Real-time PID controller for UAV stability

Abstract

Recently there has been a significant rise in the popularity of multi-rotor UAVsdue to its ability to hover and ability to execute vertical take-off and landing. Advancesin the field of compact and powerful microcontrollers, efficient brushlessmotors, MEMS sensors has allowed us to build small autonomous quadcopterswith on-board controller for stabilization and control of it.This thesis is dedicated to implementation and testing of a 6-Degrees of Freedom(DOF) feedback control system for an Unmanned Aerial Vehicle (UAV) equippedwith inertial sensors with focus on Vertical Take-off and Landing (VTOL). Thebasic six maneuvers are move up-down, left-right and forth and back. The quadcopteris inherently unstable and under-actuated system because we have fourmotors to control 6-DOF of UAV. The quadcopter has independently actuated motorswhose rotation speed is controlled by flight controller. The flight controllerboard has a feedback PID (Proportional-Integral-Derivative) algorithm code burnedonto it. The PID controller has a initial set point and the readings from the gyroscopeand accelerometer are continuously fed back to the PID. The readings thatindicate the inclination along any arm of quadcopter will generate an error aftercomparing with the initial point and then PID will generate a correspondingoutput to eliminate the error and balance the quadcopter.