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Doesn't sound to me as such a great achievement. Sure, it's a small RC ornitopther, but it will hardly be the first, and as someone pointed out a prop will work better, even at small sizes. There are quite a few examples of planes under 3 grams on the RCGroups indoor forums, in particular these entries: http://www.rcgroups.com/forums/showthread.php?t=596219 (mg range brushless motors) http://www.rcgroups.com/forums/showthread.php?t=841147 (solar powered < 500 mg project) http://www.rcgroups.com/forums/showthread.php?t=892415 (390mg Plane - Video)

Doesn't sound to me as such a great achievement. Sure, it's a small RC ornitopther, but it will hardly be the first, and as someone pointed out a prop will work better, even at small sizes. There are quite a few examples of planes under 3 grams on the RCGroups indoor forums, in particular these entries: http://www.rcgroups.com/forums/showthread.php?t=596219 (mg range brushless motors) http://www.rcgroups.com/forums/showthread.php?t=841147 (solar powered < 500 mg project) http://www.rcgroups.com/forums/showthread.php?t=892415 (390mg Plane - Video)

Doesn't sound to me as such a great achievement. Sure, it's a small RC ornitopther, but it will hardly be the first, and as someone pointed out a prop will work better, even at small sizes. There are quite a few examples of planes under 3 grams on the RCGroups indoor forums, in particular these entries: http://www.rcgroups.com/forums/showthread.php?t=596219 (mg range brushless motors) http://www.rcgroups.com/forums/showthread.php?t=841147 (solar powered < 500 mg project) http://www.rcgroups.com/forums/showthread.php?t=892415 (390mg Plane - Video)

The smallest I am aware of is Angry Monk's world record 3.125" span 390 micro gram plane
http://www.rcgroups.com/forums/showthread.php?t=892415

or

Martin Newell's Shark at 2.65" span and 0.495 gram
http://mnewell.rchomepage.com/Planes/Shark/Shark-1.html
Flight time is "A few minutes"

As is usual whenever electric cars comes up, it's time for some mythbusting.

No, they don't increase pollution and overload the grid; precisely the opposite (more specifically, the only pollutant that goes up is particulate matter, and it's displaced away from population centers. NOx and SOx remain the same, CO2 drops, and CO and VOCs are nearly eliminated; the grid gets to make use of its surplus off-peak capacity and, with smart charging, can eliminate the supply/demand fluctuations that are currently so troublesome).

Yes, they are far more energy efficient than their alternatives.

No, modern batteries don't take forever to charge. The phosphates, titanates, modern spinels, and others can all charge in 5-20 minutes, given sufficient power.

Yes, fast chargers exist. The SAE J1772 standard covers Level 3 charging at hundreds of kilowatts. Yes, chargers as strong as 250kW exist. Yes, there's already a network of 60kW Level 3 chargers in place around Oahu. Install one yourself.

No, the batteries are not toxic. Current li-ions are only mildly toxic, and this only because of their cobalt-based cathode. The phosphates and spinels eliminate this cathode in favor of nontoxic elements.

No, lithium is not running out.

Yes, the batteries last a long time. The phosphates last 7000+ gentle cycles, having only 20% capacity loss after 1000 abusive cycles. The titanates? 20,000 cycles. Accelerated aging tests suggest LG Chem's packs will last 40+ years in typical use.

Yes, both rapid charging stations and EVs make financial sense.

Hmm, did I miss any?

If you know much about the state of UAVs these days, research and development is going mainly into autonomous vehicles. Human controllers are definitely in the loop, defining waypoints, orbits, and so forth, but they aren't being flown directly by pilots, unlike the current crop of *military* UAVs that are in operation right now. The goal of UAVs is to have the plane take off, fly a particular mission, do something, and then fly back and land. All without a pilot controlling it. This isn't some future thing. This is what UAVs in research labs are doing right now.

You can bet that the next generation of military UAVs are definitely unmanned and pilot-less, though not uncontrolled, agreed.

With commercial companies getting into UAV stuff for civilian purposes (monitoring land and crops, mapping developments for a contractor or something, etc), the FAA is probably right to worry. I am concerned that the FAA's typical over concern will negatively impact the hobby field where UAVs are being developed and flown at low altitudes for fun by quite a few rc computer hackers[1]. So many neat things are being done by hobbyists [2] and it would a real shame if the FAA shut them all down overly ridiculous concerns like terrorism.

