scholarly journals Bump Modeling and Vehicle Vertical Dynamics Prediction

2014 ◽  
Vol 6 ◽  
pp. 736576 ◽  
Author(s):  
Daniel Garcia-Pozuelo ◽  
Antonio Gauchia ◽  
Ester Olmeda ◽  
Vicente Diaz
Keyword(s):  
Traffic Safety ◽  
Vehicle Dynamics ◽  
Pedestrian Safety ◽  
Simulation Program ◽  
Motor Vehicles ◽  
Vehicle Speed ◽  
Legal Limit ◽  
Different Types ◽  
Proper Design

During a journey, motor vehicles are subjected to different types of irregularities in the pavement. Some of these irregularities are introduced for a specific purpose over a stretch of road to slow down the vehicle at certain road points. However, the influence of installed speed bumps reveals certain additional effects which must be deeply analyzed to ensure vehicle and pedestrian safety. In some cases, it has been found that even when driving over transverse bands at a speed below the legal limit, the vehicle is damaged or tires lose grip with the pavement, precluding any kind of braking or turning maneuvers. Such phenomena indicate that either this element is not properly sized or the location is not appropriate, becoming counterproductive for traffic safety. In order to analyze the influence of these irregularities on the different components of the vehicle and its occupants, a simulation program with MatlabTM has been developed. The validated developed tool takes into account several aspects of the vehicle dynamics, bump geometry, and vehicle speed. The proposed tool provides the best possible information to establish a set of guidelines for the proper design and installation of speed bumps in different roads.

Influence of Speed Bumps Design on Vehicle Safety

2011 ◽  
Author(s):  
D. Garci´a-Pozuelo ◽  
E. Olmeda ◽  
A. Gauchi´a ◽  
V. Di´az
Keyword(s):  
Traffic Safety ◽  
Experimental Testing ◽  
Simulation Software ◽  
Motor Vehicles ◽  
Vehicle Safety ◽  
Vehicle Velocity ◽  
Dynamic Forces ◽  
Different Types ◽  
Proper Design ◽  
Real Vehicle

During a journey motor vehicles are forced to overcome different types of irregularities in the pavement. Such irregularities can be random or introduced for a specific purpose, such as asphalt protrusions and transversal bands of rubber, which have been installed into all sorts of avenues and roads open to traffic. Generally, these elements are included in a stretch of road to slow down the vehicle velocity at certain sites, such as pedestrian crossings. However, the influence of speed bumps installed shows other additional effects which must be studied to ensure the safety of vehicles and pedestrians. In some cases, it is found that, passing over ridges and transverse bands at a speed below the limit defined by law, the vehicle is damaged or the tires lose grip with the pavement, precluding any kind of braking or turning maneuvers. Such phenomena indicate that this element is not properly sized, or the placement is not appropriate, becoming counterproductive for traffic safety. In spite of the importance of these consecuences derivated from these elements they haven’t been studied deeply enough and there are very few paper about this subject. In order to analyze the actions generated by the overcome of these irregularities on the different components of the vehicle and its occupants, the problem has been studied not only using computer simulation but also by means of experimental testing on a real vehicle where accelerometers were installed in order to check the severity of the bumps. CarSimTM has been the simulation software used to calculate vehicle dynamic forces on the tires and suspension system and the accelerations and displacements that are applied to the vehicle. To characterize the behavior of a vehicle when is driven over one of these obstacles, it is necessary to study several parameters such as: speed, geometry and dimensions of the bump, and the type of vehicle and its suspension. From this information it is possible to establish a set of guidelines for the proper design and installation of speed bumps in different roads.

Evaluation of Shared-Use Facilities for Bicycles and Motor Vehicles

1997 ◽  
Vol 1578 (1) ◽  
pp. 111-118 ◽  
Author(s):  
David L. Harkey ◽  
J. Richard Stewart
Keyword(s):  
Motor Vehicle ◽  
Separation Distance ◽  
Urban Environments ◽  
Operating Conditions ◽  
Motor Vehicles ◽  
Vehicle Speed ◽  
Rural And Urban ◽  
Different Types ◽  
Measures Of Effectiveness ◽  
Bicycle Lane

