An autonomous line following robot for delivery within an industrial setting

Abstract

A line-following robot is an autonomous mobile robot that can follow a predefined path. Such robots are typically used within industrial settings or hospitals because of their shorter transit times over longer distances. This project shall investigate various techniques used in line-following robots. Although the robot still follows a dark path over a light surface which is the traditional concept of line-following in autonomous land vehicles, a colour sensor is used to detect different coloured “entry points” that define different routes that the robot can take, each leading to a different destination. The robot shall also sense the presence of obstacles along its path and navigate around them. An autonomous vehicle controlled by an Arduino microcontroller is built and various sensors are attached to this robot. The Proportional-Integral-Derivative (PID) and Fuzzy Logic controllers will be developed for line-following and evaluated by their performance and efficiency. The “Follow the Gap” Method (FGM) will also be implemented for the obstacle avoidance properties of the robot. In a realistic scenario i.e., industrial setting or hospital for examples, a track is layed out using mainly black tape and different coloured tape. The black tape will be used by the robot as a guide to where it should be going, similar to a road. The coloured tape will be used to navigate towards the correct route. The autonomous vehicle’s program takes a single input, which will be the colour to follow. The robot will follow the black tape using the PID algorithm or Fuzzy Logic, until it finds a “STOP”, which can be defined by a specific-coloured tape of choice. When the robot encounters a stop, it will check the different “entry points” that are near that stop, defined by different coloured tape. If any of these colours match the input color, the robot will keep moving forward to the direction of the correct colour, otherwise it will backtrack. Obstacle avoidance is also implemented by using the robot’s ultrasonic sensor, which makes the robot avoid the obstacle and get back on the line.