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Durability is an important indicator to measure the automobile quality and reliability. Automotive industry is striving to develop products having excellent performance to weight ratios and along with high safety standards. A successful product should have adequate robustness during normal customer operation and the ability to withstand high impact events without impairment of function or safety relevant damage. Road Load Data Acquisition (RLDA) along with efficient design and validation processes are, among others, critical factors for success in the automotive industry. Physical RLDA is expensive and time consuming, the prototype vehicles being costly and only available at a later stage in the vehicle development cycle. Component failures occurring on the proto test vehicles can prove to be a major setback, delaying the product launch by months. In order to overcome above challenge, this paper presents an innovative methodology to carry out Digital RLDA (dRLDA).

Polymers are substituting traditional materials, such as metals, in existing as well as new applications, both for structural and aesthetic applications as they are lightweight, customizable and are easy to mould into complex shapes. With such an extensive use of polymers, there is a need to carefully scrutinize their performance to ensure reliability. This is particularly the case in the automotive and electronic industries where the aesthetic appeal of their products is of prime concern and any visible scratch damage is undesirable. Concern for aesthetics has led to a need for the quantification of visibility due to scratch damage on polymeric surfaces Many painted plastic parts used in vehicles are being replaced with the molded-in color plastics for cost reduction and also due to environmental concerns associated with solvent emissions. There are multiple methods used for scratch evaluation of polymers and paints.

The automotive application places very special demands on the air conditioning system. As is the case with any other process, system efficiency is very important and the automotive air-conditioning application is no exception. While the characteristics of all the major components in the air conditioning system like compressor, condenser, evaporator and blower contribute to overall system efficiency, localized inefficiencies do play a part and so must be kept to a minimum, especially in this day and age when extra emphasis is being laid on sustainability. One such phenomenon that contributes to the system inefficiency is heat pick-up in suction line. Since the temperature at the evaporator-outlet is quite lower than ambient and also its surroundings (steering system pipes and hoses, engine, air intake pipes and so on), the refrigerant picks up heat as it moves along the suction line up to the compressor inlet. This heat pick-up is detrimental to the overall system performance.

Diesel engine fuel hose return line is considered as a low pressure line and consists of two layers. The inner layer is used to carry the excess fuel, thereby hose material shall have resistance to fuel and its residues. The outer layer is used to protect inner layer from heat, ozone and oil spillage, thereby outer cover material shall have resistance against the heat, ozone and engine oil. Currently NBR PVC, NBR and FKM materials have been used as inner layer materials in diesel engine fuel hose outer cover application, according to service temperature. Halogen contained CSM material has been used for outer cover application and the production of CSM material was withdrawn by one of the major manufacturer recently. Current global challenge is to use environment friendly material in vehicle components to make hazardous free environment. To replace CSM material, which contains Halogen, the available options are CPE, CR, HNBR and AEM materials.

Apart from being an active safety system the brake system represents an important aspect of the vehicle dynamics. The vehicle retardation and stopping distance completely depend upon the performance of brake system and the functionality of all components. However, the performance prediction of the entire system is a challenging task especially for a complex configuration such as multi-axial vehicle applications. Furthermore, due to its complexity most often the performance prediction by some methods is limited to static condition. Hence, it is very important to have equivalent mathematical models to predict all performance parameters for a given configuration in all different conditions This paper presents the adopted system modelling approach to model all the elements of the pneumatic brake system such as dual brake valve, relay valve, quick release valve, front and rear brake actuators, foundation brake etc.

In today’s automobile market, most OEMs use manual transmission for cars. Gear Shifting is a crucial customer touch point. Any issue or inconvenience caused while shifting gears can result into customer dissatisfaction and will affect the brand image. Synchronizer is a vital subsystem for precise gear shifting mechanism. Based on vehicle application selection of synchronizer for given inertia and speed difference is a key factor which decides overall shift quality of gearbox. For more demanding driver abuse conditions like skip shifting, conventional brass synchronizers have proved inadequate for required speed difference and gear inertia, which eventually results into synchronizer crashing and affects driving performance. To increase synchronizer performance of multi-cone compact brass synchronizer, a ‘Grit blasting process’ has been added. These components tested with an accelerated test plan successfully.

Basic Function: Vehicle remote is used for vehicle lock/unlock/search/Hazard lights /approach light functions for customer convenience and vehicle security system. Conventional approach: 1 Use of separate RF (Radio Frequency) receiver -Additional Cost impact. 2 High remote RF power - Reduced remote battery life and bigger remote size required 3 High sensitivity RF receiver - High cost. Low Cost approach: It involves the followings: 1 Integration of RF receiver inside the Body Control Module (BCM). 2 Low Power Remote and Optimization of Remote PCB layout to get the maximum power. 3 External wired antenna taken out from BCM and proper routine need be ensured to get the best performance. 4 BCM mounting location to get the best remote range in all vehicle directions. This paper relates to the methodology for low cost approach for the RF communication between remote transmitter and receiver with achieving the best remote performance at vehicle level condition.

A hydraulic-assisted power steering system on a vehicle has a steering pump which is directly driven from the engine continuously. In real world, the assistance from the steering pump is useful only while maneuvering. During a typical highway drive, assistance from this power steering pump remains unused for majority (76%) of the time; although the continuously rotating power steering pump keeps consuming energy from the engine. An electronic controller has been provided for the electro-magnetic pairing device of the power steering pump in order to provide assistance for steering based on driver demand only. The electromagnetic pairing device integrated on the steering pump can be made to engage/disengage based on the driver demand through the electronic controller.

