A Study of Complementary Filter Algorithm for Four - rotor Helicopters Attitude Control System

The focus of this study is on the attitude estimation of the four-rotor helicopter known as quadrotor. The choice of the algorithm is a complementary filter based on quaternions. For the four-rotor helicopter system has nonlinear, strong coupling, multi-variable features, it is difficult to obtain the accurate attitude values, and in order to solve this problem a quaternion-based complementary filter algorithm is applied. The Inertial Measurement Unit (IMU) is used to estimate four-rotor helicopters attitudes. The traditional PID controller is used to control the four-rotor helicopter attitude. This system is implemented on a newly designed compact STM32 board. The board contains the STM32F103RBT6 chip, the attitude sensor MPU-6050 and hmc5883l, the wireless communication module nRF24L01. The hovering experiment results presented in this paper provide good evidences that the quaternion-based complementary filter algorithm can obtain accurate attitude values, it reduces the amount of computation system, and provides an algorithm for four-rotor helicopters attitude solver. Copyright © 2014 IFSA Publishing, S. L.