scholarly journals A new approach to assess the influence of road roughness on driver speed behavior based on driving simulator tests

2016 ◽  
Vol 11 (2) ◽  
pp. 144-152 ◽  
Author(s):  
Mariano Pernetti ◽  
Mauro D’Apuzzo Mauro D’Apuzzo ◽  
Francesco Galante
Keyword(s):  
Driving Simulator ◽  
Experimental Studies ◽  
Vertical Vibration ◽  
The Other ◽  
Added Value ◽  
Published Data ◽  
Vehicle Speed ◽  
Safety Level ◽  
The Road ◽  
Road Roughness

Vehicle speed is one of main parameters describing driver behavior and it is of paramount importance as it affects the travel safety level. Speed is, in turn, affected by several factors among which in-vehicle vibration may play a significant role. Most of speed reducing traffic calming countermeasures adopted nowadays rely on vertical vibration level perceived by drivers that is based on the dynamic interaction between the vehicle and the road roughness. On the other hand, this latter has to be carefully monitored and controlled as it is a key parameter in pavement managements systems since it influences riding comfort, pavement damage and Vehicle Operating Costs. There is therefore the need to analyse the trade-off between safety requirements and maintenance issues related to road roughness level. In this connection, experimental studies aimed at evaluating the potential of using road roughness in mitigating drivers’ speed in a controlled environment may provide added value in dealing with this issue. In this paper a new research methodology making use of a dynamic driver simulator operating at the TEST Laboratory in Naples is presented in order to investigate the relationship between the driver speed behavior on one hand, and the road roughness level, road alignment and environment, vehicle characteristics on the other. Following an initial calibration phase, preliminary results seem fairly promising since they comply with the published data derived from scientific literature.

Study on the Dynamic Wheel Load of Multi-Axle Vehicle Based on Distribute Loading Weight

2010 ◽  
Vol 159 ◽  
pp. 35-40
Author(s):  
Zhong Hong Dong
Keyword(s):  
Dynamic Load ◽  
Influence Factors ◽  
Vehicle Speed ◽  
Tire Pressure ◽  
Wheel Load ◽  
The Road ◽  
Road Roughness ◽  
Tire Stiffness ◽  
On The Road

To study the dynamic wheel load on the road, a dynamic multi-axle vehicle mode has been developed, which is based on distribute loading weight and treats tire stiffness as the function of tire pressure and wheel load. Taking a tractor-semitrailer as representative, the influence factors and the influence law of the dynamic load were studied. It is found that the load coefficient increases with the increase of road roughness, vehicle speed and tire pressure, yet it decreases with the increase of axle load. Combining the influences of road roughness, vehicle speed, axle load and tire pressure, the dynamic load coefficient is 1.14 for the level A road, 1.19 for the level B road, 1.27 for the level C road, and 1.36 for the level D road.

Manoeuvring speed of a 6×6 autonomous vehicle using a database obtained from multi-body dynamic simulation

2009 ◽  
Vol 223 (8) ◽  
pp. 979-985 ◽  
Author(s):  
S-L Cho ◽  
K-C Yi ◽  
J-H Lee ◽  
W-S Yoo
Keyword(s):  
Dynamic Simulation ◽  
Autonomous Vehicle ◽  
Sensor Data ◽  
Vehicle Speed ◽  
The Road ◽  
Driving Speed ◽  
Road Roughness ◽  
Motion Speed ◽  
Vertical Accelerations ◽  
Vehicle Dynamic Simulation

