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#71
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Future of Electronics In Aviation
Le Chaud Lapin wrote:
That very same computer could communicate flight plan to ground, store minute details of entire flight on hard disk and automatically move them to home computer for recap.... Glass panel systems are already on the market that have those capabilities today (except the "auto move" stuff), such as Dynon products: http://www.dynonavionics.com/ Whatever capabilities you think aren't there yet, you can rest assured that avionics makers are already working on fully integrated systems. On Jun 20, 5:16*am, Dylan Smith wrote: Control electronics does exist for GA, it's called an autopilot, and they've been around for a long time (some more sophisticated than others). Some engines are also available with FADEC. These systems are massively expensive, and there is much redundancy. For example, the entire radio stack could be eliminated by a software radio, which controls fed through LCD monitor. That's already being done. I think you need to review what is already available. The software radi costs $1000. The computer would be one of same 2 computers used for other functions. The software development costs for such systems run into the millions of dollars but the number of unit sales is, at best, under a hundred thousand - I suspect more typically a few thousand units. Add in the hardware costs and such equipment can rarely be sold for under a couple thousand. |
#72
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Future of Electronics In Aviation
On Jun 20, 12:06*pm, Steve Hix
wrote: Well, assuming they are experts, each in their respective areas, they would indeed know what to look for. *Also, peer-review (by other experts) is a very good way to check structural integrity of software (or any system). You *really* don't know what is involved in developing verifiably correct software systems, either in time or money. It's *very* difficult and expensive. Which is why so many researchers the world over spend time trying to find mechanized approaches to proving that software is good, or that it satisfies some definition of correctness, etc. Each of these researchers seek what they regard as the holy grail of software engineering - a machine that can help good engineers be better by looking at what they make. As far as FAA certification, if it turned out that verification were prohibitively expensive (greater than $100US million), that would be a problem. In any case, because the material cost of software is $0, the cost of verification would have to be very high indeed before a point would reached, beyond which, it did not make sense to make the software because the market could not support it. -Le Chaud Lapin- |
#74
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Future of Electronics In Aviation
On Jun 20, 10:06 am, Steve Hix
wrote: In article , Le Chaud Lapin wrote: On Jun 20, 6:07 am, Bob Noel wrote: In article , And what analysis techniques would be applied to prove that the resulting software intensive system is adequately safe? The same techniques that employed, in general, by experts to test software. And exactly what level of reliability do you think you'll need to have? Note that the cost can rise enormously for fairly small increases in end product reliability. And so far we haven't said much about what the lawyers will bring to your nifty new product. (Trust me, it won't be something to make you emit small cries of joy.) I don't care how many "fastidious" people look at an architecture or the as-built system, if they don't know what they are looking for and how to find it, the odds of proving anything useful are pretty small. Well, assuming they are experts, each in their respective areas, they would indeed know what to look for. Also, peer-review (by other experts) is a very good way to check structural integrity of software (or any system). You *really* don't know what is involved in developing verifiably correct software systems, either in time or money. It's *very* difficult and expensive. I find writing process control software easy. Can be time consuming...yes, but a good consultant knows *tricks*. Below is a program I wrote that no has ever figured out how it works, it was an exercize is "snug code"...try it, it's fun. Ken ================================================== Ken Tucker (who often posts here) has asked me to post the following little BASIC program that he wrote with his son, Travis, some 15 years ago. It was written in some old dialect of BASIC, with line numbers, but works okay in QBasic, and probably others. What it does is to draw an image of a sphere floating in a starry sky, and then show the sphere being bombarded with meteors, producing craters. After a while, the image does look passably like the moon, or some similar body. If nothing else, it is pretty, and is far more interesting to watch than most screen-savers. Please direct any questions to Ken. I'm just the messenger, as far as this is concerned. dow ------------------------------------------------------- 5 ' Craters. Ken and Travis Tucker. Approx 1988. 