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Manual transmission (MT) is still the most preferred solution for emerging markets due to the lower cost of ownership and maintenance coupled with a higher transmission efficiency. In this regard, continuous improvement of the transmission shift quality is quite essential to meet the growing customer expectations. In the present work, a detailed evaluation of the gear-shift impulse (experienced at the gear-shift knob) is conducted between two different architectures of a manual, high-torque (450 Nm input torque) inline transmission meant for a sports utility vehicle (SUV). The conventional manual inline transmission architecture comprises a common gear pair at the input of the transmission. While this input reduction architecture is the most widely used architecture, having the common gear pair at the output of the transmission is also another option. The synchronizers of the manual transmission need to match the speed of the rotating components just before the gear-shifting event.

In automotive manual transmission gearboxes, the synchronizer rings play a vital role in gear shift operations. The efficiency of the synchronizer ring depends upon the frictional surface geometry. The critical parameter is the synchronizer ring frictional surface circularity. The circularity deviation causes higher synchronizer ring wear and poor cone torque generation. With the current manufacturing methods and the thickness of the synchronizer ring, circularity improvement is a challenge. The synchronizer ring thread turned part is lapped to improve the circularity. Reduction in circularity can be improved by optimizing the lapping operation. In this work, an optimal lapping condition was developed using statistical methods. Taguchi DOE was used to analyze the different parameter combinations along with the noise parameter – different ranges of circularity variation in turning operation. This helps to find the best lapping parameter settings to improve the reduction in circularity.

Manual transmissions are the preferred transmission for drivers who love sporty gear shifts. Manual transmission vehicles are cheaper, very efficient, and offer quick gear shifts. Worldwide manual transmission contributes to 36.15% and in India it contributes overall 80% of today's market share. The customers expect a very smooth gearshift which is a challenge to achieve in all ambient temperatures. In a gear shift event, the synchronizers synchronize the speed of the gears. The force applied at the gear shift knob, generates the cone torque and stops the rotating input shaft for the Neutral (N) to 1 gear shifting. The early morning gear shifts have high gear shift effort. This effort is getting reduced with the increase in temperature. This is due to the drag in the gearbox which is inevitable. This work focuses on improving the very first gear shift event of N to 1 after the engine crank from cold (8°) to hot (80°) condition.

Attaining better acoustic performance and back-pressure is a continuous research area in the design and development of passenger vehicle exhaust system. Design parameters such as tail pipe, resonator, internal pipes and baffles, muffler dimensions, number of flow reversals, perforated holes size and number etc. govern the muffler design. However, the analysis on the flow directivity from tail pipe is limited. A case study is demonstrated in this work on the development of automotive muffler with due consideration of back pressure and flow directivity from tail pipe. CFD methodology is engaged to evaluate the back pressure of different muffler configurations. The experimental and numerical results of backpressure have been validated. The numerical results are in close agreement with experimental results.

In an off-road vehicle, Vehicle Structure plays a major role in passenger safety, Aesthetics, Durability, through a validated construction of canopy structure. This structure is to maintain the shape of the vehicle and to support various loads acting on the vehicle. In present market a safe, Durable, Robust, Waterproof, Noise less, Light weight and cost-effective off-road vehicle will always be a delight for any customer. However, the current conventional way of Soft top vehicle structure use metal brackets and formed sheet parts to create a structure to retain the canopy shape in place. These conventional structures are often heavier and would have many demerits such as heavy weight, Corrosion, Risk of canopy tear due to metallic structure edges and inappropriate draining, water management. Considering this we replaced the heavy metal brackets in to blow molded plastic parts.

Bolted joints are the most used joints in automotive suspension assemblies. They are expected to retain the strength over the course of useful life of the vehicle and contribute to durability in a big way through reduction of stress amplitudes. Any sort of loosening or slip or breakage in these joints can lead to noise or catastrophic failures. In the past, such issues were addressed through thumb rules and design guidelines. However, with the focus on first-time right tests with reduced validation time it has become important to upfront predict the suspension joint integrity through simulation. Toward this objective, a novel approach was developed to simulate the suspension joint integrity for bolted joints. This approach considers various parameters like bolt preload, tolerance stackup of the parts in the joint, coefficients of friction of various interfaces, quality of contact and effect of deformation at the thread interface on joint integrity.

Plastics are prone to photo oxidative and thermal oxidative degradation under usage conditions due to their chemical nature. From sustainability and cost standpoint, there is an increasing focus on Mold-In-Color (MIC) plastic materials. Simultaneously customer’s expectations on the perceived quality of these MIC parts has been increasing with attractive color and glossy appearance. A study was conducted to analyze the product quality and durability aspects over a prolonged exposure to accelerated weathering condition. Material selected for this study were injection molded specimens of ABS and PC-ABS used in automotive passenger vehicles. Comparative analysis was conducted before and after weathering exposure at defined intervals by using Fourier Transform infra-red spectrometer (FTIR), differential scanning colorimetry (DSC), universal testing machine (UTM), Izod impact tester and microscope to understand the impact on their chemical and mechanical properties.

