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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.

In high speed race cars, aerodynamics is an important aspect for determining performance and stability of vehicle. It is mainly influenced by front and rear wings. Active aerodynamics consist of any type of movable wing element that change their position based on operating conditions of the vehicle to have better performance and handling. In this work, front and rear wings are designed for race car prototype of race car. The high down force aerofoil profiles have been used for design of front and rear wing. The first aerodynamic analysis has been performed on baseline model without wings using CFD tool. For investigation, parameters considered are angle of attack in the range of 0-18° for front as well as rear wing at different test speeds of 60, 80, 100 and 120 kmph. The simulation is carried out by using ANSYS Fluent. The simulation results show significant improvement in vehicle performance and handling parameters.

Active aerodynamics can be defined as the concept of reducing drag by making real-time changes to certain devices such that it modifies the airflow around a vehicle. Using such devices also have the added advantages of improving ergonomics and performance along with aesthetics. A significant reduction in fuel consumption can also be seen when using such devices. The objective of this work is to reduce drag acting on a passenger car using the concept of active aerodynamics with grill shutters and air dams. First, analysis has been carried out on a baseline passenger car and further simulated using active grill shutters and air dams for vehicle speed ranging from 60 kmph to 120 kmph, with each active device open from 0° to 90°. The optimized model is then validated for a scaled down prototype in a wind tunnel at 80kmph. Vehicle has been modelled using SolidWorks tool and the simulation has been carried out using ANSYS Fluent.

Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.

Hyperelastic material simulations are commonly performed in commercial FE codes due to availability of sophisticated algorithms facilitating virtual characterization of such materials in FEA easily. However, the solution time required is longer in FEA. Especially when excitation frequencies do not interfere with structural modes, flexible multibody simulation offers a lucrative and computationally inexpensive alternative. However, it is difficult to directly characterize hyperelastic materials in commercial MBS simulation codes, so the reduced solution time comes at the cost of decreased simulation accuracy, especially if the designer is provided with crude stress - strain test data. Hence, the need is to overcome the drawbacks in FEA and multibody codes, as well as to leverage best of both these codes simultaneously.

An open wheeled open cockpit high speed car with 800 CC MPFI engine was developed validated and run at 105 kmph. The key focus was to build a car with superior aerodynamic characteristics especially in terms of drag. This work discusses in detail about the design and simulation of car using CFD package followed by Wind Tunnel testing. The design of high speed car starts with design of seat according to the ergonomics of the driver followed by the space frame. Based on the space frame designed, the body panels are sketched and CAD model is developed. The CAD model is imported in CFD package for virtual testing and validated through wind tunnel results. For this 1:3 scale model was manufactured using Rapid Prototyping.

This work is a part of program on “Development of High Performance DI, 3 Cylinder CRDI Diesel Engine to meet Euro-IV/V Emission Norms focused on automotive passenger car application purpose. This is a 3 Cylinder, TCIC engine designed for combustion pressure of 160 bar max for first stage which is being upgraded to 200 bar max in the second stage. Cylinder Head design is a part of complicated configuration whose construction and principal dimensions are dependent on the size of inlet and exhaust valves, fuel injectors positioning and mounting, port layout and swirl and shape of combustion chambers. The cylinder head of a direct-injection diesel engine has to perform many functions. It has to bring charge air to the cylinder and exhaust gas from the cylinder, with minimum pumping loss and required swirl and other properties of charge motion.

In year 2015, 17 people were killed every hour by road accidents in India [1]. The occurrence of road accidents is observed to be higher during night, when visibility is at its lowest. The two factors which affect visibility are insufficient illumination and glare caused by the oncoming traffic. The Adaptive Front Lighting System [AFS] is an active safety feature which addresses these problems by employing specific lighting modes for Town, Country, Expressway conditions and automatic switching between Driving Beam and Passing Beam whenever required. Matrix of LEDs or a Projector with an actuator or a combination of both is employed in achieving different Lighting modes. The projector based AFS module is preferred for implementing the AFS control logic for passing beam owing to its economic cost.

Frontal crash is the most common type of accidents in passenger vehicles which results in severe injuries or fatalities. During frontal crash, some frontal vehicle body has plastic deformation and absorbs impact energy. Hence vehicle crashworthiness is important consideration for safety aspect. The crash box is one of the most important parts in vehicle frontal structure assembly which absorb crash energy during impact. In case of frontal crash accident, crash box is expected to be collapsed by absorbing crash energy prior to the other parts so that the damage to the main cabin frame and occupant injury can be minimized. The main objective of this work is to design and optimize the crash box of passenger vehicle to enhance energy absorption. The modeling of the crash box is done in CATIA V5 and simulations are carried out by using ANSYS. The results show significant improvement in the energy absorption with new design of the crash box and it is validated experimentally on UTM.

