Long rant incoming...<p>I'm currently building a quadcopter from parts and I'm writing my own control software.<p>I wasn't really familiar with RC components before starting this project, but I must say I'm impressed with the performance and reliability you get from very low cost motors, ESCs, propellers, gyroscopes and accelerometers.<p>However, I think Li-Po batteries are a huge safety issue. There are multiple factors:<p>* The battery chemistry is very unforgiving. You overcharge, it gets damaged, you over-discharge, it gets damaged. Same for charge and discharge current. The failure mode? Flammable gasses are released and eventually the whole thing sets itself on fire. And that's a fire you can't extinguish using typical means like water or regular fire extinguishers.<p>* All RC Li-Po batteries use a soft shell. If your model crashes the batteries can and will get crushed, which leads to an internal short-circuit, which eventually starts a fire.<p>* No RC Li-Po batteries incorporate Smart Battery controllers (like in laptop batteries) which could prevent overcharge/over-discharge and over-current conditions.<p>There have been plenty of incidents involving Li-Po fires, including whole houses burning down.<p>And still, the batteries don't change. Li-Po makes perfect sense for RC applications because it has great energy density and allows high discharge current. But to me it looks like some simple safety features could make this technology safe enough that you wouldn't have to treat your batteries like small bombs.<p>As a side-note, I've initially tried to use laptop Li-Ion batteries for my quadcopter. Each motor + propeller unit requires almost 12A @ 11V when at maximum speed - quite typical power requirements for a medium-sized quadcopter. I couldn't get more than 16A out of an older 6 cell battery (voltage was abruptly dropping if trying to draw more, so I guess this was the limit of the cells). I've then tried a new 9 cell battery (which was too heavy anyway). The controller on this battery considers 20A discharge an over-current condition and shuts off the output. So I'm stuck with Li-Po batteries and hoping that they won't set anything on fire.<p>I certainly wouldn't feel comfortable with current-technology Li-Po powered vehicles flying around a city without being watched.
Okay HN developers -- when you get done reading the linked article and are finished laughing at the thought of a little helicopter delivering a taco or a bottle of beer, start thinking:<p>* Little helicopters can now lift a substantial weight.<p>* They aren't very expensive.<p>* They're easily controlled, more so than a full-sized helicopter (primarily because of computer-aided controls and GPS guidance). So you don't have to be Chuck Yeager to fly one.<p>* All you need to do is mate the helicopter with a decent camera that can simultaneously beam a picture to the ground for guidance and preview, and take high-resolution pictures on command by way of the radio link.<p>* Uses: real estate (who desperately need a way to take high-quality pictures of houses from above), surveillance, art, video productions, etc..<p>This is an opportunity waiting for someone willing to take it on.
Fun stuff. How about a RC plane dropping off quadcopters loaded with the payload for the last mile? (the copters can meet the plane on the way back or fly home alone. You get the range + efficiency of the plane with the agility of the copter.
I'd really like to see a "you can fly anything commercially that weighs less than 5 pounds and has a terminal velocity below 30mph in freefall" rule. Bigger loads and speeds would be subject to some regulation and licensing.<p>This would cause a Cambrian explosion in development. It would be wild.
I'd prefer something like this:<p><a href="http://www.engadget.com/2009/08/01/urban-mole-robot-could-deliver-your-mail-via-insane-network-of-u/" rel="nofollow">http://www.engadget.com/2009/08/01/urban-mole-robot-could-de...</a><p>- no noise
- no accidents involving people
- less energy needed
- much simpler / robust construction
Is this for real or is it the most cleverly disguised viral advertising campaign for Doritos? I don't see any mention of any other taco brand plus the use of a Doritos branded image...
I really like the idea of multirotors taking off, literally, to be part of a delivery team.<p>Incidentally, I'd really like to be able to use those rotors to recycle things - literally to shred, perhaps, my plastic trash - such that the remaining processed materials can be used in .. say .. a 3d printer.<p>Also, lets get the 3d printer and quadrocopters pretty much working smoothly together so that one provides resources to the other. Oh, no wait, lets just make the 3d printer print quadrocopters, and the quadro's feed the 3dprinters .. and .. well now lets just make a flying recycling 3d printer robot, and be done with it.<p>On Mars. Because if we do it here, the damn thing <i>will</i> take over our planet.
That could be useful for delivering mail in skyscrapers. But The biggest challenge to solve would be finding the way to prevent interceptions/stealing.
Things that fly are really, really dangerous, and the benefits really need to be worth the risks. I don't think a Taco is worth the risk that one of these things goes out of control over the freeway and causes a 100-car pileup. The idea of cheap and plentiful multi copters would make this sort of event inevitable.<p>Of course there may be a much simpler problem: hungry seagulls.
When the drones come to US cities, and it seems they will within a decade, I'll be moving to a smaller town, however small or remote it takes to escape the noise. I'll accept that I'm an old fogey who can't handle "progress".
One nitpick - Bernoulli's principle is NOT why airplanes fly... it's angle of attack. Spirited debate at <a href="http://en.wikipedia.org/wiki/Lift_(force)" rel="nofollow">http://en.wikipedia.org/wiki/Lift_(force)</a>
How about ornithopters? Naively I'd guess they'd come in between planes and quadcopters in both efficiency and agility. Since seagulls can land without a runway, a tacothopter ought to be able to, too.