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2015-04-21
Standard
ARP4834B
This SAE Aerospace Recommended Practice (ARP) sets forth criteria for the selection, inspection, retread and repair of worn civil aircraft tires, and the means to verify that the retreaded tire is suitable for continued service. This document is applicable to both bias ply and radial aircraft tires qualified subsequent to the adoption of this document.
2015-04-14
Collection
Topics of this technical paper collection include (but are not limited to) nonlinear behavior of tires and wheels, static/dynamic stress analysis, nonlinear material modeling, contact stress, impact, noise, vibration, traction, hydroplaning, effect of tires on vehicle performance, rolling resistance, and durability.
2015-04-14
Collection
This technical paper collection is focused on vehicle dynamics and controls using modeling and simulation, and experimental analysis of passenger cars, heavy trucks, and wheeled military vehicles. The papers address active and passive safety systems to mitigate rollover, yaw instability and braking issues; driving simulators and hardware-in-the-loop systems; suspension kinematics and compliance, steering dynamics, advanced active suspension technologies; and tire force and moment mechanics.
2015-04-14
Collection
This technical paper collection provides information on steering and suspension related topics as it applies to ground vehicles. Papers address new approaches as well as advances in application of steering, suspension related technologies.
2015-04-14
Technical Paper
2015-01-1522
Takahiro Yokoyama, Koji Hiratsuka, Shinya Notomi
Abstract Vehicle dynamic performance on snow-covered roads is one aspect of performance that is influenced by tire performance. Much research concerning a vehicle's performance on snow-covered roads has focused on being directed to vehicle control technology that increases control when the tire-slip ratio is larger, such as anti-lock braking systems (ABS) and electronic stability control (ESC). There has been little research, regarding performance when the slip ratio on a snow- covered road is smaller. We studied the friction performance of tires on snow-covered roads to predict vehicle performance within the grip range. We propose a technology for predicting vehicle performance within the small slipangle range and also verify its effectiveness. We established the tire characteristics that assure the grip range on a snow-covered road using performance indicators.
2015-04-14
Technical Paper
2015-01-1515
Kwangwon Kim, Hyeonu Heo, Md Salah Uddin, Jaehyung Ju, Doo-Man Kim
Abstract Due to the relatively high freedom of selection of materials associated with a simple manufacturing method, a nonpneumatic tire (NPT) can be manufactured with a low viscoelastic energy loss material. A highly increasing demand to reduce greenhouse gases drives engineers to explore NPTs. NPTs consisting of flexible spokes and the shear band are still at an early stage of research and development. An optimization study of NPTs' geometry needs to be conducted, which is the objective of this paper. Parametric studies and design of experiments (DOE) of an NPT are conducted with a hyper-viscoelastic finite element (FE) model to determine the effects of three design variables on rolling resistance: the thickness of cellular spokes, the cell angle, and the shear band thickness. Considering vehicle load carrying capacity and riding comfort, ranges of vertical deflection between 18 and 20mm and contact pressure between 0.6 and 0.8MPa are selected as constraints for the optimization.
2015-04-14
Technical Paper
2015-01-1516
Mohammed K Billal, Rizwan Basha, Anilkumar Nesarikar, Abdul Haiyum, Thomas Oery
Abstract Damages (fracture) in metals are caused by material degradation due to crack initiation and growth due to fatigue or dynamic loadings. The accurate and realistic modeling of an inelastic behavior of metals is essential for the solution of various problems occurring in engineering fields. Currently, various theories and failure models are available to predict the damage initiation and the growth in metals. In this paper, the failure of aluminum alloy is studied using progressive damage and failure material model using Abaqus explicit solver. This material model has the capability to predict the damage initiation due to the ductile and shear failure. After damage initiation, the material stiffness is degraded progressively according to the specified damage evolution response. The progressive damage models allow a smooth degradation of the material stiffness, in both quasi-static and dynamic situations.
2015-04-14
Technical Paper
2015-01-1096
Robert Lloyd
Abstract The frequent stops of the typical postal delivery vehicle make it an attractive application for regenerative braking. The hydro-mechanical automatic transmission described in SAE paper 2014-01-1717 contains all the functions necessary to implement hydraulic regenerative braking including the accumulator and reservoir. This paper describes the substitution of the hydro-mechanical transmission for the present transmission of the postal LLV vehicles and estimates the performance benefits. The result represents a low impact path for the US Postal Service to extend the useful life of the LLV vehicles and increase the mpg by approx. 100%. A cost comparison between a convention ICE mid-sized passenger sedan and a similar size gas/hydraulic hybrid vehicle illustrates the cost advantage of the hydraulic approach using the new transmission design. Besides lower cost, the vehicle will have greater initial acceleration and 25%+ better mpg.
