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Accurate ride and handling prediction is an important requirement in today's automobile industry. To achieve the same, it is imperative to have a good estimation of damper model. Conventional methods used for modelling complex vehicle components (like bushings and dampers) are often inadequate to represent behaviour over wide frequency ranges and/or different amplitudes. This is difficult in the part of OEMs to model the physics-based model as the damper’s geometry, material and characteristics property is proprietary to part manufacturer. This is also usually difficult to obtain as a typical data acquisition exercise takes lots of time, cost, and effort. This paper aims to address this problem by predicting the damper force accurately at different velocity/ frequency and amplitude of measured data using Artificial Neural Networks (ANN).

Lubrication system is a critical factor for engine health. But it creates parasitic load and increased fuel consumption of the engine. The oil demand of an engine depends on engine speed, load, bearing clearances, operating temperature and engine's state of wear. Ideally, the oil pump should adapt the delivery volume flow to actual engine oil demand and should avoid unnecessary pumping of oil which causes increased power and fuel consumption. However in a conventional mechanical oil pump, there is no control on the oil flow and it is purely a function of operating speed. A variable discharge oil pump (VDOP) is an approach to reduce the parasitic losses wherein the oil flow is regulated based on the mechanical needs of the engine. This study is based on the results of a two stage VDOP installed on a 1.2 litre, 3 cylinder MPFI engine. The oil supply is regulated by a solenoid control which receives command from Engine Control Unit (ECU). The study was done in two stages.

Ride is essentially the outcome of coupled dynamics of various involved sub-systems which make it too complex to deal analytically. Tires, amongst these, are known to be highly nonlinear compliant systems. Selection of tires specifications such as rated tyre pressure, etc. are generally decided through subjective assessment. While experts agree that tyre pressure affects the attributes such as ride to a noticeable degree, the quantification of the change often remains missing. In the current work, vibration levels of various sub-systems relevant to ride in an SUV are measured for three different tyre pressures at different speeds over the three randomly generated roads. For the purpose, artificial road profiles of classes A, B and C are synthesized from the spectrum of road classes defined in ISO 8608:2016 and reproduced on a four-poster test rig.

This paper presents a comprehensive model of a hydraulic power steering system for predicting the transient responses under various steering inputs. The hydraulic system model, which integrates together all fluid line elements and hydraulic components, is formulated using the MSC Easy5 software. A full vehicle model is developed in ADAMS/Car. Functional Mock up Interface (FMI), a tool independent standard is used for co-simulation of ADAMS and Easy5 Dynamic models. This paper describes a co-simulation methodology developed using FMI interface for full vehicle Simulations using hydraulic power steering. A virtual simulation scheme is developed to obtain the system transient responses and the results are compared with those measured from the tests. In general, the simulation results agree with those obtained from the tests under the same steering inputs and operating conditions.

Steering returnability while driving is one of the most important parameter which affects the drive pleasure and handling of a vehicle. Steering returnability refers to the automatic returning response of the steering wheel after taking a full turn while vehicle is being steered during driving. Evaluating steering response characteristics of any vehicle in a virtual environment at early stage of a product development saves significant development time and cost. Through this paper an attempt has been made to develop a methodology for selection of suspension hard points which influences steering returnability characteristics of a vehicle at an early product design stage. Conventionally, suspension kinematic parameters such as Caster angle, Steering axis inclination (SAI), etc. are iterated during vehicle design stage to achieve desired Steering returnability.

Ride is an important attribute which must be accounted in the passenger segment vehicles. Excessive H point acceleration, Steering wheel acceleration, Pitch acceleration can reduce the comfort of the driver and the passengers during high frequency and low frequency rough road events. Excessive Understeer gradient, roll gradient, roll acceleration and Sprung mass lift could affect the Vehicle driver interaction during Steady state cornering, Braking and Step steer events. The concept architecture of the vehicle plays an important role in how comfort the vehicle will be. This paper discusses how to improve SUV ride performances by keeping handling performance attributes same or better than base vehicle. Multi Objective Optimization was carried out by keeping spring, bushing and damper characteristic as the design variables to avoid new system or component development time and cost.

The automotive industries around the world is undergoing massive transformation towards identifying technological capabilities to improve vehicle performance. In this regard, the engine dynamic torque plays a crucial role in defining the transient performance and drivability of a vehicle. Moreover, the dynamic torque is used as a visualization parameter in performance prediction of a vehicle to set the right engineering targets and to assess the engine potential. Hence, an accurate measurement and prediction of the engine dynamic torque is required. However, there are very few methodologies available to measure the engine dynamic torque with reasonable accuracy and minimum efforts. The measurement of engine brake torque using a torque transducer is one of the potential methods. However, it requires a lot of effort and time to instrument the vehicle. It is also possible to back-calculate the engine torque based on fuel injection quantity and other known engine parameters.

