First results of iButton® loggers and infrared camera application inside a greenhouse

Greenhouse microclimate management (temperature, relative humidity) plays a very important role in order to optimize the production process improving pest and disease control, irrigation and energy efficiency. The systems mostly used in Sicily (south Italy) to record the ambient parameters are made up of fixed measuring stations able to give useful information about the climate inside the greenhouse limited to some pre-fixed points. In this study we texted a novel system made up of humidity and temperature data loggers (iButton®) placed inside a greenhouse. The iButton® temperature/humidity logger (DS1923) is a rugged, self-sufficient system that measures temperature and/or humidity and records the result in a protected memory section. The DS1923 is configured and communicates with a host-computing device through the serial 1-Wire® protocol, which requires only a single data lead and a ground return. A total of 8192 8-bit readings or 4096 16-bit readings taken at equidistant intervals ranging from 1 s to 273 hours can be stored. The data loggers reduced dimensions (16.3 mm diameter and 5.9 mm tall) allow to not disturb vegetation in positioning them. In this study, twenty iButton® loggers were uniformly distributed inside the greenhouse also near to the vegetation and gave the opportunity of accurately control the ambient parameters with great flexibility due to the facility in positioning and moving them. Furthermore, the infrared camera FLIR P640 was used to obtain accurate temperature measurements in correspondence with the vegetation. The iButton® data were also overlapped to those obtained by the infrared camera. They together allowed to identify the critical points of the ambient parameters as useful tool for the management of the farming operations inside the greenhouse.