Vehicle Design Parameters Research Articles

DYNAMICS AND STABILITY OF EMERGENCY VEHICLES ON DIFFICULT TERRAIN

This research paper examines the nuances of the dynamics and stability of emergency vehicles when maneuvering over complex terrain, offering a multifaceted analysis that combines theoretical modeling and empirical research. Central to the considerations is the study of the interaction between vehicle design and features of various landscapes, including mountain, forest and urban environments. The research uses a synergistic approach that interweaves advanced mathematical modeling techniques such as computational fluid dynamics and finite element analysis with experimental validation in real-world conditions. The methodology clarifies the critical role of vehicle design parameters, such as suspension tuning and aerodynamic properties, in determining vehicle performance in challenging environments. The study highlights the relevance of terrain-dependent speed limits and maneuvering strategies, advocating for modular vehicle designs and terrain-independent technologies. The paper not only makes a significant contribution to the optimization of emergency vehicles, but also paves the way for future research in the areas of artificial intelligence-driven control systems, sustainable propulsion technologies, and predictive performance modeling. Integrated solutions in this area re key to improving the efficiency and safety of rescue operations in diverse and challenging environments.

An integrated data-driven framework for vehicle quality analysis based on maintenance record mining and Bayesian network

PurposeThe purpose of this paper is to present an integrated data-driven framework for processing and analyzing large-scale vehicle maintenance records to get more comprehensive understanding on vehicle quality.Design/methodology/approachWe propose a framework for vehicle quality analysis based on maintenance record mining and Bayesian Network. It includes the development of a comprehensive dictionary for efficient classification of maintenance items, and the establishment of a Bayesian Network model for vehicle quality evaluation. The vehicle design parameters, price and performance of functional systems are modeled as node variables in the Bayesian Network. Bayesian Network reasoning is then used to analyze the influence of these nodes on vehicle quality and their respective importance.FindingsA case study using the maintenance records of 74 sport utility vehicle (SUV) models is presented to demonstrate the validity of the proposed framework. Our results reveal that factors such as vehicle size, chassis issues and engine displacement, can affect the chance of vehicle failures and accidents. The influence of factors such as price and performance of engine and chassis show explicit regional differences.Originality/valuePrevious research usually focuses on limited maintenance records from a single vehicle producer, while our proposed framework enables efficient and systematic processing of larger-scale maintenance records for vehicle quality analysis, which can support auto companies, consumers and regulators to make better decisions in purchase choice-making, vehicle design and market regulation.

Adaptive MATLAB GUI for Hydraulic Brake Stopping Distance Simulation

The crucial segment of any vehicle is the braking unit which decides the vehicle’s performance and passenger safety on a large quotient. It is highly essential to decelerate the vehicle within a reduced distance to avoid any collision. The stopping distance is also dependent on many characteristics apart from the vehicle itself which are GVW(Gross Vehicle Weight), brake sizing, Road Friction, and other vehicle design parameters. Hereby, the result of any brake system is the Stopping Distance. Therefore, for every vehicle, it is inevitable to design in such a way that meets all requirements to pass the safety standards. In this article, we provide an interactive GUI of Mathematical modelling using MATLAB that depicts the running vehicle simulation while the brakes are applied and highlights the Stopping distance for any given inputs. Here, we have used a novel approach to calculate the stopping distance, given we have all vehicle properties. Importantly, cuts the design phase to a large extent saving an ample amount of time with all ease of access and dexterity. The core features of GUI: One will be able to generate and compare stopping distance and other brake-related results for any two given different design scenarios. GUI is automated so that it can simulate the stopping distance just by providing the brake/vehicle parameters inputs to the interface. Additional functionalities to compare design results for various standards (FMVSS, IS, ECE) can also be done effectively. Keywords: Braking Systems, MATLAB Application, Vehicle Safety, Stopping Distance

Machine learning-based surrogates for eVTOL performance prediction and design optimization

