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The Light commercial vehicle (LCV) is primarily used for the last mile delivery and it hold the volume share of around 61% in the commercial vehicle segment. The last mile delivery services have seen a massive surge after the CoVID 19 pandemic resulting is the increase sale of LCV in last few years and is expected to grow further by 8-11% in the coming years. However, city logistic is also responsible for most pollution and noise in the city. Hence, policymakers are aiming to reduce carbon footprint by promoting the use of Electric vehicle by providing incentive to automakers though schemes like FAME I and FAME II. In order to effectively reduce the carbon footprint within city it is important to increase the use of new electric vehicle and convert the old polluting vehicles to electric. Hence, a retro fitment solution for converting used LCV to electric can help in reducing emission as well as noise pollution. Later the same solution can be offered as OE fitment solution.

India is one of the largest markets for the automobile sector and considering the trends of road fatalities and injuries related to road accidents, it is pertinent to continuously review the safety regulations and introduce standards which promise enhanced safety. With this objective, various Advanced Driver Assistance Systems (ADAS) regulations are proposed to be introduced in the Indian market. ADAS such as, Anti-lock Braking Systems, Advanced Emergency Braking systems, Lane Departure Warning Systems, Auto Lane Correction Systems, Driver Drowsiness Monitoring Systems, etc., assist the driver during driving. They tend to reduce road accidents and related fatalities by their advanced and artificial intelligent fed programs. This paper will share an insight on the past, recent trends and the upcoming developments in the regulation domain with respect to safety.

Range of an electric vehicle is one of the most prominent decisive factors for a person willing to buy an electric vehicle. In this paper an algorithm is developed to estimate the load carried by the truck or passengers in case of a bus and accordingly switch between ECO, ECO+, Normal, Power, and Power+ modes. This is similar to the ECO/Power switches available in the vehicles, but here auto switching is done to reduce driver dependability and allow vehicle to operate in 5 different modes without driver intervention. Optimum utilization of available torque is done for efficient operation of the vehicle in all load and road conditions. The model-based software development using MATLAB Simulink is used to develop an algorithm which will switch to Power or Power+ torque mode if the vehicle is fully laden or if the vehicle is going on a steep hill, whereas the algorithm will switch to ECO+ or ECO mode if the vehicle is empty or carrying less load.

Electric vehicles have a limitation of limited range and long charging time. Energy optimization plays a very crucial role in determining the range of an electric vehicle. The innovative system proposed here gives the opportunity to reduce energy wastage and efficiently direct the electrical energy to improve the driving range of a 9 meter AC electric bus. The high voltage air conditioner unit alone consumes more than 40% of the electrical energy stored in the traction battery which reduces the driving range of the electric bus drastically. The proposed system optimizes the air conditioner utilization to direct cool air only in areas where passengers are present. Buses do not always run on full capacity, when there are less number of people in the bus the system detects the locations of the passengers using sensors and occupant detection algorithm, this enables the controller to identify the areas where cooling has to be focused and where cooling can be reduced or stopped.

In today’s automobile industry refined NVH performance is a key feature and of high importance governing occupant comfort and overall quality impression of vehicle. In this paper interior noise and vibration measurement is done on one of the light truck and few dominant low frequency noise booms were observed in operation range. Modal analysis was done for the cabin at virtual as well as experimental level and few modes were found close to these noise booms. Vibrations were measured across the cabin mounts and it was found that the isolation of front mounts is not effective at lower frequencies. Taking this as an input, the mount design was modified to shift the natural frequency and hence improve the isolation behavior at the lowest dominant frequency. This was followed by static and dynamic measurement of the mounts at test rig level to characterize the dynamic performance and stiffness conclusion.

Passenger vehicles are used as one of the frequently used and versatile mode of transport. Commercial buses cater to short to long distance travel for city as well as highway applications. Thus, passenger ride comfort becomes paramount for the salability of the vehicle. Generally, it is observed that the rear seat experiences the worst ride comfort characteristics due to rear overhang and pitching characteristics of buses. Therefore the objective of this project is to improve the rear seat vibrations of passenger bus by tuning damper characteristics. Shock absorbers, being a low cost and easily interchangeable component is tuned first before optimizing other suspension parameters. The methodology is as follows: first, a 4 degree of freedom mathematical model is created on MATLAB Simulink R2015a environment. Time domain data is obtained by road load data analysis and used as an input for the mathematical model.

In cylinder combustion and emission characteristics are dependent on piston bowl geometry design. In-cylinder fuel air mixing and flame front movement are influenced by piston bowl shape and design. These phenomena in turns affect the combustion behavior and the power developed by the diesel engine. In this study piston bowl geometry optimization of a LMD diesel engine is carried out to improve the torque and BSFC output at low end rated operating zones. The optimized bowl geometry is also incorporated in the engine and validated on the test bed. In this work, a commercially available CFD code AVL FIRE is used for combustion simulation and bowl geometry optimization. The validation of in-cylinder combustion simulation of a 2 liter Turbocharged LMD BS-VI diesel engine with base piston bowl geometry is carried out with the available test data.

Ride Comfort forms a core design aspect for suspension and is to be considered as primary requirement for vehicle performance in terms of drivability and uptime of passenger. Maintaining a balance between ride comfort and handling poses a major challenge to finalize the suspension specifications. The objective of this project it to perform ride- comfort analysis for a commercial truck using MATLAB Simulink. First, benchmarking was carried out on a 4x2 commercial truck and the physical parameters were obtained. Further, a mathematical model is developed using MATLAB Simulink R2015a and acceleration- time data is collected. An experimentation was carried out on the truck at speeds of 20 kmph, 30 kmph, 40 kmph and 50 kmph over a single hump to obtain actual acceleration time domain data. The model is then correlated with actual test over a single hump. This is followed by running the vehicle on Class A, B & C road profiles to account for random vibrations.