This study was conducted for the Florida Department of Transportation with an objective of evaluating the safety and utility of shared-use facilities to provide engineers and planners comprehensive results that can be used in planning, designing, and constructing roadways to be shared by motorists and bicyclists. The results were developed from an analysis of observations of bicyclists and motorists interacting on different types of roadways. The evaluation included roadways with wide curb lanes, bicycle lanes, and paved shoulders. Locations from both rural and urban environments were included and varied in terms of motor-vehicle speed, traffic volume, lane width, and number of lanes. The operational measures of effectiveness used in evaluating the different types of facilities included ( a) lateral placement of the bicyclist, ( b) lateral placement of the motor vehicle, ( c) separation distance between the bicycle and the motor vehicle, and ( d) encroachments by the motorist or bicyclist during the passing maneuver. Results of the analysis showed that the type of facility (wide curb lane versus bicycle lane versus paved shoulder) does have a significant effect on the separation distance between bicyclists and motor vehicles; this distance ranged from 1.80 to 1.95 m (5.9 to 6.4 ft). The findings also indicated that paved shoulders and bicycle lanes generally result in similar interactions between motorists and bicyclists and that when compared with wide curb lanes they offer some distinct advantages to both user groups. The results also indicated that bicycle lanes as narrow as 0.92 m (3 ft) provide sufficient space for motorists and bicyclists to interact safely. At the same time, a 1.22-m (4-ft) wide bicycle lane tended to optimize operating conditions because there were very few differences in the measures of effectiveness when 1.22-m lanes were compared with wider lanes.

scholarly journals Effectiveness of Pedestrian Safety Service Provision Using Sensing Technology

2021 ◽  
Vol 13 (16) ◽  
pp. 9333
Author(s):  
Ki-Man Hong ◽  
Sang-Hoon Son ◽  
Jong-Hoon Kim
Keyword(s):  
Traffic Safety ◽  
Child Protection ◽  
Traffic Accidents ◽  
Pedestrian Safety ◽  
Vehicle Speed ◽  
Protection Zone ◽  
Road Section ◽  
Sensing Technology ◽  
Approach Speed ◽  
Pedestrian Traffic

In this study, we describe the results of an analysis of the effectiveness of providing pedestrian safety services, in terms of reducing pedestrian traffic accidents. We conducted our analysis by investigating the speed of vehicles at two different demonstration points, where the same system and service were provided. For this purpose, we selected a child protection zone and a point on a general road section where a raised crossing is installed. We conducted vehicle speed surveys at the point adjacent to the crosswalk and the points where the driver is expected to be fully provided with information, in order to examine the change in vehicle approach speed, depending on the provision of the service. Overall, the analysis showed that the vehicle’s speed at the point and approaching speed decreased when the pedestrian safety service was provided; however, the effect was more pronounced in the child protection zone, considering the characteristics of the demonstration points. From these results, we conclude that it is necessary to provide services and develop guidelines considering the surrounding environment, such as traffic safety facilities and road safety facilities, according to the characteristics and classification of each point, in order to provide efficient pedestrian safety services.

scholarly journals Lane Departure Warning Estimation Using Yaw Acceleration

2020 ◽  
Vol 11 (1) ◽  
pp. 102-111
Author(s):  
Em Poh Ping ◽  
J. Hossen ◽  
Wong Eng Kiong
Keyword(s):  
Vehicle Dynamics ◽  
Dynamic Responses ◽  
Dynamics Simulation ◽  
Steering Wheel ◽  
Mathematical Representation ◽  
Vehicle Speed ◽  
Lane Departure Warning ◽  
Model Based ◽  
Lane Departure ◽  
Proposed Model

AbstractLane departure collisions have contributed to the traffic accidents that cause millions of injuries and tens of thousands of casualties per year worldwide. Due to vision-based lane departure warning limitation from environmental conditions that affecting system performance, a model-based vehicle dynamics framework is proposed for estimating the lane departure event by using vehicle dynamics responses. The model-based vehicle dynamics framework mainly consists of a mathematical representation of 9-degree of freedom system, which permitted to pitch, roll, and yaw as well as to move in lateral and longitudinal directions with each tire allowed to rotate on its axle axis. The proposed model-based vehicle dynamics framework is created with a ride model, Calspan tire model, handling model, slip angle, and longitudinal slip subsystems. The vehicle speed and steering wheel angle datasets are used as the input in vehicle dynamics simulation for predicting lane departure event. Among the simulated vehicle dynamic responses, the yaw acceleration response is observed to provide earlier insight in predicting the future lane departure event compared to other vehicle dynamics responses. The proposed model-based vehicle dynamics framework had shown the effectiveness in estimating lane departure using steering wheel angle and vehicle speed inputs.

scholarly journals Contrasting Perspectives on the Comfort and Safety of Pedestrians Interacting with Other Road Users

2021 ◽  
Vol 2675 (3) ◽  
pp. 33-43
Author(s):  
Alexander Bigazzi ◽  
Gurdiljot Gill ◽  
Meghan Winters
Keyword(s):  
Traffic Safety ◽  
Injury Risk ◽  
Road User ◽  
Motor Vehicles ◽  
Advisory Group ◽  
User Interactions ◽  
The Public ◽  
Road Users ◽  
Expert Assessments ◽  
Sample Representation