<p>Predicting the performance of different electric vertical take-off and landing (eVTOL) vehicle designs is paramount to vehicle manufacturers and hobbyists. These vehicles' maximum flight time (endurance) and maximum flight distance (range) depend on design and operational parameters relating to their structure, propulsion system, payload, and mission profile. In recent years, sophisticated physics-based models have been developed to estimate and optimize their aerodynamic, propulsion, and electrical performance. Integrating and simulating those models can closely estimate a vehicle's endurance and range. However, this demands advanced knowledge of different subsystems utilized and extensive computational resources limiting the wide-scale utilization of such models. This paper showcases the development and implementation of a framework to train simpler machine learning-based surrogates. The surrogate models are trained on a limited number of eVTOL performance estimates generated by physics-based models and can mimic them accurately. Forty-seven thousand eVTOL vehicle designs were simulated to generate the training data for various machine-learning models. These include several decision tree models, K-nearest neighbor models, linear regression models, and a multi-perceptron neural network model. Vehicle design and operational parameters such as propeller size, payload mass, drag coefficient, velocity, and motor and battery parameters are used as features, and vehicle endurance and range estimates are used as targets. Compared to the alternative approaches, these surrogate models are computationally very efficient and easy to understand and use. Testing on hold-out datasets shows excellent performance, with multiple models having a mean average percentage error of less than 2% in estimating vehicle endurance and range.</p>

Research, development and production costs prediction parametric model for future civil hypersonic aircraft

Assessing the economic viability of new high-speed systems concepts since the early design phases is crucial for the success of future hypersonic vehicles including cruisers, reusable access-to-space and re-entry systems. Besides literature reports few parametric cost models for high-speed vehicles, all of them makes exclusively use of mass as parameter and none of the models moves beyond the vehicle level. This paper describes a new parametric cost estimation model which moves beyond the state-of-the-art methodologies (1) by integrating vehicle design and operational parameters (in addition to the mass) as cost drivers for the prediction of the vehicle life-cycle cost, (2) by introducing prediction margins accounting for the uncertainties on the data-driven correlations, (3) by providing a first estimate of the costs of every on-board subsystem, including combined cycle engines and multi-functional subsystems, (4) by increasing the granularity of the analysis up to technology level, thus providing a valuable support to Technology Roadmaping activities. The parametric cost estimation model has been refined and exploited in the context of the Horizon 2020 STRATOFLY project, where the technological, operational, environmental, and economic viability of a Mach 8 waverider concept have been investigated.

Баллистическое проектирование ракеты-носителя со спасаемым головным обтекателем

The paper focuses on the problem of the ballistic design of a two-stage launch vehicle for the case when the payload fairing is returned by using its flaps as the lifting surfaces of the first-stage reusable boosters. The fairing flaps must be opened after the velocity pressure reaches its maximum value. Therefore, the trajectory in the operation section of the first-stage boosters is assumed to be vertical. The flight along the curved part of the trajectory is carried out by the second-stage booster. In this study, we introduced an algorithm for selecting design parameters, developed an original program in the Wolfram Mathematica computer algebra system, and found the rational design parameters of the launch vehicle.

Development of the Reduced-Scale Vehicle Model for the Dynamic Characteristic Analysis of the Hyperloop

This study addresses the Hyperloop characterized by a capsule-type vehicle, superconducting electrodynamic suspension (SC-EDS) levitation, and driving in a near-vacuum tube. Because the Hyperloop is different from conventional transportation, various considerations are required in the vehicle-design stage. Particularly, pre-investigation of the vehicle dynamic characteristics is essential because of the close relationship among the vehicle design parameters, such as size, weight, and suspensions. Accordingly, a 1/10 scale Hyperloop vehicle system model, enabling the analysis of dynamic motions in the vertical and lateral directions, was developed. The reduced-scale model is composed of bogies operated by Stewart platforms, secondary suspension units, and a car body. To realize the bogie motion, an operation algorithm reflecting the external disturbance, SC-EDS levitation, and interaction between the bogie and car body, was applied to the Stewart platform. Flexible rubber springs were used in the secondary suspension unit to enable dynamic characteristic analysis of the vertical and lateral motion. Results of the verification tests were compared with simulation results to examine the fitness of the developed model. The results showed that the developed reduced-scale model could successfully represent the complete dynamic characteristics, owing to the enhanced precision of the Stewart platform and the secondary suspension allowing biaxial motions.

Methods and simulation to reduce fuel consumption in driving cycles for category N1 motor vehicles

The paper presents the results of using the simulation model estimating the fuel consumption of a light commercial vehicle in road traffic cycles; virtual tests are performed. The impact analysis of the motor vehicle design parameters on fuel consumption in NEDC and WLTC cycles is conducted. Numerical values of average fuel consumption are obtained for variation of the main parameters of the structure in NEDC and WLTC cycles. Energy distribution is shown during the motion of category N1 light commercial vehicle.

