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An agricultural tractor is often modified for special farming applications such as horticulture where the standard design is not suitable or accessible. In such cases, farm equipment manufacturers are demanded frugal and cost effect Engineered farming solutions. One such design is the innovative High Ground Clearance Tractor (HGCT) kit offered to increase the Tractor height without damaging the crop during farming operations. In this paper, the author proposes a durability assessment method to evaluate the HGCT kit attachments to meet the durability criteria. Road load data acquisition is done to measure the acceleration and strain levels for various horticulture operations such as tillage, spraying and transportation. Actual operating conditions are simulated with the help of four poster durability setups inside the lab which helps to reduce the field testing for design iterations.

In the realm of modern powertrains, the paramount objectives of weight reduction, cost efficiency, and friction optimization drive innovation. By streamlining drive trains through component minimization, the paper introduces a groundbreaking approach: the integration of fuel pump and vacuum pump drive systems into the main camshaft of a two-valve-per-cylinder push-rod actuated 4-cylinder diesel engine. This innovation is poised to concurrently reduce overall weight, lower costs, and minimize drive losses. The proposed integration entails the extension of the camshaft with a tailored slot, accommodating a three-lobed cam composed of advanced materials. This novel camshaft configuration enables the unified propulsion of the oil pump, vacuum pump, fuel pump, and valve train, effectively consolidating functions and components.

The cost of fuels used for automobile are rising in India on account of high global crude oil prices. The fuel cost constitutes major portion of total cost of operation for Heavy commercial vehicles. Hence, the trend is to carry the goods transport through higher payload capacity rigid/straight trucks that offer lower transportation cost per unit of goods transported. This is driving the design of multi-axle heavy trucks that have lift axles. In addition, improved network of highways and road infrastructure is leading to increase in average operating speed of heavy commercial vehicles. It has made increased focus on occupant as well as road safety while designing the heavy trucks. Hence, the analysis of lift axle suspension from the point of view of vehicle handling and stability is essential. There are two basic kinds of lift axle designs used in heavy commercial vehicles: self-steered lift axle having single tire on each side and non-steered lift axle with dual tires on each side.

In automotive world role of suspension system is to absorb vibrations from the road, and to provide stability while vehicle is going over bumps or uneven roads, cornering, acceleration and braking etc. For body on frame SUVs which are typically characterized by high center of gravity, it is quite critical to find best balance in ensuring stability of the vehicle and having comfortable ride performance. Rigid axle rear suspension is quite a typical choice in such vehicles, wherein lower and upper control links are two important components subjected to lateral, longitudinal, and vertical loads. These links allow the vehicle to move smoothly throughout the entire range of suspension travel. Kinematics and compliance optimization of these links is a major factor in definition of ride-handling performance of the vehicle.

Increased popularity on SUV category in the market has led to high focus on performance attributes of SUVs. Considering high weight & CoG achieving target handling performance is always a challenge. Static Wheel Alignment parameters, especially Camber have shown significant contribution in Handling attributes of vehicle. This paper presents an experimental study on change in wheel camber under the influence of different vehicle loading conditions. In SUVs, generally wheel is subjected to large deflection from its high static loads which makes it quite difficult to maintain an ideal camber angle. Hence, it is important to analyze the camber angle variations under actual loading conditions. An in-house fixture is developed to emulate the actual vehicle loading conditions at rear wheel end. The multi-link rigid axle suspension with watt’s link assembly is mounted on the chassis-frame which is rigidly fixed to ground, and loads are achieved through hydraulic actuators at Wheels.

Regenerative braking is an effective approach for electric vehicles (EVs) to extend their driving range. To enhance the braking performances and regenerative energy, regenerative braking control strategy based on multi objective optimization is explained in this paper. This technical paper would be focusing on extracting optimum Range with effective brake performances without affecting drivability and performances in different drives modes. An extensive research study on public road driving patterns is done to understand the percentage utilization of brakes at various (low-mid-high) speeds as per the customer driving behavior. Multi-Objective optimization function with three vital factors is defined where output generated power, torque smoothness and current smoothness are selected as optimization objective to improve the driving range, braking comfort, and battery lifetime respectively.

