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Noise pollution is a growing problem in large cities, affecting the quality of life of the population. To address this challenge, a French company is testing an innovative sound radar that identifies excessively loud vehicles and allows for automatic fines.
Sound pollution in traffic is a growing problem. To combat it, technology advances with increasingly precise solutions. The sound radar “Hydre” is an example of this. Developed by the French company Bruitparif, it combines acoustic sensors and cameras to identify vehicles that exceed the permitted noise limits.
How The Hydre Radar Works
The Hydre consists of two acoustic modules that work together. Each module has four microphones capable of measuring sound 25 times per second. These measurements allow for calculating the intensity of the noise and its origin.
To ensure accuracy, the sensors are protected by acoustically transparent metal cages, preventing damage and vandalism.
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The system also includes three cameras. One wide-angle camera captures the entire scene at the moment of a possible infraction.
Two other cameras automatically read the license plates of vehicles (ALPR), both at the front and the rear. This allows for precise identification of which vehicle generated the excessive noise.
All components are housed within a secure metal structure. Data processing and transmission are performed directly on the device. The information is encrypted to ensure security and integrity.
Identification and Registration of Offenses
The Hydre radar operates following a rigorous process. First, the sensors determine the dominant noise level every 40 milliseconds.
Next, they cross-reference this information to identify the sound source and calculate the distance of the vehicle. Thus, they adjust the recorded value to a standard reference of 7.6 meters, ensuring standardization in measurements.
If the corrected noise exceeds the established limit, and if environmental conditions are suitable, a file of a possible infraction is created. The system then analyzes videos and images before and after the considered critical moment. This helps to correctly identify the offending vehicle.
The next step is to compare the trajectory of the dominant sound with the trajectories of the vehicles in the scene. If there is any doubt about which vehicle generated the noise, the case is discarded. The system excludes situations where there are multiple vehicles heading towards the sound source, avoiding confusion.
If the infraction is confirmed, an image of the vehicle is extracted. In it, a box marks the identified car, and a circle indicates the source of the noise.
Then, the system consults the ALPR cameras to retrieve images of the license plate and perform automatic reading of the number. All these elements compose the infraction file, which is sent electronically to a monitoring center.
Initial Tests and Results
Between January and October 2022, the first phase of tests for the Hydre was conducted in France. The experiment involved the installation of prototypes in eight locations, distributed across seven communities.
The goal was to evaluate the technology’s performance in real conditions, but without issuing fines during this phase. The results were considered encouraging.
The device managed to detect noisy vehicles within a radius of 15 meters in each direction, even in areas with heavy traffic.
During the tests, the radar identified between 10 and 44 vehicles per day that exceeded the limit of 83 dB(A). This value was defined only for the experimental phase.
There is still no decision on what the final limit established by the Ministry will be, but it is estimated to be between 83 and 90 dB(A). The higher the limit, the fewer infractions will be recorded.
The Future of Noise Monitoring
The Hydre radar technology represents an advance in noise regulation in traffic. With precise measurements and automation, it can assist in controlling noise pollution and improving urban quality of life.
The next step will be to define the rules for applying fines, making this technology an effective tool in noise management in cities.
Ódio de descargas abertas uns poucos acabando com o sossego de uma população
Me sonho é colocar muitos aonde moro … e moto dia , noite , madrugada , até a chuva NÃO os mantém afastados…
Que maravilha! que venha logo pro Brasil. Odeio barulho!!
Até que enfim uma invenção que realmente não seja só pra nos roubar.