Performance Assessment of Discrete-Event Drag Modulation for Mars Entry with Real-Time Guidance

Entry flight performance is assessed for single-stage discrete-event drag-modulation trajectory control on Mars with two different real-time guidance algorithms: a heuristic velocity trigger and numerical predictor–corrector. Three degree-of-freedom simulation and Monte Carlo techniques are used to determine flight performance across a range of mission and vehicle design parameters. Trends are identified in flight performance across different initial conditions, ballistic-coefficient ratios, and target ranges. Results indicate that both guidance algorithms can provide landing accuracy better than 10 km across likely vehicle properties and entry conditions. The heuristic velocity trigger performs nearly as well as the numerical predictor–corrector for low-ballistic-coefficient ratios and entry flight-path angles steeper than approximately . The numerical predictor–corrector provides consistent flight performance across all feasible mission and vehicle parameters with accuracy better than approximately 5 km. Overall, single-stage discrete-event drag-modulation trajectory control is a feasible option for accurate landings for ballistic coefficients below approximately and landed altitudes above 0 km.

Effect of Reynold’s number on effective heat transfer dissipation of braking system

Reynold’s number is an effective parameter in the thermal and computational fluid dynamics analysis of a braking system. Laminar, forced and normal convection is there for a braking system due to variation in Reynold’s number. Due to a change in Reynold’s number, the Heat convection parameter is affected for a disc brake, and temperature variation is observed. Stainless Steel 410 material is used for brake disc and due to variation of heat convection , situations Laminar and forced convection has been considered and temperature variation in all the situations has been concluded through Thermal & CFD heat transfer analysis using ANSYS. Fine Meshing has been carried out during the thermal and CFD heat transfer analysis for better efficiency in results. Mathematical calculations have been carried out using MATLAB. Vehicle design parameters have been taken into the consideration to generate efficient heat flux and heat convection for the disc brake to achieve an efficient braking system for the vehicle.

부가유로를 갖는 MR 댐퍼의 퍼지 제어성능 및 승차감 평가

Recently, with the increasing demand to improve the ride comfort of passengers, studies on the Magnetorheological(MR) dampers that improve the ride comfort have been increased significantly. Among these studies, study on the MR damper with additional flow path is being focused due to its good ride comfort and driving performance. However, there are no studies related to sensitivity analysis and fuzzy control. Particularly, to determine the design parameters of passenger vehicle, sensitivity analysis is required. Therefore, in this study, to evaluate the driving performance according to various driving conditions, fuzzy rule and design direction are discussed. After constructing the dynamic control system using MATLAB and Simulink, the effectiveness of the proposed sensitivity analysis and fuzzy control is verified.

Sensitivity of Design Parameters on State of Charge of Electric Vehicles

Paper This study is to find out how sensitively the design parameters of Electric Vehicle (EV) will affect the State Of Charge (SOC) it. The main design parameters that selected are the frontal area of the vehicle, vehicle mass and coefficient of drag. With the help of Advisor software MatLab model of EV s made. The vehicle model is run in different universally accepted driving cycles with different values of design parameters selected. The analysis is done using the sensitivity analysis method, which will show how one parameter is affecting others.

INVESTIGATE VEHICLE DESIGN PARAMETERS EFFECT ON DYNAMIC VEHICLE STABILITY

In this paper, a two degree of freedom linear vehicle model is proposed to investigate dynamic vehicle stability under varies vehicle maneuvers. The simulation is developed using MATLAB/Simulink application program to predict the vehicle dynamic stability under different maneuvers. To investigate vehicle stability, the Steering wheel angle is chosen to be the primary model input for the analysis procedures. The developed model is validated via Step steer input. Moreover, a new typical steer wheel angle is developed to examine highway predicted vehicle output within its maneuver. The vehicle dynamic outputs, namely, yaw rate and lateral acceleration are adopted for all the investigated maneuvers. It is found that the vehicle design parameters such as changing the vehicle center of gravity (CG) position, vehicle mass, tire cornering stiffness and vehicle speed have a significant influence on the vehicle dynamic stability. Change in vehicle center of gravity position is the most parameter has an influence in vehicle stability dynamics. 10% forward and reward in the C.G position change in under steering gradient, it changes steering in vehicle model from under steering type to over steering type, on the other hand, vehicle mass change ±10% change in vehicle mass has the latest influence in vehicle stability dynamic. Others have a different rate effect on vehicle dynamic stability.

