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Designers and analysts need to compare and conduct synthesis for selection of materials based on their properties involving simulation, optimization and correlation with test data. An example is that of acoustic material properties such as random and normal incidence sound absorption coefficient and sound transmission loss. The international test standards necessitate having standard operating procedures for characterization of these materials. This procedure is quite involved and addresses steps including test data acquisition, post processing, calculations, classification, report generation and most importantly, storage of such innumerable material properties in a structured manner to facilitate ease of retrieval and updating of properties. It is also highly desirable to have a synergy of the databank directly with simulation tools. Further, all of these steps need to be accurate, non-speculative and quick.

Sound Quality (SQ) of brake and clutch pedal assembly plays an important role in contributing to vehicle interior noise and perception of sound. Quiet operation of brake and clutch units also reflects the vehicle built and material quality. Noise emitted from these sub-assemblies has to meet certain acceptance criteria as per different OEM requirements. Not much work has been carried on this over the years to characterize and quantify the same. An attempt has been made in this paper to study the sound quality of brake and clutch pedal assemblies at component level and validate the same by identifying the parameters affecting SQ. Effect on noise at different environmental conditions was studied with typical operating cycles in a hemi-anechoic chamber. The effect of sensor switches integrated within the clutch and brake pedal on sound quality is analyzed. It is found that the operating characteristics of switches drives the noise and SQ.

A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers.

Ride Comfort forms a core design aspect for suspension and is to be considered as primary requirement for vehicle performance in terms of drivability and uptime of passenger. Maintaining a balance between ride comfort and handling poses a major challenge to finalize the suspension specifications. The objective of this project it to perform ride- comfort analysis for a commercial truck using MATLAB Simulink. First, benchmarking was carried out on a 4x2 commercial truck and the physical parameters were obtained. Further, a mathematical model is developed using MATLAB Simulink R2015a and acceleration- time data is collected. An experimentation was carried out on the truck at speeds of 20 kmph, 30 kmph, 40 kmph and 50 kmph over a single hump to obtain actual acceleration time domain data. The model is then correlated with actual test over a single hump. This is followed by running the vehicle on Class A, B & C road profiles to account for random vibrations.

Energy dispersive X-ray fluorescence (EDXRF) analysis have made it possible to conduct elemental analysis on a variety of fields, including those with environmental, automotive, geological, chemical, pharmaceutical, archaeology, and biological origins. The ability of EDXRF to deliver quick, non-destructive, and multi-elemental analytical findings with increased sensitivity is of great importance. It is a vital tool for quality control and quality assurance applications. Thus, EDXRF plays an important role to compare batch-to-batch products for meeting quality standards. This paper presents application of EDXRF as an effective tool for quick qualitative and quantitative evaluation of given samples.

The paper talks about Quantification of Alertness for vision based Driver Drowsiness and Alertness Warning System (DDAWS). The quantification of alertness, as per Karolinska Sleepiness Scale (KSS), reads the basic input of facial features & behaviour recognition of driver in a standard manner. Although quantification of alertness is inconclusive with respect to the true value, the paper emphasised on systematic validation process of the system covering various scenarios in order to evaluate the system’s functionality very close to the reality. The methodology depends on definition of threshold values of blink and head pose. The facial features are defined by number of blinks with classification of heavy blink and light blink and head pose in (x, y, z) directions. The Human Machine Interface (HMI) warnings are selected in the form of visual and acoustic signals. Frequency, Amplitude and Illumination of HMI alerts are specified.

This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

Biodiesel is an alternate fuel for diesel consisting of the alkyl monoester of fatty acids derived from vegetable oils. The most usual method to transform oil into biodiesel is transesterification which can be carried out using different catalyst. Jatropha is second generation oil which is non edible and can be use for producing biodiesel. The first part is to expel oil from jatropha seeds. There are different types of expelling methods such as mechanical extraction, solvent extraction and enzymatic extraction. The study was conducted with hand driven mechanical expeller which is most conventional way of extracting oil from seeds with mechanical efficiency of 60-80% for single pass. The study includes various combinations of parameters like seed treatment, sun drying, pre-heating, soaking at different temperatures and different de-hulling compositions.

