Trying to determine an appropriate driving speed under less than ideal conditions is a challenge for the motorist. It is equally difficult for law enforcement agencies to enforce and cite someone going too fast for poor conditions. The determination is difficult and subjective. In many cases drivers are cited for going too fast for conditions after an accident has happened. Currently no system is available in the U.S. to identify safe speed limits on a variable basis.
This project developed a variable speed limit system that utilizes fuzzy control technology to identify speed limits appropriate for differing environmental conditions. Fuzzy technology is proving to be effective in a broad cross-section of difficult control problems. In particular, fuzzy control concepts are well-suited to the control of complex non-linear systems where classical mathematical analysis is difficult and imprecision is
inherent.
The project objectives were to develop a variable speed limit signing system for identifying speed limits that are more realistic and appropriate for environmental conditions than posted highway limits.
The goals were achieved through the following objectives:
- Developed a fuzzy control algorithm that uses environmental conditions to define
speed limits; - Built a test system for conveying variable speed limits;
- Tested and validate the system in a simulation environment; and
- Evaluated the potential for operational field testing of the system.
Project Duration: 1997 – 1998