For an autonomous vehicle that travels off-road, the driving speed is limited by the driving circumstances. To decide on a stable manoeuvring speed, the driving system should consider road conditions such as the height of an obstacle and road roughness. In general, an autonomous vehicle has many sensors to preview road conditions, and the information gathered by these sensors can be used to find the proper path for the vehicle to avoid unavoidable obstacles. However, sensor data are insufficient for determining the optimal vehicle speed, which could be obtained from the dynamic response of the vehicle. This paper suggests an algorithm that can determine the optimal vehicle speed running over irregular rough terrains such as when travelling off-road. In the determination of the manoeuvring speed, the vehicle dynamic simulation is employed to decide whether the vehicle response is within or beyond the prescribed limits. To determine the manoeuvring speed in real time, the dynamic simulation should be finished much more quickly than the real motion speed of the vehicle. In this paper, the equation of motion of the vehicle is derived in terms of the chassis local coordinates to reduce the simulation time. The velocity transformation technique, which combines the generality of Cartesian coordinates and the efficiency of relative coordinates, was combined with a symbolic computation to enhance further the computational efficiency. First the developed algorithm calculates the level of the previewed road roughness to determine the manoeuvring speed. Then, the maximum stable speed is judged against the database, which already has stored the maximum vertical accelerations as a function of the road roughness and vehicle speed.

scholarly journals Simultaneous Identification of Bridge Structural Damage and Moving Loads Using the Explicit Form of Newmark-β Method: Numerical and Experimental Studies

2021 ◽  
Vol 14 (1) ◽  
pp. 119
Author(s):  
Solmaz Pourzeynali ◽  
Xinqun Zhu ◽  
Ali Ghari Zadeh ◽  
Maria Rashidi ◽  
Bijan Samali
Keyword(s):  
Explicit Form ◽  
Structural Damage ◽  
Structural Parameters ◽  
Experimental Studies ◽  
Condition Assessment ◽  
Vehicle Speed ◽  
Moving Loads ◽  
Road Roughness ◽  
Bridge Structures ◽  
Simultaneous Identification

Bridge infrastructures are always subjected to degradation because of aging, their environment, and excess loading. Now it has become a worldwide concern that a large proportion of bridge infrastructures require significant maintenance. This compels the engineering community to develop a robust method for condition assessment of the bridge structures. Here, the simultaneous identification of moving loads and structural damage based on the explicit form of the Newmark-β method is proposed. Although there is an extensive attempt to identify moving loads with known structural parameters, or vice versa, their simultaneous identification considering the road roughness has not been studied enough. Furthermore, most of the existing time domain methods are developed for structures under non-moving loads and are commonly formulated by state-space method, thus suffering from the errors of discretization and sampling ratio. This research is believed to be among the few studies on condition assessment of bridge structures under moving vehicles considering factors such as sensor placement, sampling frequency, damage type, measurement noise, vehicle speed, and road surface roughness with numerical and experimental verifications. Results indicate that the method is able to detect damage with at least three sensors, and is not sensitive to sensors location, vehicle speed and road roughness level. Current limitations of the study as well as prospective research developments are discussed in the conclusion.

scholarly journals Evaluating the Dynamic Response of the Bridge-Vehicle System considering Random Road Roughness Based on the Moment Method

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Fan Feng ◽  
Fanglin Huang ◽  
Weibin Wen ◽  
Zhe Liu ◽  
Xiang Liu
Keyword(s):  
Random Process ◽  
Moment Method ◽  
System Response ◽  
Vehicle Speed ◽  
The Road ◽  
Bridge Span ◽  
Road Roughness ◽  
System Vibration ◽  
The Moment ◽  
The Impact

The bridge-vehicle interaction (BVI) system vibration is caused by the vehicles passing through the bridge. The road roughness has a great impact on the system vibration. In this regard, poor road roughness is known to affect the comfort of the vehicle crossing the bridge and aggravate the fatigue damage of the bridge. Road roughness is usually regarded as a random process in numerical calculation. To fully consider the influence of road roughness randomness on the response of the BVI system, a random BVI model was established. Thereafter, the random process of road roughness was expressed by Karhunen–Loeve expansion (KLE), after which the moment method was used to calculate the maximum probability value of the BVI system response. The proposed method has higher accuracy and efficiency than the Monte Carlo simulation (MCS) calculation method. Subsequently, the influences of vehicle speed, roughness grade, and bridge span on the impact factor (IMF) were analyzed. The results show that the road roughness grade has a greater impact on the bridge IMF than the bridge span and vehicle speed.

