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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.

Major cause of air pollution in the world is due to burning of fossil fuels for transport application; around 23% GHG emissions are produced due to transport sector. Likewise, the major cause of air pollution in Indian cities is also due to transport sector. Marginal improvement in the fuel economy provide profound impact on surrounding air quality and lightweighting of vehicle mass is the key factor in improving fuel economy. The paper describes robust and integrated approach used for design and development of lightweight bus structures for Indian city bus applications. An attempt is made to demonstrate the use of environment friendly material like aluminium in development of lightweight superstrutured city buses for India. Exercise involved design, development and prototype manufacturing of 12m Low Entry and 12m Semi Low Floor (SLF) bus models.

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.

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.

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.

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.

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.

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.

Nickel electroplating is commonly used with substrates including steel, aluminum, plastic and zinc die-cast parts because of its high resistance to temperature, corrosion and wear in harsh conditions. To further enhance its tribological and mechanical properties, research works are going on to produce nano-reinforced composites of Ni with various ceramic and rare earth oxides like CeO2, ZrSiO4, SiC, TiO2, etc. The aim of present work is synthesis and characterization of Ni films and Ni based TiO2 nano-composite coating processed by pulse co-electrodeposition technique. Also, to investigate the various properties such as mechanical, wear and corrosion resistance, conductivity & thermal stability of Ni-TiO2 nanocomposites electrodeposited on steel substrate, especially the effects of the amount of nanosized TiO2 particles in Ni-TiO2 nanocomposites.

Utilization of higher ethanol blends, 20% ethanol in gasoline (E20), as an alternate fuel can provide apparent benefits like higher octane number leading to improved anti-knocking properties, higher oxygen content resulting in complete combustion. Apart from technical benefits, use of ethanol blends offer certain widespread socioeconomic benefits including option of renewable source of energy, value addition to agriculture feedstock resulting in increase in farm income, creation of more jobs in rural sector and creating job at local levels. Use of higher blends of ethanol can reduce dependence on foreign crude leading to substantial savings in cost of petroleum import. The impact of higher Gasoline-Ethanol blend (E20), on the fuel system components of gasoline vehicles must be known for assessment of whether the fuel system will be able to perform as intended for the complete design life of the system.