Post by: jcarter on March 18, 2010, 07:49:21 AM
I don't care what it costs, I just HAVE to have one!
We have an abandoned airport, all grass and no trees, nearby.
Jane
Post by: krissel on March 21, 2010, 04:29:10 AM
You'll have to build it yourself:
http://www.mikrokopter.de/ucwiki/en/MK-Hexa
http://www.mikrokopter.de/ucwiki/en/HexaKopter
https://www.mikrocontroller.com/index.php?m...ex&cPath=80
http://www.virtualczech.cz/letecke-panorama.php
Post by: jcarter on March 21, 2010, 07:39:29 AM
Though my husband and our engineer son-in-law would just love a project like that.
But money, too much, and building the thing would be more that I could do.
And where we live, we get a lot of wind off the ocean, so flying it would be limited to calm days. But just think of the fun!
Yes, Lets wait till some toy company gets a product like it. The grandkids do have those little $50 'copters that they fly around in the house and harass the kitten and Lilly. Actually Lilly is afraid of them, and I dont want her to crunch one, that would be an expensive crunch.
Its amazing the wonderful toys that kids have nowadays, in our day we had to use our imaginations more.
Jane
Post by: Xairbusdriver on March 21, 2010, 04:26:43 PM
I know where one can get a set for less than $100... 
The most difficult part, for me, anyway, would be justifying the expense and learning enough German to understand the instructions!!!
Justifying the cost could be easier by actually using the thing to sell airborne pictures of property. There are/were (9/11) made a lot of uncontrolled, low altitude flying much more difficult) actually people flying real aircraft and selling images (high quality, of course) to the property owners. People in rural areas, especially like to have pictures from the air, but many businesses could make use of that kind of image for everything from security to building permit needs. It could also be valuable for small towns planing on infrastructure improvements, drainage problems/solutions, etc.
Where's my conversion calculator widget... 
Post by: jcarter on March 21, 2010, 07:19:07 PM
Years ago our tiny town used to hire a small plane to take overhead pictures to see who has built a shed too close to property lines and such petty stuff.
Probably the IRS wants to know if there is a huge boat hidden in somebody's back woods too, who knows? But the town paid thru the nose for those photos.
Once I needed an aerial picture of a swamp in our nearby woods about 20 years ago to prove that it was wetlands, as the town people were too lazy to walk in thru the brambles and underbrush to see that there was actually a swamp and a vernal pond in there.
So I copied the picture from a town employee who I knew, this was BEFORE digital and I had to take the original to a color xerox machine that a friend owned. Presented it in town meeting, and yeah, it got results. Nothing got built on the wetlands! Though I did create a couple of enemies.
Wouldn't this little 'copter have done the job!
On our nearby AFB, they are practicing with these drone surveillance flying critters. Thats one reason we aren't allowed to fly the kids rockets in the woods where the old grass strip used to be any more, its too close by they say.
Lots of fun stuff going on nowadays! Our grandkids are interested in it a lot. Restrictions get worse, fun gets compromised, but we still have fun.
Jane
Post by: tacit on March 25, 2010, 06:59:47 PM
QUOTE(Xairbusdriver @ Mar 21 2010, 09:26 PM) <{POST_SNAPBACK}>
Notice how stable the thing was when lifting that 1 liter bottle? Even though it didn't seem able to dampen the oscillations, it seemed to be able to prevent them going beyond the controllability limits. I assumer that was all based on pure GPS data, but it may actually have some solid state accelerometers on that main board. I know where one can get a set for less than $100...
I know where one can get a set for less than $100... I doubt it was using GPS for that; it has to have accelerometers on board. Notice how it varies the speed of the rotors in hover so that you don't get precession or spinning? GPS wouldn't be able to do that no matter how precise it was; that has to be accelerometers.
And some amazing control software.
