Nonobserver-Based Fixed-Time Output-Feedback Control for Uncertain Bridge Cranes System

Bridge cranes system (BCS) displays a high degree of nonlinearity and is underactuated, making the control problem significantly more challenging. Most of the existing control algorithms for the BCS can only achieve asymptotic stabilization, which results in the control speed and precision being challenging to meet the demand of current production and application. This article is concerned with the fixed-time stabilization control for a class of BCS subjected to unavailable velocity signals in the measurement and unknown disturbances. By skillfully combining the Lyapunov method and the system homogeneous theory, a novel output feedback fixed-time controller is designed to ensure the trolley reaches the target position in a preset time while restraining the load swing quickly. The salient characteristic of this control method is that any observer is not designed such that the control complexity is reduced. At last, we demonstrate the plausibility of the proposed control approach through simulations and practical experiments.