MNDOT

Objective:

The goal of this project was to provide the Minnesota Department of Transportation with design measures to improve pedestrian safety at free-flow leg intersections.

Survey

A survey was deployed to agencies and traffic engineers worldwide to gather data on ineffcient designs of free-flow leg intersections. The survey was was web-based and used php scripting to collect results and save them to the server.

intersections

Six intersections were also chosen for the study. Intersection selection was based on the following criteria:

Free-flow leg intersection.
Pedestrian sidewalks at all other corners of intersection.
High interaction between pedestrians and traffic.
MNDOT suggestions.

Video cameras were then set up at each of the six intersections to record pedestrian and traffic interactions. Traffic-controlling cameras were not available at the time, so the project used wireless video cameras that were able to transmit video over FM waves. A four-channel video recorder could recieve these waves and be accessed by a computer.

Analysis

After the video data was gathered from all the intersections, it was analyzed, and three different types of events were defined.

Event	Definition	Cases
Non-Event	No interaction between vehicle and pedestrian.	Pedestrian crosses when no vehicles are present.
Interaction	There is potential for a conflict between a vehicle and pedestrian.	Case 1: Vehicle slows, but pedestrian crosses street after vehicle. Case 2: Pedestrian attempts to cross but returns to the curb before crossing successfully. Case 3: Vehicle stops and allows the pedestrian to cross.
Incident	There was a conflict between vehicle and pedestrian.	Vehicles are forced to make abrupt changes to avoid contact with the pedestrian.

Based on these categories, the videos were analyzed and data was generated. From the data, an intersection was chosen in which to implement changes. Suggested changes were as follows:

Overhead crosswalk signs
Pedestrian crossing signs
Raised crosswalks
Rumble strips
In-ground and in-sign LED crosswalk systems

References

Aktan, F., Lee, Y., Neyens, D., Schnell, T., "How to More Safely Accommodate Pedestrians Through an Intersection with Free Flow Legs", Final Report for Minnesota Depertment of Transportation. Transportation Building, 395 John Ireland Boulevard, Saint Paul, MN 55155. March 2004.

Sponsors and partners

DOT

projects:

MNDOT