Each year in my Physics class, we end our study of mechanics using model rockets where students collect rocket thrust data from Estes engines and model how the rocket will fly using a spreadsheet and all the 2nd law and motion equations. But now that we have become more experienced in the ways of robotics, several students on our team (also in my physics class) wonder about placing a control system inside a rocket and having it autonomously control some fins with servos and such. Obviously I’m hesitant to strap an expensive IFI system and sensors to a rocket that may come crashing to earth, but it would be interesting to see if a PIC, gyro, and accelerometer could be combined to accomplish a crude but effective guidance system.
Aside from obviously being a very tough challenge, has anyone else considered this and do you know of any regulatory challenges in doing such a project?
I am HPR Level 1 certified to fly up through H and I motors, but I don’t see any where in NAR regulations that forbid an active guidance system.
I was into High power rocketry before 9/11. What you are thinking of has been done. However, if I remember the control system was analog. Remember in rocketry events happen in a much more compressed time frame. There is allot you can do with rocketry that doesn’t involve active stabilization or guidance. You live in the post 9/11 world. In the eyes of the gov you would be considered a possible terrorist. If you want to pursue electronics and rocketry, i would suggest work on building your own altimeter. Start with a simple barometric unit - pop at the top. Then work on accelerometers and data logging. For advanced topic look into Kalman filters to deploy at apogee. Or work on a wireless hybrid fill and launch system. While rocketry was fun, I was literally burning money to play. With First robotics I’m playing on someone else’s dime.
As long as proper clearance is attained and your field is sufficiently large, you shouldn’t have a problem, and as you know, there are many events open to NAR members that already have clearance. As you said, there is nothing in the NAR code that prohibits it, although there are restrictions on unproven designs that you should read, and you may have trouble clearing the rocket with the RSO at your launch event.
You might want to check out this page, which is the only one I’ve come across that covers active guidance.
I would strongly discourage pursuing active guidance. Their have been incidences where the gov have come down on individuals. You don’t want to have to defend yourself. You may win legally but will certainly loose financially. Rocketry is regulated by the FAA and BATF. Any one looking to pursue rocketry at any level should join a Tripoli or NAR club. There are allot of electronic rocketry projects that are just as challenging and involve less risk. There is allot of research that could be done in the area of non pyrotechnic deployment and hybrid engines. The major problem now with hobby rocketry is the BATF regulation. It’s ashame the hobby is being squashed by the BATF. My son is in his first year of engineering with the goal of getting into the aerospace field. The amount of knowledge he gained from hobby rocketry is immense.
For a summer job I teach model rocketry at a summer camp, obviously after 8 weeks it has gotten old so to keep it interesting for me and the campers we try different things, because of the nature of rocket engines they produce alot of trust and move at high speeds (exactly what makes them interesting) the problem that this creates is a small change in the aero dynamics quickly becomes an extreme change in direction, this makes crashing nearly inevitable (any one with model rocket experience will tell you the flight seldomn goes the way you expect it to.). As much fun as a radio controlled rocket sounds it also sounds impractical (not impossible) if you want to try it look into basic stamps and light weight servos. Something I have found the kids like and is more fun is remote controlled air craft we built a couple of these one summer with the intent to race after a dissappointing finish in the first race a friend and I put rocket engines with a modified ignition system on ours and won (although we overshot the target by 500ft) If you try this make sure the nose is pointing up at ignition. My advice is find a long stech of private land to use any thing used on public land must be approved usually by a fire marshall. Good luck.
JamesBrown, I just had that thought the other day, to start with electronics and guidance from an RC airplane perspective first, then attach a few rocket motors on if we feel lucky. This is a long way off, not a project that is starting soon at all. I’ll be doing my Cert for HPR Level 2 next summer and begin to experiment with Hybrid engines. Unfortunately, like in robotics, it’s an hobby that can get expensive quickly.
Up here in Alaska there was some kid a few years ago who thought it would be cool to build a guided missile. His dad thought so too (now your expecting me to say that Donald Rumsfeld showed up at his door in person) so his dad paid for it, and this kid built some guided missiles to shoot down remote control planes. And no one had any problem with it at all, because he didnt try to hide it or anything, he just did it, was successful (the local paper thought correctly that he was some kind of genius) and became a bit of a legend. Please note that im doing this story for memory so im kinda vague on the details.
As for doing the project I would say have at it. Probably the easiest thing you could do would be to track the rocket from the ground and collect data on its flight path and such. You could either put a beacon on the rocket, or use a camera. If you want to actually control the rocket whatever you do dont put FIRST stuff on it. FIRST stuff is ok as far as use in a competition where it is necessary for the officials to have an incredible amount of control over the machine, but it is bulky, slow, and because of its requirement for a radio link it isnt really what you want, in addition to being way too expensive. Get a few PIC micros, a programmer, and have at it. Total cost= less than a quarter of a FIRST control system, assuming you have to buy a compiler and a programmer. If you want to save money and have more fun make them learn assembly :).
Yes, I agree with russell. I personally think if the government has a problem with it then they will find you and notify you. Maybe if you lucky you might make a rocket that is not detectable by radar and the government will want to buy it off of you for Spy purposes. Whatever you do never do that becasue they are hiding things from us. LOL. If they were to find out and wanted to but you technology and ideas it would and could only be benifit towards yourself. And then you might benifit financially.
If you fly a rocket that weighs more than 19oz you need to notify the FAA at least 24 hours in advance to issue a Notice to Airmen (NOTAM) advising them of the flight. I had an Aerotech G-Force rocket that was over the limit which was flown with G motors on private land and had to go through the process. They sent me the vortec information and maps with instructions on who to call and what to say.
As for the story, I have serious doubts that this is true. Even if it were true, it is extremely dangerous both to people and property to attempt something like that. Look into rocket powered gliders.