Sensor technology in roadway infrastructure
How devices are strengthening the lines of communication between human and automated drivers
For many departments of transportation (DOTs), the collection and sending of real-time traffic data to roadway users is high priority. One way agencies nationwide are achieving this goal is through the use of sensor technology in roadway infrastructure, such as pavement markings or signs, allowing them to strengthen Vehicle-to-Infrastructure (V2I) communication.
According to a 2018 study by the National Center for Biotechnology Information (NCBI), sensors in both vehicles and roadway infrastructure are capable of providing information on traffic, roadway, and vehicle conditions, better preparing motorists and non-motorists for what to expect as they travel.
“Preparing roadway users for what lies ahead is key when it comes to increasing safety,” said ATSSA Senior Technical Advisor Eric Perry. “As an industry, we have come a long way with the technical options that are available to us to advance roadway safety—sensors being one of them. By using a number of sensors, we can better and more accurately detect things like traffic volume, detours, or road closures caused by crashes that can make a substantial positive impact.”
One recent roadway project including the use of infrastructure sensor technology was conducted in Colorado. The state’s DOT partnered with the technology start-up Integrated Roadways last year to install its “Smart Pavement” product on a stretch of roadway slightly south of Denver. The product uses sensors that can detect the direction, speed, and weight of a vehicle.
“Smart Pavement is … transforming roads into a digital platform for advanced mobility applications,” said Integrated Roadways CEO and Chief Technology Officer Tim Sylvester. “Smart Pavement identifies vehicle positions and behaviors in real-time, simplifying autonomous vehicle operation, providing dynamic traffic information, automatic notification for accidents, permanent vehicle counts, pavement condition indexing, and data-driven safety improvements. Future versions may make the road financially self-sustaining by selling access to data, connectivity, and services.”
In 2017, the Arizona Department of Transportation (ADOT) installed sensors in roadway pavement along stretches of Interstate 17 to monitor traffic flow and roadway conditions, allowing the department to make impactful decisions for future projects.
Other concurrent research efforts are also being conducted. Senior research engineer Jerry Ullman and associate research engineer Adam Pike with the Texas A&M Transportation Institute (TTI) said the institute has been involved with different projects that adapted roadway infrastructure to better support Connected Automated Vehicles (CAVs).
Pike said he worked on a sign project in conjunction with 3M, using the company’s technology that is similar to a QR code, but equipped with more options. Researchers embedded the codes in signs, which allowed CAVs to use their infrared camera systems to read the codes.
“The infrared camera systems cast out their own light and then evaluate within the infrared spectrum to determine what the signs look like,” Pike said. “If the sign has one of these codes on it, it will be able to relay a specific message. Those codes can be changed if they're connected to the cloud so the owner or operator could change the message on the sign if there was an incident ahead of the driver.”
Ullman said roadway infrastructure was initially designed for the human driver and with new CAVs, the human driver will eventually be taken out of the equation, so the question is what do these CAVs need that differ from what a human driver?
“The idea of utilizing sensor technologies in roadway infrastructure is including intelligent assets to support CAVs and human drivers as well,” Ullman said. “Having data or information from everything, not just traffic anymore, is going to go a long way to helping agencies and even private sector entities better manage their resources. Having sensors in infrastructure and our equipment allows drivers to know what lies ahead. It's a powerful tool.”