Space elevators and bolas

Status
Not open for further replies.
N

neilsox

Guest
We don't need to return climbers to the Earth's surface as a climber will be worn out having traveled 200,000 miles on the ribbon, if we make the ribbon long enough to throw pay loads to Saturn's moons. We won't need hardly any counterweight if we make the ribbon that long. We can't make it that long unless it is tapered, but we will likely taper even if tapering is not necessary.
I think a capstan is essentially the current thinking, but large diameter rollers or serpentine would add considerable weight to the climber, so should be avoided, unless the simpler design cause excessive wear of the ribbon, or it slips frequently/CNT is slippery like teflon. Large roller diameter could mean the electric motor turns too slow for direct drive. Gears would cause a considerable energy and reliability loss. What are the problems with 500 kilometers per hour instead of 250 kilometers per hour for the average climber speed up the ribbon?
100,000 kilograms = 100 metric tons of ribbon is one kilogram per kilometer, average for a ribbon 100,000 kilometers long. The density of CNT is more than one, but let's figure one for easy arithmetic. One billion cubic millimeters has a mass of one kilogram. One dimension of a kilometer of ribbon is one million millimeters, another dimension might be 1000 millimeters which leaves one millimeter for the thickness; Perhaps only 0.2 millimeter thick at the anchor ship, as it needs to be thicker near GEO altitude where the stress might be 33 tons, or there abouts. The thickness and/or width is considerably less for the starter ribbon. Stretch transients further stress the ribbon to perhaps 66 tons peak?
Perhaps the used climbers can be installed on bolas = short rotovators as the bolas will need frequent repair and upgrading to handle larger pay loads is likely. Possibly the used climbers can also be used on the top end of space elevator 2 and 3 or at a GEO station if we build a GEO station? Possibly we will eventually have a dedicated space elevator for descending only. The climbers need the laser beam to move from the far end to GEO altitude. The far end maybe beyond the effective range of the lasers used to go from the anchor ship to GEO altitude.
A given bola or space elevator has some limitation on the direction of throw, but I presume some fine tuning is practical at the release moment = sort of like the crack of a whip which will be the result of stretch transients traveling on the ribbon. Payloads can be caught by a bola or space elevator and given a new speed and direction, so several of each makes for easier versatility and very little additional delta v with the help of sling shot maneuvers. Catching can also be a contingency if something is wrong thus making space travel more reliable. There is lots more info in the forms at www.liftport.com Neil
 
O

oldAtlas_Eguy

Guest
In the short term bolas are more likely say a bola with anchor mass at 150 miles orbit with 50 mile long arms spinning such that a delta V difference of 3800m/sec is provided. Meaning a launch that gets the payload to 100 miles going suborbital would get picked up and kicked into a eliptical orbit with perigee of 200 miles and apogee of about GEO. That means a launch vehicle would only need to produce a delta V of 4800m/s something a scramjet could possibly get to easily.
 
Status
Not open for further replies.