[1] http://www.rcgroups.com/uav-unmanned-aerial-vehicles-238/
[2] http://paparazzi.enac.fr/wiki/index.php/Main_Page

[quote]Citations please? Everything I've been able to find about LiP cells has been written by (or sourced from) somebody trying to sell them, apart from this IOP article, which only tests the cells through 100 charge cycles, and also notes some strange behavior with regard to the internal impedance of the cells after just 30 charge cycles.[/quote]

What, exactly, are you looking for? Real-world use? Sure, here you go. Or perhaps this. Or almost anything from that site. And remember, these are amateurs, and the sort of loads they're putting on these cells are an order of magnitude more than a BEV will ever do. As for "people trying to sell them", in the Volt, they're going to be having a very long battery warranty (they want to be able to ensure a minimum 10 year lifespan), so they *better* last, or GM's going to lose a fortune.

The company refuses to release crash-test data, despite claiming to have done several, and to have more or less finalized their design.

What on Earth are you talking about? The company has not done *any* physical crash tests; that's for late this summer/early this fall, once their new factory comes online. They *have* done crush tests and digital crash tests. They have pictures on their website from one of the digital crash tests and have described the overall results (they use the same crash software that BMW does). They also have a video tour that includes their crush rig.

Where are you getting this from?

[quote]Citations please? Everything I've been able to find about LiP cells has been written by (or sourced from) somebody trying to sell them, apart from this IOP article, which only tests the cells through 100 charge cycles, and also notes some strange behavior with regard to the internal impedance of the cells after just 30 charge cycles.[/quote]

What, exactly, are you looking for? Real-world use? Sure, here you go. Or perhaps this. Or almost anything from that site. And remember, these are amateurs, and the sort of loads they're putting on these cells are an order of magnitude more than a BEV will ever do. As for "people trying to sell them", in the Volt, they're going to be having a very long battery warranty (they want to be able to ensure a minimum 10 year lifespan), so they *better* last, or GM's going to lose a fortune.

The company refuses to release crash-test data, despite claiming to have done several, and to have more or less finalized their design.

What on Earth are you talking about? The company has not done *any* physical crash tests; that's for late this summer/early this fall, once their new factory comes online. They *have* done crush tests and digital crash tests. They have pictures on their website from one of the digital crash tests and have described the overall results (they use the same crash software that BMW does). They also have a video tour that includes their crush rig.

Where are you getting this from?

it's called the air hogs aeroace, it's sold at toy's r us, made by a chinese company called silverlite, and modded by millions of us who dont want to spend more then US $29.95 to fly. the largest problem with planes this small is wind.

http://en.wikipedia.org/wiki/Aero_Ace

for those of you who desire a new addiction check out this micro rtf forum, it has many of the designers of toy planes posting on it, not to mentions many of the members own designs reusing the electonics from the toy planes.

http://www.rcgroups.com/forums/showthread.php?t=401484

It's definitely a nifty little RC vehicle, but why not make it more remote and control it with a live video feed? Coupled with gyroscopic input from a video headset, ala here, this thing could be controlled from the dude's bar. I mean, when you watch the CNN video, it does seem a bit dorky to have this guy walking 10 feet behind the robot. I'm sure the good people over at RC Groups would be happy to help him out.

Plus, you know, if the thing really pisses off a dealer, it'd be nice to be a good distance away.

Today, hobbyists, i.e. skilled individuals without govt./corp. funding are able to make radio-controlled (or at least infrared controlled) electric-powered aircraft that weigh less than a gram. Many of these hobbyists frequent this forum: http://www.rcgroups.com/indoor-and-micro-models-85. Also note that you can go to most any Target store and buy an off-the-shelf IR-controlled helicopter that measures 6" long at 10 grams and costs around $35. Ten years ago, AeroVironments was building a disk-shaped Micro Aerial Vehicle (MAV) with a 6" wingspan and was semi-autonomous, had GPS and video and employed a nearly silent direct-drive electric motor.

BTM

See here. It's significantly harder than it seems, kudos to this guy for being able to "fly" it in a stable manner. The thing with the patent is shameful though.

    I have been Flying R/C airplanes and Heli's for over a decade and we have been using technology like this before I was around as others have posted but here is a link to a Ready To Fly (RTF) Trainer plane with AutoPilot Stabilizes in all three axis. Color video transmitters are readily available for cheap, even real time telemetry and GPS modules, depending on how much you want to spend you increase the quality and reduce the physical size and stealth capability (eg. electric vs. combution powered).

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=L XEXK2**&P=ML
RTF Flight stabilise system (autopilot) >$350

http://www.planetalk.com/videoacc.html
Video Systems

http://www.jcsportfliers.org/
NJ based model club w/ links and photos of hobby

http://www.rcuniverse.com/forum/tt.asp?forumid=81
Hobby - Aerial video forum w/ video links

http://www.rcgroups.com/uav-unmanned-aerial-vehicl es-238/
Link to Hobby related "modeler-built" UAV forum

The model airplane guys are on the bleeding edge of battery tech.

