A portable environmental monitoring system based on WSN for off-the-shelf sensors

Environmental monitoring is required almost in every walk of life, especially in manufactory, truck farm and hospital wards. But the collection of many different monitoring sensors for synthetical analysis is difficult because most existing sensor works alone and there are varies of sensor interfaces. This paper presents a novel environmental monitoring system based wireless sensor network with SD memory interface to improve off-the-shelf sensor products. We designed a main-node with SD memory interface to gather sub-node sensor data, then five small sub-node boards are designed to be installed in existing sensors, such as temperature/humidity sensor, infrared sensor, smoke detector and door magnetism detector. Via the general SD memory interface, a portable tablet can read environment information instantaneously, which could be recorded in magnanimous nand flash storage at the same time. The performance evaluation shows that our monitoring system is flexible and convenient to apply to off-the-shelf commercial sensors.