2015-04-14
Technical Paper
2015-01-0689
R. Rajendran, G. Ramanjaneyulu, T R Tamilarasan, Vladimir I. Semenov
Abstract Cryogenic treatment has a good potential to significantly increase the service life of automotive components, where friction and wear are the major factors in their operation leading to failure. Cryogenic treatment changes the surface as well as the core properties of the component in comparison with other treatments. It has significant improvement in wear and toughness. Numerous studies have been conducted on cryogenic treatment of steels and tool steels showing significant improvements in wear resistance, only minimal work has been done in cast irons. In this study, the effect of cryogenic treatment on the wear resistance, hardness, tensile strength, toughness and microstructure of spheroidal graphite iron was assessed. The deep cryogenic treatment was carried out at 87K for 12h and annealed in the chamber itself. The samples were tempered at 473K for 1 h.
2015-04-14
Technical Paper
2015-01-0576
Jiaquan Chen, Yongfeng Jiang, Min Qin, Wenquan Hao, Yin-Ping Chang, Lingge Jin
This research proposes an automatic computer-aided design, analysis, and optimization process of a twist beam rear suspension system. The process combines CAD (Computer-Aided Design), CAE (Computer-Aided Engineering), and optimization technologies into an automation procedure, which includes: structural design, dynamic analysis, vibration analysis, durability analysis, and multidisciplinary optimization. The automation results shown the twist beam rear suspension weight reduced, the durability fatigue life increased, and the K&C (kinematics & compliance) characteristics are improved significantly.
2015-04-14
Technical Paper
2015-01-0617
Jie Zhang, Xiao Chen, Bangji Zhang, Lifu Wang, Shengzhao Chen, Nong Zhang
Abstract This paper demonstrates time response analysis of the mining vehicle with bounce and pitch plane hydraulically interconnected suspension (HIS) system. Since the mining vehicles working in harsh conditions inducing obvious pitch motion and the hard stiffness of suspensions leading to the acute vibration, the passive hydraulically interconnected system is proposed to provide better ride comfort. Furthermore, the hydraulic system also increases the suspension stiffness in the pitch mode to prevent vehicle from large pitch motions. According to the hydraulic and mechanical coupled characteristic of the mining vehicles, a 7degrees of freedom (7-DOFS) mathematical model is employed and the state space method is used to establish the mechanical and hydraulic coupled dynamic equations. In this paper, the vehicles are subjected to straight line braking input, triangle block bump input applied to the wheels and random road tests.
2015-04-14
Technical Paper
2015-01-0616
Aref M.A. Soliman
Abstract In this paper, passive and various types of intelligent vehicle suspension systems are compared in terms of their relative ride performance capabilities and power requirements. These systems are active, two and three setting switchable dampers suspension systems. The control gains of the intelligent systems are obtained using optimal control theory and gain scheduling strategy (GS) is used for the system behaviour. In the first strategy (GS) used, gains are selected based on suspension working space. While, the other strategy (GS), gains are selected based on body acceleration. These strategies are used to maintain suspension working space and dynamic tyre deflection levels within design limits and to minimise body acceleration level. The mean power consumed in rolling resistance and the mean power dissipation within the suspensions is evaluated.
2015-04-14
Technical Paper
2015-01-0613
Donghong Ning, James Coyte, Hai Huang, Haiping Du, Weihua Li
Abstract This paper presents a study on experimental vibration simulation using a multiple-DOF motion platform for heavy duty vehicle seat suspension test. The platform is designed to have 6-DOF with the advantages of high force-to-weight ratio, high dexterity and high position accuracy. It can simulate vehicle vibrations in the x, y and z translational axis and in the roll pitch and yaw axis rotation. To use this platform to emulate the real vibration measured from vehicle seat base under real operation for vehicle seat suspension test in lab, an Inertial Measurement Unit (IMU) is applied to collect the acceleration data from a real vehicle. An estimation algorithm is developed to estimate the displacement from the measured acceleration. The estimated displacement is then used to calculate the length of each leg of the platform so that the platform can generate the motion similar to the measured one.
2015-04-14
Technical Paper
2015-01-0614
Ye Zhao, Liangmo Wang, Xiangli Yang, Liukai Yuan, Zunzhi Zhang
Abstract In most cases, researches on the ride performance of air suspension system are based on simplified mathematical models which could be too theoretical or not be able to consider the coupling relationship between the various components so that they behave far away from the actual vehicle system. This paper represents the study on the ride performance of an air suspension vehicle based on the accurate complex whole vehicle model which was established though ADAMS and Matlab. The applying of flexible components helped to improve the model accuracy. The stretching and compression test results of the air spring were used to establish the interconnected four-gasbag air suspension system. The vehicle ride performance was studied through the co-simulation between ADAMS and Matlab. The accuracy of the results were verified by the vehicle test results, which demonstrated the reliability of the whole model.