ŽVYRKELIU DULKETUMO MAŽINIMO TIRPALU “SAFECOTE” IR JO MIŠINIU SU CACL2 EKSPERIMENTINIAI TYRIMAI

2010 ◽  
Vol 18 (2) ◽  
pp. 145-153 ◽  
Author(s):  
Jolita Bradulienė ◽  
Saulius Vasarevičius
Keyword(s):  
Particulate Matter ◽  
Experimental Studies ◽  
Weather Conditions ◽  
Dry Season ◽  
Pvc Membrane ◽  
Vehicle Speed ◽  
Unpaved Road ◽  
The Road ◽  
Gravel Road

Unpaved gravel road dustiness causes a number of disadvantages both to vehicle drivers and to all those located in an unpaved road area. The “Safecote” solution and CaCl2 were chosen for an experimental road dustiness reduction. Experimental studies were carried out in the summer of 2007 and 2008. Four sections of an unpaved gravel road were selected, each 5 m long at 5 m intervals from one another. The selected sections were treated with various concentrations of “Safecote” solution (of summer 2007), and its mixtures with CaCl2(of summer 2008); also, one section was untreated for control sampling. The dust concentrations were measured in all the sections and the weather conditions were registered during measurings. Dependence of particulate matter concentrations (mg/m3) on vehicle speed and the distance from unpaved road was examined. The rainfall had no effect during the experiment because the road sections were covered with PVC membrane after each measurement. PVC membrane helps to keep relevant measuring results during a long dry season. Santrauka Žvyrkeliu dulketumas sukelia nemažai nepatogumu ir transporto priemoniu vairuotojams, ir visiems, esantiems netoli žvyrkelio aplinkos zonos. Nuo kelio kylančiu dulkiu kiekiui bent kiek sumažinti buvo pasirinktas tirpalas “Sa‐fecote” ir CaCl2. Eksperimentiniai tyrimai atlikti 2007 ir 2008 metu vasara. Tyrimams pasirinktos keturios 5 m žvyrkelio atkarpos, tarp kuriu buvo 5 m tarpas. Pasirinktos atkarpos apdorotos ivairios koncentracijos tirpalu “Safecote” (pirmaja vasara ‐ 2007 m.) ir jo mišiniais su CaCl2 (antraja vasara ‐ 2008 m.), o viena atkarpa palikta neapdorota (kontrolinis ruožas). Visose atkarpose matuota dulketumas bei oro salygas matavimo metu nusakantys parametrai. Nagrineta kietuju daleliu koncentracijos (mg/m3) priklausomybe nuo automobilio greičio bei atstumo nuo važiuojamosios kelio dalies. Eksperimento metu krituliu kiekis itakos neturejo, atkarpos buvo uždengtos plevele, kuri prieš matavimus būdavo nudengiama, o po ju vel uždengiama. Plevele naudota tam, kad tyrimu rezultatai būtu aktualūs ilgo sausojo sezono metu. Резюме Пыль гравийных дорог служит причиной многих проблем, возникающих как для водителей транспортных средств, так и для окружающей среды, расположеннoй в непосредственной близости от гравийных дорог. Для экспериментального уменьшения дорожной пыли были выбраны раствор „Safecote“ и CaCl2. Экспериментальные исследования проводились в летний период 2007 и 2008 гг. Были отобраны четыре сектора грунтовой дороги, каждые 5 метров в 5-метровом интервале. На отдельных секторах был разбрызган раствор „Safecote“ в разных концентрациях (летом 2007 г.), а также в смеси с CaCl2 (летом 2008 г.). Один сектор не был опрыскан для пробоотбора. Концентрация дорожной пыли была измерена во всех секторах, а также зарегистрированы погодные условия во время измерения. Изучена зависимость концентраций твердых частиц (мг/м3 ) от скорости движения автомобиля и расстояния от дороги. Во время эксперимента секторы были покрыты пленкой и таким образом защищены от осадков. До измерений и после них пленка находилась на экспериментальных рубежах. Пленка была использована для сохранения четкости результатов исследования во время долгосрочного сухого сезона.

