Cooperative Load Transportation of Multi-Drones Based on Disturbance Observer and Formation Control

With the increasing reliance on unmanned logistics through drone technology, the challenge of efficiently transporting heavy cargo has emerged. The study delves into the complexities of multi-drone cargo transportation, focusing on the stability of transported goods. To address the limitations of single drones in carrying heavy loads, we propose the integration of a disturbance observer-based (DOB) controller to effectively estimate disturbances without intricate calculations or additional sensors and specific knowledge of the cargo’s characteristics, thereby enhancing cargo movement stability. This estimated disturbance is countered by dynamically adjusting the drone’s inclination, reducing the cargo swing angle, and maintaining formation to ensure a balanced weight distribution during transportation. In addition, we investigate the impact of positional accuracy on overall performance and find that a PID controller combined with the DOB controller outperforms both standalone PID control and the combination of PID and formation control relative to the desired reference. Real-world experiments, which have rigorously validated the efficacy of our proposed method, demonstrate its ability to neutralize disturbances and stabilize drones within constrained areas quickly, instilling confidence in its reliability and effectiveness.