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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.

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.

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.

‘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 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.

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).

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 a methodology for design and development of On-Board Diagnostic system (OBD) with an objective to improve current reliability process in order to ensure design & quality of the new system as per requirement of commercial vehicle technology. OBD is a system that detects failures which adversely affect emissions and illuminates a MIL (Malfunction Indicator Lamp) to inform the driver of a fault which may lead to increase in emissions. OBD provides standard and unrestricted access for diagnosis and repair. Below given Figure 1 shows the working principle of OBD system. The exhaust emission of a vehicle will be controlled primarily by Engine Control Unit (ECU) and Exhaust Gas After Treatment Control (EGAS CU). These two control units determine the combined operating strategies of the engine and after treatment device. Figure 1 Modern Control Architecture for OBD System in Commercial vehicle [1]

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.

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.