10 CLEAR : SCREEN 7, 0, 0, 0: KEY OFF: CLS 12 PCOPY 0, 1: PCOPY 0, 2: PCOPY 0, 3: VIEW PRINT 1 TO 25 21 C = 1: GOSUB 22: C = 9: GOSUB 22: GOTO 25 22 FOR A = 1 TO 100: X = RND * 320: Y = RND * 200 23 PSET (X, Y), C: NEXT A: RETURN 25 DR = 3.141592 / 180: R = 10 30 RANDOMIZE TIMER 35 DIM X(500), Y(500) 40 CIRCLE (160, 100), 90, 8 45 PAINT (160, 100), 4, 8: PAINT (160, 100), 8, 8 100 R = INT(RND * RND * RND * RND * 20) + 1: LO = RND * 170 - 85 105 LA = RND * 140 - 70: C = 8 110 X0 = 90 * SIN(DR * LO) * COS(DR * LA) + 160 112 Y0 = 76 * SIN(LA * DR) + 100 115 GOSUB 300: IF R = 1 THEN PSET (X0, Y0), 14: GOTO 100 120 C = 12: GOSUB 130: PAINT (X0, Y0), 4, 12: GOSUB 600: 125 PAINT (X0, Y0), 7, 12: GOSUB 400: GOSUB 500: GOTO 180 130 N = 0: S = 36 / R: FOR A = 1 TO 360 STEP S: N = N + 1 140 U = R * SIN(A * DR) + LO: V = R * COS(A * DR) + LA 150 X = 90 * SIN(DR * U) * COS(DR * V) + B: Y = 76 * SIN(V * DR) 155 X(N) = X: Y(N) = Y 160 PSET (X + 160, Y + 100), C 170 NEXT A: RETURN 180 PSET (X0, Y0), 15 200 GOTO 100 300 PCOPY 0, 1: DX = X0 - 160: DY = Y0 - 100 305 LINE (DX * 10, DY * 10)-(X0, Y0), 14: GOSUB 600: PCOPY 1, 0 310 FOR A = 1 TO R * 4: X1 = X0 + RND * 4 * R - 2 * R 315 Y1 = Y0 + 4 * RND * R - 2 * R 320 LINE (X0, Y0)-(X1, Y1), 4: NEXT A: GOSUB 600: PCOPY 1, 0: RETURN 400 FOR A = 1 TO N: X = X(A): Y = Y(A) 410 IF X = 0 OR Y = 0 THEN 420 412 PSET (X + 160 + X / ABS(X), Y + 100 + Y / ABS(Y)), 0 420 NEXT A: RETURN 500 FOR A = 1 TO N: X = X(A): Y = Y(A) 510 PSET (X + 160, Y + 100), 14 520 NEXT A: RETURN 600 FOR DE = 1 TO 5: T = TIMER: WHILE TIMER = T: WEND: NEXT: RETURN --------------------------------------------------------- |
#75
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Future of Electronics In Aviation
On Jun 20, 12:27*pm, Jim Logajan wrote:
Le Chaud Lapin wrote: That very same computer could communicate flight plan to ground, store minute details of entire flight on hard disk and automatically move them to home computer for recap.... Glass panel systems are already on the market that have those capabilities today (except the "auto move" stuff), such as Dynon products: http://www.dynonavionics.com/ Whatever capabilities you think aren't there yet, you can rest assured that avionics makers are already working on fully integrated systems. Great! I am going to go out on a limb and speculate that this tendency toward more electronics, not only in the cockpit, but throughout the aircraft, will continue. On Jun 20, 5:16*am, Dylan Smith wrote: Control electronics does exist for GA, it's called an autopilot, and they've been around for a long time (some more sophisticated than others). Some engines are also available with FADEC. These systems are massively expensive, and there is much redundancy. For example, the entire radio stack could be eliminated by a software radio, which controls fed through LCD monitor. That's already being done. I think you need to review what is already available. Someone posted that link above almost a year ago. *The software radi costs $1000. *The computer would be one of same 2 computers used for other functions. The software development costs for such systems run into the millions of dollars but the number of unit sales is, at best, under a hundred thousand - I suspect more typically a few thousand units. Add in the hardware costs and such equipment can rarely be sold for under a couple thousand. Only millions? Under the assumption that a PAV could be driven by a general consumer, as outlined by NASA/CAFE/PAV program, millions, or even hundreds of millions, would be an agreeable cost. As far as hardware, I would use commoditized components ( $1000 PC's). The sensors and actuators would be separate. Dynon might have to sell their units as high as they do because of low volume - they are not selling aircraft, but systems that a pilot might integrate after aircraft is bought. I would instead focus on the entire system, designing to avoid, as much as possible, predisposition toward particular accessory vendor. The idea would be that user chould be able to use $30 Logitech headset if s/he so chooses (actually 2, since they are so cheap), Viewsonic 15- inch LCD panel, Bose or Infinity sound system. With computers so cheap, it would not be unreasonable to have quad-redundancy: 4 motherboards per PAV. Yes, I am sure many experimentalists are and have been doing this for a long time, but there is the burden of the initial design of the aircraft. If the intial cost of the aircraft is $50,000, then no matter what is done, the final cost, after these accessories, will be some amount $50,000. What I am saying is that the entire system, from the outset, should be designed to be low-cost, with the components interchangeable, so that the net cost, with a more-than-modest set of accessories, is $50,000, from the start. -Le Chaud Lapin- |
