This idea revolves all around sound, more accurately noise and our daily exposure to it. A low level of noise pollution is a major benefactor to a high quality of living. A good night’s sleep or the ability to focus on the current task depend on a quiet environment. Noise pollution can cause high stress levels, tinnitus, sleep disturbances and other harmful effects. Today’s cities are often very noisy and could be improved to reduce noise by clever design. The first step to solve a problem is to become familiar with it.
This is where my idea comes in: a network of small microphone sensors measuring and reporting sound levels. These can be placed anywhere, are weather resistant and self-sustaining. Positioning these throughout a city enables real-time data on noise levels, which can be used by governing bodies and companies to make educated decisions about protection from noise emitters like roads and construction sites.
Every single sensor of the network consists of these components:
• Microphone and Amplifier --> Converting sound into an analog voltage.
• Micro-controller --> Converting voltage level to decibel and controlling the sensor.
• Wireless module --> Communication with the network.
• Battery and power circuit --> Ensuring power to the sensor.
• Solar cell --> Converts sunlight into electrical power for continuous operation of sensor without large battery.
• Case --> Protects electronics from weather.
Prototypes build by me from these components did not exceed $20 and should be producible on a larger scale for about $10.
The setup is simple: Place the sensor securely ensuring that the solar panel is in direct sunlight. After power-up the sensor will connect to the network and start sending noise level messages.
Significant battery life is achieved using a solar panel, which recharges the battery of the sensor continuously. Using the built-in sleep mode of the microcontroller, units can save a significant amount of energy. Units consume at peak about 50mA (30mA to send data to network, and 20mA for the microcontroller). Running at peak for 5 seconds each 15 minutes, it consumes an average of 5,2 mA. With only a 2500mA battery, the sensors can operate for 20 continuous days without any input of energy.
The third picture shows a map overlaid with noise levels from sensors placed at the red dots.