Frontal crash is the most common type of accidents in passenger vehicles which results in severe injuries or fatalities. During frontal crash, some frontal vehicle body has plastic deformation and absorbs impact energy. Hence vehicle crashworthiness is important consideration for safety aspect. The crash box is one of the most important parts in vehicle frontal structure assembly which absorb crash energy during impact. In case of frontal crash accident, crash box is expected to be collapsed by absorbing crash energy prior to the other parts so that the damage to the main cabin frame and occupant injury can be minimized. The main objective of this work is to design and optimize the crash box of passenger vehicle to enhance energy absorption. The modeling of the crash box is done in CATIA V5 and simulations are carried out by using ANSYS. The results show significant improvement in the energy absorption with new design of the crash box and it is validated experimentally on UTM.

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.

In the modern era of commercial vehicle industry, passenger and driver comfort is one of the major parameters that improves vehicle running time which leads to fleet owner’s profitability. Air conditioning system is one such system whose primary function is to provide the required cooling inside the cabin in hot weather conditions. An Air-conditioned truck cabin creates a comfortable environment for the driver which increases his efficiency and reduces fatigue. An AC compressor consumes power directly from the engine affecting fuel economy and vehicle performance. With ever increasing demand for energy efficient systems and thermal comfort in automobiles, AC systems should be able to deliver the required cooling performance with minimum power consumption. Therefore, reducing AC power consumption in vehicles is one of the key challenges faced by climate control engineers.

The Mounting system of component plays a major role in determining the structural durability, compatibility and synchronization of the systems with respect to each other. The major function of Engine mounts is to isolate the engine from the chassis and to align the power-train system of vehicle according to needs. Here we exclusively deal with the failure case of a Heavy duty commercial vehicle Engine Mounts and its optimization. We do formulate a theoretical calculation for the estimation of engine loads, Center of Gravity (C.G) and characteristics of existing engine mount followed by a failure root cause analysis based on design and transmissibility parameters. This is then correlated with data from Computed Aided Engineering and Matlab for analysis of the existing model which is compared to the experimental transmissibility from Road load data Acquisition (RLDA). This is to validate the conditions and propose optimizations to reduce critical failures.

Diesel powered electric generators are used in a variety of applications, such as emergency back-up power, temporary primary power at industrial facilities, etc. As regulatory and customer requirements demand quieter designs, special attention is given to the design of acoustic enclosures to balance the need of noise control with other performance criteria like ventilation and physical protection. In the present work, Statistical Energy Analysis (SEA) approach augmented by experimental inputs is used to carry out Vibro-acoustic analysis of an enclosure for higher capacity Diesel generator set. The exterior sound radiated from an enclosed generator is predicted and further enclosure is optimized for an improved sound-suppression. The airborne sources such as engine, alternator, radiator fan and exhaust are modelled explicitly using experimental noise source characterization. Structure borne inputs are also captured in the test for improving modelling accuracy.

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.

Tractor-semitrailers make up large proportion of heavy commercial vehicles, handling stability of tractor-semitrailers is critical to driving safety. Handling behavior of Tractor-semitrailers is complex and depends on various parameters. This paper presents a mathematical approach & multi body dynamics (MBD) simulation based study to gain an insight as to, how changes to different parameters of the articulated vehicle affect it’s handling behavior and thus to obtain an optimized design in terms of vehicle handling. A Full vehicle multi body dynamic model is created and steady state cornering maneuvers are performed on simulation tool MSC ADAMS/View for calculating understeer gradient using constant radius test method. Various parameters affecting understeer gradient are identified, studied and their relative effect on understeer gradient is measured. These critical parameters were then optimized using MSC ADAMS/View tool to achieve the desired handling targets.

Virtual modeling of engine and predicting the performance and emissions is now becoming an essential step in engine development for off-road application due to the flexibility in tuning of the combustion parameters and requirement of shorter development times. This paper presents an approach where the test bed calibration time is reduced using virtual techniques, such as 1D thermodynamic simulation and 3D CFD combustion simulation for 4 cylinders TCIC engine complying with Stage IIIA emission norms. 1D thermodynamic simulation has played an important role in the early stage development of an engine for selection of engine sub systems like turbocharger, manifolds, EGR system, valve timings etc. The application of 1D Simulation tool for combustion system development, focusing on NOx emissions for an off road multicylinder mechanical injection diesel engine is discussed.

New process development of forging component requires in-depth knowledge and experience related to the process. Also it requires number of physical trials to arrive at optimum process and initial billet dimensions. With the help of reliable computer simulation tool, it is possible to optimize the complete forging process and billet dimensions. Simulation provides much more insight about the process and possible forging defects. This saves considerable time and money. This paper describes about a complete forging process designed for a complex component. With the help of metal forming simulation software, complete forging process was simulated and optimized. Forging defects were removed during optimization of the process. Billet weight optimization was also carried out. Deciding the preforming shape of the billet was the main challenge. An innovative pre-forging shape was arrived which resulted in eliminating one process stage.

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.

An efficient after treatment technique is driven by the need to maintain strict emission norms for heavy-duty and medium-duty ground vehicles. SCR being an advanced active emission technology system for diesel engine, is one of the most cost-effective and fuel-efficient technologies available for complying with the stringent NOx emission legislations. The design of the SCR system involves catalyst selection, complex controller development like urea dosing strategy and the interaction between engine setup and after treatment system. For this purpose, the SCR model must be computationally efficient to evaluate the complete efficiency along with to take care for the NH3 slip also. The SCR model was prepared with respect to SCR inlet temperature and ratio of NOx and ammonia to study the behavior of NOx conversion efficiency keeping consideration of NH3 slip also required for optimizing the calibration.