Appointed-Time Disturbance Observer-Based Control for Multiquadrotor Suspended Transport System Within Virtual Trajectory

Abstract

This article designs a distributed formation control method utilizing an appointed-time disturbance observer to address the challenges of cooperative transportation along a virtual trajectory in a multiquadrotor suspended transport system under unknown disturbances. Initially, a desired symmetric formation structure is established using the virtual trajectory as a reference signal for the formation controller design. Subsequently, a disturbance observer with appointed-time convergence characteristics is developed to estimate and effectively compensate for unknown disturbances within the controller. The controller is then designed based on an appointed-time performance function, which defines the dynamic performance index. This approach integrates adaptive appointed-time sliding mode control with performance constraints to achieve distributed formation control, ensuring the avoidance of internal collisions and maintaining coordinated transportation along the virtual trajectory. Lyapunov stability analysis demonstrates the uniform ultimate boundedness of the closed-loop system. Finally, numerical simulations and physical experiments are conducted to validate the effectiveness of the proposed method.