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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.

With rapid improvement in the road infrastructure the average turnaround time of the cargo vehicles has been reduced by 25%.New generation commercial vehicles has better power to weight ratio by integrating high horse power engines. With this latest vehicle configuration average speed of fleet is increased by 30% and more focus is provided towards vehicle safety and handling. Driver confidence on vehicle handling improves with better on Centre feel and return ability, these two parameters are easily tunable with modern electric power assisted steering system, whereas with hydraulic power assisted system these parameters optimization have adverse effect on other steering performance. This paper covers study of following parameters of hydraulic assisted steering system and its optimization on vehicle handling. 1. Steering Gearbox torsion bar stiffness 2. Steering pump flow 3. Caster angle 4. Steering Gearbox valve curve 5.

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.

In the context of vehicular safety and performance, brake pads represent a critical component, ensuring controlled driving and accident prevention. These pads consist of friction materials that naturally degrade with usage, potentially leading to safety issues like delayed braking response and NVH disturbances. Unfortunately, assessing brake pad wear remains challenging for vehicle owners, as these components are typically inaccessible from the outside. Moreover, Indian OEMs have not yet integrated brake pad life estimation features. This research introduces a hybrid machine learning approach for predicting brake pad remaining useful life, comprising three modules: a weight module, utilizing mathematical formulations based on longitudinal vehicle dynamics to estimate vehicle weight necessary for calculating braking kinetic energy dissipation; and temperature and wear modules, employing deep neural networks for predictive modeling.

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.

In the modern era of automotive industry, occupant comfort inside the cabin is a basic need and no more a luxury feature. With increase in number of vehicles, the expectations from customers are also changing. One of the major expectations from real world customers is quick cabin cooling thru all seasons, particularly when the vehicle is hot soaked and being used in summer conditions. Occupant thermal comfort inside the vehicle cabin is provisioned by a mobile air conditioning (MAC) system, which operates on a vapor compression-based cycle using a refrigerant. The main components of a direct expansion (DX) based MAC system are, a compressor, condenser, evaporator, and expansion valve. Conditioned air is circulated inside the cabin using a blower, duct system and air vents. The AC condenser is the most critical component in AC circuit as it rejects heat, thereby providing for a cooling effect inside the cabin.

AC system provides the human comfort inside the cabin of a vehicle but at the expense of consumption of energy from the vehicle. On a global perspective for the bus segment, there is an increased demand for cooling in tropical countries. Optimization needs to be done in existing AC systems w.r.t packaging, cost & performance constraints. Major elements contributing to heat ingress are engine hood, front firewall, windshield & side glasses and bus body parts. Due to these reasons inadequate passenger comfort and poor cool down performance of the vehicle is observed. This paper refers to the reduction of heat ingress through different DOE (Design of Experiment) in the area of design & validation for duct & vent layout, insulation, glass & paint technology, evaporator blowers. The new duct design has been evaluated using a CFD tool by varying various parameters to generate desired output. The integrated use of the modifications was found significant improvement at vehicle level.

The automotive industry is facing a challenge as efficiency improvements are required to address the strict emission norms which in turn requires high performance downsized, lightweight IC engines. The increasing demand for lightweight engine needs high strength to weight ratio materials. To meet high strength to weight ratio, castings are preferable. However due to strength limitations for critical crankshaft applications, it forces to use costly forgings such as micro alloyed forging steel and Martensitic (after heat treatment) forging steel. To reduce the cost impact, high strength Austempered Ductile iron (ADI) casting is developed for crankshaft applications to substitute steel forgings. Austempered Ductile Iron is having an excellent mechanical properties due to aus-ferritic structure. The improved properties of developed ADI Crankshaft over steel forged crankshaft offers additional weight advantage.

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.

Leaf springs are used for vehicle suspension to support the load. These springs are made of flat sections of spring steel in single or in stack of multiple layers, held together in bracketed assembly. The key characteristics of leaf spring are defined as ability to distribute stresses along its length and transmit a load over the width of the chassis structures. The most common leaf spring steels are carbon steels alloyed with Cr and micro-alloyed with Ti, V and Nb. The specific thermomechanical process and alloying elements result in specific strength and fatigue properties for spring steels. The unique properties which facilitate use of spring steel in leaf spring suspensions are ability to withstand considerable twisting or bending forces without any distortion. The microstructure of these steel determines the performance and reflects the process of steel manufacturing. The performance is mainly determined by evaluating fatigue life durability.

Corrosion in automotive industry is broadly categorized into cosmetic & perforation corrosion. Cosmetic corrosion comprises of superficial red rust which is deleterious to the overall aesthetic appeal of the vehicle but can be rectified. Perforation corrosion involves complete erosion of the panel, compromising structural integrity of the respective part. Perforation corrosion demands part replacement. In order to tackle this menace, automotive OEMs have formulated varied corrosion strategies in terms of selection of appropriate substrate, part design & surface protection scheme. Validation of various corrosion strategies become pivotal during the development phase of various parts and assemblies. Traditionally, Salt Spray Test (SST) has been used to determine corrosion life of materials/parts/assemblies. This test however does not simulate real-world conditions.