Check 'em out,

http://www.rcgroups.com/batteries-and-chargers-129 /

Originally they said it would be very faint. It wasn't until 7 days after the prime observing time that the news managed to cut through the iPhone noise, but by then it was too late.

It was invisible to the naked eye on Saturday. Only after greatly amplifying the frames in software did the comet emerge. It probably won't be visible after Sunday.

Threw some photos of the comet on http://www.rcgroups.com/forums/member.php?u=115141

and made a movie of it right until it was 50 pixels above the horizon. The movie may get uploaded if there's any interest.

There have been reports of lithium polymer batteries spontaneously igniting after being damaged, while being charged incorrectly, after being shorted, and for a variety of unexplained reasons.

See this thread entitled "Data - Complete Guide to Lithium Polymer Batteries and LiPo Failure Reports": http://www.rcgroups.com/forums/showthread.php?t=20 9187

As my name implies I fly R/C aircraft as a hobby. Within the last few years electric powered models have really taken off. Most of this is due to the Li-Po battery. Lithium Polymer batteries are a subset of Lithium Ion batteries but the design of the cells are different.

Li-Po batteries are small and light and can produce a higher continue current than lithium ion. They are very powerful batteries.

One of the problems though...and why I generally stay away from them is that they explode. They can easily become unstable if dropped (or crashed). I don't claim to be an expert but the cells in a lithium ion battery are metal - they can sustain an impact and vibration where as the cells in a lithium polymer are mostly plastic which can cause a mix of the chemicals inside and cause the battery to heat up until it vents and then explodes.

Fire caused by overcharging

Video of a lipo battery going bad.

Li-Poly batteries have been around awhile. Hobbyists were the first I know to use them. I don't know that they have improved in safety issues over the last few years, but perhaps you should see the following
example of a li-poly flame out before buying li-poly batteries?

http://www.rcgroups.com/forums/showthread.php?t=15 1687

Lithium Ion and Lithium Polymer are very closely related. I think the only major difference is the packaging.

From my model airplane experience, LiPo has been a pretty dangerous battery when used improperly. Here is 1 2 3 video's of small Lipo's (3 cells is the biggest) exploding.

As you can see from the videos, just a small lipo cell can create a big 6 foot fireball. LiPo explosions are like a chain reaction, if one cell blows, you can almost bet that any ajacent cells will explode as well.

Over at there is 100's of reported incedents of leaving LiPo's to charge, and the owner returns to find their kitchen/car/garage engulfed in flames. An improperly charging Telsa LithIon pack could probably blow the roof off your house.

3 cell Lithium Battery in a model aircraft 500 feet over my head is fine, but I wouldn't want to park a huge pack like what's in the Telsa anywhere near my house.

"is squishing a lithium ion battery enough to make it catch fire?"

If the battery is Lithium Polymer, it's rather easy to get it to catch fire, as many modelers know.
Overcharge it. Overdischarge it and then attempt a normal charge. Short it, even for a surprisingly short time. Puncture it. Squeeze or hit it enough that it balloons, then ignore the fact and use and charge it as normal.

LiPos are dangerous. There's a reason why it is generally acknowledged that their ideal charging place is a concrete block with a hole in it, or just on lots of sand (with a bucket containing more sand close at hand).

I can easily imagine boxes containing LiPo cells (and possibly other, sharp items) being bumped around while boarding the plane...

Read up.

Yes, but "below 50% charge" actually means "85% of the maximum voltage." For Lithium-Polimer batteries, the maximum voltage is 4.2V and 3.0V is "completely discharged" (in fact dropping lower than 3.0V runs the risk of permanently damaging the battery and causing "vent with flames" the next time you charge it.) 3.8V is considered the ideal storage voltage in R/C circles.

R/C circles probably have the largest percentage of failed Lithium Polymer batteries, because they are discharged at pretty high rates, and the protective circuits on most consumer lithium batteries are removed. Most failures are caused by the following:

  - Overcharging due to the use of a bad charger or using the wrong settings on a Lithium-Polymer-capable charger.
  - One cell of a multicell pack overcharging due to being at a higher initial voltage than the other cells in the pack. This is being mitigated with the use of "balancers" which connect to each cell and maintain equal voltages across the pack.
  - Physical damage due to crashes.
  - Shorting out the battery.
  - Allowing the voltage of a cell to drop below 3.0V.

