Building an "Escape Portal" with Tethers Fixed in Asteroids

The main idea of this paper is to propose the construction of an "Escape Portal" to send a spacecraft to the exterior planets, or even to make it escape from the Solar System, using a Tethered Sling Shot Maneuver (TSSM) with an asteroid. The construction of this portal allows an unlimited number of maneuvers with the same tether, which is very interesting when considering a possible use for small satellites. This structure would be formed by a tether that remains fixed in an asteroid. At the other end of the tether, a large net is fixed, such that the only action required from the spacecraft to make the TSSM is to hit the net. The net can have a mechanism to open a passage to release the spacecraft when the desired rotation is obtained. This technique would avoid some of the problems that appear when assuming that the spacecraft needs to carry a tether on board that would be released to hit the asteroid just before the maneuver.