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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.

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]

In mining tippers, rear suspension plays a major role in defining vehicles ride and handling characteristics, stability and load carrying capacity. Bogie type of suspension is well suited for these applications. Bogie suspension mainly consists of bogie bracket, leaf springs and radius rods. Nonlinear static analysis is performed for a bogie bracket assembly considering bolt pretension and contacts to evaluate the static strength of bogie bracket. Since bogie bracket is connected to frame with several bolts, a sensitivity analysis is carried out to study the effect of bolt loosing on bogie bracket. The surface contact interaction (stick-slip) behavior between frame and bogie suspension mounting bracket is also studied. Good correlation is achieved with testing results.

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.

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.

The aerodynamic drag of cars, trucks and buses have been closely examined over the years. Many of them focus on the front end and to some extent on rear end of the vehicles [1]. Of course these are the two surfaces that contribute to more than 85 % of the total drag. This is because these surfaces are almost normal to the direction of air flow and hence create enormous pressure differences and hence drag. A lot of optimization has also gone into these, by way of reducing the sharp corners at ‘A’ pillars, introducing aerodynamic dome and even ‘boat tail flap plates’ [2-3] for some trailers. However, part of the vehicle that has not received sufficient attention in aerodynamic drag considerations is the ‘transverse outer profile’ of vehicle. This transverse outer profile is nothing but the cross sectional profile formed by the vehicle's sides, roof and their integration.

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.

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.