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Aeroacoustics of vehicles is becoming an important design criterion as it directly affects passenger’s comfort. The wind noise at highway speeds (>80 KMPH) is a critical quality concern under normal and crosswind conditions and dominant factor in assessing acoustic comfort of the vehicle. Wind noise is caused by the vortex air flow around a vehicle body and air leakage through the sealing gaps of attached parts. This majorly contributes to high frequency noise (>250 Hz). Accurate identification and control of noise sources and leakage paths result in improved acoustic comfort of the vehicle. In this paper, aero-acoustic quality characteristics of validation prototype vehicle are studied. The major wind noise sources and leakage paths in the vehicle are identified through in-house blower set up in the semi anechoic room. The overall wind noise level and articulation index of vehicle at various speeds are determined through on- road measurements.

Dual mass flywheel (DMF) is an excellent solution to improve the noise, vibration and harshness (NVH) characteristic of any vehicle by isolating the driveline from the engine torsional vibrations. For the same reason, DMFs are widely used in high power-density diesel and gasoline engines. However, the real-world usage conditions pose a lot of challenges to the structural robustness of the DMF. In the present work, a new methodology is developed to evaluate the robustness of a DMF fitted in a compact sports utility vehicle (SUV) with rear-wheel drive architecture. The abuse conditions (mis-gear, sudden braking, etc) in the real-world usage could lead to a sudden engine stall leading to an abnormally high angular deceleration of the driveline components. The higher rate of deceleration coupled with the higher rotational moment of inertia of the systems might end up in introducing a significantly high impact torque on the DMF.

The main function of an air conditioning system in a vehicle is to provide the thermal comfort to the occupant at minimum possible energy consumption in all environmental conditions. To ensure the best possible thermal comfort, air conditioning system is optimized on various parameters like heat load, air flow distribution, glass area, trim quality, insulations and cabin leak rate. A minimum cabin leakage is regulatory requirements to ensure the air quality of cabin. Anything above the minimum cabin leak rate ultimately turn into reduced thermal comfort and additional energy consumption. The additional energy consumption to maintain the required thermal comfort in the cabin due to cabin leakage affects the fuel efficiency severely. In the present study, the effect of cabin leakage on fuel efficiency and thermal comfort is studied in details by varying the cabin leakage through mechanical means. The experiments are carried out in normal environmental condition and road condition.

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.

The SAE J1100 based standard cargo volume index methods and predefined luggage objects are very specific to United States population. The European luggage volume calculation and standard luggage calculations are primarily based on DIN and ISO standards. Luggage volume declaration by manufacturers are based on any of these methods. The calculations are complicated and there is a possibility of declaring different values for similar luggage compartments. The major purchase decision of vehicle is based on its luggage capacity and current methods are very limited to make an intelligent decision by a customer. Market specific customer usage patterns for luggage requirements and protecting them in vehicle architecture upfront in concept stage is important to retain the market position and buying preference of customers. The usage patterns is collected from customer clinics and marketing inputs.

Recent trends in vehicle occupant protection have led to renewed interest in the perception of Roominess such as headroom, shoulder room and foot room etc. Occupants head room in vehicles is currently measured using tools, procedures and definitions described in SAE J1052 and J1100. “Head Position Contours” defined in SAE J1052 are useful in establishing accommodation requirements for head space [1]. With respect to the Indian Anthropometry database, the head position contour as per SAE J1052 will not be appropriate with Indian population. With this objective in mind a head movement envelope is generated using the software - RAMSIS Digital manikin. RAMSIS is widely used by Automobile Manufacturers for Digital Human Modeling. The head movement envelope is a collation of different movements of head during driving condition.

Transportation system is at the brink of revolution and many new ways of mobility are arising in the market to ease the pressure on the established transportation infrastructure. Many companies and governments around the world are exploring innovative options in the space of shared mobility to reduce the overall carbon footprint. To expedite the adoption of shared mobility in India, it is necessary to make such options comfortable and cost-effective. One of the most effective way to make shared mobility options cost effective is to comfortably increase occupancy per vehicle footprint. This paper aims to evaluate a novel method of occupant seating to identify the maximum number of passengers a vehicle can accommodate without significant impact on occupant comfort. It is assumed that shared mobility options are used for a short duration of commute, and hence the comfort of the seat can be marginally compromised to increase the total number of occupants.

Increasing complexity in E/E architecture poses several challenges in developing comfortable, clean and safe cars. This mandates robust processes to mitigate potential hazards due to malfunction of electronic systems throughout the product life cycle. With the advent of ISO 26262 [1] which provides guidelines for developing safe cars, the process is getting standardized towards safer mobility. In this paper, the functional safety process is briefly covered and a case study of Hazard Analysis and Risk Assessment for specific E/E system is presented. An in-house tool developed for functional safety process and management is covered.

In today’s rapidly evolving automotive world, reduction of time to market has prime importance for a new product development. It is critical to have significant front-loading of the development activities to reduce development time while achieving best in class performance targets. Driver-in-the-loop (DIL) simulators have shown significant potential for achieving it, through real time subjective feedback at preliminary stages of the vehicle development. Recent advances in technology of driving simulators have enabled quite accurate representation steering and handling performance, also good prediction on primary ride and low frequency vibrations. In conventional damper development, the definition of the initial dampers tuning specifications typically requires a mule vehicle, or atleast, a comparable vehicle. However, this approach is associated with protracted iterations that consume substantial time and cost.

The Ride Comfort has always been an important attribute of a vehicle that gets trade-off with handling characteristics of a vehicle. However, to cater the growing customer requirements for better ride comfort in a vehicle without compromising on other attributes, evaluating and achieving optimal ride comfort has become a significant process in the vehicle development. In the current engineering capability and virtual engineering simulations, creating an accurate and real time model to predict ride comfort of a vehicle is a challenging task. The qualitative evaluation of ride attributes has always been the proven conventional method to finalize the requirements of a vehicle. However, quantitative evaluation of vehicle ride characteristics benefits in terms of target setting during vehicle development process and in robust validation of the final intended product against its specifications.

This paper is an attempt to compile a systematic approach which can be easily incorporated in the product development system used in the design and development of parking brake systems for passenger cars having rear drum brakes, which in turn can effectively reduce the lead time and give improved performance. The vehicle GVW, percentage gradient and maximum effort limits (as per IS 11852 - Part 3), tire and drum brake specifications were taken as front loading. This data is used for target setting of functional and engineering parameters, such as lever pull effort, lever ratio and angular travel of lever. Design calculations were performed to obtain theoretical values of critical parameters like lever effort and travel. The comparison between target and theoretical values give the initial confidence to the system engineer. Further, the outcome was taken to conceptualize the hard points of lever on vehicle for ergonomics.

Digital human models (DHM) have greatly enhanced design for the automotive environment. The major advantage of the DHMs today is their ability to quickly test a broad range of the population within specific design parameters. The need to create expensive prototypes and run time consuming clinics can be significantly reduced. However, while the anthropometric databases within these models are comprehensive, the ability to position the manikin’s posture is limited and needs lot of optimization. This study enhances the occupant postures and their seating positions, in all instances the occupant was instructed to adjust to the vehicle parameters so they were in their most comfortable position. While all the Occupants are accommodated to their respective positions which finally can be stacked up for space assessments. This paper aims at simulating those scenarios for different percentiles / population which will further aid in decision making for critical parameters.