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Transmission of vibration and noise to the occupants and especially driver contributes significantly to the quality perception of the motor vehicle and eventually, it affects the overall ride comfort. These forces mainly reach to customer through tactile locations, i.e. floor, gearshift lever, steering wheel and seat. Showroom/Parking customer drive pattern of a vehicle evinces the steering system and driver’s seat rail vibration as strikingly linked aspect to evaluate human comfort [1]. This paper deals with the study of vibration at steering wheel and seat affecting human comfort at engine idle rpm with AC ON and OFF condition for passenger vehicles. The transmissibility of engine and radiator induced vibrations has been investigated with respect to modal alignment of steering and seat system.

In present day passenger cars, Mobile Air Conditioning (MAC) system is one of the essential features due to rise in overall ambient temperatures and comfort expectation of customers. During the development of MAC system, the focus is on cooling capacity of system for maintaining in-cabin temperatures. However, parameters like solar radiation, air velocities at occupant, relative humidity, metabolic rate and clothing of occupants also influence occupant’s thermal comfort and normally not considered in design of the MAC system. Subjective method is used to evaluate thermal comfort inside vehicle cabin which depends mainly on human psychology. To better understand the effect and minimize the human psychological factors a large sample of people are required. That process of evaluating the comfort inside the vehicle cabin is not only time consuming but also impractical.

Spot-weld joinery plays a major role in maintaining structural integrity of vehicle during an accident scenario. Robust failure definitions are important for accurate prediction of spot-weld failure in crash safety simulations. Spot welds have a complex metallurgical structure, consisting of fusion and heat affected zones. Identifying material failure definitions for huge number of spot-weld joint combinations in a typical Body in White (BIW) of a vehicle is highly challenging. In conventional LS-DYNA-MAT100 material model, spot-weld failure prediction accuracy is limited under complex crash loading scenarios, especially angular and bending load conditions. In order to enhance the failure predictions, a novel mathematical failure model is developed by considering instantaneous resultant loading along with bending moment as a key failure parameter to determine spot weld joint failure.

Potholes are a major cause of discomfort for riders and vehicle damage. The passive suspension systems which are used in the passenger vehicles are primarily reaction based. These can’t adapt to the changing road conditions which means the best ride quality and handling characteristics cannot be ensured for different driving situations. Passive suspension system also needs more maintenance due to its inability to reduce the impact of the road irregularities. In recent years, semi-active suspension systems have been developed to improve ride comfort and vehicle safety. This paper covers the integration of a semi-active suspension system with a road preview mechanism with a TATA car model to investigate its impact on ride comfort, handling characteristics and component loads in digital domain. A quarter car vehicle model is used to compare different active damping control strategies.

Driving dynamics performance is one of the key customer attributes to be developed during product development. In the vehicle development process, freezing the hardware of the chassis aggregates is one of the major priorities to kick off the other vehicle development activities. The current work involves the development of a multilink suspension for an SUV class vehicle. Typically, each OEM performs several product development loops for maturing the vehicle design. The driving dynamics performance evaluation and tuning happens on a physical vehicle with the driver in Loop. Tuning of suspension parameter on the physical vehicle entails actual replacement of parts/components. This encompasses multiple tuning cycles in product development associated with increased cost and test time. To reduce the product development time and cost while delivering first time right chassis configuration, we took an approach of getting driver-in-loop through driving simulator in the concept phase.

Vehicle Ergonomics is one of the most vital factor to be considered in vehicle design and development, as the customer wants a comfortable and performance oriented vehicle. An uncomfortable driving posture can lead to painful driving experiences for longer hauls. The control pedals viz. Accelerator, Brake and clutch pedal (ABC Pedals), are the most frequently used parts in the vehicle, their proper positioning with respect to human anthropology is of prime importance, from driver comfort viewpoint. The methodology currently used for optimizing ergonomics with respect to the positioning of pedals in a vehicle included; measuring anthropometric angles manually with the help of H-Point Machine, subjective jury analysis and through software like RAMSIS, JACK, etc. Manual measurement doesn’t give the flexibility of iterations for optimization. The subjective analysis is based on insinuations thereby, cannot be standardized.

To cope up with the market requirements, OEMs need to react fast and develop advanced and highly refined vehicles keeping in mind multiple factors and Perceived Quality is one of the most important amongst those. Annoying squeak and rattle noises from the vehicle, whether it is new or used car, is the most customer irritant factor; which needs to be addressed in the vehicle development program. BSR (Buzz, Squeak and Rattle) and NVH (Noise, Vibrations and Harshness) performance is the critical in providing quieter experience to the customer and it is becoming more and more important due to transformation from ICE (Internal Combustion Engine) to Hybrid and Electric Powertrains. Among BSR noises, body squeak and creak is the most annoying and difficult to detect and correct, if reported on the prototype test or customer cars. Whereas, squeak and rattles from body fitment and underbody aggregates are relatively easy to address and correct.