Many of these have been ameliorated due to technological improvements in the last two years - for example the aircraft-side electronics now cut off the motor at a point where the battery voltage is still safe, chargers have been much improved, and battery packs now come with special connections to allow checking and adjusting voltages on a cell-by-cell basis.

R/C enthusiasts tend to treat Lithium-Polymer batteries with quite a bit of respect as far as storage and charging is concerned. Many will set up a cinderblock on a concrete floor, place the battery in one of the holes of the cinderblock (the holes in the block are set vertically) and cover the top of the hole with a plastic bag full of sand. In case of a "vent with flame", the heat will melt the plastic allowing the sand to cover the battery and put out the fire. Compared to a couple of years ago, however, the incidence of Lithium-Polymer fires has greatly decreased even as use of Lithium-Polymer batteries has increased.

This forum thread has a lot of information about dangers and safe handling guidelines for Lithium-Polymer batteries.

Li-Poly batteries are used a lot in RC aircraft. Here is a link to a page about LiPo fires (with a link to some videos) Lipo Fire info.

Lipos are used a lot in RC flying, but you have to be very careful with them. If they short, they will start to buldge a bit, and can catch fire. Also, LiPos can only be discharged so far, until they are useless (I believe under the 3.7 volt level). If you are interested about rechargable batteries, RC people are the ones to look at. (that includes NIMH, NICD, and LIPO)

Electric RC flyers have been dealing with this issue for a while.

Here is an informational thread about lipo batteries:

http://www.rcgroups.com/forums/showthread.php?t=20 9187

Great aerial photography forum on the 'net at http://www.rcgroups.com/forums/forumdisplay.php?f= 128. I bet they have just about all the hacks required to get cheap digital cameras to work on model airplanes.

(ignore immediately previous post, extraneous < ruined it.)

For maximum efficient endurance I am not sure if I would go with gas or glow engines or electric motors. Definitely not turbines. The advances in lithium polymer batteries recently have made ultra high endurance electric sailplanes a reality. Hour+ flight times at 30+mph on a plane with a 4-6' wingspan that costs under $200.

As to cameras, youll find that with a proper mount there is no need to shut down the engine except for the most high res of shots. Details on hobbyist aerial photography here.

Exactly how is the LiPo battery charged ?

Without a proper charger, combining the energy density of a 80Wh battery with highly reactive Lithium is a recipe for disaster.

http://www.rcgroups.com/forums/showthread.php?t=20 9187

The mind abounds with disturbing images of people abusing batteries in all sorts of different ways..

Common forms of abuse (not specific to LiPo cells, however) :

leaving a battery in a hot car, especially in the sun.

discharging a battery completely in 4 minutes, like many R/C car and plane guys do. The battery generally tolerates it, but it won't last long.

charging a battery at 4C (full charge in 15 minutes.) (Some batteries can tolerate higher charge rates, some can't.)

overcharging a battery (like leaving it on a charger for days at a time. LiPo chargers MUST have circuitry to prevent this, as LiPo cells can explode if overcharged, but NiMH and NiCd cells tolerate it, even though it's still abuse.)

discharging a battery too much (for a NiCd/NiMH cell, you reverse-charge a cell or two, which is bad, and for LiPo/Pb, discharging too much ruins the cell.)

dropping the battery onto a concrete floor. Yes, physical abuse is still abuse.

People deliberately overcharging a LiPo pack and filming it to see what happens.

There's a lot more, but this should give you an idea.

We're not the only ones wondering if this is such a wonderful idea.

We're not the only ones wondering if this is such a wonderful idea.

.
Why does his "the best cameras" aka "pick of the litter" page have 10 (ten) cameras listed for each of the 12 categories? He says the "cameras are not listed in order of preference":

http://www.steves-digicams.com/best_cameras.html

I can see 2-4 choices per, but 10?

Digital camera reviews are no where near as technical and detailed as they need to be to be useful, compare this:

http://www.steves-digicams.com/2003_reviews/exs3_s amples.html

with this:

http://www.rcgroups.com/forums/attachment.php?atta chmentid=118010&stc=1
http://www.rcgroups.com/forums/showthread.php?t=13 1193&page=7&pp=15
http://www.rcgroups.com/forums/attachment.php?atta chmentid=180976&stc=1
http://www.rcgroups.com/forums/attachment.php?atta chmentid=221673&stc=1

Note the "pre-printed form letter" the one guy gets back from his warranty servicing with the check mark beside the following paragraph:

"Your camera is operating according to factory specification in all modes. The phenomenon you have experienced (an orange halo visible in the bckground after taking some pictures) is not a defect in operation of your camera. It is a function of the geometry of the lens optics. Under certain lighting conditions this effect may be noticeable. Darker backgrounds will minimize or eliminate this effect."

