The present invention relates to a curtain control system and a curtain control method. When a controller receives a curtain-releasing signal, a braking module releases a curtain so as to lower it, a current position detecting module detects an absolute position of the curtain, and the controller calculates a current velocity and a current acceleration of the curtain according to a variation per unit time of the absolute position. When the current velocity is equal to zero or the current acceleration is smaller than zero, the controller controls a motor to lift the curtain or controls the braking module to hold the curtain at a current position. Accordingly, the present invention uses the absolute position to calculate the current velocity and the current acceleration of the curtain so as to determine whether the curtain has encountered an obstacle.

A telescopic curtain guide rail includes an inner rail, an outer rail and a transmission unit. The inner rail is embedded in the outer rail, the transmission unit includes a driving wheel connected with a motor, a driven wheel, two fixed pulleys and a conveyor belt. The driving wheel and the driven wheel are located at two ends of the curtain guide rail, the two fixed pulleys are respectively located at other ends of the inner rail and outer rail. The driving wheel and one fixed pulley are located at two ends of the inner rail or outer rail, the conveyor belt is wound on the driving wheel, the driven wheel and the two fixed pulleys. A telescopic operation of the curtain guide rail can change positions of the two fixed pulleys simultaneously, and the curtain guide rail is simple to use and has a small occupied area.

The present application provides a driving device including: a driven wheel configured to connect a pulling rope; a driving mechanism configured to drive the driven wheel to rotate; wherein the driving mechanism includes a driving motor, an output shaft, and a transmission assembly, the transmission assembly is connected between the driving motor and the output shaft, and the output shaft is connected to the driven wheel; when the output shaft is in a first state, the output shaft is coupled to the driven wheel and the transmission assembly respectively to form transmission connection; when the output shaft is in the second state, the output shaft is decoupled from the driven wheel and/or the transmission assembly to disconnect the transmission connection. The present application further provides an electric curtain having the driving device.