Automatic Light-Controlled Venetian Blind : Design and construction of a light-controlled Venetian blind

Sammanfattning: The demand for automated home solutions is growing and it has created a market for automated blinds. For now most of these solutions seem to focus on fully opening and closing, either rolling blinds or slat blinds, with different electronic solutions. There doesn’t seem to be many solutions for continuously regulating light inlet based on ambient light. This project examined the possibilities of continuously regulating the amount of natural light let through a window. This was tested by measuring ambient light on one side of the blind with light dependant resistors (LDR’s) and regulating a Venetian blind based on measured light intensity. A feed-forward controller was implemented, programmed on an Arduino Uno board, to control sensors and actuators that regulate the blind. A prototype unit was built on a window-resembling wooden frame to evaluate the performance of the controller. The light sensitivity of LDR’s were sufficient for measuring differences in ambient light in different conditions where an automated blind could be used. The final prototype could be set to adjust light inlet in increments for changes in ambient light, thereby opening up to uses beyond simply closing and opening a light inlet. Future improvements could be to implement a feedback controller (e.g. a PID controller). The controller could be set to a certain reference as preferred ambient lighting in a room, thereby letting the controller adjust the blinds towards that reference value while conditions outside and inside change during the day. This could also be implemented in already existing smart home solutions.