#76
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Future of Electronics In Aviation
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#77
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Future of Electronics In Aviation
On Jun 20, 11:41*am, Jim Stewart wrote:
Le Chaud Lapin wrote: For XC flights, a computer can do a far better job optimizing fuel efficiency, for example, by controlling control surfaces dynamically during flight. *A computer can also minimize the effects of turbulence, by reactively changing the same control surfaces dynamically. Can you actually cite some numbers and studies or are you just making this stuff up? Not sure what you mean. I haven't given any numbers, so there are no numbers to site. If you are asking if I could show that a computer can do a better job of increasing fuel efficient, that is intuitively obvious. http://en.wikipedia.org/wiki/Fly_by_wire#Fly-by-wire If you Google "fly by wire fuel efficiency stability", there will be many links saying the same thing - a computer can do a much better job than human pilot for these things. It was proven back in the 30's or 40's that after an airplane flies into a pocket of turbulence, it's too late for either a pilot or a computer to make much difference. *The *only* way to fix the problem is with a 20-30 foot boom ahead of the aircraft structure that can sense and react to the turbulence ahead of time. Hmm... Well, generally speaking, if a pilot possesses knowledge of how to handle aircraft, that knowledge can be programmed into the control computer, and whatever it is, a computer can react with greater speed and precision than a pilot could, while remaining within specified constraints. And a computer doesn't get nervous. As to fuel economy, perhaps you can tell me how a computer could tune the radio and get winds aloft readings and pick the best altitude for cruise? *Since it can't, it is unlikely that it could do a better job than a pilot. *OTOH, if you have some concrete evidence to the contrary, I'd love to see it. I cannot not, because no one (that I know of, is doing that yet). There are many ways to d this, using old technology, or the NextGen stuff that FAA is raving about. OLD TECHNOLOGY: With a software radio of appropriate bandset, it is possible to tune to any of tunable frequency of the radio stack. With some powerful software radios, like the ones at http://www.vanu.com, it would is possible to tune to all channels at once (and have power left over to do whatever). COTS software could be used to sample the radio read- back and convert to to digital form. This can be done not only for, ATIS, but any radio source. Note that a software radio, because it contains a DSP, can be used for most of the antiquated signls (VOR). The signal processing power required to process such signals is not suprisingly very low. Once the information is digital form, the rest is easy. But there is more. 1.Unlike a pilot, a computer will never become annoyed by sampling winds aloft on XC flight to hunt for optimal altitude in real-time, the whole time. 2. A computer can also take the information an put up a real-time 3D rendering of such winds aloft on the $200 17-inch LCD panel that you bought from Viewsonic for your cockpit. 3. A computer could also store all winds aloft data for past 5 years of flying on massive 1TB hard disk, that , again, cost $500. 4. A computer can take ATIS readings from local airport and destination airport, plus METARs, etc...all over $20 USB Wi-Fi dongle, one of 7 or 8 that you keep on board, simply because, at $20 a piece, you can afford it. 5. A computer can give you spoken back conditions of target area, remind you at 10-minute intervals with spoken voice fuel remaining in both time and volume. 6. With new Wi-Fi equipment to be released soon, a computer can let you talk to your grandaugther while in flight, via dash-mounted web- cam, and of course, your $30 disposable-but-very-high-quality Logitech headset. 7. A computer would let you take another $40 detachable web cam, and mount it with sucition cups, or more permanently, as you prefer, so you godaughter and son can see what you see as you fly over ground. 8. Some pilots might mount several such cameras around aircraft for various views to help with boredom in flight, or other reasons. There are 100's, if not 1000's of features, that a general-purpose computer + inexpensive, commoditized accessories, can add to flying. What is notable is that the cost of the $1000 PC does not increase. Only the software and accessories change. -Le Chaud Lapin- |
