Document Type : Research Article
K. N. Toosi University Of Technology, No. 17, Pardis Street, Mollasadra Ave., Vanak Square, Tehran, Iran. P.O Box: 19395-1999, Postal Code: 19991-43344.Tel: (+98 21) 84063284, Mobile: (+98) 9121899445, Fax: (+98 21) 88677274.
Faculty of Mechanical Engineering, K. N. Toosi University of Technology, No. 17, Pardis Street, Mollasadra Ave., Vanak Square, Tehran, Iran. P.O Box: 19395-1999, Postal Code: 19991-43344.
Direct trajectory tracking of quadrotor system in the 3D space is not possible originating from the fact that control inputs are not independent in order to manipulate all flying degrees of freedom. The major concentration of the presented study is to describe the design procedure of a new intelligent algorithm for moving the quadrotor along a trajectory curve in space. The presented algorithm consists of two major parts where in the first one, the desired Euler angles and their associated rate are intelligently estimated by a fuzzy logic controller (FLC) working based on experimentally fuzzyfied rules. The second part of the proposed algorithm is the sliding mode control (SMC) designed for precise tracking of the commanded Euler angles while guaranteeing the robust stability of the quadrotor flight. For simulation of airborne performance of the quadrotor equipped with the proposed trajectory algorithm, a heavy-duty 6-DOF hardware-in-the-loop motion simulator (HILMS) by which all motions of a quadrotor either translational or rotational movements can be precisely evaluated, is designed and fabricated. The introduced HILMS employs one load cell for each arm of the quadrotor allowing the microcontroller to access to motors’ thrust during operation. In this way, while the translational motion is restricted, the position of the quadrotor can be computed along the governing mathematical motion equations. The empirical results confirm stability and trajectory tracking quality of the quadrotor by implementation of the proposed two-staged intelligent algorithm.