Design of a Low Cost Four-Channel LDR Based Line-Follower Sensor with Transient and External Interference Compensations

A line follower robot is a mobile robot that detects and follows a line drawn on the floor. A vast number of works proposed different sensing solutions for recognizing and following a line path, such as phototransistors, cameras, and infrared sensors. However, only solutions with low computational burden are adequate in case of limited processing, and low-cost requirement. The main contributions of this research are the implementation of a four-channel LDR based on a line-follower sensor and a novel methodology for recognizing colors at high speed with these LDRs. This proposed low-cost equipment enables the robot to recognize lines of different colors and external illumination. The main advantage of the proposed solution is the simplicity and low computational burden that enables its use in a low-cost microcontroller and for educational purposes. The results have shown the applicability of the proposed solution for identifying and tracking a line path.