ATTITUDE STABILIZATION FOR CUBESAT USING PID AND LQR CONTROLLERS

Abstract

CubeSats often tumble uncontrollably after deployment due to uneven forces, requiring stabilization before accurate orientation control. This work explores two control strategies: a PID controller for initial detumbling and an LQR controller for precise attitude regulation. The system uses magnetorquers with a B-Dot algorithm to reduce spin, then employs reaction wheels for fine three-axis control. The spacecraft’s motion is modeled using Euler’s equations and Keplerian orbital dynamics, with magnetic field data provided by the IGRF model. Key hardware includes magnetorquers, reaction wheels, gyroscopes, and magnetometers. Simulation results compare PID and LQR performance, showing that PID is better suited for fast, simple detumbling, while LQR excels in maintaining stable and accurate orientation with better energy efficiency. Keywords: CubeSat, stabilization, PID, LQR, Control, magnetic torque.