Solar-pumped laser power transmission, a way to dramatically decrease launch costs?
in [Physics]
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From: William Mook on 15 Feb 2010 15:32 On Feb 15, 4:00 am, Pat Flannery <flan...(a)daktel.com> wrote: > Fred J. McCall wrote: > > Venture capitalists > > are smarter than to hand money to someone like you. > > I don't know about that; remember the Moller Flying Car that's been > "entering production later this year" for around twenty years now. > Wait till you see their new one, that must be made for Nick Fury and > SHIELD to replace the flying Porsche 904's that Stark Industries made > for them back in the 1960's:http://www.moller.com/index.php?option=com_content&view=article&id=12... > Heck, they'll have that thing flying by next week. > Even if it can't get airborne it will make the ultimate riding mower. :-D > > Pat I actually paid Moller for a franchise back in the 1980s. I'm still waiting for my inventory. lol. That was when they needed only $5 million to finish things off. Moller used to make money selling mufflers, but sold that business to build skycars. He's making money selling contra-rotating ducted fans powered by wankel engines. http://www.moller.com/ He has gotten into trouble with the SEC for his claims over the years.
From: William Mook on 15 Feb 2010 15:42 On Feb 15, 6:17 am, Pat Flannery <flan...(a)daktel.com> wrote: > Scott M. Kozel wrote: > >> Solar sails are ideally suited for this mission. I am considering > >> fully reusable vehicles capable of putting 1,000 metric ton payloads > >> on orbit for very little cost per ton. This sort of vehicle is > >> required to build any sort of orbital or lunar or Martian > >> infrastructure. Its well within our capacity to build it. > > > The orbital velocity of a 24-hour circular orbit 2 million miles > > radius from the center of the Sun -- (3.14 * 4,000,000) / 24 = 523,333 > > miles per hour. > > > That is the velocity you would have to attain. > > Can a solar sail even be tacked towards the Sun? Yes. You can accelerate along the orbit, raising the apohelion, by tilting the sail 45 degrees away from the sun, or slow along the orbit, lowering the perihelion, by tilting the sail 45 degrees away from the sun, in the other direction, or change the inclination by tilting the sail up or down up to 45 degrees. > Ships tack by using the force generated by the wind on their sails to > head into the wind at around a 45 degree angle as their keel keeps them > from being blown backwards by passing through the denser medium of water. > But in space there is nothing like a keel or denser medium to pass it > through. So? Light follows the laws of optics for reflections. Namely the angle of incidence equals the angle of reflection. So, thrust is always normal to the reflective surface. So, by reorienting the surface - thrust vectors may be reoriented, which then changes the veclocity vector of the vehicle. > > Pat Light pressure is created by reflecting incoming light. Given the nature of light reflecting from a mirror, angle of incidence equals angle of reflection. So, you always have force normal to the surface - since vectors add like vectors. So, by re-orienting the surface, you orient the thrust. Since thrust is proportional to light intensity you have a cosine function of the half-angle in the thrust vector as it points away from the center of the sun. So, pointing the thrust vector 45 degrees -away from the sun, involves turning the sail 45 degrees relative to the sun - and reflecting light from the sun along the orbit. This gives 0.707 the intensity of full on, and 0.707 of the total is along the orbit, - so, 0.500 of the thrust obtained by reflecting light straight back at the sun may be applied to slow or speed up a spacecraft in this way. As the thrust vector approaches 90 degrees nearly 100% of the thrust vector is directed along the orbital tangent (which is what is desired for Hohmann maneuvers) but total thrust drops to zero at 90 degrees. Maximum is around 45 degrees.