The low running cost of electric two wheelers is resulting in high popularity and growing market share. The electric two wheelers are generally considered silent. However, the tonal nature of radiated noise is annoying for both driver and pedestrians in electric vehicles. This study focuses on electric two-wheeler with annoyance issue. The customer complained about non-linear noise with respect to speed and also whining during loading and coasting. The detailed Noise Source Identification (NSI) revealed that the noise is due to motor and transmission whine and structural resonances of chassis excited by this motor excitation during runup and gear whine orders during coasting when excitation by motor is absent. The motor mounting and chassis are structurally modified with suitable stiffeners and damping based on the results of modal analysis. The transmission gear geometry and contact pattern are optimized for transmission error reduction.

Government of India, in 2017, mandated a Side Impact Test (AIS 099 technically aligned to UN ECE Regulation No. 95.03 series of amendments) on M1 category Passenger Vehicles to ensure protection of occupants in lateral impact accident scenarios. Later, in 2022, a draft notification has been issued by the Government mandating installation of 6 airbags (2 Nos of thorax side airbags, 2 Nos of head protection or curtain airbags in addition to already mandated installation of Driver and Passenger Airbags) in all such passenger vehicles. However, the vehicles fitted with side thorax airbag and curtain airbags are proposed to be assessed as per AIS099 test only. Curtain Airbags are typically installed to protect occupant’s head from severe injuries in narrow object impacts simulated in Pole Side Impact Test Configurations. However, at present, India has not notified an equivalent standard to UN R135 demanding performance of the vehicle in pole side impact scenarios.

With the recent development in virtual modelling and vehicle simulation technology, many OEM’s worldwide are using digital road profiles in virtual environment for vehicle durability load prediction and virtual design evaluation. For precise simulation results, it is important to have the tire digital twin which is the realistic representation of tire in the virtual environment. The study comprises of discussion about different types of tire models such as empirical, solid model, rigid ring model and flexural ring models such as Pacejka, MF Swift, CD tire, F tire etc. and also the complexity involved in development of these tire models. Generation of virtual tire model requires highly sophisticated test rigs as well as vehicle level testing with Wheel Force transducers and other vehicle dynamics sensors. The large number of data points generated with testing are converted in standard TYDEX format to be further processed in various software tool for virtual model generation.

The function of the automotive transmission is to reliably transmit torque and motion between engine and wheels at acceptable levels of noise, vibration and desired life. Gear drive components most commonly subject to distress are the gears, shafts, bearings and seals. The variables in the entire power-system, such as vibration, misalignment, type of lubricant used, material properties, operating temperature and abuse are considered as the main root causes for the gear failures. The bending and contact strength of the gear tooth are considered to be one of the main contributors for the failure of the gear in a gear set. Thus, Heartzian stress analysis has become popular as an area of research on gears to minimize or to reduce the failures of gears. In this research work, one of the major field issues related to 1st gear and reverse gear pitting at very low life for 6 speed manual transmission for mining/ quarry application is studied.

The Indian automotive industry is striving towards more safe and durable vehicles. A need was felt to study the effect of changes in axle static loads on fatigue life of the axle components. Also, there was a need to develop generic test method, as there are no test standards or generic methods available in public domain for fatigue testing of commercial vehicle axles. The study was carried out to check direct effect of change in axle loads on various connections on axle, effect of suspension configuration and force distribution, Vehicle dynamics, etc. In this paper, an India specific generic load spectra was evaluated for accelerated laboratory validation. Paper discusses the methodology as; study of heavy commercial vehicle systems, road load data collection on identified test vehicles w.r.t. test matrix finalized, India specific test loads and load spectra development, normalization of axle load spectra w.r.t to static axle weights and arriving at test guidelines.

Automotive clutches form the most important component in the drive line which acts both as torque transmitter and as a fuse. Testing clutches, in the vehicle assembly, poses certain limitations. In this context the automotive clutch, as a component, needs to be evaluated to determine various performance parameters like wear, load loss, slipping torque, slipping time etc. to meet desired design, performance and durability requirements. It is very important to simulate engine and vehicle conditions in terms of operating environment, speed and load accurately while evaluating above parameters. This creates lot of challenges to design and develop a test rig capable of evaluating complete clutch performance. Very limited options are available for such test rigs worldwide. In India, no manufacturer provides such indigenous test rigs. Developing an indigenous, cost effective clutch test rig was the need of the hour.

