TU Graz scientists and CARES project partners are working on a new class of sensors to reduce the amount of air pollution caused by vehicle emissions.
According to the Horizon 2020 CARES (City Air Remote Emission Sensing) project consortium, the new sensors can be attached to roadsides, crash barriers or traffic signs to detect exhaust emissions of passing vehicles within a matter of seconds.
“We want to monitor vehicle emissions in cities and environmental zones under real conditions, without having to interfere with free-flowing traffic,” explains TU Graz professor Alexander Bergmann.
Bergmann and his team will focus on particle measurement, a field that the institute is well-versed in.
“The aim is to detect the exhaust class of each individual vehicle using these measurements,” notes Bergmann.
This could prove useful in helping cities introduce an emissions-based city toll: the higher the emissions of the car, the higher the charge would be.
Entry permits into environmental zones could also be monitored automatically, in which automatic barriers only open if the pollutant emissions of the approaching car are within the standard range.
The sensor technology could further be used to identify and pull out of traffic those vehicles in which engine performance and pollutant emissions have been manipulated with the help of particle filters and chip tuning.
Bergmann and his team made use of conventional tuning forks to test the prototype sensors and the results have been promising so far.
According to the scientists, the particles between the fork are excited through laser pulses, which in turn produce an acoustic signal and begin to ‘sing’ in the truest sense of the word.
Each individual particle emits acoustic signals which are recorded and then played back by the tuning fork. The more particles there are, the louder the sound becomes.
The volume can then be used to determine how many particles are in the environment.
The technology has already been used successfully for gas measurements, notes Bergmann.
Image and content: Mike Blake-Reuters via PRI/TU Graz