Evaluation on Analytical Tire Models for Vehicle Vertical Vibration Simulation Using Virtual Tire Testing Method

1999 ◽  
Author(s):  
Jun Sui ◽  
John Hirshey
Keyword(s):  
Vertical Vibration ◽  
Testing Method ◽  
Tire Testing ◽  
Vibration Simulation ◽  
Tire Models

Development and Design of a Cost-Efficient Tire Mechanics Testing Apparatus

2008 ◽  
Author(s):  
Brendan J. Chan ◽  
Corina Sandu ◽  
Erin Hissong ◽  
Steve Southward
Keyword(s):  
Academic Research ◽  
Vertical Load ◽  
Test Apparatus ◽  
Current Configuration ◽  
Physical Limitations ◽  
Tire Testing ◽  
Cost Efficient ◽  
Soil Bin ◽  
Tire Models ◽  
Accuracy And Repeatability

Most tire models need experimentally obtained data as input for simulation purposes. The study of tire mechanics requires the accuracy and repeatability of a controlled environment. However, the accessibility and cost of tire testing machines make it prohibitive for exploring tire mechanical properties for academic studies. Moreover, most industrial tire testing machines are designed for general tire testing, and would require an extensive amount of time and resources to adapt for academic research. To study tire mechanical behavior for modeling purposes, a tire mechanics test apparatus has been developed at the Center for Vehicle Systems and Safety (CVeSS), Virginia Tech. The tire mechanics test apparatus has been designed as an interchangeable attachment to an existing modular quarter car test rig developed at the Institute for Advanced Learning and Research (IALR) in Danville, Virginia, to save on cost, as well as to maintain repeatability of testing. The physical limitations of maximum tire vertical load for various tire testing machines are also among the main motivations for developing the tire mechanics test apparatus. The current configuration of the tire mechanics test apparatus provides the capability to study the vertical load - deflection characteristics of the tire, as well as the static footprint of the tire under various vertical loads. Future planned enhancements to the setup include the addition of a soil bin and an instrumented rolling drum for tire shear force studies.

Tire Lateral Vibration Considerations in Vehicle-Based Tire Testing

2019 ◽  
Vol 47 (3) ◽  
pp. 211-231
Author(s):  
Anton Albinsson ◽  
Fredrik Bruzelius ◽  
P. Schalk Els ◽  
Bengt Jacobson ◽  
Egbert Bakker
Keyword(s):  
Lateral Force ◽  
Testing Procedure ◽  
Operating Conditions ◽  
Tire Model ◽  
Root Cause ◽  
Tire Force ◽  
Model Parameterization ◽  
Tire Testing ◽  
Suspension Model ◽  
Tire Models

ABSTRACT Vehicle-based tire testing can potentially make it easier to reparametrize tire models for different road surfaces. A passenger car equipped with external sensors was used to measure all input and output signals of the standard tire interface during a ramp steer maneuver at constant velocity. In these measurements, large lateral force vibrations are observed for slip angles above the lateral peak force with clear peaks in the frequency spectrum of the signal at 50 Hz and at multiples of this frequency. These vibrations can lower the average lateral force generated by the tires, and it is therefore important to understand which external factors influence these vibrations. Hence, when using tire models that do not capture these effects, the operating conditions during the testing are important for the accuracy of the tire model in a given maneuver. An Ftire model parameterization of tires used in vehicle-based tire testing is used to investigate these vibrations. A simple suspension model is used together with the tire model to conceptually model the effects of the suspension on the vibrations. The sensitivity of these vibrations to different operating conditions is also investigated together with the influence of the testing procedure and testing equipment (i.e., vehicle and sensors) on the lateral tire force vibrations. Note that the study does not attempt to explain the root cause of these vibrations. The simulation results show that these vibrations can lower the average lateral force generated by the tire for the same operating conditions. The results imply that it is important to consider the lateral tire force vibrations when parameterizing tire models, which does not model these vibrations. Furthermore, the vehicle suspension and operating conditions will change the amplitude of these vibrations and must therefore also be considered in maneuvers in which these vibrations occur.

scholarly journals Vibration transmission simulation model of a seated vehicle passenger