Parametric Optimization and Experimental Validation for Nonlinear Characteristics of Passenger Car Suspension System

The study deals with the design of the automotive suspension system to better dynamic characteristics in an uncertain operating atmosphere. Vehicle design parameters are to be optimized to achieve better passengers comfort, vehicle body stability, and road holding as the measure of suspension system performance improvement. The design of experiments gives the optimum parametric combination in the domain on the basis of vertical body acceleration data obtained by simulation of a 2-DOF nonlinear quarter car model. Moreover, the nonlinear hysteric behavior foremost design parameters have been characterized through the theoretical and experimental analysis in order to validate the design and to check the analogical viability of the derived model. Finally, the proposed methodology ascertains the optimum design of the suspension system in the time and cost-effective manner. The developed passive design of car suspension system exhibits excellent vibrational characteristics and convinces the acceptable range of vehicle vibration as suggested by ISO-2631-1997.

Features of the choice of the trajectory and stages of the flight of an unmanned aircraft on solar energy in a restless atmosphere

When forming the design parameters of an unmanned aerial vehicle (UAV) on solar energy, it is important to consider the peculiarities of energy supply not only when performing horizontal flight, but also at other stages (take-off, landing, maneuver, etc.), which ultimately form a common flight trajectory the implementation of which ensures the implementation of the specific task assigned to the UAV. However, the flight should be considered taking into account the actual operating conditions, including atmospheric factors. Determining the features of planning the trajectories and stages of flight of a UAV on solar energy during the implementation of a long flight, considering energy, design constraints and actual operating conditions, is the goal of this work. The possible trajectories of flight of UAVs on solar cells are determined in accordance with the typical tasks of its practical application. A discrete model is proposed for planning a trajectory of a route for a UAV on solar cells. The principles of the implementation of the stages of takeoff and landing of UAVs on solar energy are described, the dependencies between the energy consumption and the main parameters of each stage are determined. The dependences are obtained for determining the main components of the energy balance of UAVs on solar energy on the parameters of curvilinear flight. Verification of the obtained dependences was carried out by comparing the calculated and experimental (flight) data for a particular UAV on solar energy, which is of the mini class by mass. The convergence of the results of calculation and experiment is in the range of 15–20 %. The factors acting on an aircraft in a restless atmosphere, their effect on operational and design constraints are established. A generalized analytical model was obtained to determine the conditions for the implementation of a long flight (4–6 hours) of a solar-powered UAV, considering: mass, aerodynamic, energy characteristics; trajectory, atmospheric and operational conditions. The results of the study can be used at forming the shape of a UAV on solar energy at the stage of its preliminary design.

Periodically Cruising Hypersonic Vehicle With Active Cooling: An Optimal-Control Based Design Approach

Periodic cruise has been proven an effective trajectory to conserve fuel and alleviate aerodynamic heating for hypersonic cruise vehicles (HCVs). This work studies how to adopt an HCV with active cooling to periodic cruise. In this adaption, payload capacity is to maximize, whereas the cooling requirement is to reduce. The differences in requirements for subsystems between periodic and steady cruises have been made clear. The results indicate that periodic cruise principally transfers the burden of thermal protection to the structure, and that periodic cruise is more effective to trade payload capacity for larger reduction of cooling requirement. Afterward, impacts of design parameters of the vehicle on payload capacity and cooling requirement have been discussed. The results indicate that insulation thinner than 3 mm, a planform loading lower than 220 kg/m2, or a large engine is not suggested for the vehicle studied herein. This work figures out the correlation between design parameters of vehicle and features of periodic cruise trajectory. It could help to improve the feasibility of periodic cruise for a hypersonic vehicle, which is significant for realization of the long-range hypersonic cruise.

