Design, dynamic modelling and experimental study on a tether-net system for active debris removal

The tether-net capture is considered to be a promising technology for active debris removal, due to its advantages of low cost, large capture range, and high stability. In this paper, we aim to address problems of mechanism design, dynamic modeling and experimental verification for a tether-net capture system. A compact tether-net capture system is initially designed. An improved dynamic model considering torsion of the tether-net capture system is innovatively developed on the basis of the concentrated mass method and the Kelvin-Voigt model. A collision detection model is followed to examine the collision between multiple objects and to determine the contact force. Additionally, the tether-net deployment and object capture are simulated, and a dragging simulation of the assembly of the tether-net capture system and the space debris is conducted using this model. Finally, ground tests for vertically and horizontally capturing a balloon are performed. The simulation results demonstrate that the improved model is accurate to describe the dynamic characteristics of the tether-net capture system. The prototype shows a capability to successfully capture objects.