2021 ◽  
Vol 2120 (1) ◽  
pp. 012009
Author(s):  
I Ho ◽  
N Z Abu Bakar
Keyword(s):  
Simulation Model ◽  
Human Body ◽  
Ride Comfort ◽  
Real Life ◽  
Vertical Vibration ◽  
Suspension System ◽  
Human Body Model ◽  
Peak Displacement ◽  
Moving Vehicle ◽  
Vibration Simulation

Abstract The paper presents development of vertical vibration simulation for a seated passenger in a moving vehicle is resulting from the bounce effect of the vehicle under various conditions. Although extensive research has been conducted in this field of study, the existing analysis were conducted on either the suspension of vehicle or the human body and not both. In this paper, the simulation model consists of three sub-systems, namely, vehicle suspension, seat suspension and human body model in which the vertical vibration is transmitted. By incorporating these sub-systems into the simulation, a correlation between mechanical and biological aspects can be formed between the three sub-systems. The transmission of vertical vibration in the validated simulation model provides a more realistic approach which can result to a better comparison to the real-life scenario. Parametric analysis of passive suspension system shows that lower mass ratio, higher stiffness ratio and lower damping coefficient results in better ride comfort. The incorporation of variable damper into the suspension system shows significant improvement in settling time, peak displacement and velocity, lesser discomfort rating and higher safety in passenger body.

scholarly journals Laboratory Evaluation of a Vertical Vibration Testing Method for an SMA-13 Mixture

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4409
Author(s):  
Yingjun Jiang ◽  
Jiangtao Fan ◽  
Jinshun Xue ◽  
Changqing Deng ◽  
Yong Yi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Strength ◽  
Heavy Traffic ◽  
Asphalt Mixture ◽  
Vertical Vibration ◽  
Laboratory Evaluation ◽  
Vibration Testing ◽  
Testing Method ◽  
Vibration Compaction ◽  
Compaction Time

In order to simulate the on-site compaction conditions of a Stone Matrix Asphalt (SMA) mixture, The Vertical Vibration Testing Method (VVTM), Superpave Gyratory Compactor (SGC), and Marshall method are used to test the SMA-13 mixture, and the physical and mechanical properties of the asphalt mixture designed by these three methods are tested. Subsequently, the influences of the molding method on the mechanical properties are compared. The influence of vibration compaction time on the volume parameters of the SMA mixture is studied. Following the heavy traffic compaction standards, the vibration compaction time of the SMA mixture is determined. The results show that the densities of the heavy Marshall specimen, VVTM specimen, and SGC specimen are 1.018 times, 1.019 times, and 1.015 times greater than that of the standard Marshall specimen, respectively. The passing rate of the 4.75 mm aggregate of the standard Marshall specimen is 29.9%, and that of the VVTM specimen and SGC specimen is 31.1% and 30.5%, respectively, while that of the heavy Marshall specimen is 34.5%. The mechanical strength of the specimen can be greatly improved as the density increases. On the other hand, by the same compaction work, the mechanical strength of the VVTM specimens can be increased by at least 7% compared with the heavy Marshall specimen. The mechanical strength of the VVTM specimen is increased by at least 22% compared with the standard Marshall specimen. The results also show that under the optimal asphalt-aggregate ratio and the same compaction work, the compressive strength and shear strength of the VVTM specimens are increased by at least 6% and 9%, respectively, compared with the Marshall specimens. In summary, the performance of the asphalt mixture designed by the VVTM is superior, providing a wider choice for future asphalt mixture design.

Standardization in Tire Modeling and Tire Testing — TYDEX Workgroup, TIME Project

1999 ◽  
Vol 27 (3) ◽  
pp. 188-202 ◽  
Author(s):  
J. J. M. van Oosten ◽  
H.-J. Unrau ◽  
A. Riedel ◽  
E. Bakker
Keyword(s):  
Measurement Data ◽  
Testing Procedure ◽  
International Colloquium ◽  
Vehicle Modeling ◽  
Testing Procedures ◽  
Research Organizations ◽  
Tire Modeling ◽  
Tire Testing ◽  
To Come ◽  
Tire Models