You can no longer find the S3 or anything like it on the market, Casio has probably quietly removed it due to huge numbers of returns and warranty servicing costs. You can only find a few on eBay, and ALL are "open return" or "used return, not tested". NONE sold by happy users.

AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review.
.

.
Why does his "the best cameras" aka "pick of the litter" page have 10 (ten) cameras listed for each of the 12 categories? He says the "cameras are not listed in order of preference":

http://www.steves-digicams.com/best_cameras.html

I can see 2-4 choices per, but 10?

Digital camera reviews are no where near as technical and detailed as they need to be to be useful, compare this:

http://www.steves-digicams.com/2003_reviews/exs3_s amples.html

with this:

http://www.rcgroups.com/forums/attachment.php?atta chmentid=118010&stc=1
http://www.rcgroups.com/forums/showthread.php?t=13 1193&page=7&pp=15
http://www.rcgroups.com/forums/attachment.php?atta chmentid=180976&stc=1
http://www.rcgroups.com/forums/attachment.php?atta chmentid=221673&stc=1

Note the "pre-printed form letter" the one guy gets back from his warranty servicing with the check mark beside the following paragraph:

"Your camera is operating according to factory specification in all modes. The phenomenon you have experienced (an orange halo visible in the bckground after taking some pictures) is not a defect in operation of your camera. It is a function of the geometry of the lens optics. Under certain lighting conditions this effect may be noticeable. Darker backgrounds will minimize or eliminate this effect."

You can no longer find the S3 or anything like it on the market, Casio has probably quietly removed it due to huge numbers of returns and warranty servicing costs. You can only find a few on eBay, and ALL are "open return" or "used return, not tested". NONE sold by happy users.

AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review.
.

.
Why does his "the best cameras" aka "pick of the litter" page have 10 (ten) cameras listed for each of the 12 categories? He says the "cameras are not listed in order of preference":

http://www.steves-digicams.com/best_cameras.html

I can see 2-4 choices per, but 10?

Digital camera reviews are no where near as technical and detailed as they need to be to be useful, compare this:

http://www.steves-digicams.com/2003_reviews/exs3_s amples.html

with this:

http://www.rcgroups.com/forums/attachment.php?atta chmentid=118010&stc=1
http://www.rcgroups.com/forums/showthread.php?t=13 1193&page=7&pp=15
http://www.rcgroups.com/forums/attachment.php?atta chmentid=180976&stc=1
http://www.rcgroups.com/forums/attachment.php?atta chmentid=221673&stc=1

Note the "pre-printed form letter" the one guy gets back from his warranty servicing with the check mark beside the following paragraph:

"Your camera is operating according to factory specification in all modes. The phenomenon you have experienced (an orange halo visible in the bckground after taking some pictures) is not a defect in operation of your camera. It is a function of the geometry of the lens optics. Under certain lighting conditions this effect may be noticeable. Darker backgrounds will minimize or eliminate this effect."

You can no longer find the S3 or anything like it on the market, Casio has probably quietly removed it due to huge numbers of returns and warranty servicing costs. You can only find a few on eBay, and ALL are "open return" or "used return, not tested". NONE sold by happy users.

AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review.
.

.
Why does his "the best cameras" aka "pick of the litter" page have 10 (ten) cameras listed for each of the 12 categories? He says the "cameras are not listed in order of preference":

http://www.steves-digicams.com/best_cameras.html

I can see 2-4 choices per, but 10?

Digital camera reviews are no where near as technical and detailed as they need to be to be useful, compare this:

http://www.steves-digicams.com/2003_reviews/exs3_s amples.html

with this:

http://www.rcgroups.com/forums/attachment.php?atta chmentid=118010&stc=1
http://www.rcgroups.com/forums/showthread.php?t=13 1193&page=7&pp=15
http://www.rcgroups.com/forums/attachment.php?atta chmentid=180976&stc=1
http://www.rcgroups.com/forums/attachment.php?atta chmentid=221673&stc=1

Note the "pre-printed form letter" the one guy gets back from his warranty servicing with the check mark beside the following paragraph:

"Your camera is operating according to factory specification in all modes. The phenomenon you have experienced (an orange halo visible in the bckground after taking some pictures) is not a defect in operation of your camera. It is a function of the geometry of the lens optics. Under certain lighting conditions this effect may be noticeable. Darker backgrounds will minimize or eliminate this effect."

