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Fuel efficiency is critical aspect for commercial vehicles as fuel is major part of operational costs. To complicate scenario further, fuel efficiency testing, unlike in passenger cars is more time consuming and laborious. Thus, to save on development cost and save time in actual testing, simulations plays crucial role. Typically, actual vehicle speed and gear usage is captured using reference vehicle in desired route and used it for simulation of target vehicle. Limitation to this approach is captured duty cycle is specific to powertrain and driver behavior of reference vehicle. Any change in powertrain or vehicle resistance or driver of target vehicle will alter duty cycle and hence duty cycle of reference vehicle is no more valid for simulation assessment. This paper demonstrates approach which uses combination of tools to address this challenge. Simulation approach proposed here have three parts.

Nowadays, tractors are frequently used with front-end loaders, dozers and backhoes to cater to various non-agricultural and construction application needs. These applications require frequent shifting of gears due to the constant need for a tractor's forward/reverse direction of motion. Hence, the tractors are fitted with a power shuttle transmission (PST) to cater this need. Power-shuttle transmission (PST) development is a design process that incorporates multiple disciplines such as mechanical, hydraulics, controls and electronics. This paper presents a simulation-based approach to model the power shuttle transmission of the tractor. Firstly, individual components of PST are modelled in detail and then integrated with the complete tractor model. For this, GT-Suite has been used as a simulation platform.

Manual transmissions are characterized by gear ratios that are selectable by locking selected gear pairs to the output shaft inside the transmission. Top gear is selected to get a maximum speed and is limited by the engine power, speed and the fuel economy. Lower gears are selected to get maximum speed at maximum gradient. Lower gears are also expected to give creeping speed to avoid usage of clutch and brake in city traffic. Selection of intermediate gears is such that it provides a smoother gear shift. Gear spacing is done in geometric progression. Spacing between the higher gears is usually closer than in the lower gears because drivers shift more often between the lower gears. This is opposed to the conventional idea of progressive spacing where higher gears had more space between them. An objective method is provided for selecting gear ratios for use in vehicle transmission having multiple selectable gears.

Rear axles are subjected to bending and torsion loads out of which Bending loads are predominant. In case of Off road vehicles Bi Axial- combination of Bending and torsion loads were predominant, because of axle construction and vehicle usage pattern. Defined test procedures are available for bending durability and torsional durability evaluation of axles. In this experiment, new test methodology was developed for Bi Axial durability evaluation of Off road vehicle rear axle with single servo hydraulic linear actuator. For creating Bi Axial load condition, we may need multiple actuators and complicated fixtures. Axle wheel end is constrained at an angle with suitable fixtures for creating the bending and torsional forces together in the axle. Servo hydraulic linear actuator with suitable loading arm is used for applying the test torque in the axle input flange.

Differential in Gear Box play vital role in Tractors for assisting it in turning and also to take straight path. Light weight machine always have advantage in terms of fuel economy and performance. Weight optimized rotating part have additional benefits of saving power loss, against stationary dead weight. Differential Housing is such a part, which rotates during the vehicle motion and torque transmission. [1] This paper describes a method by which weight of the Differential Housing is optimized. In this particular body of work, additional constraints of avoiding any change in existing cold forged parts like Bevel Gear & Pinion. This also have additional benefit of enhanced flow of Oil inside Differential Housing for better lubrication of Bevel Gears and Pinion. This resulted in weight saving of Differential Housing and finally fuel economy of Tractor.

Overall in-vehicle visibility is considered as a key safety parameter essentially mandated due to the increasing traffic scenario as seen in developing countries. Driver side bottom corner visibility is one such parameter primarily defined by A-pillar bottom and outside rear-view mirror (OSRVM). While defining the OSRVM package requirements such as size, position and regulatory aspects, it is also vital to consider other influencing parameters such as position of pillars, waist-line height, and Instrument panel which affect the in-vehicle visibility. This study explains the various package considerations, methods to optimize OSRVM position, shape and housing design in order to maximize the in-vehicle visibility considering the road and traffic conditions. A detailed study on in-vehicle visibility impacted by OSRVM packaging explained and had been verified for the results.

This paper focuses on optimizing the electrical energy consumption of vehicle. By introduction three concepts. 1) Innovative speed control logic for radiator fan motor according to vehicle speed and air flow through radiator. 2) Introducing regeneration of energy from radiator fan motor while free running and deceleration of vehicle. 3) Using BLDC motors (generation mode and motoring mode) in radiator and blower motors. About 50 % of total electrical energy consumption of vehicle is contributed by radiator fan motor and blower motor (proven data by performing alternator charge balance test during NEDC cycle). By introducing above three concepts, 50 % electrical energy consumption can be reduced to 25 - 30 %, which gives more than 3.5 % fuel economy improvement and more than 10 gmCO2 reduction per kilometer. Further reduction in conducted emission at motor level, soft starting for radiator fan and blower motor and elimination of high inrush current.

Several studies in the field of hedonics using subjective responses to gauge the nature and influence of odors have attempted to explain the complex psychological and chemical processes. Work on the effect of odors in alleviating driver fatigue is limited. The potential to improve road safety through non-pharmacological means such as stimulating odors is the impetus behind this paper. This is especially relevant in developing countries today with burgeoning economies such as India. Longer road trips by commercial transport vehicles with increasingly fatigued drivers and risk of accidents are being fuelled by distant producer - consumer connections. This work describes a two stage comparative study on the effects of different odors typically obtainable in India. The stages involve administration of odorants orthonsally and retronasally after the onset of circadian fatigue in test subjects. This is followed by a small cognitive exercise to evaluate hand-eye coordination.