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In current competitive automobile sector, gear shift quality has become significant factor for vehicle evaluation. OEMs are sensibly focusing on improving gear shift quality to meet customer’s expectations. Though there are different gear shifting habits in different drivers, diagonal shifting is the fastest way of shifting gears in manual transmission vehicle. So the components linked with shift system should be designed to facilitate smooth diagonal gear shift pattern. This paper enlightens the process of defining chamfers on internal gear shifting components for smooth diagonal shifting movement of gear shift lever. It is hard to define chamfers by analytical or practical approach. Creo-mechanism is very useful simulation tool which can be used to understand diagonal shift patterns and to define the chamfers.

The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.

Diesel engines belong to the most efficient power sources for any kind of on-road vehicle, but especially in Europe increasingly for passenger cars. However, more stringent exhaust emission regulations, which will come into force world-wide in industrialised countries during the first decade of the next century will require NOx and particulate emissions to be reduced by up to 60% and more from today's levels. To meet these future emission standards particularly for heavier passenger vehicles, such as SUVs, Pickup Trucks and Light Commercial Vehicles, as well as for heavy luxury class passenger cars, the application of new technologies including advanced exhaust gas aftertreatment systems will be indispensable, especially in view of maintaining the thermal efficiency of diesel engines relative to gasoline engines.

After a review of current and future emission legislation for non-road engines (India, Europe, USA), the various options available to reduce the emissions of diesel tractor engines are discussed. Special emphasis is put on naturally aspirated engines in the 37 - 50 kW power range. AVL has recently designed and developed several naturally aspirated heavy-duty diesel tractor engines to comply with current exhaust emissions standards for the Indian domestic and the US markets (EPA Tier 2). In doing so, different levels of technologies were applied. Their impact on mean effective pressure, specific fuel consumption and emissions will be shown. The future non-road engine exhaust emissions legislation in different markets will be addressed (India, Europe and USA). Compliance with the new emission standards will require the introduction of more advanced technology.

Key on/off Vibrations plays an important role in the quality of NVH on a vehicle. Hence having a good KOKO in the vehicle is desirable by every OEM. The vibration transfer to the vehicle can be refined by either reducing the source vibrations or improving isolation. In this study, critical factors affecting KOKO vibration has been identified. Focus has been given on improving the KOKO by change in mounting system stiffness & stopper gap, and assuming other parameters as constant. The study highlights a new simulation approach using ADAMS View to help run a DOE for solving KOKO issue on vehicle. The contribution of C mount stiffness and stopper gap is shown through simulation results. The correlation between simulation & test results has been established by measuring rigid body modes and KOKO vibration on vehicle for a set of mount configuration. Test results show significant KOKO improvement with the mount configuration optimized through simulation.

If we see from the past and now competition in automotive industry increased tremendously and every car manufacturer are bringing up there innovations into the market and giving a lot of options to the customers to choose and the customer experience as well as satisfaction has become one of the main driver of success for the company. In today’s world of automotive design virtual analysis is playing a crucial role in the design and development. There are software’s that are available in market to simulate practical conditions digitally. Here we are mainly focused on effect of change in engine mount stiffness on acceleration at driver seat rail point using ADAMS. Which facilitates reduction of design of experiments and finalizing optimized stiffness values for engine mounts for engine idle vibration refinement point of view. ADAMS is mechanical system analysis software where we can simulate the dynamic behavior and distribution of loads throughout the system.

Basic Function: Vehicle remote is used for vehicle lock/unlock/search/Hazard lights /approach light functions for customer convenience and vehicle security system. Conventional approach: 1 Use of separate RF (Radio Frequency) receiver -Additional Cost impact. 2 High remote RF power - Reduced remote battery life and bigger remote size required 3 High sensitivity RF receiver - High cost. Low Cost approach: It involves the followings: 1 Integration of RF receiver inside the Body Control Module (BCM). 2 Low Power Remote and Optimization of Remote PCB layout to get the maximum power. 3 External wired antenna taken out from BCM and proper routine need be ensured to get the best performance. 4 BCM mounting location to get the best remote range in all vehicle directions. This paper relates to the methodology for low cost approach for the RF communication between remote transmitter and receiver with achieving the best remote performance at vehicle level condition.

