A compact autonomous inspection system for greenhouse environmental information sensing and three-dimensional visualization

Facility environmental conditions directly affect the growth and quality of crops. The conventional method of laying multiple sensor nodes is costly and difficult to communicate, while the expensive ground robot monitoring has shortcomings such as universality and interference with agricultural activities. A compact autonomous inspection system for greenhouse environmental information sensing and three-dimensional (3D) visualization was developed, composing of a sensing module, a driver module, and a control and communication interface, to monitor the carbon dioxide concentration, relative humidity, temperature and illumination intensity information at different spatial positions of greenhouse autonomously and automatically. Sensing module connected and controlled by the driver module autonomously moved and acquired environmental information. Meanwhile the control and communication interface, based on Qt and Open Graphics Library (OpenGL) technologies, performed functions of remote controlling, data receiving and visual display. ZigBee, 4G wireless components and Ali Cloud platform cooperated to realize the hierarchical command communication and data transmission among the system. Based on Ultra Wideband (UWB) positioning technology, combined with the trilateral positioning algorithm, the fusion of sensing data and positioning data was realized the 3D visualization, further improving the display dimension of facility environmental information. The practical measurement showed that the sensing module, driven by the driver module, can monitor the facility environmental information at different spatial positions in real time. UWB positioning method realized the accurate positioning of the monitoring device, the average maximum errors of the distance information and height were 0.114 m and 0.012 m, which fully meets the positioning requirements of the facility environmental monitoring. The control and communication interface ran normally, operated friendly and displayed visually. This greenhouse 3D environmental sensing autonomous inspection system can effectively reflect the uneven environmental field of the facility agriculture with low cost and good compatibility, providing effective technical support for the accurate control of the facility environment and the high quality growth of the facility crops, with huge potential for agriculture application.