The inherent capacity of electric motors to generate substantial instant torque can lead to significant load reversals in electric vehicle driveshafts under specific road conditions and driving maneuvers, highlighting the need for targeted improvements in driveshaft design, particularly in optimizing joint sizing. This paper presents a systematic approach to investigate the root causes of a catastrophic driveshaft failure that occurred during specific vehicle tests on a road with multiple speed bumps, resulting in numerous high torque reversals. The objective was to enhance system robustness through changes in driveshaft design and the manufacturing process, coupled with a software calibration technique to reduce torque demands under such operating conditions. The process encompassed torque measurements at the vehicle level, failure replication on a test rig, and correlation with simulations.

Precise control over mixture formation withhigh fuel pressure and multiple injections allows Gasoline Direct Injection (GDI) engines to be operated satisfactorily at extreme conditions wherePort Fuel Injection (PFI) engines wouldnormally struggle due to combustion instability issues. Catalyst heating phase is one such important condition which is initiated after a cold engine start to improve the effectiveness of the three-way catalyst (TWC). For a given TWC specification, fast light-offof TWC is achieved in the catalyst heating phase by increasing the exhaust gas temperature with higher exhaust mass flow. The duration of this phase must be as short as possible, as it is a trade-off between achieving sufficient TWC light off performance and fuel efficiency.

Automotive steel wheel is a critical component for human safety. For validating steel wheel various tests will be performed at component and vehicle level. Cornering test performed at vehicle level is one of the tests, where wheel will be validated for high cornering loads. Cornering test performed at vehicle level consists of three different events i.e., rotations of vehicle in track1, rotations of vehicle track 2 and rotations of vehicle in track3. As wheel will experience different loading in each of the events of cornering test, correlating the virtual Finite Element Analysis (FEA) with physical test is quite challenging. If in FEA we can predict the damage and life very near to the physical validation, we can create a safe wheel for high cornering loads without any test concerns. Vent hole shape and Hat depth are two important aspects in wheel disc design. Vent hole shape and size will influence the heat dissipation of braking.

Wheel rim is one of the most critical safety parts in a vehicle. Strength in cornering loading is one of the most important durability test requirements for automotive steel wheel rim apart from other loading conditions like vertical and impact loads. Based on the category of vehicle and customer usage pattern, the accelerated cornering test is derived for testing steel wheel rims. The simulation and certification of steel wheel rim for the required dynamic durability testing requirement involves many steps ranging from acceptance criteria derivation to reliably addressing known potential failure zones in steel wheel rims. Nave radius and crown are sensitive to cornering loads, given the pitch circle diameter at the concept stage, the known effects of these key parameters are determined from DOE and used as reliable indicators to arrive at the shape and section of the steel wheel rim.

In the automobile industry, the door closing effort spells out the engineering and quality of the vehicle. After the visual impact a vehicle has on the customer, the doors are most likely the very first part of the vehicle he/she encounters, to enter and exit the vehicle. One of the customer’s very first impressions about the quality of the car is given by the behavior of the doors when opening and closing, the swinging velocity and the energy that is required to obtain a full latching that the door makes when closed by the user. Door closing effort gives an indication of how good or bad the vehicle is engineered. The purpose of this paper is to propose modifications in the door system which help in reduction of door closing effort or velocity by two different methods, EZ Slam Door and Bungee Rope. In this paper, parameters like hinge friction, hinge axis inclination, sealing, latch and air bind effect are analyzed which affect door closing effort.

Use of Computer Aided Engineering (CAE) tools for virtual validation has become an essential part of every product development process. Using CAE tools, accurate prediction of potential failure locations is possible even before building the proto. This paper presents a detailed case study of virtual validation of Backhoe Loader (BHL) dipper arm using CAE tools (MBD: Multi Body Dynamics and FEA: Finite Element Analysis) and comparison of simulation results with test data. In this paper, we have illustrated the modelling of Backhoe Loader in MSc ADAMS software. The detail ADAMS model was created and validated. The component mass, Center of Gravity (C.G) and Mass Moment of Inertia (MOI) was taken from CAD data. Trenching is simulated by operating the different hydraulic cylinders of the BHL. Loader arm cylinders and stabilizer cylinders are operated to lift the machine tires above the ground level.

Today’s automotive industry is a highly competitive market where continuous innovation in design and production of vehicles is required to gain market share and survive in the market. This led to reduction in the life cycle of the design process and design tools. Identifying, understanding and refining these details is significant to develop sustainable cars. Body and chassis stiffness are important specifications of a passenger car which affects handling, steering and ride characteristics of the vehicle. It has been proved that torsional, lateral and local chassis stiffness can play a role in giving the customer a premium feeling by affecting key metrics in the vehicle dynamics behaviour of a passenger car. In this paper, the effect of chassis stiffness on vehicle dynamics performance is studied using computer aided engineering (CAE). Different attributes of vehicle dynamics like vehicle handling, On-Center feel and vehicle ride are considered as performance characteristics.