Today, noise perceived by the occupants is becoming an important factor driving the design standards for the design of most of the interior assemblies in an automotive vehicle. Buzz, Squeak and Rattle (BSR) is a major contributor towards the perceived noise of annoyance to the vehicle occupants. An automotive vehicle consists of many chassis assemblies which are the potential sources of BSR noise. The potential locations of critical BSR noise could be contained within such assemblies as well as across their boundaries. Engine mount design is major area where BSR noises can be heard inside cabin on various road conditions. Natural rubber is regular rubber used in engine mount applications but in this paper BSR problems are solved by changing the rubber compound i.e., NR+BR (slippery compound). Detailed case study is presented where slippery rubber compound is used which is solving BSR issue and also meeting durability targets.

Steering column and steering wheel are critical safety components in vehicle interior environment. Steering system needs to be designed to absorb occupant impact energy in the event of crash thereby reducing the risk of injury to the occupant. This is more critical for non-airbag vehicle versions. To evaluate the steering system performance, Body block impact test is defined in IS11939 standard [1]. Nowadays for product development, CAE is being extensively used to reduce development cycle time and minimize number of prototypes required for physical validation. In order to design the steering system to meet the Body Block performance requirements, a detailed FE model of Body Block impactor is required. The static stiffness and moment of inertia of body block are defined in SAE J244a [2]. The reference data available in SAE J244a is not sufficient to develop a Body Block model that would represent the physical impactor.

This paper is an application of ISO 26262 functional safety standards for fail-safe design, development and validation of Electric Power Assisted Steering (EPAS) System. As part of safety feature to save lives, prevent injuries and reduce economic loss due to accidents, many research institutes are working to ensure the safety and reliability of emerging safety-critical Electronic Control Systems in automobile applications. As, Advanced Driver Assistance Systems (ADAS) and other emerging technologies are introduced in the automobile application, the overall safety of these advanced electronic systems relies on the vehicle safety systems, such as steering systems. This paper outlines the approach of performing the Hazard Analysis & Risk Assessment (HARA) and developing a Functional Safety Concept. This approach incorporates several analysis methods, including Hazard and Operability study, Functional Failure Modes and Effects Analysis.

The commercial vehicle sector (especially trucks) has major role in economic growth of a nation. With improving infrastructure, increasing number of commercial vehicles and growing amount of Vulnerable Road Users (VRUs) on roads, accidents are also increasing. As per RASSI (Road Accident Sampling System India) FY2016-21 database, commercial vehicles are involved in 43% of total accidents on Indian roads. One of the major causes of these accidents is Driver Drowsiness and Inattention (DDI) (approx. 10% contribution in total accidents). This paper describes novel driver-in-loop performance assessment methodology for comprehensive verification of Driver Monitoring System (DMS) for commercial vehicle application. Novelty lies in specification of test subjects, driving styles and variety of road traffic scenarios for verification of DMS system. Test setup is made modular to cater to different platform environments (Heavy, Intermediate, Light) with minor modifications.

The vehicle crash signature (here on referred as crash pulse) significantly affects occupant restraints system performance in frontal crash events. Restraints system optimization is usually undertaken in later phase of product development. This leads to sub-optimal configurations and performance, as no opportunity exists to tune vehicle structure and occupant package layouts. In concept phase of development, crash pulse characterization helps to map occupant package environment with available structure crush space and stiffness. The crash pulse slope, peaks, average values at discrete time intervals, can be tuned considering library of restraints parameters. This would help to derive an optimal occupant kinematics and occupant-restraints interaction in crash event. A case study has been explained in this paper to highlight the methodology.

During every clutch engagement energy is dissipated in clutch assembly because of relative slippage of clutch disc w.r.t. flywheel and pressure plate. Energy dissipated in clutch is governed by many design parameters like driveline configuration of the vehicle vis-a-vis vehicle mass, and operational parameters like road conditions, traffic conditions. Clutch burning failure, which is the major failure mode of clutch assembly, is governed by energy dissipation phenomenon during clutch engagement. Clutch undergoes different duty cycles during usage in city traffic, highways or hilly regions during its lifetime. A test schedule was derived using energy dissipated during every clutch engagement event as a base and using road load data collected on the vehicle. Road load data was collected in different road mix conditions comprised of city traffic, highway, hilly region, rough road for few hundred kilometers.