Abstract As a result of the 1st International Colloquium on Tire Models for Vehicle Dynamics Analysis in 1991, the international TYDEX Workshop working group was established. This workshop concentrated on the standardization of the exchange of tire measurement data and the interface between tire and vehicle models in order to improve the communications between vehicle manufacturers, suppliers, and research organizations. The development and knowledge of tire behavior is of great importance to both the tire and vehicle industries and will be intensified. Therefore the TYDEX Workshop received great interest from all parties to come to some kind of standardization. In the two expert groups, one of which focused on Tire Measurements — Tire Modeling and the other on Tire Modeling — Vehicle Modeling, the TYDEX-Format and the standard tire interface have been developed, which will be explained in this paper. Furthermore, a short overview of the European TIME project aiming at a standard tire testing procedure will be given, which is reliable and consistent with realistic driving conditions. Standard testing procedures are some of the important consequences of the TYDEX Workshop.

scholarly journals Experimental Comparison of Field and Accelerated Random Vertical Vibration Levels of Stacked Packages for Small Parcel Delivery Shipments

2021 ◽  
Vol 11 (7) ◽  
pp. 2927
Author(s):  
Bence Molnár ◽  
Péter Böröcz
Keyword(s):  
Vertical Vibration ◽  
Experimental Comparison ◽  
Shopping Malls ◽  
Time Data ◽  
Worst Case ◽  
Power Spectral ◽  
Online Stores ◽  
Vibration Simulation ◽  
To Receive ◽  
Phase Motion

In the last decade, there has been a significant increase in parcel delivery shipments all over the world due to online stores and consumer demand to receive the products in a shorter period of time. It is especially true when situations like COVID-19 limits personal purchases in shopping malls as well as grocery and pharmaceutical stores. This often means that courier operators try to deliver packages utilizing vehicles with racks or shelves, which during the COVID-19 epidemic are not there anymore. This study measured the vertical vibration levels that occur in stacked parcels during express delivery versus the simulation technique in the laboratory. The goal of this paper was to measure and compare the vibration levels between laboratory practice and field transportation. For the measurement a three-layer stacked unit was built to observe the vibration levels on different road conditions in a parcel delivery vehicle and ASTM vibration profile (ASTM International). Then the measured acceleration-time data were analyzed in terms of power spectral densities (PSD) and the presented statistical data provided an understanding of the variability of intensity in different levels in stacked unit. The results showed that the vibration level increases in the stacked load upwards and with worse road conditions, but even in the worst case it did not reach those vibration levels that the laboratory test showed. Moreover, the layers of the stacked unit are in out-of-phase motion in the field, while the stacked unit in the vibration simulation usually is in-phase motion. Results indicate that the proposed vibration simulation does not correlate well with typical field vibration. This is fundamentally true as during a forced vibration created by a single-axis shaker, do not account for additional inputs occurring simultaneously creating an off-balance to the loads and as a result are less severe than simulated conditions. These findings are limited to single axis vibration simulation and unsecured loads.

The present state of aspirin and clopidogrel resistance

2009 ◽  
Vol 29 (03) ◽  
pp. 285-290 ◽  
Author(s):  
K. E. Guyer
Keyword(s):  
Diagnostic Tests ◽  
Arterial Thrombosis ◽  
Cardiovascular Events ◽  
Treatment Success ◽  
Antiplatelet Agents ◽  
Antiplatelet Drug ◽  
Coronary Syndrome ◽  
Testing Method ◽  
Pharmacological Response ◽  
Platelet Physiology

SummaryAntiplatelet therapy has demonstrated significant clinical benefit in the treatment of acute coronary syndrome. However, as with any treatment strategy it has been unable to prevent all cardiovascular events. This is far from surprising when considering the complexity of arterial thrombosis and more specifically platelet physiology. This lack of treatment success has provoked the introduction of various diagnostic tests and testing platforms with the intent of guiding and optimizing clinical treatment. Such tests have resulted in the generation of clinical data that suggest suboptimal response to antiplatelet agents such as aspirin and clopidogrel.In the case of both aspirin and clopidogrel, this suboptimal response has been termed resistance. Drug resistance would imply a lack of pharmacological response that has not been specifically investigated in many of the clinical studies performed to date. Rather, the term resistance has been used to describe various facets of platelet activation and aggregation relative to the testing method. Many of these measured parameters are not addressed in the therapeutic intent of the antiplatelet drug in question.

