Measurement and Control System of Soil Moisture of Large Greenhouse Group Based on Double CAN Bus

According to the need of irrigation control of modern agriculture facility, a measurement and control system of soil moisture of large greenhouse group based on double CAN bus is designed. The system consists of host, outside CAN bus, slave unit, inside CAN bus, and sub-slave unit. The system adopts a master-slave way of working, in which, PC host accomplished centralized monitoring of all greenhouses, the slave unit accomplished cycle display, parameters setting of soil moisture of all blocks of one greenhouse, and the sub-slave unit is responsible for the soil moisture measurement and irrigation control of one block. The master and slave, slave and sub-slave, are linked respectively by outside CAN bus and inside CAN bus. By using the system combined with the agricultural expert system, not only centralized control and management, but also measurement and control in partition according to need can be achieved, so the crops get a timely, on-demand precise irrigation, it can not only improve the utilization ratio of equipment and water, but also favour the high yield and quality.