2015-04-14
Technical Paper
2015-01-0608
Gang Tang, Hengjia Zhu, Yunqing Zhang, Ying Sun
Abstract The vehicle ride comfort behavior is closely associated with the vibration isolation system such as the primary suspension system, the engine mounting system, the cab suspension system and the seat suspension system. Air spring is widely used in the cab suspension system for its low vibration transmissibility, variable spring rate and inexpensive automatic leveling. The mathematical model of the air spring is presented. The amplitude and frequency dependency of the air spring's stiffness characteristic is highlighted. The air spring dynamic model is validated by comparing the results of the experiment and the simulation. The co-simulation method of ADAMS and AMESim is applied to integrate the air spring mathematical model into the cab multi-body dynamic model. The simulation and ride comfort test results under random excitation are compared.
2015-04-14
Technical Paper
2015-01-0607
Xincheng Liang, Jingshan Zhao
Abstract This paper proposes a theoretical model to interpret the heat generation mechanism and thermal failure of shock absorber. For a common structure of double-tube shock absorber, all frictions between two contacting components of shock absorber are calculated particularly. The heat generation mechanism and heat distribution can be explained with the theoretical model. Thermal failure is a recurrent malfunction for traditional shock absorbers, which leads to shorten the service lives of vehicle components. Heat generation experiments are accomplished to validate the thermal degeneration of shock absorber. So this study is meaningful to develop a new system of vibration attenuation with satisfying reliability, which is essential to improve the riding comfort and handling stability of vehicles.
2015-04-14
Technical Paper
2015-01-0652
Hui Hua, Lifu Wang, Hengmin Qi, Jie Zhang, Nong Zhang
Abstract Air spring due to its superior ride comfort performance has been widely used in distance passenger transporting vehicles. Since the requirements for ride comfort and handling performance are contradict to each other, handling performance and even roll stability are sacrificed to some extent to obtain good ride comfort. Due to the complex terrain and limited manufacturing level, in the past several years, bus rollover accidents with serious casualties have been reported frequently and bus safety has attracted more and more attention from bus manufacturers in China. On one hand the bus standards have to be raised, and on the other hand, novel solutions which can effectively improve the roll stability of air spring bus are needed to replace the inadequacy of anti-roll bars.
2015-04-14
Technical Paper
2015-01-0646
Jian Ou, Qing-lin Zhang, Yong Zhang, E-chuan Yang, Mei-zhi Liu
Abstract The transient response characteristics of a vehicle under steering angle input are important evaluating indicators of vehicle handling stability. For a new developed vehicle, which was found that the transient response under steering angle input is too slow at high speed, a rigid-flexible coupling vehicle model is established in ADAMS/Car based on multi-body dynamics theory. Improvement measures are studied and put forward to improve the transient response characteristics of the vehicle. The sensitivities of transient response to various parameters are analyzed. The optimization method of adjusting the tire cornering stiffness and moving forward the mass center is adopted. The test data after improvement show that the response time of yaw velocity is shortened obviously. Meanwhile, the value of evaluation index in other tests remains basically unchanged.
2015-04-14
Technical Paper
2015-01-0641
R. Pradeepak, Mihir Bhambri, Shafeeq Rahman
Abstract This paper describes about handling validation of a motorcycle on a steady state condition. Nowadays, it is very usual and common to get a feedback by motorcycle test riders that the steering feel is heavy due to which more effort is required to complete a full track circuit. So it has become a necessity to focus the study on handling dynamics of motorcycle at the initial stage itself using a numerical tool. To decide the handling characteristics it is very important to focus on the steering effort required at the handle bar by the rider, as it is the main control to study the ‘out of plane’ dynamics. To test the vehicle for steering performance, track radius and velocity were chosen as the variables to avoid the transient behavior and identify the key parameters at a faster rate. To study & investigate the steering effort influencing factors, an MBD numerical tool helped to solve the problem.