Entry Trajectory Options for High Ballistic Coefficient Vehicles at Mars

Future large-scale Mars surface exploration missions require landed masses beyond the capability of current entry, descent, and landing technology. Hypersonic trajectory options for large ballistic coefficient vehicles are explored to assess the potential for improved landed mass capability in the absence of landed accuracy requirements. Hypersonic trajectories appropriate for use with supersonic parachute and supersonic retropropulsion descent systems are studied. Optimal control techniques are used to determine hypersonic bank-angle control profiles that achieve favorable conditions at terminal descent initiation. Terminal descent initiation altitude-maximizing bank strategies for parachute descent systems are explored across vehicle and mission design parameters of interest. A tradeoff between altitude and flight-path angle at terminal descent initiation is identified. Hypersonic trajectories that minimize required propellant for propulsive descent are identified and studied parametrically. A hypersonic ballistic coefficient and lift-to-drag ratio are shown to have the largest effects on required propellant mass fraction; changes to the vehicle state at entry interface have a smaller effect. The space of reachable supersonic retropropulsion ignition states is presented over a range of vehicle and trajectory parameters. Overall, results indicate execution of an appropriate hypersonic bank profile can significantly increase the parachute deploy altitude for parachute descent systems or reduce the amount of propellant required when compared to full lift-up entry for supersonic retropropulsion descent systems operating at Mars.

Comparison of simulation models NRMM and NTVPM for assessing military tracked vehicle cross-country performance

Mobility of ground vehicles is an important issue for defence operations. In the United States and some other NATO countries, the NATO Reference Mobility Model (NRMM) is currently used to evaluate military ground vehicle mobility. The cross-country performance prediction module of NRMM is based on empirical relations established with test data primarily collected decades ago. It has inherent limitations, such as the uncertainty whether the empirical relations can be extrapolated beyond the test conditions upon which they were derived. This paper describes a comparison of the empirically-based NRMM with the physics-based Nepean Tracked Vehicle Performance Model (NTVPM) for assessing the cross-country performance of military tracked vehicles. It examines the soundness of the methodologies of NRMM and NTVPM, the adequacy of the vehicle design parameters and terrain characteristics that they take into account, the user friendliness of their operations, and the correlations between the measured cross-country performance of a notional tracked vehicle (an armoured personnel carrier) and that predicted by the two simulation models on sandy terrain, muskeg and snow-covered terrain. Based on the results of the evaluation, it appears that the physics-based NTVPM has potential as the basis for the development of the next generation simulation model for assessing the cross-country performance of military tracked vehicles.

ELDERLY DRIVER INGRESS AND EGRESS FROM A VEHICLE: PERCEIVED DISCOMFORT AND TASK DURATION

The time it takes a driver to get in and out of a vehicle, and how comfortably they can perform this task, are important considerations for vehicle design. Older drivers are keeping their licenses longer and driving more miles, making it more important than ever to study how vehicle design parameters interact with the sensorimotor changes due to aging and disease. 48 older subjects (27 males, 21 females) between the ages of 67 and 89 years were tested. Twenty-four were healthy, 12 had osteoarthritis and 12 had diabetic polyneuropathy. Subjects completed both physical capacity tests and motion capture testing of ingress/egress in seven different vehicles represented by the Human Occupant Package Simulator. A control group of 48 younger drivers also completed ingress/egress testing. Motions, captured using Vicon cameras, were used to calculate the main outcome variables of Ingress Time and Egress Time. The third main outcome, Perceived Discomfort, was measured by asking the subjects to rate each ingress/egress motion. Inverse Egress Time and Discomfort were significantly correlated, with a correlation coefficient of -0.45. Longer times were associated with greater discomfort. Linear mixed-effect modeling showed that vehicle design factors that significantly influenced the discomfort or the duration of ingress/egress were the height of the vehicle seat with respect to the ground, as well as the location of the seat with respect to the sill and the roof rail. In conclusion, Perceived Discomfort and Ingress/Egress Time provide guidance on how vehicle design can improve the driving experience for elderly drivers.

Simulation Technique of Kinematic Processes in the Vehicle Steering Linkage

The results of the investigation of the turning kinematics of the steerable wheels of the KrAZ-7634NE off-road vehicle with a wheel formula 8x8 and two front steer axles are given. The theoretical relations between the steer angles of the steerable wheels on the basis of the scheme of double-axle steering turning of the vehicle are shown. The mathematical model of flat four-bar vehicle steering linkage is developed, it determines the relation between the steering linkage left and right steering arms turning angles at any turning radius of the vehicle. KrAZ-7634HE steering three-dimensional model was created and simulation technique of its work was carried out using Creo software. It has been shown that the flat steering linkage model provides sufficient accuracy of calculations in analysis of turning kinematics. The design data can be used for any vehicles that have a similar steering linkage, they allow to analyze the impact of the vehicle design parameters on the turning kinematics and optimize them. Further study of the impact of the kingpin inclinations on the steering linkage kinematic and power characteristics are required.