You can no longer find the S3 or anything like it on the market, Casio has probably quietly removed it due to huge numbers of returns and warranty servicing costs. You can only find a few on eBay, and ALL are "open return" or "used return, not tested". NONE sold by happy users.

AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review.
.

This is one of my hobbies.

High-lift model aircraft=$30
Electronics for said aircraft=~$100-$300
Cheap 1.3megapixel pocketcam (Aiptek)=~$50
Transmitter=~$100
Total=~$280-$480

Here is a site dedicated to radio controled aircraft and in particular AP.

http://www.rcgroups.com/forums/forumdisplay.php?f= 128

Nothing beats sending up your aircraft (GWS Slowstick in my example) for about 20 minutes at a time, snapping a few dozen pics, landing, and then transfering the pics to your laptop for instant viewing.

So many different variations on a theme, and some ppl even send up their expensive digitals and there are also video camera options available (Aiptek makes a half-way decent one for $99). You can wire them directly to the rx or simply mount a servo to actuate the shutter. Suprised this hasn't come up--I consider this a major geek hobby. :)

There are several pretty good, really cheap cameras out there that take decent pictures and don't weigh a lot that would work better in this application.

For example, the AIPTek Pencam 1.3 weighs 2.4oz and takes 1.3MP pictures. The imager is CMOS (rather than CCD) and so the pictures are sensitive to the lighting, but they usually come out pretty good. AIPTek also makes several other models that work well. You can buy them at Circuit City and Walmart and if you hit the sales right, you can buy one for $50.

The Mustek Mini 3 is also very light and takes pretty good pictures and can be purchased for less than $100.

A good resource for aerial photography - although aimed at R/C airplane aerial photography - is the aerial photography forum at RCGroups.Com. Check out the thread at the top labelled "Digital Cameras under 5oz for aerial photography".

For triggering, you could rig an R/C servo to the switch, or use some form of PIC circuit to trigger it on a timed basis. Some projects like this are listed here.

There's been increasing regulation in the US in the area of model airplanes as well. The Dept. of Transportation and the FAA issued a notice N8700.25 in Oct. last year that regulated "Unmanned Aerospace Vehicles" (link here). Reading through this document a lot of model airplane hobbyists are becoming increasingly alarmed about goverment regulation of their (my) hobby. The notice specifically states that it does not affect model airplanes but then states that model airplanes are flown at an altitude of less than 400 feet - which, if you have been to any model airplane flying field is about 400 feet less than reality.

If model airplanes that fly above 400 feet (which a high percentage of them) are no longer considered model airplanes, but are now UAV's, then they may fall under new regulations.

There are plenty of threads on the RC websites where hobbyists are trying to figure out what to do to try to limit the impact of new regulations on their hobby. One good example is This one.

With high enough doses, I can see that. But I was wondering if in smaller doses, which may seem to have little to no effect, there actually are non-fatal effects such as the more subtle symptoms I mentioned.

I'm not a doctor, so take this with a grain of salt. But what I'm trying to get at is that your body routes around toxins and foreign particles all the time. As long as these particles are insufficient to interfere with your body's chemical operations, its presence should make no difference. The radiological effects add a new wrinkle, because even in super small quantities, they can potentially cause damage to your body's structure. For example, you only need to inhale 20 milligrams of Pu-238 to guarantee death within one month. Portions less than that simply increase the risk of cancer. It's even possible that 1/10 milligram could cause cancer. It's just not as likely.

Now in the grand scheme of things, a few milligrams of nearly anything is insufficient to impact your body in any serious manner. Materials of that toxicity usually impair something very specific and vulnerable such as the nervous system. Most of the radioisotopes I'm aware of don't fall into this category, but are instead classified as heavy metals. Radioisotopes of non-metallic nature (e.g. Iodine) behave exactly as their non-radioactive counterparts.

That is sad if your high school physics taught that... IIRC, 0.5*mv^2 = kinetic energy, not force.

High school physics have long taught this little gem. It's too bad it's incorrect. Not to mention that many people don't know that it's incorrect. For example, a quick googling comes up with links like this one.

The bright side is that most of today's high schools seem to have switched their physics textbooks to newer and more correct ones. Too bad for those of us before the change. :-(

BTW, one thing I did notice when I learned the correct formula:

Kinetic Energy = (mv2)/2

"Every action has an opposite and equal reaction", therefore

Total Energy in a System = mv2

"As an object approaches the speed of light, its mass grows to infinity", therefore

E=mc2

I was pretty proud of myself for that one. :-)

Or did you mean F=ma and you're referring to the insufficiencies of the Newtonian model? I think that the Newtonian model is only significantly false at near light velocities (and therefore quite useful for many cases), at which point the relativistic mass changes wrt direction. i.e. it becomes more difficult to accelerate in the same direction as its current velocity, but not in orthogonal directions (relativistic mass is directional!).