#78
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Future of Electronics In Aviation
Le Chaud Lapin wrote:
I must ask then, if one were to look at a typical GA aircraft, in the year 2100, in your opinion, will it be as devoid of electro-mechanical controls as it is today? What will it look like? -Le Chaud Lapin- In less than 100 years we went from the first plane the Wrights built to the Space Shuttle, the F22 and more importantly for this conversation the Cirrus SR-22. For over half of that century we've told out kids through magazines like "Popular Science" that flying cars are about 10 years away. I personally think you have bought into the "Popular Science" mindset and if you aren't a 15 year old kid (which I'm not really sure that you aren't) you will probably grow out of it. Will there be electro-mechanical controls in future GA aircraft? Of course there will be. The 601XL I'm building has electro-mechanical in it running the elevator and aileron trim. Will the entire wire or push-rod system be replaced? If the parts get to the point where they are of equal or less weight AND the system is as reliable AND cost is equal or less than what is used now the answer is yes. If the Wright brothers were to come back to life today they could look at the SR-22 or the other aircraft I mentioned and understand why they fly how they do. They could probably fly the Cirrus with no more check out than is required of the average guy who is transitioning from a 172. There is a reason for this. Airplanes work the way they do because they are flying in the same environment they were in 1903. They have to overcome the same gravity and they need to be as light as possible for a given job. You have all these grand ideas that replacing everything with electronics will make aircraft easier to fly and cheaper. Yet you have never really told us your idea. You just keep saying things like, "Well, my design will get around that problem." I know you think that there is all this open source software and electronic hardware that is available and cheap. And you have been raised to think that there is not problem that a few silicon chips can't fix. BUT I can pretty much assure you that there are a lot of people a lot smarter than you in the world and some of them work for companies called Lockheed and Boeing and even Cessna and Cirrus. Tell me this. If it could be done cheaper why aren't any of these companies doing it? It isn't like they are making all the money they want and I'm sure any of them would be more than happy to increase the size of the market for aircraft by 1000 fold. I want the flying car I've been promised by "Popular Science" and so do a lot of other people and Boeing and Cessna and Cirrus and the other know it. They just don't know how to make it because with technology available today it can't be made. |
#79
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Future of Electronics In Aviation
Le Chaud Lapin wrote:
Which is the crux of the question: What makes something possible in the future, but not the present? -Le Chaud Lapin- Are you really this stupid? If you have an idea patent it and then tell us about it. Or just shut the hell up. |
#80
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Future of Electronics In Aviation
In rec.aviation.piloting Jim Logajan wrote:
wrote: Have you ever known reliablility and correctness testing to be either easy or cheap, particularly when dealing with life critical systems? No. I now think I probably shouldn't have entered this thread. My own ideas about system development don't appear to agree with either the idealistic and inexperienced/naive views expressed by Le Chaud Lapin or necessarily with your hard earned cynicism. Well, cynicism doesn't quite contain the nuanced meaning that your real position probably entails, so forgive me that it doesn't characterize your full position. I'm a bit on edge at the moment as I am deeply involved in testing a system due to go live in a couple of days which if it goes tits up will embarass a lot of people and cost me a lot of money and if it works means a huge amount of follow on work. So while test cases run I have a far amount of thumb twiddling time to play USENET. I think I might have argued from a different perspective than you, or at least used a different set of arguments, not that I nessarily disagree with your general thrust. I wouldn't, for example, have used some the anecdotes you used - which for some reason bothered me, but in retrospect it isn't like any of us get paid to insure every post is rigorously logical! Exactly, not to mention the fact that anything past the most simplistic of arguements and examples are going to fly right over the head of Le Chaud Lapin. -- Jim Pennino Remove .spam.sux to reply. |
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