From: William Mook on 15 Feb 2010 15:56 On Feb 15, 9:46 am, David Spain <nos...(a)127.0.0.1> wrote: > William Mook <mokmedi...(a)gmail.com> writes: > > The town isn't taking any risk with a contingent purchase agreement. > > A five year development cycle and a monthly report of progress will > > give them - and the risk taking VCs - a clear idea of progress as it > > occurs. > > Mr. Mook, > > How do you prefer to be addressed, Bill, Will, William? I hate formal last > name greetings. You may call me Mr. Mook, that's fine. > The problem with VCs (and having been at *four* startups believe me when I say > I know whereof I speak) is not so much what happens when you show progress but > when you show lack of progress. I invented the computer based cash register and brought it to market. http://www.scribd.com/doc/21646352/Mook-POS-Patent Along with the credit card scanner in the gas pump. I also invented a golf ball that changes color and brought it to market, and sold the company for quick profit http://www.scribd.com/doc/21970436/Spin-Communicating-Ball And have done a number of other things that have made significant money. I have spent the last 16 years developing solar energy systems of exceedingly low cost - and I am in the process of bringing them to market http://www.scribd.com/doc/20024019/White-Paper-to-Mok-FINAL-1 http://www.scribd.com/doc/20024088/White-Paper-Wafer-Fab http://www.scribd.com/doc/20023580/Testimony-Ohio-House-of-Representatives-in-Support-of-SB-221 http://www.scribd.com/doc/20019383/July-11-2009 http://www.scribd.com/doc/26890687/CH2MHill-Study http://www.scribd.com/doc/26855139/1000-Solar-Way-Purchase-Signed > All complex engineering projects will have > schedule 'slips', the question is how well you can quantify and manage the > slippage. Well, I wouldn't be so passe' about the slips in the first place - things need to be managed and quantified from the outset. > If the slippage is due to something that is more of a resource issue Then the fault is in the original planning phase. > or of a type with a known 'engineer-able' process to a fix that is one thing, Then the fault is in the original design phase. > but if it requires further R&D to come up with an answer that is another. Then the fault is in the R&D definitions - someone lied somewhere to get funding and didn't really know the answer. All open issues must be resolved before one goes to market. > VC > capital is *NOT* known for its patience. <shrug> I've never had a problem. > Worse still, I have had the experience of having brought a product all the way > from paper to prototype to production and *still* have the company canned when > the company's capitalization (revenue - expense) ramp up was unsuitable to the > VC's timetable, even *after* they had provided the initial investment. In > other words, they were completely willing to write off a +$30M investment to > avoid putting in another $30M because we would not be able to hit their 2 year > limit on how much revenue we'd need to be generating. That's the fault of having no balls during negotiations. > Quarter over quarter > sales growth (20%) did not matter, nor whether or not the company achieved a > profit, it was all about their on-time exit strategy, in other words, could > they flip the company at a 40% ROI after two years?! That's the fault of a poor dating procedure before marriage. > I can't image what it'd be like at $300M! So, you've never done billion dollar deals then? > At those figures you'd need > corporate institutional investors, Obviously. > and that is a very hard sell. Not if you do your homework rightly. > These days > you just won't find the typical high-tech VCs willing to pony up that kind of > money. VCs haven't the experience in the energy business needed to do well, and alternative energy doesn't understand the energy business anyway - so, the order of battle is of key. Fortunately there are a lot of 'wildcat' investors out there that have a deep background in developing energy projects. The key is to look like one of those and have similar cash events that allow one to cash out - and be prepared to fight over what happens if those change. > You need to figure out ways to boot-strap at well under $100M, (like $30M or > less) with a two year ROI at 40% if you want VCs to help you, trust me. Why should I change my successful business model just because you don't have experience needed to understand the financing requirements of the business I'm in? Multi-billion dollar projects routinely get funded in the energy business with less than 20% chance of success. > Dave I believe my experience exceeds yours at this point. I understand that you are clueless. That does not mean I am.
From: Scott M. Kozel on 15 Feb 2010 19:52 William Mook <mokmedi...(a)gmail.com> wrote: > > "Scott M. Kozel" <koze...(a)comcast.net> > > > That is the velocity you would have to attain. > > BASIC ASTROGATION > > The vis-viva equation gives you the velocity of an object in an orbit; Interesting calculations snipped ... I can see that you have put a lot of thought into this ... one question, what is temperature at 2 million miles from the Sun? Mercury at 35 million miles is about 800 degrees F on the surface at the equator, hot enough to melt lead.
From: Pat Flannery on 15 Feb 2010 22:57
Scott M. Kozel wrote: > I can see that you have put a lot of thought into this ... one > question, what is temperature at 2 million miles from the Sun? > > Mercury at 35 million miles is about 800 degrees F on the surface at > the equator, hot enough to melt lead. (Note to self - don't use solder on near-sun solar power gatherer.) :-) Pat |