Cooperative Mobile Robot Swarm for Non-Destructive Structural Inspection Using Backstepping–SMC Control

Non-Destructive Testing (NDT) necessitates thorough and dependable evaluations of structures within intricate and cluttered settings. Utilizing robotic swarms presents a feasible method to automate such processes, offering synchronized, efficient, and scalable inspection features. This document introduces a simulation-based system tailored for autonomous NDT inspections, employing a collective of differential-drive mobile robots developed in MATLAB/Simulink. Each individual robot is managed through a hybrid Backstepping–Sliding Mode Control (SMC) approach, which guarantees accurate trajectory adherence and resilience against disruptions. A leader–follower arrangement orchestrates the swarm, enabling follower robots to sustain ideal relative placements for effective coverage. To facilitate safe movement near inspected areas without jeopardizing the formation's stability or trajectory precision, obstacle avoidance is incorporated using an artificial potential field technique. The simulation outcomes depict the paths of both leader and follower robots, the preservation of the formation, and the successful navigation around obstacles in a cluttered environment that mirrors typical industrial or structural conditions. Metrics assessing performance, including root-mean-square tracking error, deviation in formation, and inspection coverage, validate the effectiveness of the introduced method. A comparison between configurations using a single robot and those using a swarm reveals considerable advancements in both inspection efficiency and durability. The outlined framework offers a thorough simulation exploration that demonstrates how cooperative mobile robot swarms, directed by Backstepping–SMC control and formation tactics, can notably improve autonomous NDT operations. This research establishes a basis for the forthcoming development of multi-robot NDT systems applicable in industrial contexts.