Today's automotive industry demands high quality component as well as system designs within very short period of time to provide more value added features to customers on one hand and to meet stringent safety standards on the other. To reconcile economy issues, design optimization has become a key issue. In the last few decades, many OEMs took to analytical tools like Computer-Aided-Engineering (CAE) tools in order to decrease the number of prototype builds and to speed up the time of development cycle. Although such analytical tools are relatively inexpensive to use and faster to implement as compared to the costly traditional design and testing processes: however, there are many variables that CAE tools cannot adequately consider, such as manufacturing processes, assembly, material anisotropy and residual stresses. Therefore, still smart measuring and testing techniques are required to substantiate the CAE results.

EU directive 2005/64/EC on type approval of motor vehicles with respect to their Reusability, Recyclability and Recoverability ( RRR ) requires vehicle manufacturers to put in place the necessary arrangements and procedures for Parts, Materials and Weight (PMW ) data collection from full chain of supply. This is required to perform the calculations of recyclability rate and recoverability rate in line with ISO 22628. Commonly practiced data collection methodologies included spreadsheet and use of internationally available IT support system for collection of material data. Data complexity and prohibitive cost for using Internationally available IT Support systems like IMDS (International Material Data System) has led to the in-house development of IT enabled Solution customizing Siemens PLM software product (Team centre Enterprise) and SAP (SRM suite).

Vehicle aesthetic appearance is critical factor in the perceived quality of a vehicle. Auto OEM focuses on the improvement of perceived quality. The perceived quality of a vehicle is improved by achieving a superior finish on the visible parts. Plastic parts used in visible areas are painted to achieve a superior finish & aesthetic. However, the painting process is very energy intensive, releases a lot of harmful VOCs into the environment, emits carbon di-oxide into the environment & is a very costly process. Also, painted parts pose a challenge for recycling at the end of life. For painting one square meter area, around 6.5 Kg of co2 is released. Additionally, the painting cost contributes to around 60 % of the part cost. As the emphasis has increased on sustainability & reducing the cost, we took the challenge to develop novel mold in color material to eliminate the painting process without compromising the aesthetic & functional requirements of part.

Nowadays automotive cabin comfort has become a necessity rather than an optional feature, with customers demanding more comfort features. Thermal comfort becomes an essential part of this expectation. Since steering wheel is the first surface that the driver will touch once he enters the vehicle, maintaining thermal comfort of steering wheel becomes important, especially in tropical countries like India where a car parked in hot weather can get significantly warm inside. In this work, two design concepts for automotive steering wheel thermal control based on thermoelectric effect are depicted along with a detailed mathematical model. Thermoelectric coolers were selected for this purpose as it is solid state, compact & scalable solution to achieve rapid cooling rates. This was the desired feature expected from an integration standpoint in automotive architecture.

Automotive door seal has an important function which is used extensively where interior of the vehicle is sealed from the environment. Problem with door seal system design will cause water leakage, wind noise, hard opening or closing of doors, gap and flushness issue which impair customer’s satisfaction of the vehicle. Moreover, improper design of seal can lead to difficulty in installation of door seal on body panel. The design prudence and manufacturing process are important aspect for the functionality and performance of sealing system. However, the door sealing system involves many design and manufacturing variables. At the early design stage, it is difficult to quantify the effect of each of the multiple design variables. As there are no physical prototypes during rubber profile beading-out stages, engineers need to carry out non-linear numerical simulations that involve complex phenomena as well as static and dynamic loads for door seal.

Success of the vehicle in the market depends on comfort provided while usage, which also include level of noise, vibration and harshness (NVH). In order to achieve good cabin comfort, the NVH levels have to be as low as possible. Powertrain is main source of NVH issues on vehicle and typically mounted on vehicle using rubber isolators. The dynamic characteristics of rubber isolators play vital role in reducing the vibrations transfer from powertrain to vehicle structure while operation and during dynamic conditions. Traditionally, isolators are manufactured using Natural Rubber (NR) to meet functional requirements which include vibration isolation and durability. At times either of above requirements has to be compromised or sacrificed due to the limitation in compounding process and other practical problems involved with manufacturing of rubber parts.

Success of the vehicle in the market depends on comfort provided while usage, which also includes noise, vibration and harshness (NVH). In order to achieve comfort level, the NVH levels have to be as low as possible. Powertrain is the main source of NVH, in which internal combustion engine consists of crank shaft and balancer shaft. Crank shaft gear is connected and driven by crank shaft and balanced by integral eccentric mass coupled with gear. Balancer shaft is used for additional balancing of rotating masses. Pair of crank shaft and balancer shaft gears generates noise and vibration when unbalance in the system and backlash in the gears increase while usage. The practice of interposing a vibration isolator on the surface of gear has been so far resorted for preventing transmission of vibration, therefore reduction in noise. In the work presented, balancer gear was made with sandwich design to reduce noise. Sandwich design comprises of Inner hub and outer ring with lug projections.