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In today’s world, due to fast depletion of fossil fuel and the increasing CO2 emission, the need to switch to alternate energy sources are higher. Stringent norms on exhaust emissions in IC Engine vehicles implies, very complex after treatment systems. Already many OEMs have refined their development strategies towards phasing out of IC Engines and bringing in Fuel Cell vehicles, Battery Electric Vehicles and Hydrogen IC Engine vehicles. Focus is on Hydrogen for Long Haul vehicles. In this paper cooling system design is demonstrated for Fuel Cell, Battery and Power Electronics system in a Heavy Duty Fuel Cell Electric Truck. Radiator and Fans are selected based on the overall heat rejection and Coolant inlet temperature requirements of components. Cooling system circuit and pump is decided to meet the coolant flow rate targets. High temperature cooling system and Low temperature cooling system are explained in detail. Thermal simulation is done using simulation software KULI.

Due to recent infrastructural development and emerging competitive automotive markets, there is seen a huge shift in customer’s demand and vehicle drivability pattern in commercial vehicle industry. Now apart from ensuring better vehicle durability and best in class tyre life and fuel mileage, a vehicle manufacturer also has to focus on other key attributes like driver’s safety and ride comfort. Thus, for ensuring enhanced drivability, key parameters for ensuring better vehicle handling includes optimization of bump steer and brake steer. Both bump steer and brake steer are vehicle’s undesirable phenomenon where a driver is forced to constantly make steering wheel correction in order to safely maneuver the vehicle in the desired path.

The Chassis Dynamo-meter system provides a means of testing vehicle in place of driving them on the test track or highway. The machine simulates road conditions in speed, torque or road load control modes, allowing the vehicle to experience the same forces as it would be on the test track or highway. Chassis dynamo-meter with its 24 x 7 capabilities can perform several value-added tests to assess vehicle performance while operating under load in short period of time and with other intangible benefits such as well-timed product launch, reduced breakdown time and faster failure resolution, Dynamo-meter is worthy of an investment. However, the scale of investment and constraints in required infrastructure limits the number of dynamo-meters in a R&D center of Original Equipment Manufacturers.

Design decisions based on the virtual simulations leads to reduced number of prototype testing. Demonstrated correlation between the computer simulations and experimental test results is vital for designers to confidently take simulation driven design decisions. For the virtual design evaluation of durability, ride, handling and NVH performance, demonstration of correlation of structural dynamic characteristics is critical. Modal correlation between CAE and physical testing validates the stiffness and mass distribution used in the FE model by correlating mode shape and mode frequency in the desired frequency range. The objective of this study is to arrive at a method for establishing modal correlation between CAE and experimental test for a bare frame and thereby enabling evaluation of design iterations in virtual environment to achieve modal targets.

In today’s commercial vehicle scenario, designing and developing a component which will never fail throughout its lifespan is next to impossible. For a long time especially in the field of automotive, any crack initiation shall deem the component as failed and the design requires further modification. This paper deals with studying the failure of one such component and understanding the effect the crack has on the overall life of the component i.e. understanding the remnant life of the component. The component under study was gear shift lever bracket and is mounted on the engine exhaust manifold. It experiences two types of loads: inertial load due to the engine vibration and gear shift load. Frequent failures were observed in the field and in order to simulate it at lab, an accelerated test approach was adopted. The engine operating speed was used to identify the possible excitation frequency which the component might experience.

The commercial vehicle industry is evolving faster with the rise in multifarious aspects deciding a company's progress. In the current scenario, vehicle performance and its reliability in the areas of payload, fuel economy, etc. play vital roles in determining its sustenance in the industry, in addition to reducing driver fatigue and improving comfort levels. Test quality and time is the key to assure and affirm, smooth and quick launch of the product into the market. This paper details on the design of Multi-Axis road data simulator which entails realistic loads onto the components for capturing meaningful information on behavior of the product and recreate the field failure modes. The design was conceptualized keeping in mind both cost (for initial installation and running cost) and time for testing without loss in the convergence factor.

This paper describes the system architecture together with control and diagnostics features of an indigenously developed electric vehicle controller for Light Commercial Vehicle. The key functions of vehicle controller include power management, driveline controls, regeneration and vehicle mode controls. In particular this paper presents vehicle's operational strategy in economy, normal and performance modes based on the vehicle speed and SOC. It also has feature to enable vehicle operation in reduced performance mode at low battery voltages. The battery fault predictor algorithm is also described in detail that is used to control discharge current to prevent sudden dip in SOC and to increase battery life. The vehicle control strategy is modeled & simulated using MATLAB™ environment and results for a specific test case are validated with embedded controllers-in-the-loop in a test-bench environment.

Diesel engines are primarily being used for Power Generation due to its higher thermal efficiency and its superior fuel consumption compared to gasoline engines. Due to the growing awareness of environment protection and producing eco-friendly products, government agencies throughout the world have started introducing legislations which would limit the emissions produced by engines and would help in resolving the cause for cleaner and greener environment. In similar lines, Central Pollution Control Board (CPCB) has proposed to introduce the next stage of stringent emission norms for engines used in Power Generation by April 2014 which are comparable to the best in the world. This paper deals with the strategies applied and experimental results for meeting the proposed CPCB-II norms.

Vehicle light-weighting of late has gained a lot of importance across the automotive industry. With the developed nations like the U.S. setting stringent fuel economy targets of 54.5 mpg by 2025, the car industry's R&D is taking light weighting to a whole new level, besides improving engine efficiency. The commercial vehicles on the other hand are also gradually catching up when it comes to using alternate material for weight reduction. This paper will discuss light-weighting in the context of buses though. For a typical bus, the contribution of shell structure weight in the bus body weight is more than 40%. This qualifies as the area with a huge potential for weight saving. On the other hand the shell structure forms the base skeleton of the bus body providing it with adequate strength and stiffness for meeting both functional (bending & torsional stiffness) and passive safety requirements (rollover compliance).

