This seminar provides an introduction to the fundamental concepts and evolution of passenger car and light truck 4x4/all-wheel drive (AWD) systems including the nomenclature utilized to describe these systems. Basic power transfer unit and transfer case design parameters, component application to system function, the future of AWD systems, and emerging technologies that may enable future systems are covered. This course is an excellent follow-up to the 98024-A Familiarization of Drivetrain Components seminar (which is designed for those who have limited experience with the total drivetrain).
Active Safety, Advanced Driver Assistance Systems (ADAS) are now being introduced to the marketplace as they serve as key enablers for anticipated autonomous driving systems. Automatic Emergency Braking (AEB) is one ADAS application which is either in the marketplace presently or under development as nearly all automakers have pledged to offer this technology by the year 2022. This one-day course is designed to provide an overview of the typical ADAS AEB system from multiple perspectives.
Fastener experts believe that upwards of 95% of all fastener failures are the result of either the wrong fastener for the job or improper installation. Whether this shocking figure is accurate or not, it is irrefutable that threaded fasteners are poorly misunderstood by many in both the fastener and user communities. In October 1990 the USS Iwo Jima suffered a catastrophic steam valve accident minutes after leaving port following repairs to its steam plant. In one of the single most deadly events of Operation Desert Storm, ten of the eleven crewmen present in the engine compartment would lose their lives.
OBJECTIVE Race vehicles are designed to achieve higher lateral acceleration arising at cornering conditions. A focused study on the steady state handling of the car is essential for the analysis of such conditions. The transient response analysis of the car is also equally important to achieve best driver-car relationship and to quantify handling in the range suitable for a racing car. This research aims to investigate the design parameters responsible for the transient characteristics and optimize those design parameters. This research work examines the time-based analysis of the problem to truly capture the non-linear dynamics. Apart from tires, chassis can be tuned to optimize vehicle handling and hence the response times. METHODOLOGY To start with, the system is modelled with governing parameters and simulation is carried out to set baseline configurations. Steady state and transient handling simulations run independent of each other with independent logic, coded on MATLAB.
Objective This paper explores the usage of Altair simulation driven optimisation process, Front Suspension hard points of a sedan Car model are optimised for specific target toe curves using MotionView, MotionSolve and HyperStudy This process gives the optimal hard point values to match the target curves without much iterations. Methodology Parametric Multibody model of the front end of sedan is built in MotionView. To Carry out optimisation HyperStudy is used where few of the suspension hard points which affect the toe curves are chosen as design variable. For the chosen Design variables upper and lower bound limits are specified. Ride, Roll and lateral force tests are performed. Optimisation is performed using HyperStudy where it iterates the suspension hard points to match the target toe curves. Each iteration response can be visualized in HyperStudy and can be compared with the target toe curve.
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 and the simulation has been carried out using ANSYS Fluent.
The study aims to evaluate the lateral stability of tractor-front end loader system in consideration with difficult work conditions based on various loader bucket lifting heights from ground while driving a system on transversal slopes. In the proposed method the centre of gravity of tractor-front end loader system was calculated and analysed to evaluate the transversal overturning of the system. This overturning of the system was analysed by applying mathematical equations presented in past studies and compared with the newly developed prediction model for 3 test tractors of 25 HP. The excel spreadsheet comprised of mathematical equations used to calculate the Tractor Stability Index (TSI) on transverse slope with respect to loader bucket height and payload in dynamic condition. A criterion has been defined to categorize the Tractor Stability Index (TSI) poor to excellent on a scale of 0 to 4 where <0 being the very poor, 0-2 Poor, 2-4 Good and >4 being the excellent.
Research Objective The importance of evaluating ride comfort with high degrees of accuracy objectively and its correlation with subjective perception is increasing day by day because of the long duration of the driving experience. The complex motion of the vehicle which is the combination of heave, roll and pitch motion is responsible for causing extreme uneasiness to the driver as well as the passenger. In this paper, ride comfort evaluation is done on the highway with similar traffic conditions with the help of Vibration Dose Value Analysis, Suspension Working Space and Ride Diagram methods for two hatchbacks and its correlation with the complex motion like choppiness of the vehicle is established that will help us to enhance the driver ride experience. Methodology The ride testing is performed for two hatchbacks on a highway road with different kinds of terrain ranging from highly uneven road roughness to moderately smooth surface for a speed range of 60-100 kmph.
In the current commercial vehicles market, ride-comfort and handling are crucial parameters for the customer and end user. There are various aspects which determine the vehicle behaviour. One of aspects is the structural rigidity of the vehicle, which has its own effect on vehicle dynamics. To meet the required stiffness of the main structural component of the vehicle i.e. chassis frame, FEA analysis has to be done in current methodology. The number of iterations have to be done to build an appropriate model with low weight, which can meet the design requirements. At first, conceptual design mock-up unit is to be developed then FEA (CAE) analysis to be done on it. If any design criteria are not met, then this cycle repeats again until it fulfils the required stiffness. Today, the direct stiffness procedure is the basic principle of almost every FEA software package.
