Effect of adhesive-layer thickness and curing time on the specific breaking force of the adhesive joint in a space debris capture system

The article analyses studies on capture systems for large-scale space debris objects based on traditional contact methods, including robotic manipulators, harpoons and nets, as well as on adhesion, dry adhesive materials and adhesive compounds. The paper considers space debris objects with kinetic moments close to zero. For experimental investigation, a class of adhesion-based capture systems using adhesive compounds is selected. The study examines the staging of the process, the selection of adhesive compound characteristics, the formation of efficiency criteria, the surface properties of adhesives, the roughness of contacting surfaces, dynamic interaction during contact with the adhesive and loads arising during the towing of an object to a disposal orbit. Moreover, the authors also substantiate the necessity of physical and mathematical modeling of adhesive joint formation, evaluation of specific rupture strength, development of an experimental database and selection of a rational capture system configuration for the space debris object. As an indicator of the resistance of the “capture system surface — adhesive — space debris surface” joint to coaxial normal detachment, the specific rupture strength is adopted, defined as the ratio of the maximum rupture force to the calculated contact area. The article presents the results of assessing the influence of the adhesive layer thickness and the curing time interval on the specific rupture strength under controlled laboratory conditions. The authors by using a laboratory experimental stand investigate the influence of the layer thickness of a two-component epoxy adhesive and its curing time on the specific rupture strength during the coaxial normal detachment of the capture device from a surface simulating space debris. The joint is formed without additional compression. A preliminary regression dependence is constructed on the experimental results, applicable within the studied ranges of factors.