer Aided Design (CAD) data was generated using scanning and cloud point data conversion technique. FE model was generated and validated through experimental measurements viz. modal testing, vertical bending, lateral bending, and torsional bending test. Loading and boundary conditions were replicated on the complete FE model in CAE domain and test validation was carried out using appropriate mesh biasing and weld modeling techniques.

Front windscreen wiping test is legal requirement for all motor vehicles as per standards like IS15802:2008 [1], IS15804:2008 [2] in India. This test requires windscreen mock-up/actual vehicle to be tested along with all wiping mechanisms such that minimum percentage areas to be wiped should meet the requirements specified in the IS standard. From manufacturer’s perspective this involves investment of lot of time and cost to arrive at the final design solution in order to meet the wiping requirements. The work scope in this paper is limited to bus category of vehicles. The methodology presented in this paper would enable quick design solutions for bus body builders or manufacturers to meet the wiping requirements specified in IS standard. The methodology presented in this paper was developed to carry out windscreen wiping test through commercially available simulation software.

In today’s scenario, the emission norms are getting stringent day by day due to an increased level of pollution. The world is shifting towards low carbon footprint which made it necessary to adopt efficient technologies with fewer emissions. The hybridization of vehicles has resulted in improved efficiency with lower emissions which can fulfil the near future emission norms. Retrofitting of hybrid components into a conventional IC engine vehicle is so far the best way to achieve better performance both economically and technologically. This research is primarily focused on the design and development of a novel retrofit solution of P3x architecture for the light commercial vehicle. This retrofit solution is different from other hybrid solutions in terms of powertrain. It contains an innovative add-on powertrain along with the existing powertrain. This additional powertrain consists of a pair of helical gears followed by a chain and sprocket as a coupler for traction motor.

The increasing in popularity of Light Commercial Vehicles (LCV) segment is an emerging trend in the commercial vehicle industry. LCVs are very efficient and cost-effective for transportation of materials and good on short distances or loads of lesser weights. Sensing the market potential, many auto companies have developed LCVs recently. Since LCV segment is price sensitive, low cost single cylinder water cooled diesel engine being used as prime mover. High noise & vibration is inherent feature of diesel engine & it is predominant in single cylinder diesel engine. In order to retain low cost of product, less attention is given on overall noise of vehicle. Also, it is challenging to meet the regulatory limits of Pass-by Noise (PBN) for this category of vehicle. This paper is a development work done for pass-by noise reduction of a diesel powered single cylinder LCV vehicle. A prototype vehicle needs to meet the legislative pass-by noise requirement when tested as per IS0 362 / IS 3028.

The technology development in automobiles is progressing towards providing smarter vehicles with increased efficiency and reduced emission. To cater this need, Electric Vehicles (EV) and Hybrid Electric Vehicles (HEV) are slowly thriving in Indian roads. Conversion of existing IC engine powered vehicle to HEV reduces complication in new vehicle development and also results in vehicles with increased efficiency and reduced emission. In order to convert the Conventional Vehicle to Hybrid Electric Vehicle, drive from electric motor was coupled with existing driveline by modifying mechanical systems suitably. Hybrid vehicle includes systems such as electric motors, inverters, high-voltage batteries and electronic control units, which are mounted in chassis members. Being a major load carrying member, any modifications in chassis system may affect the performance of vehicle, therefore it is necessary to evaluate the modified design of chassis members.

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.

The Indian market for battery-powered electric vehicles (xEV) is growing exponentially in the coming years, fueled by tumbling lithium-ion battery prices and favorable government policies. Lithium-ion battery is leading in clean mobility ecosystem for electric vehicles. LiBs efficient and safe performance for tropical climatic conditions is one of the primary requirements for xEV to succeed in India. The performance of LiBs, however, is impacted due to ambient temperature as well as the heat generated within cell due to the load cycle electrochemical reaction. The acceptable operating temperature region for LiBs normally is between 20 °C to 45 °C and anything outside of this region will lead to degradation of performance and irreversible damages. Therefore, understanding the thermal behavior is very crucial for an efficient battery thermal management.

The automotive and related industries are concentrating their efforts on improving comfort by lowering engine, wind, and road noise and vibrations. However, as background noise levels decrease, the squeaks and rattles (S&R) generated by the vehicle's many components become more noticeable and distracting. As a result of the absence of a dominant noise source from a traditional petrol/diesel car, (S&R) noise becomes more dominant than other types of noise in electric vehicles. In this paper, we propose a novel simulation technique for developing a systematic approach to identifying and solving (S&R) problems in vehicle components/sub-assemblies during the primary stage of product development cycle, thus reducing the overall product development time. This paper will present a novel approach to comprehending various methods and Design of Experiments (DOE) techniques used to determine the root cause of (S&R) problems and to solve those using numerical methods.