Bus and coach drivers spend considerably more time in the vehicle, compared to an average personal car user. However, when it comes to comfort levels, the personal cars, even the inexpensive hatchbacks score much higher than a standard bus. This is because the amount of ergonomic design considerations that go into designing a car's DWS (driver workspace) is much more than that of buses. To understand this lacuna, the existing standards and recommendations pertaining directly or remotely to bus driver workspace were studied. It was understood, beyond certain elementary recommendations, there were very few standards available exclusively for buses. This paper ventures to establish a set of guidelines, exclusively for designing bus and coach driver workspace. The various systems in the driver's work space and their relevance to driver's ergonomics are discussed. References are drawn from different case studies and standards to come up with recommendations and guidelines.

‘To achieve more from less’ has been the oft-quoted phrase in auto industry for quite some time. This philosophy has many analogies like fuel efficiency, modularity, weight reduction, alternative fuels etc. Of these ‘modularity’ is seen as an effective tool, especially for automotive OEMs catering to a wide portfolio of similar products. This paper discusses the implications of modularization on a passenger bus OEM, by taking the ‘bus super structure’ as a test case. The modularized bus structure is compared with the conventional structure for design strength, safety, weight and more importantly manufacturing flexibility. The challenges faced in each of these aspects are discussed. From the study it was understood that the task of manufacturing body modules and interfaces is complex and it calls for a complete revamp of existing fixtures, material handling equipment and even the prescribed tolerances.

The crankshaft twist is of great concern for heavy duty engines. In order to have a longer B10 life and better NVH characteristics, it is desired to have minimum Torsional vibrations (TV) in the crank shaft. To keep the crankshaft twist in check - TV dampers are used. Aneasier approach is to use a Viscous TV damper which keeps TV below acceptable limit for entire speed range. But this is a very costly approach. In this paper, the design of rubber TV damper for multi-cylinder engine was optimized to have lower TV characteristics. The optimized rubber damper has been developed with AEM - VAMAC™ grade rubber. This material provides advantages of better TV attenuation, higher thermal resistance, oil resistance higher durability and a much longer life than other rubber compositions. Besides rubber profile was also optimized to obtain higher slip torque. The TV amplitudes with existing rubber compound (EPDM -Ethylene Propylene Diene Monomer) were measured in the engine testbed.

India has the highest number of road accidents in the world. With over 130,000 deaths annually, the country has overtaken China and now has the worst road traffic accident rate worldwide. This has been revealed by the World Health Organization (WHO) in its Global Status Report on Road Safety pointing to speeding as the main contributing factor. This paper studies and details all the approaches for the reduction of accidents adopted by various countries and especially the necessity of speed governors in Indian vehicles and the role of the same in reduction in accidents with other benefits of speed governors with regard to fuel efficiency, noise & pollutant emissions both in Indian and International aspects. [Reference 7]

Natural gas (CNG) vehicles have been introduced in many parts of world including India, Europe and United States and achieved tremendous success in addressing the energy security and pollution challenges. This paper describes in detail the safety requirements for CNG vehicles in India, Europe and United States. Various safety and design requirements for CNG fuel system components such as gas cylinders, cylinder valves, fuel lines, filling connection, pressure regulator, gas-air mixer, electrical systems, are explained. The safety requirements described in ISO standards, UN-ECE standards, USA FMVSS, NFPA standards and Indian Standards are compared and discussed in detail. It also specifies the procedure for commissioning and installation of CNG vehicles. Further, it is concluded that all these international standards for CNG vehicles have adequate provisions with regard to impact protection, passenger safety and fire safety.

Overloading is not only a problem for larger goods vehicles, it is equally a problem for smaller vehicles, such as vans, cars and passenger carrying vehicles. Reports indicate that nearly 70% of all traffic on national highways comprise of cargo vehicles while 22% of cargo vehicles are involved in road accidents. Overloading increases the risk of traffic accidents and causes excessive wear and damage to roads, bridges, pavements etc. This paper specifies in detail the existing Indian Legislation on Overloading, different methods of monitoring, Vehicle Overload Control in other countries and India recommendations to curb Overloading of vehicles.

Buses have been main means of mass transport in organized as well as unorganized sectors in India. Though the art and science of Chassis Designing had been practiced and matured by all Indian OEMs, Body design had long not been accorded high priority by them. Till 1989, there was no comprehensive set of rules enforced. Bus designs were developed with scant regard for safety and emission. OEMs sold their products in the form of drive away chassis and the Body Design & Body Building was largely left to Body Builders, many of whom employed poor design, build and quality control practices. Spurious materials, parts, non-uniform construction resulted in number of accidents and many of them were fatal. Central Motor Vehicle Rules (CMVR) kicked-in 1st July 1989. With roll out of CMVR, various safety related features like entry/exit door, emergency exits, window frames, their locations, dimensions and designs were defined.

There have always been different approaches when it comes to ‘Bus body architecture’. The design approach has gone through different phases namely, chassis based, semi integral, integral and monocoque. Equally varied is the choice of material for bus super structure. The predominantly used ones are - mild steel with galvanization, stainless steel (SS) and aluminum. This paper discusses the rationale behind choosing stainless steel for the complete bus structure. With rapid development in infrastructure and public mass transit system, it has become imperative to have a robust structure for buses that is durable and crash worthy. Among the family of stainless steels, ferritic stainless steel exhibits excellent mechanical properties with corrosion resistance and better strength to weight ratio compared to the galvanized mild steel.