2015-04-14
Technical Paper
2015-01-0635
Changxin Wang, Wenku Shi, Zhijun Guo, Meilan Liu
Abstract For the roll vibration problem of a Truck, a 4-DOF roll vibration model of its front suspension system was built. According to dynamics theory, the complex modal vibration modes of the model were all obtained. At the same time, the frequency response functions of frame roll angle acceleration, the relative dynamic load of wheel and the suspension dynamic deflection were respectively presented. Then their characteristics were respectively researched. In the process of characteristic analysis, a new system parameter was proposed, which is the space ratio of the space between suspensions of left and right sides and the wheel track of the front axle (space ratio in short). At last, the influence of system parameters on the vibration transmission property was also reserached, which included the natural frequency of the frame, the damping ratio, the stiffness ratio, the mass ratio, the rotational inertia ratio and the space ratio.
2015-04-14
Technical Paper
2015-01-0628
Bin Li, Xiaobo Yang, Yunqing Zhang, James Yang
Vehicle tire performance is an important consideration for vehicle handling, stability, mobility, and ride comfort as well as durability. Significant efforts have been dedicated to tire modeling in the past, but there is still room to improve its accuracy. In this study, a detailed in-plane flexible ring tire model is proposed, where the tire belt is discretized, and each discrete belt segment is considered as a rigid body attached to a number of parallel tread blocks. The mass of each belt segment is accumulated at its geometric center. To test the proposed in-plane tire model, a full-vehicle model is integrated with the tire model for simulation under a special driving scenario: acceleration from rest for a few seconds, then deceleration for a few seconds on a flat-level road, and finally constant velocity on a rough road. The simulation results indicate that the tire model is able to generate tire/road contact patch forces that yield reasonable vehicle dynamic responses.
2015-04-14
Technical Paper
2015-01-0627
Xiaoguang Yang, Oluremi Olatunbosun, Daniel Garcia-Pozuelo, Emmanuel Bolarinwa
Abstract The development of intelligent tire technology from concept to application covers multi-disciplinary fields. During the course of development, the computational method can play a significant role in understanding tire behavior, assisting in the design of the intelligent tire prototype system and in developing tire parameters estimation algorithm, etc. In this paper, a finite element tire model was adopted for developing a strain-based intelligent tire system. The finite element tire model was created considering the tire's composite structure and nonlinear properties of its constituent materials, and the FE model was also validated by physical tests. The FE model is used to study tire strain characteristics by steady state simulation for straight line rolling, traction and braking, as well as cornering. Tire loading conditions were estimated by feature extraction and data fitting.
2015-04-14
Technical Paper
2015-01-0630
Guangzhong Xu, Nong Zhang, Holger Roser, Jiageng Ruan
Abstract The purpose of this paper is to present a concept of Hydro-Pneumatic Interconnected Suspension (HPIS) and investigate the unique property of the zero warp suspension stiffness. Due to the decoupling of warp mode from other modes, the road holding ability of the vehicle is maximized meanwhile the roll stability and ride comfort can be tuned independently and optimally without compromise. Ride comfort can be improved with reduced bounce stiffness and the progressive air spring rate can reduce the requirement of suspension deflection space. The roll stability can also be improved by increased roll stiffness. Vehicle suspension system modelling and modal analysis are carried out and compared with conventional suspension. The frequency response of tyres' dynamic load reveals that the proposed zero-warp-stiffness suspension enables the free articulation of front and rear axles at low frequency.
2015-04-14
Technical Paper
2015-01-0625
Manfred Baecker, Axel Gallrein, Michael Roller
Abstract The tire plays a fundamental role in the generation of acoustically perceptible driving noise and vibrations inside the vehicle. An essential part of these vibrations is induced by the road excitation and transferred via the tire into the vehicle. There are two basic ways to study NVH behavior: Simulations in time and frequency domains. The system can be simulated using a transient simulation method with the disadvantage of high simulation and process turnaround times. Alternatively, a linearization around a stationary state is performed and solved in frequency domain with fast numerical schemes. Modelling the tire transfer behavior in frequency domain requires special attention to the rotation of the tire. This paper shows the approach taken by the authors to include the transfer behavior in the frequency range up to 250 Hz from geometric road excitations to resulting spindle forces in frequency domain. Special care has been used in the modelling of local road excitations.
2015-04-14
Technical Paper
2015-01-0626
Adam C. Reid, Moustafa El-Gindy, Fredrik Oijer, David Philipps
Abstract The purpose of this research paper is to outline the procedure behind the parameter population of a wide-base rigid ring model. A rigid ring model is a mathematical representation of a highly non-linear FEA tire model that incorporates the characteristics and behaviour of a known physical tire. The rigid ring model parameters are determined using carefully designed virtual scenarios which will isolate for the parameter in question. Once all of the parameters have been calculated, for in-plane as well as out-of-plane parameters, a full rigid ring model can be populated. This model can also be modified to accommodate for a tire model simulated running over soft soils if necessary. For the purpose of this research however, the soft soil parameters were not determined. Once the rigid ring model is complete, the parameters can be used in a highly simplified virtual model to replicate the known behaviour of the tire but reduce the overall complexity of the full vehicle model.
