Abstract:A new door controlling system is designed to solve the problem of the traditional door about failing to realize the user's remote control and real time monitoring.The system uses the STC12C5A60S2 MCU as the main control unit, and via a short message remote control to open the door. The system adopts the method of mjpeg-streamer under Openwrt, an open source environment of Linux, to realize the function of remote real-time video viewing, and gates controlling through the sim900A short message module. The camera with human infrared sensor and photoelectric sensor can realize the dynamic monitoring of the environment outside the door of the household. Through the short message module, a warning message can be sent when the system detects an anomaly, meanwhile the front door status is stored in the cloud disk as an image. After testing, the system realized real-time video transmission, remote remote door opening and anti-theft alarm function; and the average single operation time was 11.42S.The system responds quickly, performs well, and has practical application value.