Papers by Keyword: Vehicle Dynamics

Abstract: The transition of the automotive sector towards autonomous mobility requires a sophisticated amalgamation of cutting-edge hardware, redundant software frameworks, and accurate mathematical modeling. This research examines the technologies that facilitate autonomy in passenger vehicles, highlighting the shift from distributed to centralized zonal systems. The core focus of this study is the development of a unified modeling framework that integrates Kinematic and Dynamic Bicycle Models. Kinematic models prove sufficient for operations at low speeds, while dynamic models are essential for maintaining stability at high speeds, where tire slip and lateral forces gain prominence. This research provides a comprehensive classification of existing designs and introduces a mathematical framework that facilitates transitions between modeling paradigms based on the vehicle's state. A detailed numerical calculus experiment is performed, simulating the transition from a low-speed urban turn to a high-speed interstate lane change. This illustrates the necessity for an integrated modeling approach to ensure safe autonomous navigation.

Abstract: Most advanced driver assistance systems (ADAS) are intended to improve ride comfort for vehicle suspension systems. A new road estimation method is proposed as a means of observing the road profile level. To achieve this, two complexity levels (quarter car and half car models) are presented and developed in Matlab to analyze the vertical vibration of a vehicle. The unknown input observers are then designed for observing unknown states and road profile level. The necessary measurements are the accelerations of the centers of the wheels. The results of simulations conducted with random road excitation show successfully simulated experimentations of the method using a realistic simulator as well as its robustness.

Abstract: The Triple Hybrid Hydrogen Bus project comprises research and development, implementation and a test operation of a city bus with hybrid electric propulsion using hydrogen fuel cells. The mass distribution and the total bus mass are rather different from common buses. This is, among others, the reason for investigating the bus driving stability. In order to obtain a tool for dynamic analysis, multibody models of the bus were created. Verification of multibody models was performed based on the comparison of simulation results and experimental measurements focused on handling behaviour of the bus. To perform the simulations two approaches were used. The first (original) one, at which the initial position of the bus multibody model at the beginning of the simulation of the manoeuvre depends on the bus motion trajectory, and the second (new) one, at which the initial position of the bus multibody model at the beginning of the simulation of the manoeuvre is set an equilibrium position.

Abstract: Development of a reliable high-performance multirotor unmanned aerial vehicle (UAV) requires an accurate and practical model of the vehicle dynamics. This paper describes the process and results of the dynamic modeling of an unmanned aerial platform known as quadrotor. To model a vehicle dynamics, elementary physical and aerodynamical principles has been employed. Parameter estimations, from a UAV design have been obtained through direct and indirect measurements. In addition to standard configuration of VTOL (Vertical Take-Off and Landing) platform, the amortized landing gear, modeled as spring-damper system, has been added. The resulting model has been implemented in a simulation environment under MATLABs toolbox, SIMULINK. Some numerical results are presented to illustrate response of the open loop system to specific commands.

Abstract: In order to adapt to new modern car styling, the aerodynamic numerical simulations based on computational fluid dynamics (CFD) are applied to the process of car styling. We received the early modeling design automobile aerodynamic coefficients, pressure distribution, velocity contours and other body outflow field data after the CFD post, combined with these data some advice to improve the aerodynamic drag of the designed car are given. Proposed aerodynamic automobile design method is based on numerical simulations, according to experience in air vehicle dynamics studies.

Abstract: The paper describes an analysis of suitability of a tire model and its model properties with respect to values of the car body acceleration, or running stability of the vehicle. In the frame of the solution simulations were run on a modified example model of a vehicle from the library of ADAMS/Car. The monitored dynamic parameters were a function of the used tires and chosen driving maneuvers. Evaluation of the simulations was done independently for inflated tires and for underinflated tires. The overview of the evaluated results of the simulations is presented in a table, while the weight parameter reflects the accuracy of calculated values.

Abstract: The previously fabricated all terrain vehicle (ATV) chassis and components' designs are further analyzed. The analysis consider the weight distribution ratio during acceleration and braking for the ATV components namely wishbone arm, swing arm and shaft. Preliminary analysis of torsion and static are also performed on the chassis and components. The analysis is performed using commercial computer aided design (CAD) software. The results show good data in term of factor of safety. With further development and research, the ATVs are subjected for improvement. The sustainability of the design and development of the ATVs depends on the material selection, design criteria and components availability.

Abstract: This paper presents a 9-degree of freedom (9-DOF) vehicle model combined with a closed-loop driver model for the purpose of developing vehicle lateral control. The driver model was developed to control the steering angle and uses a lookup table path as a reference for the control input. The proposed driver model for the outer-loop controllers are combination of proportional-integral (PI) control with a yaw effect adaptive fuzzy logic control. The outer-loop controllers were evaluated by simulation using predefined path for lane keeping manoeuvre at 80 km/h constant speeds. The simulation results show that the proposed driver model is capable of improving Y-axis trajectory error and Y-axis trajectory manoeuvres significantly.

Abstract: Two units of all terrain vehicles (ATV) have been designed and developed by 3^rd year automotive students of Faculty of Mechanical Engineering (FME), Universiti Teknikal Malaysia Melaka (UTeM). The purposes of this project are to design and develop low cost ATVs. The students have to organize themselves to design and build the ATVs within budget constraint. This project emphasizes on the practical and engineering applications of the subjects Vehicle Dynamics and Automotive Technology which are taken by the students within the same semester (Semester II, Session 2012/2013). The students have all the freedom in deciding the specifications of the ATVs. A 110 cc 4 strokes motorcycle engine is used for the powertrain. Design and analysis of the components are performed using commercial computer aided design (CAD) software. Basic fabrication processes such as cutting, fitting and welding are carried out by the students. The ATVs are evaluated based on functionality and design. The low cost conceptual ATVs have been successfully designed, developed and tested. With further development and research, the ATVs are subjected for improvement. The sustainability of the design and development of the ATVs depends on the material selection, design criteria and components availability.

Abstract: Tougher request that are being formulated again and again regarding a vehicle’s dynamic performances and its fuel efficiency require a deeper study over the influence of various parameters over to the vehicle dynamic behavior. In the specialty literature we find appreciations both quantitative and qualitative regarding the influence of certain functional parameters, and how their adjustments have an impact on to the vehicle’s performances. We have to mention that the literature guides its self when analyzing the influence of certain parameters after a very restrictive methodology: when studying how a parameter influences a certain behavior all the other parameters are considered to be constant, which obviously does not happen in reality.