Assessments of interactions between road users are crucial to understanding comfort and safety. However, observers may vary in their perceptions and ratings of road user interactions. The objective of this paper is to examine how perceptions of yielding, comfort, and safety for pedestrian interactions vary among observers, ranging from members of the public to road safety experts. Video clips of pedestrian interactions with motor vehicles and bicycles were collected from 11 crosswalks and shown to three groups of participants (traffic safety experts, an engaged citizen advisory group, and members of the general public) along with questions about yielding, comfort, and risk of injury. Experts had similar views of yielding and comfort to the other two groups, but a consistently lower assessment of injury risk for pedestrians in the study. Respondent socio-demographics did not relate to perceptions of yielding, comfort, or risk, but self-reported travel habits did. Respondents who reported walking more frequently rated pedestrian comfort as lower, and respondents who reported cycling more frequently rated risk as lower for pedestrian interactions with both motor vehicles and bicycles. Findings suggest small groups of engaged citizens can provide useful information about public perspectives on safety that likely diverge from expert assessments of risk, and that sample representation should be assessed in relation to travel habits rather than socio-demographics.

scholarly journals Drunk Drivers’ Willingness to Use and to Pay for Designated Drivers

2021 ◽  
Vol 13 (10) ◽  
pp. 5362
Author(s):  
Rong-Chang Jou ◽  
Li-Wun Syu
Keyword(s):  
Traffic Safety ◽  
Family Background ◽  
Drunk Driving ◽  
Motor Vehicles ◽  
Drinking Habits ◽  
Car Accidents ◽  
Drunk Drivers ◽  
Double Hurdle ◽  
The Government ◽  
Willingness To Use

While drunk driving accidents, which are a serious problem in Taiwan, have decreased in recent years, cases of drunk driving continue to emerge endlessly, and are a source of traffic risks even when the accidents cause no injuries. In order to prevent drunk driving and reduce car accidents, the government has made laws stricter, and has vigorously promoted “designated drivers”. As the concept of designated drivers is not common in Taiwan, this study mainly explores drunk drivers’ understanding of designated drivers in Nantou County and Taichung City, and investigates the willingness of drunk drivers to use and to pay for designated driving services. This study conducted a questionnaire survey on the drunk drivers of the drunk driving and traffic safety training course held at the Motor Vehicles Office. Double-hurdle and tobit models were applied to investigate the issues mentioned above. According to the test results, the tobit model was superior to the double-hurdle model. The estimation results indicated that distance, age, income, family conditions, and drinking habits influence the willingness to use and to pay for designated drivers. Gender, age, family background, and experience in designated driving cause differences in the willingness to use designated drivers in the two regions. It is expected that the conclusion of this study could provide a direction and reference for the future improvement of designated driving services.

scholarly journals Skew Superelevation Edge Rounding Design Improving Riding Comfort on Freeways

2019 ◽  
Vol 2673 (1) ◽  
pp. 343-357
Author(s):  
Konstantinos Apostoleris ◽  
Basil Psarianos ◽  
Ioannis-Alexandros Choupas ◽  
Vassilios Matragos
Keyword(s):  
Road Safety ◽  
Simulation Program ◽  
Heavy Vehicles ◽  
Parameter Change ◽  
Vehicle Simulation ◽  
Different Types ◽  
Vertical Accelerations ◽  
Design Speed ◽  
High Level ◽  
Traveling Speed

Skew superelevation has proven to be an efficient pavement constructional measure to address hydroplaning phenomena under specific critical superelevation runoff designs. However, this technique has raised concerns about user’s comfort when driving over the skewed edge of the pavement, especially for heavy vehicles and when the traveling speed is higher than the design speed. This paper aims to evaluate the driving comfort outcome on an improved skew superelevation design, where a rounding of the skew edge has been applied. This is achieved through the use of a simulation program which examines the vehicle and driver behavior when passing over it. The simulation program estimates many parameters including the lateral and vertical accelerations ( Gy and Gz) imposed on both elements, the vehicle and the driver. This evaluation is made for different alignment designs provided in the freeway design and for a broad range of especially high velocities ranging from 80 to 160 km/h (50–100 mph), as well as for different types of heavy vehicles. Also, the influence on the above parameters has been investigated in respect of the distance between two consecutive skew superelevations, concerning cases of entering and exiting a simple, low-length curve. The outcomes are classified in order to evaluate their variability as affected by each parameter change (speed, geometry, vehicle). Simulation results are compared with thresholds, as provided in the international literature, to ensure driver comfort and a high level of road safety.

