Gyros and servos for stability.
 

Has anyone here ever used a Micro Gyro and Servos to stabilize their rocket? I have very lite weight micro servos and gyro's that might work to stabilize a touchy rocket and add very little weight.

Yep! Dan Coon down at Huntsville used helicopter gyros and r/c servos to thrust vector a complex water rocket. It had 9 two liter bottles and pvc piping and he flew a Polaroid camera on top. It was great for school demos where he'd give them the photos taken.



George Gassaway built a rocket called the Sun Seeker which used servos and a seeker head using light senors. George's SunSeeker Page

Very cool Zep thanks for the pics.
2 micro piezo gyro's and HS-55 servos would work great for rockets with a micro reciever and a LiPo battery pack. You could inginite the engine remotely from a PCM transmitter and even control the rockets flight path yourself. Please someone stop me, I think I need an intervention. ;)

Well, if you control the rocket yourself, the BATFE might show up at your house. They already hate us because of the NAR/TRA lawsuit. For a while after 9/11, we thought we were going to lose R/C as a hobby.

I doubt the BATF is worried about a D sized flying foam box, but if they want to come over they can race on my Slot Car track. My boys will kick their butts. :D

with a slow moving rocket that might work fine but , the biggest problem to most who have experimented with gyro-stability has been the speed at wich a gyro,servo,linkage system will react. it has to be lightening fast to truely be accurately "steerable".

but for general stability it can work on a relativly slow rocket

Someone will surely correct me if I am wrong about this, but I think that when you start talking about building rockets whose trajectory can be changed while under thrust by either a controller on the ground or by on-board electronics, you are no longer talking about constructing an amateur "HOBBY ROCKET", but instead are talking about fabricating a "MISSILE." I think that "missiles" are, at the very least, covered under a different set or subset of FAA regulations. But I would also bet that building or launching a ground-guided or internally-guided missile would almost certainly earn you quite a bit of scrutiny from BATFE and DHS because of the obvious security issues (your project goes from being an amateur hobby device to being a potential warhead delivery system, i.e., a weapon). Aren't operators of R/C boost gliders required to have their radios disabled during the boost phase of the launch of their gliders for this very reason? IOW, they are not permitted to take control of their gliders until after the gliders have separated from the booster rocket?

One of the fundamental pillars that permitted widespread legalization of our hobby was the principle that our rocket craft are UNGUIDED. I am confident that flying a guided rocket must also surely violate the Safety Code.

I wasn't active in the hobby at the time, but I would guess that George Gassaway's Sun Seeker was most likely seen as an exception that was allowed because it differed in certain key details from the definition of a guided missile, namely, that its active guidance system was limited to correcting the rocket's boost trajectory to assure that it had a stable, vertical flight in the same way that passive guidance mechanisms (like fins) do, and that it contained no devices that could enable the rocket to be steered toward a target while under thrust.

Sven Knudsen reprints an r.m.r FAQ on guidance and control systems at his Ninfinger web site:

http://www.ninfinger.org/~sven/rockets/gcsfaq.html

Mark

You wouldn't need to go to all that trouble. There are several commercial sources for "air start" avionics that ignite auxiliary motors after the rocket has achieved first motion. PicoAlt is one such source; another is Xavien.

http://www.picoalt.com/

http://www.xavien.com/

Mark

Yes, but if he wants active flight control, he still needs the R/C gear. There's no reason to double up on different avionics packages unless you want to get into the "for R/C use only" argument for TX/RX gear. PCM stuff is pretty glitch free...just as glitch free as the old Pratt Hobbies R/C deployment gear that everybody loved a decade ago.

Not at all. A missile is a rocket aimed at a specific target. No one's talking about using a rocket as a missle (guided or not).

There's nothing in the safety codes, FAA regulations, or NFPA that against using active guidance in a model or high-power rocket.

-- Roger