Pengujian pada Aplikasi Penggajian Pegawai dengan menggunakan Metode Blackbox

2020 ◽  
Vol 5 (1) ◽  
pp. 61
Author(s):  
Vadlan Febrian ◽  
Muhamad Rizki Ramadhan ◽  
Muhammad Faisal ◽  
Aries Saifudin
Keyword(s):  
Data Entry ◽  
Black Box ◽  
Application Form ◽  
Value Analysis ◽  
Test Function ◽  
Testing Method ◽  
Black Box Testing ◽  
Sample Testing ◽  
Testing Techniques ◽  
Program Error

In this employee payroll application, if there is an error program there will be a loss for employees and the company. Losses for employees, if this application program error occurs then the salary reduction will experience delays due to the difficulty in the process of calculating employee salaries and employees will be late in receiving salaries. Losses for the company, if there is an error program in this application, the company will suffer losses if the employee wants a salary reduction quickly but the company cannot calculate quickly and accurately. In solving this problem, the authors use the black box testing method. Black box testing method is a test that sees the results of execution through test data and ensures the function of the software. Black box testing method has several testing techniques, namely Sample Testing, Boundary Value Analysis, Equivalence Partitions and others. From the testing techniques that have been mentioned, we use the Equivalence Partitions testing technique. Equivalence Partitions are tests that refer to data entry on the employee payroll application form, input will be tested and then put together based on the test function, both valid and invalid values. The expected results of this test are a payroll system for employees who are computerized, have standard rules in the process of developing the program so that it is easy to develop and maintain, and can minimize errors in processing salary calculations for employees.

Analisis Kesalahan Penggunaan Jinyici dalam Membuat Kalimat Bahasa Mandarin pada Mahasiswa Semester VI Angkatan 2014 Prodi Pendidikan Bahasa Mandarin Universitas Negeri Semarang

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Siti Soleha ◽  
Fansi Onita Santoso ◽  
Zaim Elmubarok
Keyword(s):  
Language Education ◽  
Quantitative Approach ◽  
Education Department ◽  
Testing Method ◽  
Mandarin Language

Penelitian ini bertujuan untuk mengetahui besar persentase kesalahan penggunaan (jìnyìcí), mengetahui kesalahan apa saja yang dilakukan mahasiswa, menentukan cara untuk membedakan penggunaan (jìnyìcí) dan merumuskan solusi yang dapat dilakukan untuk mengurangi kesalahan penggunaan (jìnyìcí) tersebut. Pendekatan penelitian yang dilakukan adalah deskriptif kuantitatif. Populasi dan sampel pada penelitian ini adalah mahasiswa semester VI angkatan 2014 Prodi Pendidikan Bahasa Mandarin Universitas Negeri Semarang sebanyak 25 mahasiswa. Teknik pengumpulan data dilakukan dengan metode dokumentasi dan metode tes. Berdasarkan hasil penelitian diketahui persentase kesalahan penggunaan (jìnyìcí) adalah sebesar 28,4%. Kesalahan tersebut tergolong pada tingkat rendah, namun ada beberapa kesalahan yang perlu lebih diperhatikan yaitu kesalahan dalam penggunaan fungsi tata bahasa dan kesalahan dalam memahami makna. Cara membedakan penggunaan (jìnyìcí) dapat dilakukan mahasiswa dengan mempelajari fungsi tata bahasa kosakata (jìnyìcí) dan memahami makna kosakata (jìnyìcí). Solusi yang dapat dilakukan adalah mempelajari fungsi tata bahasa kosakata (jìnyìcí) secara keseluruhan dengan benar, memahami makna kosakata (jìnyìcí) secara spesifik, dan memperbanyak latihan membuat kalimat menggunakan kosakata (jìnyìcí).This study aims to identify mistake percentage in using (jìnyìcí), identify what mistakes conducted by students, determine how to differentiate the usage of (jìnyìcí), and formulate solution to reduce mistake in using (jìnyìcí). This study uses descriptive-quantitative approach. There are 25 sixth students of Mandarin Language Education Department in Universitas Negeri Semarang as population and sample. In addition, data is collected by documentation and testing method. Based on the analysis, there is 28,4% of mistake in using (jìnyìcí). This finding is categorized as low. However, there are some mistakes that need to be noted. For instance, mistake in using grammar and interpreting meaning. Furthermore, (jìnyìcí) can be differentiate by studying grammar of (jìnyìcí) and understand the meaning of (jìnyìcí). Finally, it is recommended to study the grammar of (jìnyìcí), specifically understand the meaning of (jìnyìcí) and increase the exercise to make sentences using (jìnyìcí).

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