scholarly journals Identifying Traffic Context Using Driving Stress: A Longitudinal Preliminary Case Study

Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2152 ◽  
Author(s):  
Olga Vl. Bitkina ◽  
Jungyoon Kim ◽  
Jangwoon Park ◽  
Jaehyun Park ◽  
Hyun K. Kim
Keyword(s):  
Electrodermal Activity ◽  
Physiological Responses ◽  
The Other ◽  
Vehicle Speed ◽  
Statistical Features ◽  
Traffic Jam ◽  
The Road ◽  
Traffic Conditions ◽  
The Relationship

Many previous studies have identified that physiological responses of a driver are significantly associated with driving stress. However, research is limited to identifying the effects of traffic conditions (low vs. high traffic) and road types (highway vs. city) on driving stress. The objective of this study is to quantify the relationship between driving stress and traffic conditions, and driving stress and road types, respectively. In this study, electrodermal activity (EDA) signals for a male driver were collected in real road driving conditions for 60 min a day for 21 days. To classify the levels of driving stress (low vs. high), two separate models were developed by incorporating the statistical features of the EDA signals, one for traffic conditions and the other for road types. Both models were based on the application of EDA features with the logistic regression analysis. City driving turned out to be more stressful than highway driving. Traffic conditions, defined as traffic jam also significantly affected the stress level of the driver, when using the criteria of the vehicle speed of 40 km/h and standard deviation of the speed of 20 km/h. Relevance to industry: The classification results of the two models indicate that the traffic conditions and the road types are important features for driving stress and its related applications.

scholarly journals Online Classification of Road Roughness Conditions with Vehicle Unsprung Mass Acceleration by Sliding Time Window

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Zhongxing Li ◽  
Wenhao Yu ◽  
Xiaoli Cui
Keyword(s):  
Time Window ◽  
Vehicle Speed ◽  
The Road ◽  
Physical Measurements ◽  
Online Classification ◽  
Power Spectral ◽  
Road Roughness ◽  
The Stability ◽  
Roughness Classification ◽  
Unsprung Mass

Suspension control systems are in need for more information of road roughness conditions to improve their performance under different roads. Existing methods of gauging road roughness are limited, and they usually involve visual inspections or special vehicles equipped with instruments that can gauge physical measurements of road irregularities. This paper proposes data collection for a period of a time from accelerometers fixed on unsprung mass and uses the mean square values of this datasets divided by vehicle speed to classify the roughness conditions of a section of a road. This approach is possible due to the existence of relationships between the power spectral densities of the road surface, unsprung mass accelerations via a transfer function, and vehicle speed. This paper gave the relationship between the resolution of road roughness classification and the length of time-window and suggestions about choosing the appropriate time-window length on the balance of road roughness resolution and classification delay. Moreover, to enhance the stability of classification, the influence of damping parameters of vehicle suspension on the classification output is studied, and a classification method of road roughness is proposed based on neural network and damping coefficient correction.

scholarly journals Vibration Analysis for Pendent Pedestrian Path of a Long-Span Extradosed Bridge

2019 ◽  
Vol 11 (17) ◽  
pp. 4664 ◽  
Author(s):  
Chuanjie Cui ◽  
Rujin Ma ◽  
Xiaohong Hu ◽  
Wuchao He
Keyword(s):  
Vibration Analysis ◽  
Vehicle Speed ◽  
Structure Form ◽  
Local Vibration ◽  
Maximum Acceleration ◽  
Turbulent Wind ◽  
The Road ◽  
Long Span ◽  
Road Roughness ◽  
Strong Winds

Pendent pedestrian path is a new structure form in long-span city bridges to satisfy vehicle passing demand and pedestrian passing demand simultaneously. For such design form, besides the traditional comfort problem caused by pedestrians, the vibration induced by upper passing vehicles and oncoming turbulent wind also cannot be ignored. In this research, the vibration characteristics of the pendent pedestrian path induced by pedestrians, upper vehicles, and turbulent wind are all investigated based on a designed long-span extradosed bridge. The results show that the design of the pedestrian path could satisfy the comfort demands comprehensively regardless of the local magnification effects of pedestrian path vibration. Reducing the spacing of the supported beam is meaningful for suppressing the local vibration effects. The road roughness of the upper pavement has significant effects on the maximum acceleration of pedestrian paths while the influence of the vehicle speed is relatively limited. An approximate quadratic relationship is observed between the buffeting-induced acceleration and the oncoming wind speed. Thus, the pedestrian path should be closed during strong winds.

