Simulation research of traffic behavior of road intersection pedestrian
CHEN Xue-mei(陈雪梅)1, WEI Zhong-hua(魏中华)2, GAO Li(高利)1
(1. School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China;
2. Traffic Engineering Key Lab of Beijing, Beijing University of Technology, Beijing 100022, China)
Abstract: Regarding the guarantee traffic safety, the traffic behavior simulation research of road intersection pedestrian has the important meaning. After the investigation and the process of data, community’s movement characteristic of the road intersection pedestrian were summarized, the vehicle speed change tendency of the mobile stream under the pedestrian influence were forecasted, and the simulation to the typical road intersection pedestrian behavior were carried out by using the microscopic simulation software and the governed speed parameter. Finally the road intersection improvement measure was proposed. The findings have the important meaning regarding improving the safety of road intersection.
Key words: pedestrian model; transportation simulation; microscopic
CLC number: TP491.2 Document code: A Article ID: 1672-7207(2011)S1-1037-05
1 Introduction
The pedestrian is an important participant, if the influence of pedestrian’s the transportation system is neglected, the effect of simulation may have the big difference with the actual situation. The confidence level of the road service performance appraisal and the transportation strategy formulation which using the transportation simulation would reduce greatly. Therefore, joining the influence of the pedestrian into the transportation simulation system is very necessary[1-2].
Although the history of pedestrian model's research is long, pedestrian model is applied in the software of transportation simulation in recent years. At present, the SMARTEST project group have studied the quite typical 57 kind of microscopic simulation software, only 8 kinds have contained the pedestrian model[3]. The survey result of SMARTEST indicates that interaction between the vehicles and pedestrian is a important object for traffic safety analysis, approximately 78% of the surveyor thought that the pedestrian should be taken an important factor in the simulation software[4]. Joining affects of the pedestrian into the microscopic transportation simulation software would cause the simulation results to be more credible and reasonable, therefore strengthening this aspect has the important meaning to the research.
2 Traffic survey and statistical analysis of road intersection
2.1 Selection of road intersection place
The selected place of road intersection should have
the representation. The road intersection between north avenue of Zhongguan Village and the northern four link west roads, symbolized that it has clearer graticule and high-rise construction which can be used for erecting camera’s all around. The traffic flow is big, and the road intersection does not have the overpass and the underground walks nearby. The distance between the north and south imports is long, the following time of pedestrian and the vehicle also is long. Synthesizes the above factor, this road intersection was chosen to investigate information.
Before taking the photograph of road intersection, the investigators surveyed the road intersection geometry size on the spot firstly. In order to carry on the analysis to the photograph material, the surveyer made the suitable mark in each road intersection. The basic situation of investigation is as follows.
Weather conditions: The weather is clear, south wind 2—3 levels, highest temperature approximately 5 ℃.
Acquisition time: on April 4, 2010 in the morning 7:30—9:00 and on April 4, 2010 in the afternoon 5:30—7:30.
Place: the road intersection between the north avenue of Zhongguan Village and north four link west road.
Gathering method: Two digital cameras are separated in two high-rise buildings which situates in northwest and southeast, the camera photographs are in the road intersection situation responsibly.
2.2 State of road intersection
The north and south overlapping distance of road intersection is approximately 80 m, the east and the west are away from short. In the road intersection, counterclockwise treats transfers area are equipped, but the imports between the east and the west is long, and counterclockwise treats which transfers the area between the south and the north imports is short. On the imports between the south and the north, the mobile traffic lane and the mobile traffic lane, the mobile traffic lane and non-motor vehicle have the physical isolation. The import between the east and the west were separated by four link roads, the mobile traffic lane and the mobile traffic lane, the mobile traffic lane and non-motor vehicle do not established. The width of pedestrian crossing is 5 m, and two streets are needed between the north and the south to the pedestrian. Basic situation of import and export are shown in Tables 1-2.
2.3 Mechanical transport condition analysis of road intersection
There are many traffic lane divisions of imports between the south and the north, the north import is also equipped with the physical isolation facility, the motor vehicles of different beginnings are isolated. The import between the east and the west is parallel with four links road, the road surface is wide, direct current is big. Each import mobile traffic flow magnitude statistics is shown in Table 3.
Table 1 Basic situation of import
Table 2 Basic situation of export
Table 3 Road intersection vehicle flow
Table 4 Matching time of road intersection signals
2.4 Timing characteristic of road intersection signal
The north and the east of the road intersection is only equipped with the direct and the turn left, the vehicle which turn right is not controlled by signal. The north and the south left, the direct and the right-turn have the respective special-purpose phase. Matching time of road intersection signals is shown in Table 4.
3 Analysis of data
The speed of the vehicles at the crossing are put into two categories which is decided by whether there is pedestrian or not: Speed without pedestrian factor, speed within pedestrian factor, and vehicles of different directions were analyzed as well. Vehicles are divided into big size and small size, and middle size is removed as its number is really small.