The usage of forging a preformed, near net shape, compacted and sintered metal powder has been widely accepted since the eighties and is now one of the mainstays for producing Connecting rods in North America. However, its use in Indian subcontinent is limited as its counterpart i.e. conventional steel forging is still the most dominant. Powder metallurgy route has many advantages like good dimensional accuracy; minimum scattering of weight etc. Despite these advantages, the Powder metallurgy process is still not preferred predominantly due to technical (endurance) and infrastructural limitations. This work envisages combining the benefits of powder metallurgy process with the required mechanical properties viz. tensile and fatigue strength alongside design modifications to meet the requirements of a connecting rod for a 2-cylinder diesel engine. The connecting rods met the fatigue life at the required FOS equaling the performance of a conventionally forged connecting rod.

Breather assembly is mounted on transmission to maintain the pressure equilibrium inside transmission. Breather allows the transmission to breathe air when the air inside transmission expands or contracts due to heating and cooling of lubricating oil during vehicle running. Breather allows the hot air to escape and cool air to enter into the transmission to prevent overheating issue. Failure of breather assembly can lead to pressure buildup inside transmission and further leading to leakage from transmission oil seals. Oil leakage through the breather assembly is governed by parameters such as opening pressure, location and orientation of breather etc. The transmission undergoes different operating conditions of input speed, load, temperature, inclination etc. Also, breather assembly is designed and positioned in such a way that there is no leakage through breather due to oil splash inside the transmission.

Brake system is the most important system in the vehicle considering the overall vehicle safety and speed control. Brake applications are repetitive during a city traffic and hilly terrain on downhill gradient. Frequent braking gives rise to an overheating of the brake drum and its components. Braking operations at high temperature gives rise to problems like reduced deceleration due to loss of brake pad friction characteristics, pad softening and sticking to drum, pad distortion and wear etc. All these factors collectively result in deterioration of the braking performance and reduction of brake pad durability with time. Till date most of the thermal analysis performed for brake drum heating are through physical testing using brake system prototypes and by means of CFD tools. These methods are time consuming and expensive. There is a need for an alternative method to reduce physical trials and prototype building and reduce dependency on CFD analysis.

The paper reports on a study performed as a joint project between Rhodia, Renault Automobiles and AVL and deals with the application of a sintered metal trap (SMT) whose regeneration is supported by the use of a Ce-based fuel-borne catalyst installed on a delivery van equipped with a conventional IDI/NA diesel engine. For demonstration purpose, a trap protection strategy was developed with the aim to minimize the trap loading and thus the consequent fuel consumption penalty that can be observed for worst-case low speed driving scenarios. Measures to temporarily increase the exhaust gas temperature during inner-city driving and therefore to initiate the start of regeneration were successfully applied. MAJOR EFFORT IS BEING currently undertaken to develop and apply advanced aftertreatment systems to meet future proposed exhaust gas emission standards for passenger cars, LDT and HD diesel engines.

In today’s manual transmissions of car, gearshift system requires high performance with particular emphasis on low effort, minimal travel and positive feel. To meet these targets, a high capacity multi cone synchronizers along with higher co-efficient of friction material used for lower gears. The design of synchronizer with these specifications is influenced by torsional fluctuations from engine. Excessive torsional vibrations leads to wobbling of synchro rings within the peripheral clearances with surrounding parts. Wobbling leads to abrasion wear of frictional area of synchro ring causing grating or crashing noise of gears during shifting. This paper presents the optimization of the multiple cone synchronizer design exposed to excessive torsional vibrations and validation of the same on test bench during development stage instead vehicle level validation.

The engine compartment of passenger car application contains various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the body temperature of individual component. The rise in body temperature of critical components can endanger the durability or functionality of the specific component or a system in which it operates. The aim of this paper is to strategize thermal protection of the rear mounted engine and its components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECUs, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan.

The prosperity of modern society is unthinkable without technology. One of the most important technical products so far is undoubtedly the automobile. It has been used by man to satisfy his deeprooted desire for freedom, independence and mobility. 500 million motor vehicles on the roads across the world are clear evidence of the fact that society no longer wants to forego the benefit of the automobile. According to the forecasts of several experts, the car population may reach 1.3 billion by the middle of the next century - if the markets keep developing as expected. This enormous growth rate places an obligation on engineers in the automobile industry to do everything to further improve the automobile. Above all, this demands an additional deduction of fuel consumption as well as efforts to keep negative impact on the environment to a minimum. Modern high speed direct injection diesel engines distinguish themselves from other internal combustion engines through their high efficiency.

