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With the enforcement of ever stringent emission norms, vehicular subsystems are witnessing a substantial transition from electro-mechanical to electronic control-based systems. With the inclusion of incremental modifications to be suitable for future applications, the electrical system has reached a point where it is undergoing a major transition. Further catalyzing this reform is the demand for mass passenger safety, bringing about its own set of uncompromising norms. While the implications of the regulations enforce cleaner and safer mobility, there also arises a conflict between vehicular functionality and safety. This paper enumerates on the first-hand experience of how the direct transfer of the elementary vehicle battery isolator from the prior euro-4 electrical system to the present euro-6 system resulted in a disharmonized vehicle operation when made to comply with both functionality and passenger safety norms.

Engine mounts are an integral part of the vehicle that helps in reducing the vibrations generated from the engine. Engine mounts require a simple yet complicated amalgamation of two very different materials, steel and rubber. Proper adhesion between the two is required to prevent any part failure. Therefore, it becomes important that a comprehensive study is done to understand the mating phenomenon of both. A good linking between rubber and metal substrate is governed by surface pretreatment. Various methodologies such as mechanical and chemical are adopted for the same. This paper aims to present a comparative study as to which surface pretreatment has an edge over other techniques in terms of separation force required to break the bonding between the two parts. The study also presents a cost comparison between the techniques so that the best possible technique can be put to use in the commercial vehicle industry.

In the view of an eco-friendly environmental future, the major automotive manufacturers are making a move towards electric mobility. The electric vehicle helps to achieve Zero-emission. However, there are some limitations too. The zero-emission Battery electric vehicle (BEV) can provide a limited range only; the market penetration is getting difficult because of an energy storage capability. The addition of an electric vehicle with a fuel cell unit and a hydrogen supply unit can increase the range and the energy capacity of the system. Fuel cell electric vehicle (FCEV) system is faster to refill compared to plug-in Battery electric vehicle (BEV). This study deals with a behavioral analysis of Polymer Electrolyte Membrane (PEM) Fuel cell; with different drive cycles. In this, a fuel cell model developed and simulated in the SIMULINK environment with different drive cycle and results were obtained. The fuel cell controls also were analyzed for the city start/stop cycle.

In the current commercial vehicles market, ride-comfort and handling are crucial parameters for the customer and end user. There are various aspects which determine the vehicle behavior. One of aspects is the structural rigidity of the vehicle, which has its own effect on vehicle dynamics. To meet the required stiffness of the main structural component of the vehicle i.e. chassis frame, FEA analysis has to be done in current methodology. The number of iterations have to be done to build an appropriate model with low weight, which can meet the design requirements. At first, conceptual design mock-up unit is to be developed then FEA (CAE) analysis to be done on it. If any design criteria are not met, then this cycle repeats again until it fulfils the required stiffness. Today, the direct stiffness procedure is the basic principle of almost every FEA software package.

Turbocharging has become an important method for increasing the power output of diesel engines. A perfectly matched turbocharger can increase the engine efficiency and decrease the BSFC. For turbocharger matching, engine manufacturers are dependent on the turbocharger manufacturers. In this paper, an analytical model is presented which could help engine manufacturers to analyze the performance of turbocharger for different load and ambient condition using compressor and turbine map provided by turbo manufacturers. The analytical model calculates the required pressure at inlet and exhaust manifold for fixed vane turbocharger with waste gate using inputs like BSFC, lambda, volumetric efficiency, turbocharger efficiency and heat loss, that are available with the engine manufacturer.

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.

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.

Ever-increasing operational cost, reducing profit margins & increase in competition, it is of upmost significance for fleet owners & drivers to opt for a vehicle having maximum uptime. OEM's are under immense pressure to design & develop vehicles/subsystems which are reliable enough to minimize downtime & withstand heavy overloading plus extreme operating conditions especially tippers. Vehicle systems like Wheel end (hub, bearing, and grease) which are designed & packaged according to a very stringent envelop & operate as a closed system facing all the extremities of operating conditions. This undoubtly make them prone to no. of failure modes which are resulting in vehicle unplanned stoppages, so any failure mode related to the same must be taken care with utmost importance. In commercial vehicles the bearing outer cup is in interference fit with the hub. These bearings of wheel hub have to be maintained at the wheel end play of few microns.

The need to develop products faster and to have designs which are first time right have put enormous pressure on the product development timelines, thus making computer aided optimization one of the most important tool in achieving these targets. In this paper, a design of experiments (DOE) study is used, to gain an insight as to, how changes to different parameters of front suspension and steering of a passenger bus affect its kinematic properties and thus to obtain an optimized design in terms of handling parameters such as bump steer, percent ackermann error and lock to lock rotation angle of steering wheel. The conventional hit and trial method is time consuming and monotonous and still is an approximate method, whereas in design of experiments (DOE), a model is repeatedly run through simulations in a single setup, for various combinations of parameter settings.