Effects of Attachment Styles on the Experience of Equity in Heterosexual Couples Relationships

2003 ◽  
Vol 50 (4) ◽  
pp. 298-310 ◽  
Author(s):  
Ina Grau ◽  
Jörg Doll
Keyword(s):  
Attachment Theory ◽  
Attachment Style ◽  
Intimate Relationships ◽  
Attachment Styles ◽  
Experimental Studies ◽  
The Other ◽  
Heterosexual Couples ◽  
Secure Attachment ◽  
Dependent Variables ◽  
Equity Ratio

Abstract. Employing one correlational and two experimental studies, this paper examines the influence of attachment styles (secure, anxious, avoidant) on a person’s experience of equity in intimate relationships. While one experimental study employed a priming technique to stimulate the different attachment styles, the other involved vignettes describing fictitious characters with typical attachment styles. As the specific hypotheses about the single equity components have been developed on the basis of the attachment theory, the equity ratio itself and the four equity components (own outcome, own input, partner’s outcome, partner’s input) are analyzed as dependent variables. While partners with a secure attachment style tend to describe their relationship as equitable (i.e., they give and take extensively), partners who feel anxious about their relationship generally see themselves as being in an inequitable, disadvantaged position (i.e., they receive little from their partner). The hypothesis that avoidant partners would feel advantaged as they were less committed was only supported by the correlational study. Against expectations, the results of both experiments indicate that avoidant partners generally see themselves (or see avoidant vignettes) as being treated equitably, but that there is less emotional exchange than is the case with secure partners. Avoidant partners give and take less than secure ones.

Experiment role in the world music (based on the «The Road» album of the Ukrainian «Dakha Brakha» band)

2018 ◽  
pp. 215-227
Author(s):  
Iia Fedorova
Keyword(s):  
Folk Music ◽  
World Music ◽  
The Other ◽  
Modern Music ◽  
Musical Practice ◽  
The Road ◽  
Music Practice ◽  
The World ◽  
Binary Oppositions ◽  
Musical Practices

The main objective of this study is the substantiation of experiment as one of the key features of the world music in Ukraine. Based on the creative works of the brightest world music representatives in Ukraine, «Dakha Brakha» band, the experiment is regarded as a kind of creative setting. Methodology and scientific approaches. The methodology was based on the music practice theory by T. Cherednychenko. The author distinguishes four binary oppositions, which can describe the musical practice. According to one of these oppositions («observance of the canon or violation of the canon»), the musical practices, to which the Ukrainian musicology usually classifies the world music («folk music» and «minstrel music»), are compared with the creative work of «Dakha Brakha» band. Study findings. A lack of the setting to experiment in the musical practices of the «folk music» and «minstrel music» separates the world music musical practice from them. Therefore, the world music is a separate type of musical practice in which the experiment is crucial. The study analyzed several scientific articles of Ukrainian musicologists on the world music; examined the history of the Ukrainian «Dakha Brakha» band; presented a list of the folk songs used in the fifth album «The Road» by «Dakha Brakha» band; and showed the degree of the source transformation by musicians based on the example of the «Monk» song. The study findings can be used to form a comprehensive understanding of the world music musical practice. The further studies may be related to clarification of the other parameters of the world music musical practice, and to determination of the experiment role in creative works of the other world music representatives, both Ukrainian and foreign. The practical study value is the ability to use its key provisions in the course of modern music in higher artistic schools of Ukraine. Originality / value. So far, the Ukrainian musicology did not consider the experiment role as the key one in the world music.

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