Adaptive backstepping control design for mass estimation and trajectory control of quadrotor with spherical pendulum

This study focuses a trajectory control problem of a quadrotor, created by combining the dynamics of a spherical pendulum with the dynamics of a quadrotor. A spherical pendulum is a physical system comprising a mass suspended by a string or rod that has the freedom to swing in any direction. During the operation of a quadrotor, the payload connected to it behaves similar to the dynamics of a spherical pendulum. Consequently, it is essential to design a trajectory control problem by considering both quadrotor and spherical pendulum dynamics together, as this constitutes a significant aspect. Due to the varying masses of the payload that are attached to the quadrotor during each take off, the adaptability of the total mass in model-based control design poses a significant challenge. In addition, it is crucial to consider mass adaptation when the payload attached to the quadrotor is released during flight. The proposed Lyapunov based adaptive backstepping controller algorithm can predict the total mass of the quadrotor without prior knowledge of the actual payload. The ability to estimate varying payload masses is crucial for enhancing the quadrotor’s operational flexibility and reliability, particularly in real-world applications where payloads may change dynamically. This innovation paves the way for more versatile, real-world deployment of quadrotor systems in scenarios requiring precise and adaptive control.