The 48V mild-Hybrid system uses a 48V Lithium - Ion battery pack to boost the engine performance, to harness recuperative energy and to supply the accessory boardnet power requirement. Thermal management of the 48V battery pack is critical for its optimal utilization to realize the mild hybrid functionality, to meet CO2 reduction targets and useful life particularly under usage in hot ambient conditions. This paper discusses the various challenges and options of thermal management for the 48V battery pack based on the usage pattern and environmental conditions. The lifetime for a passively cooled battery pack is estimated for a typical Indian usage pattern. Active-air cooling is evaluated for the thermal management of the 48V mild-Hybrid battery pack. The tradeoffs are compared in terms of availability of hybrid functions and battery life.

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.

A vehicle drifts due to several reasons from its intended straight path even in the case of no steering input. Vehicle pull is a condition where the driver must apply a constant correction torque to the steering wheel to maintain a straight-line course of the vehicle. This paper presents an investigation study into the characteristics of a vehicle experiencing steering drift. The aim of the work is to study vehicle stability and the causes of vehicle drift/pull during straight line to minimize vehicle pull level and hence optimize safety measures. A wobble in the steering wheel feels like the steering wheel is shaking to the left and right. This may get worse, if speed increases. This paper focuses on modelling and evaluating effects of suspension parameters, differential friction, brake drag variation, Unbalanced mass in the wheel assembly and C.G. location of the vehicle under multibody dynamic simulation environment.

Drive cycles have been an integral part of emission tests and virtual simulations for decades. A drive cycle is a representation of running behavior of a typical vehicle, involving the drive pattern, road characteristics and traffic characteristics. Drive cycles are typically used to assess vehicle performance parameters, perform system sizing and perform accelerated testing on a test bed or a virtual test environment, hence reducing the expenses on road tests. This study is an attempt to design a relatively robust process to generate a real world drive cycle. It is based on a Six Sigma design approach which utilizes data acquired from real world road trials. It explicitly describes the process of generating a drive cycle which closely represents the real world road drive scenario. The study also focuses on validation of the process by simulation and statistical analysis.

Traffic awareness of the driver is one of the prime focus in terms of pedestrian and road safety. Driver experience plays a significant role and driving requires careful attention to changing environments both within and outside the vehicle. Any lapse in driver attention from the primary task of driving could potentially lead to an accident. It is observed that, lack of attention on the ongoing traffic and ignorant about the traffic information such as traffic lights, road signs, traffic rules and regulations are major cause for the vehicle crash. Traffic signals & signage are the most appropriate choice of traffic control for the intersection, it is important to ensure that driver can see the information far away from the intersection so that he/she can stop safely upon viewing the yellow and red display. Then, upon viewing the signal operations and conditions the motorist can stop his/her vehicle successfully before entering the intersection.

The traditional approach of engine thermal behavior of engine during startup has largely been dependent on experimental studies and high fidelity simulations like CFD. However, these techniques require considerable effort, cost and time. The low fidelity simulations validated with experimental results are becoming more popular due to their ease in handling the several parameters such as cost effectiveness and quick predictive results. A four point mass model of engine thermal behavior during cold start has been developed to study the engine warm up temperature behavior. The four point mass model considers the lumped mass of coolant, mass of engine directly associated with the coolant, mass of engine oil and mass of engine directly associated with the engine oil. The advantage of four point model is to predict the coolant temperature as well as lubricant temperature during the transient warm up cycle of the engine.

The effort involved in automotive software test/calibration at road level is very high and cost involved is also commendable because of the involved proto level samples. Further the on-road test/calibration process is sensitive to external factors like drive pattern and environmental conditions. It is always a challenge for any OEM, to come up with an efficient process, which optimizes development cost, time and reliability of the product. The model based test/calibration process is always a dream for any engineer to work on, as it has big advantage of cost, reproducibility and repeatability of test cases [1]. But the challenge lies in achieving the closeness to reality with limited availability of crucial data for model parameterization. Activity at test bed level bridges the gap between the on-road and model based test/calibration achieving high maturity level at optimal cost/time. Current vehicle has many systems, which work in synergy to create an impact on end customer.