Ride is considered to be one of the crucial criterion for evaluating the performance of a vehicle. Automobile industry is striving for improvement in designs to provide superior passenger comfort in Commercial vehicles segment. In Industry, Quarter-car model has been used for years to study the vehicle’s ride dynamics. But due to lower DOF involved in quarter car, the output accuracy is somewhat compromised. This paper aims in development of a 7 DOF full-car Model to perform the ride- comfort analysis for Light Duty 4*2 Commercial Bus using MATLAB Simulink which can be used to tune the suspension design to meet the required ride-comfort criteria. Firstly, experimental data and Physical Parameters are collected by performing Practical Test on commercial Bus on different road profiles. Secondly, a Full Car Mathematical Model with 7 DOF has been developed for a bus using MATLAB Simulink R2018a.

One of the primary reasons for road accidents is driving while distracted or drowsy. Often, long and monotonous road journeys lead to distracted or drowsy driving. Therefore, there is a need for a system which alerts a distracted or drowsy driver. Moreover, as the levels of autonomy move beyond SAE Level 2, the system assumes a larger share of the dynamic driving task. Under challenging circumstances, the system might ask the driver to take back vehicle control. To guarantee safety, it’s crucial to monitor the driver’s condition in order to assess their readiness to regain control of the vehicle. An advanced safety feature known as a driver monitoring system (DMS), sometimes referred to as a driver state sensing (DSS) system, is designed to monitor a driver’s attentiveness and alertness, providing warnings or alerts to refocus their attention on driving when drowsiness or distraction is detected.

The death toll due to traffic accidents in India is on a rise, according to the latest Road Transport ministry report, a total of 4.97 lakh road accident was reported in 2011. Though compared to 2010, the accidents have gone down by 1,945, the number of deaths at 1,42,485 has increased by over 7,000.[1] This paper proposes a design of an Emergency Intimation System (EIS) tailored to fit for Indian consumer needs and available infrastructure. EIS is an emergency alert technology devised to assist drivers and passenger in an event of vehicle crash. Majority of deaths are caused by slow accident response time. EIS is aimed to lower this response time and ensure that the required rescue and medical services are made available in time. This device employed to make this emergency alerts will be fitted into the vehicle Electrical and Electronics (E/E) architecture and will have interfaces with crash sensor network, CAN network and GSM etc.

Occupant motion in a vehicle rollover accident is a function of many factors. Some important ones are vehicle kinematics, position of the occupant in the vehicle, occupant size, ground topology and restraint usage. The far side belted occupants are more vulnerable than the near side occupants in a rollover accident as they have more energy as a result of their trailing and higher side of the vehicle. This outcome is attributable to the inadequate safety performance of the conventional single loop; B-pillar mounted D-ring restraints. Roof crush tends to displace the vehicle's B-pillar, resulting in D-Ring displacement which causes slack in the lap portion of the restraint. This slack enables centrifugal loads to move the far side occupant further away from the vehicle's instantaneous point of rotation. In this scenario, the presence of any ejection portal can result in an occupant becoming partially or fully ejected.

Active control mainly comprises of three parts; sensor-detects the input disturbance, actuator -provide counter measures and control logic -processing of input disturbances and converting it into logical output. Lot of methods for active vibration control are available but this paper deals with active control of steering wheel vibrations of an LCV. A steering wheel is, one such component that directly transfers vibration to the driver. Active technique described here is implemented using accelerometer sensor, IMA (Inertial Mass Actuator) and feed forward Fx-LMS (Filtered reference Least Mean Square) control algorithm. IMA is a single-degree-of-freedom oscillator. To enable a control, IMA needs to be coupled to the structure at a single point, acting as an add-on to the passive system. Fx-LMS is a type of adaptive algorithm which is computationally simple and it also includes compensation for secondary path effects by using an estimate of the secondary path.