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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.

Electrical and Electronic systems in a vehicle are increasing manifolds with Electric and ADAS Vehicles taking the lead. There is a rapid transition happening from hardware driven vehicles to software driven vehicles. ISO 26262 is a global standard defined for functional safety (FuSa) in the automotive industry which addresses the structured design and development approach for eliminating electrical malfunctions leading to critical hazards such as fire in EVs. The standard defines specific requirements that need to be met by the safety relevant electrical system and also by development processes. Though the implementation of FuSa is crucial from vehicle safety point of view, its compliance is still a challenge majorly due to lack of awareness, in-built complexities, increase in project development time and subsequent cost. In this work, we focus on a FuSa implementation model taking into account the conventional new program development cycle.

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.

Today, most vehicles in developing countries are equipped with air conditioning systems that work with Hydro-Fluoro-Carbons (HFC) based refrigerants. These refrigerants are potential greenhouse gases with a high global warming potential (GWP) that adversely impact the environment. Without the rapid phasedown of HFCs under the Kigali Amendment to the Montreal Protocol and other actions, Earth will soon pass climate tipping points that will be irreversible within human time dimensions. Up to half of national HFC use and emissions are for the manufacture and service of mobile air conditioning (MAC). Vehicle manufacturers supplying markets in non-Article 5 Parties have transitioned from HFC-134a (ozone-safe, GWP = 1400; TFA emissions) to Hydro-Fluoro-Olefin, HFO-1234yf (ozone-safe, GWP < 1; TFA emissions) due to comparable thermodynamic properties. However, the transition towards the phasing down of HFCs across all sectors is just beginning for Article 5 markets.

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.

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.

Structural automotive components are subjected to fatigue damage under cyclic stresses and strains. The fatigue damage initiates at stress levels lower than the elastic limit of the material and results in cracks. The Initial fatigue cracks are difficult to detect, such cracks can develop rapidly and cause sudden and brittle failure in structures. Many structural automotive components are fabricated involving weld induced local conditions such as geometry of weld toe and localized tensile residual stresses. These conditions are favorable for initiation of fatigue damage at weld toe. In current work, sever plastic deformation (SPD) which is based on high frequency impact treatment using ultrasound energy was applied on weld toe of representative weld joints. The effect of SPD on weld toe geometry modification, microstructure and residual stresses were evaluated. Microscopic and X-ray diffraction techniques were used to study the effects of SPD.

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.

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.

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.

Transportation has significant and long-lasting economic, social and environmental impacts which makes it an important dimension of urban sustainability. The World is witnessing rapid changes in modern traveling behavior, and efforts are continuously being made to stimulate sustainable mobility solutions with smart policies, new business models, and advanced technologies (connected cars, sensors, electrification). However, the shift is gradual in India when compared to developed countries due to unique barriers to emerging green mobility solutions. This paper empirically investigates public travel satisfaction and the primary factors for the selection of modes for different types of commutes. Quantitative data were collected including socio-demographic, travel mode choices, and preferred future mobility solutions from the western states of India.

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.

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.

The torque required to tighten any threaded joint is different from the necessary torque to untighten threaded bolt or nut, and it is not observed or widely known since this is a regular and straightforward operation. Typically the torque needed to untighten a newly tightened clamp is around 10% to 30% less than the torque to stretch it further. During tightening a threaded bolt, a significant amount of torque required to overcome friction in the threads and under the nut face. The proportion of the torque used to overcome frictional resistance depends upon the friction value. When we tighten a joint with a coefficient of friction of 0.12, only about approximately 14% of the torque required to stretch the fastener producing the clamp load with 86% of the torque is lost overcoming friction. The torque needed to pull the bolt always acts in the untightening direction, resulted in untightening torque lags behind the tightening torque.

This paper takes a review of fretting phenomenon on splines of the engaging gears and corresponding splines on shaft of automotive transmission and how it leads to failure of other components in the gearbox. Fretting is a special wear process which occurs at the contact area of two mating metal surfaces when subject to minute relative oscillating motion under vibration. In automotive gearbox, which is subjected to torsional vibrations of the powertrain, the splines of engaging gears and corresponding shaft may experience fretting, especially when the subject gear pair is not engaged. The wear debris formed under fretting process when oxidizes becomes very hard and more abrasive than base metal. These oxidized wear particles when comes in mesh contact with nearby components like bearings, gears etc. may damage these parts during operation and eventually lead to failure.

The primary function of an engine mounting bracket is to support the powertrain system in all road conditions without any failure. The mount has to withstand different road conditions and driving maneuvers which exert loads on it. Also, it is challenging to change the mounting locations and types after the engine is built; hence it is paramount to verify the mounting brackets against all abuse loads in the design stage. The Car manufacturers ensure engine mount bracket design meets CAE's (Computer-aided engineering) static and fatigue load cases. The CAE is performed using digital RLD (Road load data) loads. The design checks cumulative strain or stress against specified service life requirements during break and fatigue FOS (Factor of safety) calculations. However, it is difficult to simulate the material's fracture toughness to estimate the effect of the impact load on the mounting bracket.

This paper discusses the test setup and methodology required to validate complete lift axle assembly for simulating the real time test track data. The correlation of rig vs track is discussed. The approach for reduction of validation time by eliminating few of the non-damaging tracks/events, its correlation with real life condition is discussed, and details are presented. With increased competition, vehicle development time has reduced drastically in recent past. Bench test procedure using accelerated test cycle discussed in this paper will help to reduce development time and cost. Process briefed in this paper can also be used for similar test specification for other structural parts or complete suspension system of heavy commercial vehicles.

This paper deals with specific NVH related issues attributed due to LCA bush stiffness and Brake rotor DTV. While the focus is on the cause of such vibration (judder while braking at 120 kmph), the presentation goes to the root-cause of judder and how various suspension/tire/brake components contribute to the generation/amplification of such vibration. Results are presented for twist blade types of vehicle suspensions, along with procedures that were developed specifically for this study and some of the actual case study. DTV-Disk thickness variation

Automotive suspension system forms the basis for the design of vehicle with durability, reliability, dynamics 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 current focus in automotive industry is to reduce the weight of the automotive parts and components without compromising with its static and dynamic mechanical properties. This weight reduction imparts fuel efficiency with added advantages. High-Strength Low Alloy steel (HSLA) offers optimum combination of ductility, monotonic and cyclic mechanical properties. Furthermore, welding processes offer design flexibility to achieve robust and lightweight designs with high strength steels.