Monday, May 23, 2011
It's important to remember how much might be accomplished with little. Here's an item about gliding aviation pioneers Cloyd and Audrey Artman flying a home-built glider in 1934. A couple of years ago I posted a photo of their glider, perched precariously on a downward-sloping ramp leading off a cliff edge! Hair-raising!
Saturday, May 21, 2011
Once again a leak -- this time, happening suddenly rather than slowly (all pressure vessels have leaks, it turns out, according to the engineering writing I've been reading), so it could be characterized as a 'blowout'. I had the pressure to 3.0PSI for a good while, which was exciting because the pressure held steady--and I bent the arms and legs a few times to see how that effected the pressure, and all was good; and then the dreaded SSSSSSSSS and the suit started to deflate. I'd been using a new neck seal material, and had not cone to know the material well enough to avoid this. I still think I have a good handle on the problem, and am now working on solving it. In the photo I'm using a flashlight to closely examine the breach. It's good to see that this is the one and only place that the suit leaks, and I am confident that I'll sort out the problem.
To give me time to work on the suit, I have a tradeoff; I only get to work on it if I've written 20 pages of my textbook during the week. Friday I didn't warp up till 9pm, but that 'bought' me today's work time!
Wednesday, May 18, 2011
Superb new tool I'm using to help plan the diving expedition this summer; Virtual Ocean has high-res data modelling the sea floor, and many data sets allow you to turn on and off layers of information. Here, you are looking North along the coast of Northern South America; Ecaudor is to the right and 800 miles ahead is Panama. To the left, the Pacific drops off dramatically; vertical scale is exaggerated significantly here, mainly to help visualize the reality. Click to enlarge.
Tuesday, May 17, 2011
While working on the suit, I often spend hours in total isolation, listening to good music. Here is one of my favorite items. Whenever I post a piece of music like this, it isn't a 'cheap post' -- if anyone cares -- it's just me posting a piece of music that seems to reach down and hold onto the exact things I seem to want to hold onto.
Sunday, May 15, 2011
After repeated problems with the helmet-neck interface, I've found the culprit--a poor design decision of my own, rooted in impatience--and now have the problem in hand. It is very simple, and I find a repeated pattern in my building process"
1. research leads to understanding of a principle
2. I rush to apply the principle with a 'get it working' mentality
3. I get the system very close to working, but rushing has led to errors built 'deep' in the design
4. I have to strip down the entire 'build', and rebuild, having learned by working backwards from the full build to find the original problem
So -- good to know that, and be more proactive and intelligent with my design / build process.
In the photos above, I'm doing a gluing episode, inspecting a leak in the rear of the helmet mount, and looking over an array of 1/16th inch steel cables that are at the heart of the problem. With the problem sorted out, I discover that most of what I get at the hardware store turns out to be waste, as it is used in one iteration or another of the system. That's OK, the entire budget so far has been very low, say $20 a weekend, on average,and the knowledge and understanding I'm generating, of course, is priceless.
Tuesday, May 10, 2011
Sunday, May 8, 2011
After a recent dive, Todd and I kept breathing down the remainder of our oxygen-enriched breathing gas; it's a little expensive! And it has a great effect, increasing alertness. Just a few percent more oxygen has a real effect. This is good for diving, though breathing oxygen-enriched air puts hard limits on the depth you may dive, as at a certain depth oxygen becomes toxic, so with this kind of dive you do not exceed a certain depth (depending on the oxygen-nitrogen mix in your tank). This is all very interesting to know, and has significance for the high-altitude balloon project, as in that project I will breathe 100% oxygen. And, before the flights, I will be smart to 'de-nitrogenize' my own body tissues by 'prebreathing' pure oxygen, so even a bit of breathing like this teaches me a little about that process. I'm learning a lot that I can apply to the flying project by progressing in diving!
Sunday, May 1, 2011
After coming very close to 3psi yesterday, I discovered the final pinhole leak. It was exactly where I thought it would be, at a point where carelessness on my part--brought on by my impatience to get the system up to pressure--allowed a part of the suit-helmet mount interface bladder to chafe against a metal element. So, I completely disassembled the helmet mount system and am very confident that with one, last component, costing no more than $10.00, I can bring the suit up to the appropriate pressure. I spent a few more hours making the permanent installation of the oral-nasal mask, happy to know that all of the through-holes on the suit are airtight and that I am very close to a solution.
In the pictures above, I'm working on the neck interface issue (top), adjusting the oral-nasal mask interface while wearing the suit (next image down) and, in the final three images, working out a system for putting the suit on, and taking it off by myself.
As always, finding a problem in the suit, and disassembling the problem component, is the best way to learn. I'm pretty confident that next weekend I will have the system right up to, and holding, the appropriate pressure to survive at my target altitude of 50.000 feet.