3.1 Selection of sample size
Considering average speed, the minimum volume of the sample data will match the confidence level of constant t, standard deviation of the spot speed σ, permissible error of the speed measurement, and the formula is:
In this investigation, rural road section is selected and the confidence level is fixed at 95%, that is t=1%, E=2 km/h. It is pointed out in the Manual of Traffic Engineering Studies that when the average standard deviation ranges from 6.8 to 8.5 km/h and the fluctuation is not apparent, σ=8.0 km/h is recommended, which means that the minimum volume should be 62. The average volume of the road section meets the requirements.
3.2 Vehicle speed without pedestrian factor
Data that the pedestrian interference is 0 in the sample was analyzed. The average speed of four entrance’s vehicles (east, south, west and north) that passed the crossing was obtained. The speeds of different entrances are shown in Table 5.
Table 5 Speed of different entrances km/h
3.3 Vehicle speed with pedestrian factor
It is easy to find from Fig.1 that the speed distribution of straight vehicles has great fluctuations with pedestrian factor, and straight vehicles whose speed is less than 2 m/s are found. It shows that straight vehicles has a low speed of passing the crossing and a long detour distance with the pedestrian factor. The other entrance has similar situations.
3.4 Comparative analysis
It is easy to find from Fig.2 that the peak vehicle speed percentage with pedestrian is earlier than the situation without pedestrian and has obvious fluctuations, it show that pedestrian has great disturbance to straight vehicles of the north entrance. The other entrance has similar situations.
Fig.1 Speed analysis of north entrance straight vehicles
Fig.2 Comparison of straight vehicles speed and pedestrian speed of north entrance
4 Pedestrian traffic behavior simulation of crossing
4.1 Process of simulation
Cube Dynasim is a powerful transportation planning software, it can help transportation planners to test various traffic characteristics and to predict future travel rules, the micro-simulation platform of Cube Dynasim is easy to use and it can simulate transportation network of any scale[5]. Cube Dynasim was used to simulate the crossing of Zhongguancun district in this paper, and its logic flow is shown in Fig.3. Picture of simulation is shown in Fig.4
4.2 Results of pedestrian traffic intersection simulation
Fig.5 shows the screenshot of the actual video data and Fig.4 shows the corresponding simulation picture. Straight north-south vehicles are disturbed by pedestrian, and the corresponding simulation of vehicles has obvious detouring behaviors.
Fig.3 Flow chart of simulation
Fig.4 Picture of simulation
Fig.5 Photo of crossing
5 Conclusions
(1) Consummate symbolizes and graticule. For instance, the maintenance routine, the inspection and the renewal would be carried onto the symbol, and the adjustment pedestrian crossing line and the parking sets, repairs the symbol and the graticule should be corrected.
(2) To improve the quality of traffic control. Including positions and the possible arrangement timing and reasonable establishment signal, the road intersection controlling, the establishment regulating which symbolizes that installment “electronic police”, the low wooden tree-planting belt nearby, the pedestrian crossing sidewalk, and to prevent the pedestrian to pass through the four corners and strengthen the road intersection manual controlling.
(3) Increase the safety equipments. Establishes the safety equipment in the road intersection, can not only play the role of preventing traffic accident, but also the role for the transportation unimpeded positive displaying.
(4) Improve the transportation participant quality. To improve the pilot quality through the regular training inspection, the propaganda, and educational activities, to strengthen the consciousness of participants, specially to strengthen the young people’s legal quality.
References
[1] JING Chun-guang, WANG Dian-hai. The mixed traffic conflict analysis and processing method of typical road intersection[J]. China Civil Engineering Journal, 2004, 6(6): 97-100. (in Chinese)
[2] LI Zhi-peng. The vehicle microscopic behavior research of the signal road intersection under mixed traffic flows[D]. Beijing: Beijing Jiaotong University. School of Traffic and Transportation, 2004: 30-31. (in Chinese)
[3] ZHAO Jian-li. The pedestrian traffic research of the signal road intersection under the mixed traffic flow[D]. Beijing: Beijing Jiaotong University. School of Traffic and Transportation, 2004: 23-24. (in Chinese)
[4] SUN Zhi-yong. The pedestrian traffic characteristic research of Signal of road intersection pedestrian road intersection[D]. Beijing: Beijing University of Technology. College of Architecture and Civil Engineering, 2004: 67-69. (in Chinese)
[5] WEI Ming, CHEN Li, CHI Rui-juan, et al. Survey and analysis of traffic at typical intersection of congested road in Beijing[J]. Journal of China Agricultural University, 2004, 9(1): 91-95. (in Chinese)
[6] WU Jian-ping, HUANG Ling, ZHAO Jian-li. The behavior of cyclists and pedestrians at signalized intersection in Beijing[J]. Transportation Systems Engineering and Information, 2004(5). (in Chinese)
(Edited by CHEN Can-hua)
Received date: 2011-04-15; Accepted date: 2011-06-15
Foundation item: Project (QC200805) supported by Jiangsu Automobile Key Laboratory; Project (2009BAG13A04) supported by the National Science and Technology Support Programs; Project (90920304) supported by the National Natural Science Foundation of China
Corresponding author: CHEN Xue-mei(1978-), Pingyi, Shandong Province, Doctor, Lecturer; Tel: +86-13520381142; E-mail: chenxue781@126.com
