Dynamics modeling and nonlinear attitude controller design for a rocket-type unmanned aerial vehicle

Area of Science:

• Aerospace Engineering
• Control Systems
• Robotics

Background:

• Rocket-type unmanned aerial vehicles (UAVs) require sophisticated control systems for stable flight.
• Gimbal-based coaxial rotor systems (GCRS) offer thrust vector control (TVC) but present complex nonlinear control distribution challenges.

Purpose of the Study:

• To develop and validate an altitude and attitude control system for a novel rocket-type UAV utilizing GCRS for TVC.
• To address the highly nonlinear and tightly coupled control distribution problem inherent in the GCRS actuation.

Main Methods:

• Derivation of attitude flight dynamics for the UAV.
• Development of a Proportional-Integral-Derivative (PID) control algorithm using Linear Matrix Inequality (LMI) for robust stability.
• Application of the Levenberg-Marquardt (LM) optimization method to solve the nonlinear control input distribution problem.

Main Results:

• Successful implementation of a control strategy to track desired attitude trajectories.
• Effective solution of the nonlinear inverse mapping problem for GCRS actuator outputs.
• Demonstrated attitude stabilization and altitude tracking capabilities, even under disturbances.

Conclusions:

• The proposed GCRS-based TVC system is a viable approach for rocket-type UAVs.
• The combined PID and LM control algorithms effectively address the complex control distribution challenges.
• Numerical simulations confirm the system's ability to achieve robust attitude and altitude control.