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.

HVAC system design has an accountability towards acoustic comfort of passengers of a vehicle. Owing to larger cabin volume of a bus, multiple air blowers have to be installed to ensure comfort of passengers. Such multiple blowers produce significant flow induced noise inside the cabin. For commercial success, it becomes essential to predict intensity of such a flow induced noise at very early stages in product development. Conventionally sliding mesh based CFD approach is deployed to predict flow and turbulence noise around each blower. However due to complexity, this method becomes computationally intensive resulting in cost and time inefficiency. Hence it is desirable to innovate around an alternative rapid, reliable prediction method, which ensures quick turnaround of prediction.

Twist-beam suspensions are an example of design solution presenting acceptable performance when applied to passenger cars & light vehicles and it can provide an optimal between cost & performance in the automotive market. For these reasons, twist beam is quite popular in use in rear suspension of light vehicles. In contrary to other types of suspension, the twist-beam has a flexible torsion beam connecting the swing arms. The study of the deformation of this flexible element becomes important to understand its performance and durability behavior. As the name signifies, twist beam major performance attribute is control of twist or opposite wheel travel arising from vehicle roll or road input. Current approach for the study this deformation is through FEA & Multi-body dynamics software tools.

Lift axles of heavy commercial vehicles are deployed to handle increased payload. These axles of Commercial vehicles are made of low alloy carbon steel materials. Lift axles are designed in hollow condition for weight reduction opportunity. Two types of tube materials are used for the manufacturing of lift axles. These are either Cold Drawn Seamless (CDS) tubes or Hot Finished Seamless (HFS) tube material. The vanadium micro-alloyed steel grade, 20MnV6 is an excellent choice for the manufacturing of lift axles. The 20MnV6 has favorable mechanical properties for lift axles and also offers good weldability. However, lift axles made of 20MnV6 when manufactured in hot-finished condition, shows significant scatter in terms of durability performance. This requires further heat treatment of 20MnV6 to be deployed for reducing the scatter in the material properties to reduce scatter in durability performance and thus increasing the reliability of the lift axles.

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.

Automotive suspension system forms the basis for the design of vehicle with durability, reliability and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The growing demand for light-weighting has culminated into numerous designs of rear twist beam suspension systems. However these designs drive their design flexibility by incorporating multiple welding joints into the suspension system. Welding joints helps in designing complex automotive systems. However, these welding joints bring in weak points as welding process itself degrades parent material and introduces areas with high tensile residual stresses. These areas with tensile residual stresses are susceptible to undergo fatigue failure. Thus, there is a need to improve welding process to mitigate harmful tensile residual stresses.

Electric radiator fan is a vital component within IC and EV passenger vehicle cooling system. However, due to its operation, it induces noise and in-cab vibration affecting human comfort level. This paper primarily focus on FMS (Fan Motor Shroud) assembly induced steering wheel vibrations in a vehicle under idle + AC ON condition. The entire NVH performance was cascaded from vehicle level to component level to evaluate for high steering wheel vibration and its transfer path analysis. Unit level vibrations study was also carried out using a rigid rig under controlled conditions. Based on FMS vibration analysis, it was observed that fan blade rotating imbalance leads the high vibrations within system. Thus, a balancing method with higher precision and accuracy was used to measure and balance the fan under all operating conditions. Sensitivity analysis had been carried out for fan imbalanced boundary conditions and operating speeds.

Currently, automotive industries are using Advanced High-Strength Steels (AHSS) sheet grades to achieve key requirements like light weighting and improved crash performance. But forming of AHSS grades becomes key challenge due to its lesser ductility and edge fracturing tendency during forming. In general, most of the automotive components undergoes shearing operations like blanking and punching which affects the edge ductility of the steel. AHSS grades possess limited edge ductility compared with conventional steel grades which results in edge fracturing due to tensile strain during stretch flanging operation. Stretch flange-ability is an important formability characteristic, which aids in material selection to avoid edge fracturing of complex shaped parts. Material with better stretch flange-ability possess better edge ductility and hence perform better in stretch flanging of sheet metal.

In current scenario, there is trend to use stainless steels in place of carbon steels and aluminized carbon steels for Exhaust application. In response to changing regulatory requirements and durability performance requirements of exhaust systems, the ferritic stainless steels are proven to be best suited for the purpose. There are multiple ferritic stainless steels available as options for exhaust system. The material in an exhaust system is subject to heat, oxidation, corrosion and condensate. These environment condition demands that exhaust material should possess high temperature corrosion and oxidation resistance along with required mechanical performance such as vibration and thermo-mechanical load cycles. This work is an attempt to develop simulated test methods for corrosion and thermal environment and evaluate performance of commonly used ferritic stainless steels.