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.

Vehicle floor vibration is the resultant of different road inputs damped through various transfer paths. Seat comfort, which depends on these floor vibrations, can be evaluated with a single input signal “Pink noise”; which constitutes various road inputs. Transmissibility of seat structure on a vibration shaker with pink noise input includes all possible responses of road inputs. Still, transmissibility profile at vehicle end and component level varies. This is due to the utilization of “dummy” on component level testing on vibration shaker, which acts as a dead weight with dissimilar damping characteristics of human. A transmissibility correlation between human and dummy is attained by replacing the dummy in place of human and actuating it to find the difference in contribution between them for different class of vehicles. This contribution extrapolation from the damping effects of human and dummy is applied on dummy transmissibility.

Pedestrians are a vulnerable road user group, comprising 22% of global road traffic deaths [1]. In Japan, pedestrian fatalities accounted for 28% of total road fatalities and approximately 16% in Australia. These figures compare with 13% for the USA and 40-50% for India and Thailand [2]. Various pedestrian safety requirements are mandated in different markets in recent years worldwide. For pedestrian head-form, vehicle front-end styling and the free package space below bonnet plays a vital role in deciding the pedestrian head-form safety performance. Currently during initial phase of vehicle development, the free package space requirement is decided based on benchmark data. However, the benchmarking data does not give any insight into the physics involved and is subjective in nature as it varies from vehicle to vehicle. This paper gives an analytical approach for defining the free package space requirements for meeting the targeted pedestrian head form performance requirements.

Brake system is the most important system in the vehicle considering the overall vehicle safety and speed control. Brake applications are repetitive during a city traffic and hilly terrain on downhill gradient. Frequent braking gives rise to an overheating of the brake drum and its components. Braking operations at high temperature gives rise to problems like reduced deceleration due to loss of brake pad friction characteristics, pad softening and sticking to drum, pad distortion and wear etc. All these factors collectively result in deterioration of the braking performance and reduction of brake pad durability with time. Till date most of the thermal analysis performed for brake drum heating are through physical testing using brake system prototypes and by means of CFD tools. These methods are time consuming and expensive. There is a need for an alternative method to reduce physical trials and prototype building and reduce dependency on CFD analysis.

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.

The fuel economy of heavy commercial vehicles can be significantly improved by reducing the rolling resistance of tires. To reduce the rolling resistance of 6×4 tractor, the super single tires instead of rear dual wheel tires are tried. Though the field trials showed a significant increase in fuel economy by using super single tires, it posed a concern of road safety when these tires blowout during operation. Physical testing of tire blowout on vehicle is very unsafe, time consuming and expensive. Hence, a full vehicle simulation of super single tire blowout is carried out. The mechanical properties of tires such as cornering stiffness, radial stiffness and rolling resistance changes during the tire blowout; this change is incorporated in simulation using series of events that apply different gains to these mechanical properties.

The interior components of a passenger vehicle are designed to provide comfort and safety to its occupants. In the event of accident, vehicle interiors are primary source of injuries when occupants interact with them. Vehicle interiors consists of Instrument panel (IP), center console, seats and controls in front of seating position etc. Severity of the injuries depends on the energy dissipating characteristics, profiles, projections of different interior components. These are assessed by ECE R21 and IS12553 head form impact tests. To evaluate the Head form impact performance on Interior components, Computer Aided Engineering (CAE) simulations are extensively used during the vehicle development. In order to predict failure of plastic components and snap joints which might lead to expose sharp edges, it is critical to model plastic material and snap joint.

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.

Vehicle crashworthiness is an important aspect of vehicle development. Vehicle structural performance plays a critical role during crash for controlling the occupant injuries. During a crash event, vehicle energy management governs the structural performance and passenger compartment integrity. However, these parameters are dependent on material properties such as yield/ultimate tensile strength, work hardening effects, strain rate dependency, material elongations and material fracture strains. Appropriate representation of these material properties in CAE (Computer Aided Engineering) environment is very critical for reliable prediction of vehicle structural performance during development phase. Among all material properties, material fracture strain is the most complex one and needs detailed material characterization approach for failure definitions.

Rubber hose and metallic pipe with crimped joints are extensively used in steering system assembly, transmission oil cooler system, brake system etc. to carry hydraulic fluid or lubricants from one place to another. The pipe and rubber hose assembly provides necessary flexibility for complex routing on the vehicle level. Design of hose and pipe assembly for this application are different due to difference in operating pressure and temperature requirement for vehicle application. This paper defines the criteria for design and validation of hose & pipe assembly used to connect automatic transmission with the cooler. Crimped joints are validated for their separation force, leakages, ability to withstand pressure pulsations, burst test etc. Parameters which influence the hose & pipe assembly durability are pipe end flaring dimensions, type of crimping, reinforcement type, its size, material and pattern, rubber material properties, crimping force, effective crimping diameter etc.

Single plate dry clutch is one of the most abuse components in the vehicle. With the growing population of traffic in cities, useful life of clutch is affected drastically which is evident from the rise in complaints on clutch from metropolitan cities. The governing design parameter, which affects the life of clutch, is the energy dissipated in clutch per unit area of friction lining of clutch disc. The life of clutch is affected by many factors like vehicle weight, engine torque, driveline ratios, friction lining, size of clutch, which are taken into consideration during design stage of the clutch. Apart from these factors, one more factor, engine calibration, affects the clutch life drastically. However, it is not taken into consideration during design stage owing to its inherent nature as it gets matured over the vehicle development program.