Pedestrians street crossing

Pedestrian street crossing behavior and crossing speed... 

Figure 3.3 gives the principle and the main elements of the stochastic simulation. The first step is the generation of the scenario, including the street and traffic. The next part is the generation of the pedestrian with his attributes. The driver and the vehicle with their attributes are generated in parallel. The vehicle includes the model for the measure of active safety under investigation. The simulation is time-based and evaluates each model and their interactions for each time step. In the end, either a collision happens or the pedestrian safely crosses the street. 

Projekt AMULETT. (2010). Retrieved August 15,2010, from http //www.projekt-amulett.de Meinecke, M., Roehder, M., Nguyen, T., Obojski, M., Heuer, M., Giesler, B., Michaelis, B. (2009). Motion model estimation for pedestrians in street-crossing scentirios. In 7th Inter-nalional Workshop on Intelligent Transportation. 

From the perspective of the design engineer, the most important aspect of pedestrian behavior is the street crossing speed. As people age their walking speed decreases and they need more time to cross the road. Unlike car drivers, whose speed is directly related to the likelihood and severity of a crash, in the case of pedestrians, their slow speed only increases their exposure to injury. It is therefore important to know at what speeds people cross streets, and what variables affect these speeds. 

Table 15-L Average and 15 percentile street crossing speeds (in meters/second) for younger and older pedestrians in various situations (from Knoblauch et aL, 1996).

Ten to 14 years old pedestrians also tend to dart out, but in their case the reason is that they do not yet have good street crossing habits, the traffic system is not yet fully internalized, and so they do not always apply safe pedestrian skills that they have already acquired but not yet turned into habits (Cross and Hall, 2005 Schieber and Vegega, 2002). According to an analysis by Sentinella and Keigan (2005) in the U.K. most of child pedestrian collisions... 

Figure 16.1. Critical pedestrian scenarios crossing the street remotely from a junction...

To summarize, the time needed to cross the border, that is, the border transfer velocity, depends on both the individual mobility on foot (diffusivity) and the quality of the roads (viscosity). Or stated differently the distance from the border where the passengers leave the taxi since the speed of the cars (water movement) drops below the speed of the individual pedestrian (molecular transport), depends on the relative size of pedestrian mobility and car mobility. Transfer velocities are large for fast runners and permeable road systems and small for physically handicapped passengers and narrow streets. 

All relevant processes are modeled and linked with realistic probability distributions. Each parameter is drawn randomly with respect to its probability distribution and possible dependencies on other factors in the simulation. The implemented scenario is an urban crossing scenario, as this is the most important one (see Sect. 3.2). The pedestrian crosses the street (straight road) from the right to the left from the view of the driver in the middle of a block. From the pedestrian s point of view, the traffic comes from the left. Scenario parameters include, for example, the geometry of the sidewalk, speed limit of the street or visibility restrictions. The traffic on the road itself is implemented as an exposure model depending on time of day and day... 

Fig. 3.4 Pedestrian tasks while crossing the street in the simulation (simplified)...

The second normal situation is a common crossing scenario where a pedestrian crosses the street from the right (see Fig. 4.2). A key parameter characterizing the mitigation of a potential conflict is thetime-to-collision (TTC), which is defined here as the distance to the projected collision point divided by the current vehicle speed. The TTC when the pedestrian enters the street in this situation is varied during the experiment ... 

Situation 4 (Fig. 4.5) False system response due to a pedestrian on the opposite side of an intersection while negotiating a right curve The driver follows the street in a right curve while crossing an intersection. 

Pedestrian restraint systems (pedestrian guardrail) are regularly used to prevent pedestrians crossing roads at unsafe locations. There is a tendency to remove such systems from certain roads as part of a general reduction in street clutter. 

I street lighting unchanged after new junction introduced I lack of pedestrian crossing facilities on approaches ... 

E Fail to notice pedestrians crossing when turning onto a side street. 

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