The Usage of Microcontrollers in Model Rocketry
Martin_H
Posts: 4,051
My son's Cub-scouts pack has been building and launching model rockets. I recently went to a vendor's websites to buy supplies as they are getting hard to find locally. One thing that struck me is that this is not the same hobby as when I was a kid. There are some seriously big models and impressive electronic payloads and cameras.
Here's an amazing example:
http://www.apogeerockets.com/Altus_Metrum_GPS.asp
That thing is probably better than the computer they used on the Saturn V! Anyway I thought people might be curious about a non-robotics use of a micocontroller.
Here's an amazing example:
http://www.apogeerockets.com/Altus_Metrum_GPS.asp
That thing is probably better than the computer they used on the Saturn V! Anyway I thought people might be curious about a non-robotics use of a micocontroller.
Comments
Attached are a couple of new photos of one of my XBee boards mounted in a 12" diameter scale model of a Navy Jayhawk missile, along with a photo to show you the rocket's size. This rocket was built by a guy in my club, a former Air Force test pilot, and will fly next weekend at Midwest Power 8, the big annual launch in northwestern Illinois. Here's a "build thread" for the project:
http://www.rocketryforum.com/showthread.php?t=9044
Most of us flying high power rockets use some kind of electronic altimeter, usually one much simpler and less expensive than the Altus unit. The use of onboard GPS with a transmitter is becoming reasonably commonplace as well. I've flown one of my own design a couple of times, with moderate success (of course installing an expensive GPS transmitter is the best way to insure that your rocket lands within sight of the launch pad).
Here is a nice thread on these very forums about a school team out in New Hampshire that is flying a fairly elaborate Basic STAMP-based datalogger to almost two miles out in the Black Rock desert:
http://forums.parallax.com/showthread.php?t=122688
sylvie369, that was one impressive build thread.
And I don't think it's nearly as neat as Sylvie's project - we just used a regular model rocket. ;]
But if anyone is interested, my partner and I maintained a blog during the design process to keep local schools updated on our progress. You can see it here: http://seniordesign-rocketgals.blogspot.com.
Cheers,
Jessica
Unfortunately, that rocket was lost in a forest about 3 years ago, but it flew about 35 times first.
In your blog you wrote
What did you mean by "minimal cogs"? And why did rotation acceleration use two cogs? Also, how were you transmitting the data? (I can't see the schematic in google docs.)
I think it sounds considerably more impressive, to be honest.
Big rockets are cool, but electronics take more knowledge and skill (and besides, remember, I didn't build the Jayhawk - it's just one of my little transmitters along for the ride). What Jessica described would be easily the most sophisticated thing to fly at any launch I attend, and I'd _love_ to see more projects like that.
http://green.yahoo.com/blog/guest_bloggers/73/father-and-son-film-outer-space-do-it-yourself-style.html
The issue was that I was using an IMU object from the Object Exchange which was definitely more cog-hungry than needed. But, I was running out of time and had to sacrifice code efficiency to get the rocket off the ground. We had plenty of motors for launch, and figured why wouldn't we want to launch the rocket a couple more times than necessary?
For communication we used the HAC-UM96 Long Range Radios available from Sparkfun which boasted a range of 500m - definitely necessary when wanting to transmit from a rocket. It took awhile to get going with them since the documentation wasn't very clear that Sleep was always enabled, so my project advisor and I spent many hours with an oscilloscope scratching our heads wondering why the devices weren't communicating when just sitting next to one another on the table! But once we jumped that hurdle the devices worked perfectly and we had no troubles receiving data during the entire launch procedure.
@sylvie - "Allons-y!" is a perfect rocket name! I'm a complete Doctor Who fangirl. One of these days I'd really like to finish cleaning up my code and maybe getting into some hobby rocket launches. And I'd like to add GPS so we could more easily locate the rocket. We lost a lot of hours searching through palmettos to retrieve it.
I've been building rockets since I was in elementary school and loved it - it was a class we could take over the summer in "College for Kids" and then I would get another one from Santa! Growing up in Florida allowed us to launch pretty much any day during the year, except when the hurricanes hit.
A friend of mine asked me to do something similar...with a kite. He's still working on the design, constantly asking me for input about electronics and surface controls. In all, I think it's going to be a cool project once I get to start on my side of things.
Fred
Uh-oh. "Allons-y" has something to do with Doctor Who? I had no idea.
I used it because I'm a francophone - it was the title of one of my textbooks.
Surely you don't think that we Wisconsinites stop flying in winter, do you?