Control of a Quadrotor Equipped with Robotic Arm Based on Disturbance Estimation

In recent years, unmanned aerial vehicles (UAVs) have become popular in many countries in the industrial and scientific research fields because of their high speed and maneuverability. This research investigates a compound system consisting of a quadrotor and a series robotic manipulator. Joining of these two systems aims at utilizing the agility and flexibility of multi-rotor UAVs and dexterity of robotic arms. This configuration makes UAVs able to perform more complicated tasks. First, kinematics and dynamics of quadrotor are presented using quaternion and Newton-Euler equations. Next, a 3-DOF robotic arm connected to the bottom of the quadrotor is considered and its kinematics and dynamics is derived using Newton-Euler recursive algorithm. In order to control the quadrotor, two inner-outer loops are used for its orientation and position, respectively. The torque resulted from arm operation or exerted force to its end-effector is estimated using Kalman filter and is fed into quadrotor inner control loop. For trajectory tracking of arm end-effector an inverse kinematic algorithm is used. The compound system including UAV and arm is simulated with different scenarios in order to verify its satisfactory performance.