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.

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.

Gerotor pump is a positive displacement pump unit which is widely used for lubrication in on-road and off-road engine applications. This paper is focused on Gerotor pump design competency established at ARAI comprising of design of inner and outer rotors, suction & delivery ports, optimizing inlet and outlet diameters & its position, development of methodology to calculate oil flow rate, volumetric efficiency, mechanical efficiency & slippage. The finalization of design is followed by CFD of Gerotor pump to optimize the pressure and flow pulsation. A trochoidal profile is used to design the inner and outer rotors and its conjugate profile are realized by a set of equations using a method based on the theory of gearing. Suction and delivery port is analytically designed based on the same design parameters of the trochoidal profile.

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.

Tire failure is identified as a major cause of accidents on highways around the world in the recent past. A tire burst leads to loss of control of the vehicle which ends up in a catastrophe. There are various factors which are accounted for a tire burst. Heat buildup, aging of tire and cracks on tires are the major ones which are identified. A superior ability of the tire to dissipate the heat generated during operation is a major factor which prevents a tire failure. Other factors such as ambient temperature, inflation pressure etc. contributes to heat buildup which may ultimately result in tire failure. A combination of these factors might manifest as a tire failure at high speeds, the latter being an immediate cause of heat buildup. A dormant crack in the tire might develop if the temperature and pressure conditions are favorable, thus giving away at the weakest point. With regard to the temperature conditions, road conditions, inflation pressure checks etc.

To enhance the crashworthiness of electric vehicles, designing the optimized and safer battery pack is very essential. The deformed battery cell can result in catastrophic events like thermal runaway and thus it becomes crucial to study the mechanical response of battery cell. The goal of the research is to experimentally investigate the effect of mechanical deformation on Lithium-ion battery cell. The paper thoroughly studies the phenomenon of short circuiting at the time of failure. Various experiments are carried on 18650 cylindrical cells (NCA chemistry) under custom designed fume hood. The setup captures the failure modes of battery cell. The loading conditions have been designed considering the very possible physical conditions during crash event. The study has been done for radial compression, semicircular indentation, hemispherical indentation, flat circular indentation and case of three-point bending.

Autonomous Emergency Braking (AEB) systems play a critical role in ensuring vehicle safety by detecting potential rear-end collisions and automatically applying brakes to mitigate or prevent accidents. This paper focuses on establishing a framework for the Verification & Validation (V&V) of Advanced Driver Assistance Systems (ADAS) by testing & verifying the functionality of a RADAR-based AEB ECU. A comprehensive V&V approach was adopted, incorporating both virtual and physical testing. For virtual testing, closed-loop Hardware-in-Loop (HIL) simulation technique was employed. The AEB ECU was interfaced with the real-time hardware via CAN. Data for the relevant target such as the target position, velocity etc. was calculated using an ideal RADAR sensor model running on the real-time hardware. The methodology involved conducting a series of test scenarios, including various driving speeds, obstacle types, and braking distances.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.

On-board diagnostics (OBD) is a term referring to a vehicle's self-diagnostic and reporting capability. It is a system originally designed to reduce emissions by monitoring the performance of major emission related components. There are two kinds of on-board diagnostic systems: OBD-I and OBD-II. In India OBD I was implemented from April 2010 for BS IV vehicles. OBD II was implemented from April 2013 for BS IV vehicles. Apart from the comprehensive component monitors, OBD II system also has noncontinuous monitors like Catalyst monitoring, Lambda monitoring, and other after treatment system monitors. For OBD II verification and Validation, it is required to test all the sensors and actuators that are present in the engine, for all possible failures. From an emissions point of view there are lists of critical failures that are caused due to malfunction of sensors and actuators. Carrying out the full matrix failure testing on the running engine could be tedious, unsafe and time consuming.

Design of vehicle for targeted customer usage is one of the key steps during vehicle development process. Due to globalization, most of vehicles, aggregates, components are being designed for global market considering worldwide load spectrum. Generally for doing this the vehicle response is being measured for different markets but this process is very time consuming. Also for getting these vehicle dependent parameters, exercises need to be repeated on each type/class of vehicle. So there is a need to have a robust procedure, tools which will helps OEM’s to predict the loads, vehicle response for different market segments at an early stage of vehicle development program using the inputs which are vehicle independent. The solution for this could be to use vehicle independent input such as digitized road profiles (2D or 3D) of target customer markets in combination with proper MBD simulation tools.

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.