Stable is quadcopter which I made more recently for METU Robot Competition. Its purpose is following line autonomously. I used Raspberry Pi Zero to process images which are come from Pi Camera. I used image processing and computer vision to find a line and decide which move the robot should do. Robot’s purpose is always being center of the line and perpendicular according to its camera, so it corrects its place with side moves and it’s an angle with turning. My robot makes forward and side moves step by step. For example, when it decides to go to forward, it goes forward with 15cm, but turning is different. When my algorithm detects curve, it calculates how much should robot turn in degree, so the robot doesn’t turn step by step. I became first in METU Robot Competition “Autonomous Unmanned Aerial Vehicle” category.