It's not directional, it's dimensional! You see, Einstein explained that everything in the Universe has a "velocity" of light speed. Now everyone knows that you can go West fastest by travelling due west, and south fastest by going due south. But if you travel in a south-westernly direction, you'll go slower toward each point of reference. Now if we apply this to dimensions, an object at complete rest in our universe is going infinitely fast through time. An object traveling at light speed is a perfect rest through the fourth dimension. And guess what? We can even see this effect!

Let's say for a moment that I have two horizontal panels with a ball bouncing vertically between them. If I move the panels, the the ball will "miss" them completely. And yet, I can perform this experiment on a train and be able to watch the ball bounce straight up and down. If we were to pretend that the train didn't exist, what might an observer on the ground see as the panels and ball passed by him? He'd probably notice that the ball is actually bouncing at a slight angle to "catch" the panels.

Now let's assume that the ball bounces back and forth 10 times a second. Let's put a set of panels on a spaceship traveling at 90% c. Re

Appears HERE .

It seems the plane weighs a bit more than 16 grams...

Oops, silly preview button. That link is a bit longer than it should be, and cut out the word "here". You guys know what I meant =P here it is again.

Turns out there's already been a lengthy discussion of this article in the context of motors for RC aircraft...I hate to slashdot my favorite website, but 's the thread [rcgroups.com] ...Skip to the end if you want to hear all the wonderful reasons it sounds like crap.

Engineers in Belgium and Norway have developed the worlds smallest and lightest autonomous and remotely operated flying robots.

BRUSSELS, Belgium and OSLO, Norway, December 17, 2003. After many years of development in technology, concepts and materials, it has for the first time been possible to build micro flying robots weighing less than 7 grams. Unlike other micro flying robots, these recently unveiled robots operate fully autonomously without any cables to transfer power or control signals. The power comes from onboard batteries and they are operated by infra-red or radio based control devices. The micro flying robots were announced today, on the 100 year anniversary of the first powered flight by the Wright Brothers.

In Brussels, Alexander Van de Rostyne together with leading suppliers of micro robotic components, has developed the Pixelito, a 6.9 grams helicopter-like flying robot with a full 4- axis control similar to larger helicopters. Its two-bladed rotor has a diameter of 148 mm and can be controlled by an infra-red control device that enables the pilot to have full control over it in all the dimensions of space.

In Oslo, Petter Muren in close contact with the same team of component suppliers, has developed the Proxflyer Micron, a 6.9 grams totally silent and aerodynamically stable coaxial rotor flying robot that has a rotor diameter of 128 mm. It is controlled via a 2 channel radio transmitter and an onboard FM radio receiver.

Both the Pixelito and the Proxflyer Micron are battery powered, utilizing onboard state of the art lithium polymer batteries, micro electronics and coreless motors. Space age material technology including carbon fiber and Kevlar is used in the rotors and in the mechanical structures. Both robots rely on new and patented, but totally different ideas to radically simplify the necessary control mechanisms. They are built, and unveiled to the public as proof of concepts and as a demonstration of what is possible to achieve in this field of technology using current commercially available materials and components.

The robots are believed to be the lightest and the smallest flying robots or helicopters ever built anywhere in the world and they open a whole new area of possible applications, including indoor surveillance using onboard micro video cameras, military operations as well as other applications in the hobby and toy market. According to the engineers behind this latest achievement, it is possible to build even smaller and lighter flying robots with today's technology, and as the development of motors and batteries moves on, the flight time and capabilities of such robots will further increase.

Engineers in Belgium and Norway have developed the worlds smallest and lightest autonomous and remotely operated flying robots.

BRUSSELS, Belgium and OSLO, Norway, December 17, 2003. After many years of development in technology, concepts and materials, it has for the first time been possible to build micro flying robots weighing less than 7 grams. Unlike other micro flying robots, these recently unveiled robots operate fully autonomously without any cables to transfer power or control signals. The power comes from onboard batteries and they are operated by infra-red or radio based control devices. The micro flying robots were announced today, on the 100 year anniversary of the first powered flight by the Wright Brothers.

In Brussels, Alexander Van de Rostyne together with leading suppliers of micro robotic components, has developed the Pixelito, a 6.9 grams helicopter-like flying robot with a full 4- axis control similar to larger helicopters. Its two-bladed rotor has a diameter of 148 mm and can be controlled by an infra-red control device that enables the pilot to have full control over it in all the dimensions of space.

