guest blogger john hare
A variant on the compound tether is the electrodynamic tether with rotovator. In this one a long electrodynamic tether has solar panels and other counterweights high enough to get the center of mass to a 135 minute orbit with the bottom end at LEO altitudes. With the bottom end at 2,500 m/s below local orbital velocity, a rotovator hub is attached with a tip speed of 2,500 m/s. The rotovator tips will cycle between 5,000 m/s below orbital velocity and local orbital velocity.
While this does not service the transportation hubs as in the earlier post, it might provide a way of getting a lot of volume into LEO. Two advantages to the system here compared to the last, electrodynamic tether can provide the reboost without propellant expenditure, and it is easier to visualize and model.
As before, this is amatuer speculation.