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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.

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.

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.

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).

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.