Engine mounting system maintains the position of powertrain in the vehicle with respect to chassis and other accessories during inertia, torque reaction loads and roadway disturbances. The mounting system also plays a role in terms of isolation of the rest of the vehicle and its occupants from powertrain and helps in maintaining vehicle ride and handling condition. This paper investigates the performance comparison between hydromount and switchable hydromount during idle and ride performance. The optimization scheme aims to improve the performance of the mounting system in order to achieve overall powertrain performance and NVH attribute balancing through switchable mount technology.

In case of new generation of commercial vehicles, three shaft transmissions are designed with press fitted gears on counter shaft. It allows user to save the cost of transmission manufacturing by considerable amount. In case of heavy commercial vehicles, which are being used in abusive conditions such as mining and off-road applications, it becomes absolutely necessary to ensure that the gears press fit should withstand the continuous loads and impact loads. There are design guidelines available to ensure proper fit and torque carrying capacity between the mating parts. Still, there are gear slippage, shaft and gear breakage failures in the field. In this scenario, there is a need to develop bench test procedure which will capture such failures in the prototype stage. Looking at the failures in the field, it is necessary to capture all above hidden failures in design validation phase.

NVH refinement of passenger vehicle is very much essential to level that customer did not find any irritation. Engine mounting selection and design is critical to achieve targeted NVH performance. Most of OEM’s are using properly tuned hydromount to have best idling NVH performance. Hydro-mount design should be tuned at problematic frequency where we can get the very low dynamic stiffness and can get the required performance. Hydromount should be designed carefully otherwise there will be abnormal noise due to cavitation effect. Cavitation noise is such a noise which is very difficult to identify that it is coming from mount. Cavitation is the formation and collapse of vapor bubbles in a working fluid when local static pressure falls below the vapor pressure of the working fluid. Systematic approach is presented in this paper to detect cavitation noise from hydraulic mount and how to overcome the same.

Tailgate stoppers play vital role in exerting preload on the Tailgate latch mechanism and also restrict the relative motion of the Tailgate against vehicle Body in White (BIW). These stoppers act as over-slam dampeners and reduce the transmissibility of vibrations thereby reduce the risk of Squeaks & Rattles (S&R) noises. S&R noises from Tailgate are most annoying to the rear passengers in the vehicle and are recurring in nature. Preventing these issues during design is a challenging task. S&R risk simulations enable us to conduct virtual Design of Experiments (DOEs) and arrive at optimal solutions. This approach helps in reducing the cost of the design changes that are required in the physical prototype at the later stages of product development and save time. The risk evaluation in the simulations is based on the relative displacement at the interfaces of two components.

The changing mobility landscape of India reveals that the erstwhile transport modes of the 20th century i.e., railways and road buses are making way for airlines, personal vehicles, shared mobility, metro rails. Rapid technological changes, stricter regulations, new transport cultures autonomous, connected, electric and shared (ACES), state-of-the-art and environmental concerns are shaping up the eco-system for automobiles. Despite these challenges roadways and automobiles will continue to be most prominent solution in India for future. But for that, the automobile sector should be agile, innovative, and adaptable to changing eco-system, vigilant to thwart threat of alternate mobility solutions and must provide sustainable solutions for the future. The purpose of this paper to evaluate various mobility solutions, ascertain prominence of upcoming automobile solutions and their sustainability for future in India.

Electric motor mounts resonate at high frequency in the range of 600 to 1000Hz with motor excitation frequency resulting in isolation performance deterioration. There is a selection process of motor mounts such that the force-transfer under transient torque reduced and also avoids high-frequency resonance. The rubber dynamic stiffness plays a significant role in excitation frequency. Rubber shape factor and compound directly contribute towards the dynamic stiffness properties of the mount. Isolation efficiency depends on force transfer to the body and resonance phenomenon. In this paper, the rubber shape of motor mounts, which affect progression characteristics as well as high-frequency resonance, is discussed. The wings-effect of rubber bushes discussed which can be tuned to get the desired frequency shift in order to avoid resonance.