Nowadays, internet and mobile technologies are developing and being used in everyday life. Systems based on mobile technologies and IoT (Internet of Things) are being popular in every area of life and science. Innovative IoT applications are helping to increase the quality, quantity, sustainability and cost effectiveness of agricultural production.
In this study; a system which monitors temperature, relative humidity and PAR (Photosynthetically Active Radiation) and warns the farmer via SMS if any of these atmospherical parameters is beyond the pre-defined limits, in order to prevent damages to the plants, was developed. A software and hardware was developed which interprets data from sensors and transmits data into GSM terminal. Data have been collected with a computer that is connected to the system via USB. Later, these data have been used to identify data loss via GSM connection. A website has been used to monitor actual values and save data in an online database.
Experiments was held firstly in a laboratory for 6 months during development period and then in a greenhouse between 21 February and 25 February, 2015. Temperature, relative humidity and PAR values were uploaded to a remote server via GPRS and analyzed on the computer. Between these dates; temperature values outside the pre-defined limits occurred 3 times and relative humidity values outside the pre-defined limits occurred 10 times. The developed system sent 70 SMS messages which informs the farmer that temperature is low for 2100 minutes total and 129 SMS messages which informs that the relative humidity is high for 3908 minutes total. Total SMS loss was identified as 0.5%.
At the end of the experiments, differences was observed between data saved on the computer and data on the remote server. These differences were 150 repeating records, 25 missing record and 1 wrong record on the remote server. It is believed that these errors occurs because of the EMI (Electromagnetic Interference) from GSM terminal and atmospheric charges.
In conclusion, greenhouse monitoring systems such as developed in this study are seem to be successful. When designing systems to be used in greenhouses, a faraday cage which blocks the EMI and an earth connection should be used to protect the system from atmospheric charges.