Current high rating thermal loaded engines must have super-efficient lubrication system to provide clean oil at appropriate pressure and appropriate lube oil temperature to every part of the engine at all engine RPM speeds and loads. So oil pump not only have to satisfy above parameters but also it should be durable till engine life. Gerotor pumps are internal rotary positive-displacement pumps in which the outer rotor has one tooth more than the inner rotor. The gear profiles have a cycloidal shape. Both are meshed in conjugate to each other. Gerotor takes up engine power through crankshaft and deliver to various engine consumers at required pressure and required time. Over the complete engine rpm speed and loads range, oil pump need to perform efficiently to provide proper functioning of the engine. Otherwise low oil pressure leads to more friction in the pump, seizure of bearings and final failure of the engine .High oil pressure can lead to failure in oil filter, gaskets and seal.

This study introduces a method to examine the flow path of the lubricant inside a transmission housing of a tractor. A typical gearbox has several loads bearing elements which are in relative sliding motion to each other which causes heat to be released. The major sources of friction as well as heat are the meshing teeth between gears (sun/planet, planet/ring & power/range drive gear), thrust washers, thrust bearings and needle roller bearings. The churning of oil performs the vital function of both lubricating these sliding interfaces and cooling these sources of heat, thereby preventing failure of the gearbox. In this paper, we have applied VOF multiphase flow model and sliding meshing to simulate the fluid flow during splashed lubrication within a mating gear box. Lubrication oil dynamics and oil surface interaction with the air is modeled using VOF multiphase approach.

Tractor weight transfer is the most common farm-related cause of fatalities nowadays. As in India it is getting mandatory for all safety devices across all HP ranges. Considering any changes in the weight from an attachment such as Rops, PTO device, tow hook and draw bar etc. can shift the center of gravity towards the weight. center of gravity is higher on a tractor because the tractor needs to be higher in order to complete operations over crops and rough terrain. Terrains, attachments, weights, and speeds can change the tractor’s resistance to turning over. This center of gravity placement disperses the weight so that 30 percent of the tractor’s weight is on the front axle and 70 percent is on the rear axle for two-wheel drive propelled tractors and it must remain within the tractor’s stability baseline for the tractor to remain in an upright position.

Side Door closing velocity is one of the key customer touch points which depicts the build quality of the vehicle. Side door closing velocity results from the interaction of different parts like door and body seals, door check arm, door hinge, latch, and alignment of door hinge axis. In this paper, a high door closing velocity issue in a sports utility vehicle is discussed. Physical studies are carried out to understand each parameter in door closing velocity and its contribution is defined in terms of velocity. Many physical trials are conducted to conclude the contribution of each parameter. Studies revealed that the body and door seal are contributing around 70% of door closing velocity. Check arm and hinge axis deviation are contributing around 10% of the door closing velocity. Physical trials are conducted by reducing the compression distance of the body seal.

A four-wheeled automobile during braking event in which left and right wheels of the vehicle are on different mu surfaces, has high chances of experiencing spin, which may lead to stability issues on vehicle. This paper intends to provide a mathematical approach to predict the deceleration at which vehicle will spin during braking in a differential mu surface, and determine the effect of influencing parameters on the extent of the vehicle spin tendency. This paper also provides a correlation between theoretical vs actual decelerations for vehicles to exhibit vehicle spin tendency. This paper helps in providing sufficient aid/tool for system designer to predetermine the vehicle spin at early level of system designs and make necessary amendments at initial stage of prototype development rather than late changes, to create a product which gives safe driving experience.

Hardware-in-the-loop (HIL) test benches are indispensable for the development of modern vehicle dynamics controllers (VDCs). They can be regarded as a standard methodology today, because of the extremely safety critical nature of the multi-sensor and multi-actuator systems used in vehicle dynamics control. The required high quality standards can only be ensured by systematic testing within a virtual HIL environment before going into a real car. The steering system is an important aspect of the automobile from operational safety and driver enjoyment perspectives. Current Problem/Opportunity is realistic subjective steering feel prediction before vehicle build. And upfront predict the handling characteristics more accurately with subjective feel before proto build. Current Issue is difficult to convert the objective data into subjective feel and difficult to incorporate the nonlinear steering characteristics with hysterics, friction and power assist curves using virtual simulation.

This paper is an attempt to compile a systematic approach which can be easily incorporated in the product development system used in the design and development of parking brake systems for passenger cars having rear drum brakes, which in turn can effectively reduce the lead time and give improved performance. The vehicle GVW, percentage gradient and maximum effort limits (as per IS 11852 - Part 3), tire and drum brake specifications were taken as front loading. This data is used for target setting of functional and engineering parameters, such as lever pull effort, lever ratio and angular travel of lever. Design calculations were performed to obtain theoretical values of critical parameters like lever effort and travel. The comparison between target and theoretical values give the initial confidence to the system engineer. Further, the outcome was taken to conceptualize the hard points of lever on vehicle for ergonomics.