An electronic and transportable nose for environmental gases monitoring based on mixed-signal SoC and open hardware

Today, the environmental monitoring and quality have a growing interest. This promotes the development of new monitoring tools, and especially those with outstanding reliability and response time, and nonstationary features. This paper presents the design and implementation of a transportable gas detection and environmental monitoring device. Ideas taken from the Arduino and Lego constructions are kept in mind during the design of the device, looking further facilitate the development of product family of this device; likewise, the use of reconfigurable and interconnectable platforms with open hardware are considered. The transducers have been selected based on their reliability, small size and easy inclusion in an electronic system. Then, was developed a device that supports transducers for environmental gases, such as: carbon monoxide (CO), ozone (O₃), volatile organic compounds (VOC), nitrogen dioxide (NO₂) and sulfur dioxide (SO₂); as well as the possibility to interface with other systems for common gases such as carbon dioxide (CO₂) and oxygen (O₂) before developed. Other environmental measures such as speed and wind direction, temperature and relative humidity, may also be included. In this case, a configurable platform based on mixed-signal circuits, PSoC5, was used for the development of embedded system. This platform can be interfaced with different Arduino shields and achieves the integration of several analog functions. This system manages, acquires and processes signals from the above transducers. The measurements can be displayed on an LCD display, save into an SD memory and send to the Web using Ethernet interface. The device is hand size, easy to carry and can operate with a battery. Its user interface is simple and provides updated and in-situ readings. Currently, successful results have been obtained from the functional and metrology testing of the manufactured prototype.