Objective metrics for performance evaluation of ride, handling and steering are required to compare, validate and optimize dynamic behavior of vehicles. Some of these objective metrics are recommended and defined by International Organization for Standardization (ISO) and Society of Automotive Engineers (SAE), which involve data processing, statistical analysis and complex mathematical operations on acquired data through simulation or experimental testing. Due to the complexity of operations and volume of data, evaluation is often time consuming and tedious. Process automation using existing tools such as MS Excel, nCode, Siemens LMS, etc. includes several limitations and challenges, which make it cumbersome to implement. This work is about development of a centralized platform for quantification, visualization and comparison of ride, handling and steering performance metrics obtained from testing and simulation data as per relevant ISO standards.

Toe setting is one of the major wheel alignment parameters which directly effects handling of a vehicle. Correct toe setting ensures desired dynamic behavior of an automobile like straight line stability, cornering behavior, handling and tire durability. Incorrect setting of toe during design stage significantly deteriorates tire durability and leads to uneven tire wear. In the present scenario of automotive industry, toe setting is majorly an iterative or a trial and error process which is both time consuming and involves higher development cost as there may be instances where 2 to 3 sets of iterations are needed before specification is finalized for production. Therefore, determining optimum toe setting at an early stage of a product development will not only save significant development time but it will also benefit in reducing product validation time and cost.

Fatigue life estimation of automotive components is a critical requirement for product design and development. Automotive companies are under tremendous pressure to launch new vehicles within short duration because of customer’s changing preferences. There is a necessity to have a comprehensive virtual simulation and robust validation process to evaluate durability of vehicle as per customer usage. Test track and field test are two of the most time-consuming activities, so there is a need of simulation process to substitute these requirements. This paper summarizes the overall process of Accelerated Durability Test with measured road loads. Based on category of vehicle, type road profiles and the customer usage pattern, the wheel forces, strains and acceleration are measured which is used to derive the equivalent duty cycles on proving ground. The wheel force transducers (WFT) are used to derive loads for fatigue life estimation.

Customer perceived quality (CPQ) of the car is the impression of excellence that a customer experiences the brand through sight, sound, touch, and scent. Molded-in-color (MIC) bumper’s aesthetic appeal contributes significantly to the CPQ of the car. Typical parameters used to define CPQ are color, gloss, grain definition, grain depth, geometry and draft. In this work the durability of the color and gloss post ageing is understood by using analytical and characterization tools. Using the results of ageing characterization, an attempt has been made to understand the retained newness of MIC bumper.

Structural elastomer components like bushes, engine mounts are required to meet stringent and contrasting requirements of being soft for better NVH and also be durable at different loading conditions and different road conditions. Silent block bushes are such components where the loading in radial direction of bushes are high to ensure the durability of bushes at high loads, but has to be soft on torsion to ensure good NVH. These requirements present with unique challenge to optimize the leaf spring bush design, stiffness and material characteristics of the rubber. Traditionally, bushes with varying degree of stiffness are selected, manufactured and tested on vehicle and the best one is chosen depending on the requirements. However, this approach is costly, time consuming and iterative. In this study, the stiffness targets required for the bush were analysed using static and dynamic load cases using virtual simulation (MSC.ADAMS).

For meeting upcoming BS IV & BS V emission norms in Heavy Commercial Vehicles, most of the manufacturers are taking SCR after treatment route. Though SCR system is more complex and involves higher cost impact, an optimized SCR system can bring down the payback period to about one year due to improved fuel economy. For development of an SCR after treatment system, selection of a correct SCR catalyst and its position in the system is very important. NOX conversion efficiency of catalyst depends on exhaust gas temperature at the catalyst and the velocity distribution over the face of the catalyst. Generally catalysts are evaluated for the conversion efficiency in engine test bed. In a drive to have a first-time-right solution, a CFD analysis was carried out considering the low and high flow rate conditions. CFD simulation models and the corresponding results were used as a predictive tool in the exhaust system development process.

This paper deals with setting of Inspection parameters for selected automotive transmission parts in various bench tests. This paper we are discuss about critical dimension's measured for particular type of test. It is not possible to measure all the dimensions of a component for doing a particular test. This is due to time constraints set by program delivery deadlines. From above statement it can be deduced that it is almost impossible to measure all dimensions of a component. A bench level test may consist of two major tests. They are maximum load test and gear shift durability test. The maximum load test deals with gear box durability test and torque carrying capacity of gearbox. Parameters to be measured for some of above parts will be identified. More importantly it will also identify see reasons for that parameter to be measured.

Recent development in automobile industries has seen increased customer attention for good door slamming noise. One of the constituent which plays major role in building brand image of vehicle in terms of NVH performance is door slam noise quality. Hence it is very desirable to understand how different door elements radiate sound during a door-closing event and how to optimize a door structure to achieve specific sound target in order to ensure the door closing noise quality, NVH engineers needed to look at contributions from different door subsystems. The use of statistical tools like Six Sigma can further help them to ensure the consistency in results. This paper explains the systematic approach used to characterize different element of door which contributes to the overall door slam noise quality through QFD (Quality Function Deployment) and contribution analysis. The different mechanisms contributing to door slam noise were studied.