Climber

This Andromeda Connection website wasn't always an invention showcase. It started out as an online log outlining the progression of my part in the 2007 Space Elevator Challenge.

The space elevator is just what it sounds like; an elevator from earth to space. Or more accurately, a nanocarbon ribbon that stretches from the earth's surface to a point 62,000 miles into space with a station located at the geosynchronous orbit distance of just over 22,000 miles.

My task was to build a robot climber to climb a 3" wide ribbon 1 km. high. There were several teams competing that year for the then $2M prize. I had a winning strategy, a winning design, but just one problem; the other teams were actual teams consisting of five to more than a dozen members. My team consisted of me. The last month or so my brother-in-law, an actual rocket scientist, came to help, but it was too late. I just didn't have time to complete the project. Oh well, I had a hell of a lot of fun doing it and went to the event to see it and show off my creation even though it was incomplete.

I've put together this page just to show where all this started.

It is fortunate for me that I have these pictures. Before my Lyme disease I was able to create anything I wanted. But I almost always forgot to take pictures. Enjoy!

Here are a couple of YouTube videos describing what the space elevator is all about:

A better way to get to space: Dr. Michael Kelzenberg at TEDxWSU 2014
An Elevator to Space: Markus Landgraf at TEDxRheinMain

Beginning
Beginning construction of climber 1
Climber 1
Climber 1 main frame almost done
Climber 1
Climber 1 main frame in open position. I'm working on this outside my welding shop.
Drive on climber 1
Drive system mounted on climber 1
Fiber
A complex fiber optic arrangement to carry light to solar cells.
Climber 1 core
The center core of climber 1
Big shipment
Just returning from the airport with the six large spotlights from China

Out of the box.
Gears
All of the gears for the drive system had to be cut by hand. Two 12V Dewalt drill motors were used for power. I ended up not using the transmissions opting for more solid gears instead.
CuttingGears1
Cutting aluminum gears on milling machine with home made gear cutter
Cutting Closeup
Close up of cutting gears. This style of gear cutter lets you make a matched set of gears with a single cutter just by properly calculating the various diameters. This cutter I made was plenty good enough for making aluminum gears but with my limited knowledge of metallurgy and having never had any official machining training, it wasn't good enough to make steel gears. An upgrade was needed...
Gear Cutting Set
I chose to make the gears from aluminum for weight reasons but in repeated testing they were wearing down too fast. These new gear cutters allowed me to make gears from steel. Expensive for the set but at least I was able to make the arbor.
Steel gear
Steel gear with thin web and holes for weight reduction.

The tall frame pictured above was proving to be cumbersome and heavy - the more weight, the more power needed, the more solar cells, adding more weight. In my studying of various types of solar cells I came up with something I called a "Light Trap". I was incorporating this concept in the original design, but never really tried it. The tall design was mostly intended to evenly distribute the available light to maximize efficiency. I decided to run actual tests to see how much this concept would increase efficiency. After running the tests I found the concept actually increased efficiency by 18.5%. That's huge! I didn't take any actual pictures of the tests, but clicking on the image above will give you an explanation.

Armed with this new info I set out to design another climber. Taking into account previous calculations and tests such as motor efficiency, material weights, etc. I came up with a design that is substantially smaller and lighter while still using the same drive system. The "Flying Saucer" was born!

The ribbon that the climber climbs has to go through the center of the climber so the entire unit is designed in two parts. Here is an shot of the inside. This allows the climber to be opened and wrapped around the ribbon. The solar cells will be attached to the upper half of the upper section. The inside looks yellowish here because of the protective film which will be removed at the last minute.

In order to test the climber an outdoor test track was needed. Here is the beam in the trees from which the ribbon was susspended.

A couple of sail boat winches borrowed from a friend served to hoist the heavy beam into place.

The Flying Saucer being tested on the outdoor track. A 12V RV battery was used as a power supply. Unfortunately the battery was old and proved to be too weak to do a proper test, but the test did tell me what I needed to know.

Spotlights are designed to focus a fairly narrow beam, but these spotlights did this by cutting out most of the beam. I needed as much energy coming from these lights as possible. A way around this problem - a way to get all available light from the spotlight in a narrow beam - was with a lens. But where to get such a lens at a decent price, and how to know what focal length the lens should be? The solution was an adjustable lens. Above is a liquid lens made from Plexiglas, Mylar and water. By adjusting the water pressure (with a syringe in this prototype) I was able to successfully create an adjustable lens.

The next problem I ran into was the spot lights. I should have known better than to trust something made in China. Turns out they produced far more heat than light. Even all six together were not going to be enough, not to mention beaming that much thermal energy into the climber. Pictured here is a four stage solar concentrator. I was planning on using four of these.