There are already devices that can detect vehicles that are overspeeding or emitting too much noise. Now, scientists are developing a sensor that can be used without human control to detect which vehicles are expelling excessive exhaust.
The sensor was developed by a team at the Technical University of Graz (TU Graz) in Austria as part of the European CARES (Urban Air Remote Emissions Sensing) project, which uses a dual tuning fork. These tuning forks are initially set to vibrate using laser pulses. When particles passing through the exhaust gas of the vehicle propagate through the air and then pass between the tuning forks, the particles are excited by vibration such that each of them produces an audible signal.
The greater the number of particles present, the greater the "sound" produced by the exhaust. If the sensor is combined with a camera that captures the vehicle license plate, the human user can identify which individual cars, trucks or motorcycles exceed the allowed emission levels.
The researchers hope that these sensors will be put into production by the end of 2022 and are currently planned to be installed alongside the roads of cities participating in the CARES project, such as Milan, Prague and Krakow.
“We want to monitor vehicle emissions in urban and environmental areas under real conditions without having to intervene in the flow of traffic,” said Alexander Bergmann, director of the TU Graz Institute of Electronic Sensor Systems. “Our goal is to use measurements to determine the emission level of each vehicle.”
The owner of the offending vehicle may be subsequently fined, detained, charged for continued vehicle usage, or prohibited from entering environmentally sensitive areas.