Research on the Control Algorithm of Coaxial Rotor Aircraft based on Sliding Mode and PID

Abstract

In this paper, a sliding mode PID control algorithm of coaxial rotor aircraft has been proposed. After that, Adams/MATLAB simulation and experiments were used for verification. The results show that this control method can achieve satisfactory results. Firstly, when considering of the aerodynamic interaction between upper and lower rotor, it is difficult to establish an accurate mathematical model, and the aerodynamic interference between the upper and lower rotors and the brandishing motion of the blades are calculated by using the blade element theory and the dynamic inflow model, and the other parts which are not accurately modeled are compensated for by the control algorithm. Secondly, the sliding mode control algorithm and the PID control algorithm are combined to control the attitude of the aircraft. Among them, the PID control algorithm is used to establish the relationship between attitude and position, so that the aircraft can fly and hover more steadily. Thirdly, the three-dimensional model of the aircraft was imported into Adams to establish the dynamic simulation model. Then, the controller was established in Simulink, after that, and then the controller and the dynamic simulation model were combined for joint simulation. And the sliding mode PID control algorithm has been compared with traditional PID control algorithm through the simulation. Finally, the sliding mode PID control algorithm is verified by the experiment compared with the traditional PID algorithm. The results verify the superiority and practicability of the control method designed in this paper.involved in this paper is significantly reduced, being more portable and suitable for use. The coaxial rotor aircraft we chose is being developed independently by our laboratory. The maximum takeoff weight is about 8 kg and the rotor diameter is about 28 inches. After folding, the size of the fuselage is less than 120 mm in diameter and the full length is about 100 cm. It is placed in a narrow and long rocket compartment for transportation and delivery, and the folded rotor is simpler and more reliable than the folded fuselage design [2].Compared with other kinds of aircrafts, the research on coaxial rotor aircraft is relatively less. Automatic Control Laboratory of Tlemcen presented a nonlinear control method based on sliding mode control (SMC) for the position and the attitude tracking control of a small coaxial-rotor UAV subjected to uncertainties and aerodynamic disturbances [3]. Recently, they proposed a hierarchical controller based on a new disturbance observer with finite time convergence to solve the path tracking of a small coaxial-rotor-typs UAVs despite unknown aerodynamic efforts [4],however, the advanced algorithms they studied are still only at the simulation level, without experimental verification. There is still a long way to go before engineering applications; the French-German Research Institute of Saint-Louis presented a comprehensive design of a Gun Launched Micro Air Vehicle (GLMAV) which is a new Micro Air Vehicle (MAV) ...

Design and development of a novel multirotor configuration with counter-rotating coaxial propellers

“…Although the configuration developed in the current study differs from the ones developed in 6 and 7 due to the usage of small propellers to control the multirotor attitude, it shares certain advantages with the configurations developed in those studies. In 6 , the “high-speed cruise” mode was mentioned as one of the most remarkable features of the configuration.…”

“… Utilization of fuel power systems and hybrid power supply systems 5 . Development of novel configurations: Exploration of new arrangements, such as using larger propellers to generate the majority of the lift force 6 , 7 , and the integration of fixed wings alongside rotors 8 , etc. …”

“…A few studies have explored the development of multirotors featuring two large propellers in a coaxial configuration 6 , 7 . In 6 , the aircraft, which is illustrated in Fig.…”

“…In study 7 the method for controlling lift and the yaw axis mirrors that of study 6; however, the aircraft in this study employs a swashplate mechanism to manage the roll and pitch axes. The primary objective of the study was to develop a controller algorithm using sliding mode PID, with less emphasis on the design and development process.…”

Fuzzy Self-tuning Tracking Differentiator for Motion Measurement Sensors and Application in Wide-Bandwidth High-accuracy Servo Control

“…Signal differential estimation is essential for wide-bandwidth high-accuracy servo controls [1]. High-precision measurement of position, velocity and acceleration signals is a necessary feedback information for various control strategies, including classical PID control [2], sliding mode control [3], and so on. However, due to the limitation of measurement mechanism, some motion measurement sensors, such as velocity sensors and acceleration sensors, have certain measurement noise which limits the accuracy of the measurement.…”