2015-04-14
Technical Paper
2015-01-0620
Manoj Mahala, Anindya Deb, Clifford Chou
Abstract Idealized mathematical models, also known as lumped parameter models (LPMs), are widely used in analyzing vehicles for ride comfort and driving attributes. However, the limitations of some of these LPMs are sometimes not apparent and a rigorous comparative study of common LPMs is necessary in ascertaining their suitability for various dynamic situations. In the present study, the mathematical descriptions of three common LPMs, viz. quarter, half and full car models, are systematically presented and solved for the appropriate response parameters such as body acceleration, body displacement, and, pitch and roll angles using representative passive suspension system properties. By carrying out a comparison of the three stated LPMs for hump-type road profiles, important quantitative insights, not previously reported in the literature, are generated into their behaviors so that their applications can be judicious and efficient.
2015-04-14
Technical Paper
2015-01-1582
Jiawang Yong, Feng Gao, Nenggen Ding, Wei Wang, Xianrong Hu
Abstract Comparing with traditional braking systems of automobiles, the brake-by-wire (BBW) system has a faster dynamic response and is more suitable for applications that facilitate regenerative braking. As the two main categories of BBW systems, the well-known electro-hydraulic braking system and electro- mechanical braking system are not compact enough and their fail-safe function has always been a worrying aspect. A new BBW system called integrated braking system (IBS) by employing the hydraulic multiplex method was proposed in recent years. The IBS implements power-assisted braking and active braking by means of just an integrated unit. It can certainly be used for ABS, ASR and ESC systems for building up and reducing brake pressure. Presented in the paper is a new structure of IBS, which is mainly composed of a motor, ball screw, master cylinder and four 2/2-way valves.
2015-04-14
Technical Paper
2015-01-1586
Guirong Zhuo, Jin Wang, Fengbo Zhang
Abstract Accurate parameters of vehicle motion state are very important to the active safety of a vehicle. Currently the extended Kalman filter and unscented Kalman filter are widely used in estimation of the key state parameters, such as speed. In this situation, tire model must be used. The Magic Formula Tire Model is widely used in vehicle dynamics simulation because of its high versatility and accuracy. However, it requires a large number of parameters, which make the key state parameters of a real vehicle difficult to accurately obtain. Therefore, it is limited in real-time control of a vehicle. Firstly, the original Magic Formula Tire Model is simplified in this paper; then Jin Chi's Tire Model is introduced; thirdly, parameters of both the simplified Magic Formula and Jin Chi's Tire Model are identified using PSO (Particle Swarm Optimization) algorithm. Finally, Jin Chi's Tire Model is also used in parameters identification of experimental data.
2015-04-14
Technical Paper
2015-01-1574
Tao Sun, Yuping He
Abstract The phase-plane analysis technique has become a powerful tool for analyzing lateral stability of single-unit vehicles. Articulated vehicles, such as car-trailer combinations, consist of multiple vehicle units. Multi-unit vehicles exhibit unique dynamic features compared against single-unit vehicles. For example, a car-trailer may exhibit one of the three unstable motion modes, i.e., jack-knifing, trailer sway and rollover. Considering the distinguished configurations and dynamic features of articulated vehicles, it is questionable whether the phase-plane analysis method based on single-unit vehicles is applicable for analyzing the lateral stability of multi-unit vehicles. In order to address the problem, case studies are conducted to test the effectiveness of the phase-plane method for analyzing the lateral stability of a car-trailer combination, which is represented by a nonlinear vehicle model generated using the CarSim software package.
2015-04-14
Technical Paper
2015-01-1573
Guirong Zhuo, Hui Shen, Shenchen Wu, Yilin Ren
Abstract With the objective to regulate hydraulic pressure accurately by controlling high speed on-off valve (HSV), finite element models are parameterized based on measured parameters of an ABS hydraulic actuator unit (HCU). The data that reflects transient electromagnetic characteristics of HSV is selected with finite element numerical simulation. Taking full advantage of those data, accurate physical models of HSV are built with other parts of hydraulic braking system. Then a new system structure is proposed to control hydraulic pressure. Not only do simulation results show ideal control effect, but also hydraulic braking system can be controlled under arbitrary input signal. Accordingly, hydraulic braking force can achieve fine regulation. Finally, the hydraulic braking system is utilized to design antilock brake control system for four-wheel-drive electric vehicle with electro-hydraulic braking. That kind of system is established on the basis of hierarchical control structure.
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