UTSA engineers develop inexpensive ‘smart’ stop sign to improve rural road safety


Engineers from the University of Texas at San Antonio (UTSA) are building and testing a new low-cost, self-powered thermal system that will detect vehicles, improve the visibility of stop signs, and help prevent intersection deaths, particularly at rural locations.  

Rural roads account for 70% of the USA’s byways and the location for 54% of all fatalities, according to the US Department of Transportation’s (USDOT) Federal Highway Administration (FHWA). Without access to a power supply, they are more likely than other roads to lack signals and active traffic signage. The existing types of sign are often difficult to discern due to confusing backgrounds and foliage, with these problems exacerbated at night.

To improve driver safety, Sara Ahmed and Samer Dessouky, professors in the UTSA’s College of Engineering, created a low-cost, self-powered intersection detection and warning system to alert rural motorists about potential dangers. The next-generation stop sign uses a multi-pixel passive infrared (IR) sensor that detects a vehicle as it approaches an intersection. Once the vehicle is within the sensing range, a signal beacon triggers the stop sign’s flashing system.

“The IR sensor observes thermal signatures and processes them to detect passing vehicles,” explained Zachary Balcar, a master’s student in the UTSA’s Department of Electrical and Computer Engineering. “It distinguishes the vehicle’s direction of travel, estimates the velocity of its thermal signature, and determines the classification of the vehicle.”

Overall, the UTSA’s smart system has a 90% vehicle detection rate and a vehicle classification accuracy of 72%. Compared to current traffic sensing technologies in urban areas, such as electro-magnetic loop inductors, video image processors and microwave radar, the new system consumes less power and offers better accuracy. The new technology is also much less expensive to produce. Current safety systems can cost as much as US$5,000. UTSA’s detection promises to be a fraction of the price at US$60 to US$100 per unit.
The low-power rural intersection detection and warning system was developed with support from the Connect program, a collaborative research program that is co-funded by UTSA and the San Antonio-based Southwest Research Institute (SwRI). The project team has filed an invention disclosure for the system, which was recently recognized nationally by the American Road and Transportation Builders Association (ARTBA), and expects to adapt the technology to pedestrian detection, for border security and for vehicle-to-infrastructure (V2I) communications systems.

Prof. Ahmed added, “Our off-roadway system can be installed on urban or rural roads completely independent of the utility power grid, because it is powered by small solar panels and functions in all weather conditions.”

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Adam joined the company in 1994, and has been News Editor of TTT since 2009. In his other role as Circulation Manager, he helped create the original Traffic Technology International distribution list 23 years ago, and has been working on it ever since. Outside of work, he is a keen fisherman, runs a drumming band, and plays an ancient version of cricket.