In Oslo, Petter Muren in close contact with the same team of component suppliers, has developed the Proxflyer Micron, a 6.9 grams totally silent and aerodynamically stable coaxial rotor flying robot that has a rotor diameter of 128 mm. It is controlled via a 2 channel radio transmitter and an onboard FM radio receiver.

Both the Pixelito and the Proxflyer Micron are battery powered, utilizing onboard state of the art lithium polymer batteries, micro electronics and coreless motors. Space age material technology including carbon fiber and Kevlar is used in the rotors and in the mechanical structures. Both robots rely on new and patented, but totally different ideas to radically simplify the necessary control mechanisms. They are built, and unveiled to the public as proof of concepts and as a demonstration of what is possible to achieve in this field of technology using current commercially available materials and components.

The robots are believed to be the lightest and the smallest flying robots or helicopters ever built anywhere in the world and they open a whole new area of possible applications, including indoor surveillance using onboard micro video cameras, military operations as well as other applications in the hobby and toy market. According to the engineers behind this latest achievement, it is possible to build even smaller and lighter flying robots with today's technology, and as the development of motors and batteries moves on, the flight time and capabilities of such robots will further increase.

The RCGroups Aerial Photography Forum has plenty of information about doing still photography and wireless video from Radio Control aircraft, including helicopters, powered planes, and gliders. There's plenty of sample in-flight photographs as well. The Aiptek pen cams seem to be favored and are easily modified to be actuated by a spare channel via direct plugin to the model's receiver. Very cool stuff, and you can fly where you want as opposed to being restricted by a string.

The GWS Slow Stick is a very good choice for a beginner plane that is well suited for hauling aloft a little bit of extra weight. Check out the Aerial Photography forum at RC Groups for more info.

While cool, this actually isn't all that amazing, hobbiests have been making micro R/C helicopters for years, and I've seen a few almost that small. Check out EZONE MICRO HELI BOARD for all your micro heli enjoyment. I also have one of these VECTRON FLYING SAUCER Cheap, easy to fly, programmable messages, great for parties! A butload of fun, really!

this one comes close at 120g though. http://rcgroups.com/links/index.php?t=article&cat= 198&id=4144

Expect to have frequent, expensive crashes while learning how to fly. You will do save yourself a huge amount of time if you spend a few hours (or even a few minutes) browsing some RC forums before toy buy. eg, http://www.rcgroups.com/forums/index.php is a good start.

Also, a mini RC helicopter is much harder to fly than a larger, specially designed trainer. Be warned.

The one I have has single Nimh cell, a tiny motor (probably similar to those used in pagers and mobile phones for vibration) a couple of coils and a tiny magnet. In mine there is no proportional control. One of the cool things is that a bunch of people have started using these as the basis of tiny indoor remote controlled planes - in fact I bought mine specifically to rip apart for that purpose. Unfortunately the car itself was so much fun that I haven't had the heart so far to do anything with it ;-)

Anyway, There's a very interesting thread at www.rcgroups.com about converting these things into aeroplanes - definitely worth a look. There are also some guys trying to make them into helicopters, although I think they may need rather more more modification than the planes do...

The one I have has single Nimh cell, a tiny motor (probably similar to those used in pagers and mobile phones for vibration) a couple of coils and a tiny magnet. In mine there is no proportional control. One of the cool things is that a bunch of people have started using these as the basis of tiny indoor remote controlled planes - in fact I bought mine specifically to rip apart for that purpose. Unfortunately the car itself was so much fun that I haven't had the heart so far to do anything with it ;-)

Anyway, There's a very interesting thread at www.rcgroups.com about converting these things into aeroplanes - definitely worth a look. There are also some guys trying to make them into helicopters, although I think they may need rather more more modification than the planes do...

One thing to note is that using a Pencam on a gas-powered plane (or helicopter) pretty much doesn't work due to motor vibration. You need an electric with the ability to turn off the motor, or a glider.

To trigger the shutter, I used a heat glue gun to glue a servo to the top of the camera and adjusted the throw so that max rudder triggers the shutter.

This is probably the least elegant approach and there are people who have done a wide variety of improvements over this. One of the best is an electronic circuit that triggers the shutter when the throttle is off - which thus works with 3-channel radios, and doesn't require a servo. Since the camera takes pretty lousy pictures with the engine on this works pretty well. There are others - some people have made circuits that use something like a 555 timer to take pictures at fixed intervals, some have made fully electronic systems that allow you to change the camera mode (from stills to movies, etc.).

The best resource that I have found is this Aerial Photography Forum at E-Zone