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Hydrogen Internal Combustion Engine (H2ICE) has hydrogen gas storage system and is operated at very low temperature before it enters the combustion chamber. The effect of hydrogen on steel materials is detrimental because of hydrogen embrittlement. Forged steel parts are used in engine specifically valve. The goal of the work is to analyze the outcome of low temperature i.e. 35 °C to -30 °C on three types of forged steel materials i.e. 40Cr4, 42CrMo4 and EN8 and assess any potential changes in their properties due to ductile to brittle transition. Charpy impact test is widely used to determine the temperature at which a material shifts from exhibiting ductile behavior to brittle behavior. This transition is critical for understanding the safety and reliability of steel components, as brittle fracture can lead to catastrophic failures.

India is one of the largest markets for the automobile sector and considering the trends of road fatalities and injuries related to road accidents, it is pertinent to continuously review the safety regulations and introduce standards which promise enhanced safety. With this objective, various Advanced Driver Assistance Systems (ADAS) regulations are proposed to be introduced in the Indian market. ADAS such as, Anti-lock Braking Systems, Advanced Emergency Braking systems, Lane Departure Warning Systems, Auto Lane Correction Systems, Driver Drowsiness Monitoring Systems, etc., assist the driver during driving. They tend to reduce road accidents and related fatalities by their advanced and artificial intelligent fed programs. This paper will share an insight on the past, recent trends and the upcoming developments in the regulation domain with respect to safety.

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.

FEA based simulations are extensively used in automotive industry for improving the product design and reducing the time taken for design and prototyping. FEA based simulations require material data as an input in form of material models. Most commonly used material models for simulation of metallic materials are elastic models and elasto-plastic models, which provide very good correlation till ultimate tensile strength (UTS). For simulation beyond UTS value, elasto-plastic material model has to be used along with material model considering the damage accumulation post UTS. For crash like event in automotive crash, required material models should consider the effect of various stress state conditions (Triaxiality) and strain rate sensitivity of materials along with damage accumulation. In LS Dyna solver, MAT_ADD_EROSION material model (GISSMO) along with MAT_024 is widely used for these applications.

In present scenario, tyre industry is more focused on providing maximum extent of NVH comfort to passengers by improvising the tyre design. Noise contribution from the tyres is classified in to three regions, viz., structure-borne (tyre vibrations), air-borne (tread pattern) and cavity noise (air cavity). In general, a Finite Element (FE) model of tyre provides an inherent advantage of analyzing tyre dynamic behavior. In this paper, an attempt was made to develop a three-dimensional FE tyre model and validate the same through experimental approach. The CAD Model of the tyre was generated through 3D image scanning process. Material property extraction of tyre was carried out by Universal Testing Machine (UTM) to generate Finite Element (FE) model. For validation of tyre FE model, Experimental Modal Analysis (EMA) and Noise Transfer Function (NTF) were conducted.

An excellent physical and mechanical property makes Aluminium (Al) alloy suitable alternative lightweight materials against steel and cast iron in automotive components. ICME is a computational tool, which integrates the materials information to engineering product performance analysis. MatCalc is ICME tool, which follows the chain rule of process, microstructure, property and performance relationship in materials development. This paper reports the development of Al 6061-T6 propeller shaft through forging process and the materials and process model of the Al yoke is simulated using MatCalc simulation software. Finite element analysis method is used for designing of Al 6061-T6 propeller shaft. The forged Al yoke is solutionized at temperature 550°C for 1 hr followed by artificial ageing at temperature 180°C for 16 hrs to improve the hardness and strength of the yoke.

In order to travel in a chaotic and dynamic environment, an autonomous vehicle requires a motion plan. This motion plan ensures collision free, optimum travel without violating any traffic rules. The optimum solution for path planning problem exists in higher dimensions, however, with the help of useful heuristics the problem can be solved in real time, which is required for real time operation of an autonomous vehicle. There are different well established techniques available to plan a collision free kinematically traversable path. One of such techniques is called conformal Lattice planner. However, the legacy version of conformal lattice planner is not optimized and also is prone to fail under specific dynamic environment conditions. Moreover, the legacy version of conformal lattice planner is also not road aware. Due to this reason it is a semi optimized way to solve the motion planning problem.

Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing arrangements. Based on benchmarking, a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing- at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption of a bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.

Electric passenger car with floor battery usually have its front boot space empty and the space is used as additional luggage storage. This space can be utilized to capture the wind energy and generate electricity. Based on this, the objective of this work is to perform an aerodynamic analysis of an electric passenger car using wind turbine placed at the front. Initially the aerodynamic analysis of a basic electric car model is performed and further simulated using wind turbines and aerodynamic add-on-devices. The simulation is carried-out using ANSYS Fluent tool. Based on the simulation result, scaled down optimized model is fabricated and tested in wind tunnel for validation. The result shows reduction of drag coefficient by 5.9%.

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.

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.

In today’s scenario, the emission norms are getting stringent day by day due to an increased level of pollution. The world is shifting towards low carbon footprint which made it necessary to adopt efficient technologies with fewer emissions. The hybridization of vehicles has resulted in improved efficiency with lower emissions which can fulfil the near future emission norms. Retrofitting of hybrid components into a conventional IC engine vehicle is so far the best way to achieve better performance both economically and technologically. This research is primarily focused on the design and development of a novel retrofit solution of P3x architecture for the light commercial vehicle. This retrofit solution is different from other hybrid solutions in terms of powertrain. It contains an innovative add-on powertrain along with the existing powertrain. This additional powertrain consists of a pair of helical gears followed by a chain and sprocket as a coupler for traction motor.

Any change is vehicle exterior design, affects the aerodynamics characteristic. Generally different types of roof racks are attached on passenger vehicles to carry luggage which affects aerodynamic drag. The objective of this work is to perform aerodynamic analysis of ground vehicle with roof rack to investigate the change in drag coefficient. First, the aerodynamic analysis of a baseline passenger car model is performed with and without generic benchmarked roof rack at 100 kmph. Further analysis is carried out with different new designs of roof racks. Based on simulation result, a scaled down prototype model is fabricated and validated by using a wind tunnel test for optimum suitable case. The modelling of the vehicle is done in CATIA tool and simulation is carried out by using ANSYS Fluent.

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.

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.

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.

Air suspension systems had been introduced in automobiles since 1950s. These systems are being explored to improve the ride comfort, handling stability and also serve as a medium for better cargo protection. These system are well developed for buses and high end passenger sedans, also have feasibility for adapting for wide range of configurations of suspension system and axle. Passenger cars and Sports Utility Vehicle (SUV) pickup category of vehicle offers different challenges such as space availability, spring selection and characterization that need to be addressed for successful implementation of air suspension in these category vehicles. This work defines methodology to implement air suspension system in SUV Pickup category vehicle. Paper work includes concept study, mathematical co-relation, and prediction of air spring characteristics and integration of experimental and analytical tool for development of air suspension system.

The Steering system is one of the most safety critical systems in an automobile. With time the durability, reliability and the fine-tuning of the parameters involved in this subsystem have increased along with the competitiveness of the market. In a competitive market, accelerated testing is the key to shorter development cycles. It is observed that the majority of component manufacturers have a preference on vehicle level testing to achieve their development goals. The vehicle level trials are time consuming and lack the control and repeat-ability of a laboratory environment. This paper describes the development of a steering test rig designed to simulate the disturbances experienced on road within a controlled laboratory environment. The five axis steering rig would allow simulation of individual road wheel displacement along with steering wheel angle input and lateral steering rack displacements. The rig also is designed to be adaptable to a range of vehicle categories.

Front windscreen wiping test is legal requirement for all motor vehicles as per standards like IS15802:2008 [1], IS15804:2008 [2] in India. This test requires windscreen mock-up/actual vehicle to be tested along with all wiping mechanisms such that minimum percentage areas to be wiped should meet the requirements specified in the IS standard. From manufacturer’s perspective this involves investment of lot of time and cost to arrive at the final design solution in order to meet the wiping requirements. The work scope in this paper is limited to bus category of vehicles. The methodology presented in this paper would enable quick design solutions for bus body builders or manufacturers to meet the wiping requirements specified in IS standard. The methodology presented in this paper was developed to carry out windscreen wiping test through commercially available simulation software.

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.