Road Engineering Optimization Based on Driving Reaction

2013 ◽  
Vol 579-580 ◽  
pp. 841-844
Author(s):  
Zhao Cao ◽  
Xiao Wu ◽  
Qing Yang
Keyword(s):  
Traffic Safety ◽  
Safety Issue ◽  
Heart Beat ◽  
Driving Safety ◽  
Response Analysis ◽  
Vehicle Speed ◽  
Force Coefficient ◽  
Slope Length ◽  
Road Engineering ◽  
Positive Correlation

With the increasingly outstanding of the traffic safety issue, the human factors in People-Vehicle-Road System are being emphasized gradually. Takes Jinhua suburb asphalt mountain road (two-lane, multiple steep slopes) for example, this study focuses on road engineering response analysis on driving reaction, design optimization of road engineering base on driving response. A driver over 3 driving years steered 5-seat car in 4 kilometers long experimental road, kept the vehicle speed (V) under 40km/h. Heartbeat rate of the driver was monitored by dynamic Holter through driving process. The analysis shows that there is a linear positive correlation between Heart beat growth rate (Ni) and V, a nearly positive correlation between lateral force coefficient (μ) and Ni, and nearly inversely proportional between plane curve radius (R) and slope (i). It should decrease R appropriately when road slope (i) much sharply in road alignment design. There is a polynomial relation between Ni, V and R. As R increases, both Ni and V reduce firstly, and then rise. When R ranges from 240 to 500 meter, stress gradually ease; while R exceeds 500 meter, driving reaction tension gradually rise. R<550 m, i <6% and slope length under 300 m in the experimental road. When instructional speed <40km/h, then Ni was 30.2% and μ was 0.25. Its benefit for driving safety to keep drivers in appropriate tension in such situation.

Research on Safety Vehicle Distance Recognition Based on Stereo Vision and DSP

2013 ◽  
Vol 333-335 ◽  
pp. 805-810 ◽  
Author(s):  
Rong Bao Chen ◽  
Ning Li ◽  
Hua Feng Xiao ◽  
Wei Hou
Keyword(s):  
Stereo Vision ◽  
Traffic Safety ◽  
Traffic Accidents ◽  
Intelligent Transportation ◽  
Research Area ◽  
Measurement Range ◽  
Vehicle Speed ◽  
Target Vehicle ◽  
Operation Rate ◽  
The Right

With the development of economy, there are an increasing number of cars as well as traffic accidents, thus intensifying the need to take measures to reduce traffic accidents and protect the safety of life and property. Vehicle distance is one of the most important indexes of traffic safety. The measurement of safety vehicle distance has become an increasingly hot research area of intelligent transportation. Through analyzing the basic principle of stereo vision and calibrating the parameters of the CCD sensors both inside and outside, this paper comes up with a method to measure the former vehicle distance based on stereo vision and DSP. Once the vehicle speed and distance form a non-security association, it will give a warning, and upload data or force speed-limiting. According to the different coordinates of the obtained images of the target vehicle from the left and the right sensor, this method can identify feature points, calculate distance to the target vehicle, and analyze the security of vehicle distance. The experimental results show that this method has wide measurement range, high measurement accuracy, and fast operation rate, thus it can meet the actual needs of the measurement of safe vehicle distance in intelligent transportation.

LATERAL MOVEMENT OF VEHICLES UNDER WEAK-LANE DISCIPLINE HETEROGENEOUS TRAFFIC

2016 ◽  
Vol 78 (4) ◽  
Author(s):  
Geetimukta Mahapatra ◽  
Akhilesh Kumar Maurya ◽  
Anil Minhans
Keyword(s):  
Vehicle Dynamics ◽  
Important Variable ◽  
Heterogeneous Traffic ◽  
Lateral Acceleration ◽  
Initial Increase ◽  
Lateral Movement ◽  
Traffic Condition ◽  
Safe Driving ◽  
Different Types ◽  
Road Geometry

Safe driving can be achieved by prevention of risky situations which requires the knowledge of the vehicle dynamics and road geometry. The Indian traffic condition is heterogeneous in nature and has weak lane discipline. Hence, vehicles interactions takes place laterally also along with their longitudinal interaction. Vehicles lateral movements (interactions) are quite high due to absence of lane discipline. Therefore, the lateral acceleration of vehicles are an important variable which characterizes the corresponding vehicle dynamics. Several studies have been done by various authors on lateral acceleration in curves, however, lateral movement study of vehicles on straight road section is also important to analyze vehicles’ maneuver in such traffic (i.e. traffic stream with weak lane discipline). Therefore, the present study is about the observation of lateral movements of vehicles over different types of roads in three metropolitan cities of India (Kolkata, Mumbai and Pune) under moderate traffic conditions. Lateral acceleration variation of five different types of vehicles (SUV cars, Sedan cars, Hutch Back cars, motorized three wheeler and two wheeler) have been recorded to investigate its relationship with vehicles longitudinal characteristics (i.e. longitudinal speed) in Indian heterogeneous and weak lane disciplined traffic. Lateral acceleration values quickly rises with initial increase in speed afterward lateral acceleration values reduces with further increase in vehicles longitudinal speed.  Impact of vehicle type and locations on the lateral maneuvering of vehicles have also been studied

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