Tyre Traction Trailer is a device designed to find the Peak Brake co-efficient of C2 and C3 tyre as per ECE R117. The trailer is towed by the truck and is braked suddenly to evaluate braking co-efficient of specimen tyre. It is a single wheel trailer equipped with load cell to capture tire loads (Normal and longitudinal)while braking. Traction Trailer is modelled in MSC Adams and rigid body simulation is carried out for static stability of the system. Dynamic simulations were performed to understand locking of wheels during braking. Body frame was further modelled as flex body to perform structural analysis of the frame. The paper contains stress and deformation plots of trailer Structure under various loading conditions, change in Centre of gravity, weight transfer and forces on springs during braking and cornering, plots of tractive and normal load on tyre during braking.
Title Development of a Graphical User Interface (GUI) Based Tool for Vehicle Dynamics Evaluation Authors Mr. Shubham Kedia, Dr. Divyanshu Joshi, Dr. Muthiah Saravanan Mahindra Research Valley, Mahindra & Mahindra, Chennai Objective Objective metrics for evaluation of major vehicle dynamics performance attributes i.e. ride, handling and steering are required to compare, validate and optimize dynamic behavior of vehicles. Some of these objective metrics are recommended and defined by ISO and SAE, which involve data processing, statistical analysis and complex mathematical operations on acquired data, through simulations or experimental testing. Due to the complexity of operations and volume of data, evaluation is often time consuming and tedious. Process automation using existing tools such as MS Excel, nCode, Siemens LMS, etc. includes several limitations and challenges, which make it cumbersome to implement.
A high impetus from Government on road infrastructure development, is giving a fillip to passenger CV space. This has resulted in making the passenger CV segment lucrative enough, thereby pulling in many operators in the business. The quality of road has immensely improved over a decade, as a result of which the average speed and hence the quantum of distance covered by passenger buses has increased significantly. People are preferring to travel in buses over trains, owing to at par ticket cost, high availability, reduced travel time and also improved level of comfort. Aligned to the market need and the trend, OEM's are offering buses with capable powertrains to cater the need of speed, reduced trip time as well as a lot of attention is also being paid to tune in the comfort level for long hauls. A big chunk of passenger travel is catered by the bus operators especially during major festivals in India.
The present work involves Machine Learning (ML) based Multi-objective Multidisciplinary Design Optimization (MMDO) for lightweighting the automotive structures. The challenge in deployment of MMDO algorithms in solving real-world automotive structural design problems is the enormous time involved in solving full vehicle finite element models that involve large number of design variables and multiple performance constraints pertaining to vehicle dynamics, durability, crash and NVH domains. With the availability of powerful workstations and using the advanced Computer Aided Engineering (CAE) tools, it has become possible to generate huge sets of simulation data pertaining to multiple domains.
Objective: The Objective of the research is to detect drop in level of pressure in the wheel with respect to nominal pressure using data obtained from speed sensors. The research discusses the standard procedure of experimentation to obtain data which eventually used to produce results. This procedure is taken from principles Design of Experiments. Statistical tools are used to analyze and give determining factors for pressure variation. Methodology: To study idea, we made use of two-wheeler platform and collected data of wheel speed sensors on both wheels. The idea is when there is any change in tire pressure the radius of the wheel also changes and usually this relation is direct. Hence, change in tire pressure changes the angular velocity of the wheel. In this approach wheel speed sensors are used to measure the angular speed for standard and reduced pressure conditions.
A new appraisal of the thermomechanical behaviour of a hybrid composite brake disc in a formula vehicle Research Objective This paper presents a hybrid composite brake disc with reduced Un Sprung Weight clearing thermal and structural analysis in a formula vehicle.Main purpose of this study is to analyse thermomechanical behaviour of composite brake disc for a formula vehicle under severe braking conditions. Methodology In the disk brake system, the disc is a major part of a device used for slowing or stopping the rotation of a wheel. Repetitive braking of the vehicle leads to heat generation during each braking condition. Based on the practical understanding the brake disc was remodelled with unique slotting patterns and grooves, using the selected aluminium alloy of (AA8081) with reinforcement particle of Silicon carbide (SiC) and Graphite (Gr) as a hybrid composite material for this proposed work.
Objective To achieve better fuel economy and reduced carbon footprint, OEMs are reducing the sprung and unsprung mass. This translates into a reduction in stiffness which profoundly deteriorates the handling/road holding characteristics of the vehicle. To model these changes in stiffness, modifications are made to suspension roll stiffness at the front and rear. This study compares different configurations of roll stiffness and evaluates vehicle behavior using frequency response characteristics and phase change of Yaw Gain recorded. The present work associates acquired data with subjective feedback to outline the shift in vehicle balance emerging from a variation of sprung and unsprung mass ratio. Methodology To study the frequency response characteristics of the vehicle, the pulse input is chosen for this. An ideal pulse input’s Fourier transform represents constant amplitude over all the frequency ranges. By giving a single input, the system is subjected to a range of frequencies.