Post by: Xairbusdriver on March 25, 2010, 11:12:04 PM
This setup wastes very little energy since all six engine/blade combos are almost always mainly working to lift. The second huge advantage of this arrangement is that the vehicle acts more like a 'standard' aircraft than a helicopter. Note that the blades rotate in different directions, that negates the problem of rotation around the vertical axis that causes problems for most helicopters. Secondly, with a definite 'front, side and rear,' the GPS data can be used as a simple compass to keep the vehicle pointed in one direction or another through the built-in stabilization system. That stabilization system would then need only the two accelerometers for holding the desired attitude. I think this setup would be simpler than using three accelerometers for movement and the GPS simply for returning to a given point. And probably cheaper, also!
But I have no direct knowledge.Whatever design was used, a big problem is fine tuning the the sensor input and output with just the right amount of dampening to prevent self-amplifying oscillations. In a real aircraft, this can happen when the pilot gets slightly behind the aircrafts reactions to control inputs. It is usually seen in the pitch axis with the nose becoming ever higher and lower as the pilot inputs lag the actual aircraft position. A good pilot can recognize this and correct it before it becomes dangerous. A great test pilot can get the aircraft back on the ground safely so he can "discuss" the problem with the engineers!
But with an autonomous vehicle, all this recognition, control movement and dampening must be done by the computer(s), assuming the vehicle is to be allowed to actually maintain a fixed attitude/position/movement for any extended time. My biggest problem with all the RC aircraft I ever flew (or attempted to fly!) was recognizing the reactions of the aircraft purely visually, from outside and often at a considerable distance. The control box (transmitter) usually had absolutely no feedback except for the, "You can't push that lever any further, stupid!" kind!
And, of course, one got even less sensory and visual feedback from what one would get in the vehicle (blood rushing to one's head or feet, one's head slamming against the canopy, etc.). So, it looks like this vehicle has been very well designed to limit it's range of aerobatics to those of "grandma!" Or as we used to say, "the excitement of flying a B-52!" Straight and level, no barrel rolls, Immelmanns, split-S's, etc. "Down" is almost always completely toward the center of the Earth, up is always the opposite of "down." "The nose/tail/wings shall never point at either of those directions!"
The designers seem to have included just enough stabilization to keep the vehicle very stable, vertically so that camera work can be done easily. I doubt they considered carrying liter bottles full of liquid as an appropriate use! But it seems to still have excellent stability, even with a moderately free swinging loadOf course, that still allows for fairly rapid horizontal movement and the main purpose of this machine; vertical movement!
I'd vote for this thing as extremely well engineered and very clever! Not cheap, of course, but neither are MQ-1s or 9s...
Post by: jcarter on March 26, 2010, 06:48:56 AM
Post by: Xairbusdriver on March 26, 2010, 10:56:25 AM
- I'll build.
Post by: Xairbusdriver on March 26, 2010, 01:59:59 PM
BREAKING NEWS!
This vehicle may have strong winds if it tries to fly in the US!
QUOTE
patent #7,679,604 seems to apply not just to any smartphone with an accelerometer, but to any device that uses any method of measuring motion as a means of control. As one patent attorney told me, “It’s obscenely broad.” And it’s old enough to predate many of the motion-sensing smartphones currently on the market.
<Some details>. <Original story>.
Post by: jcarter on March 26, 2010, 07:28:38 PM
Great little video cam on the thing, caught a car thief.
WOW, I didnt realize that this was quite so used in industry.
The toy was what I wanted, but Im sure this will be soon on the market and cheaper.
Fun!!!
Running back to the living room to watch the rest of "Machines" on the SC.
Jane
On another topic, a cop friend told me recently that cell phones are the thief's best friend and the most problematic 'aid' that thwarts police work.
Post by: Xairbusdriver on March 26, 2010, 09:38:07 PM
QUOTE
Running back to the living room to watch
Now, Jane, just because the kids are grown, you should remember to set a good example for their offspring! I can here you now, "Kids, no running in the house!" "But nanaJane, we saw you running just yesterday!" "Just do as I say, not as I..." 
Post by: jcarter on March 27, 2010, 07:06:29 AM