Robotics and Rocketry??

superdog

So I'm new to this forum and robotics in general. Just to give an idea on where I stand, I have finished the book for the boe-bot and have been playing with some of the add-on sensors. While watching the history channel, I saw an old Soviet mobile ICBM launcher. Has anyone ever tried to apply this concept to a boe-bot sized robot using a model rocket? Use the Ping to find a nice, open area outside and launch a model rocket mounted on top? I figure make a sort of blast shield out of a steel sheet, maybe 26ga and mount that on top of the board with some standoffs. Mount the rocket on top of that. Has anyone here done anything similar? Any potential issues you can think of? As with any model rocket, a safety system would be important. Perhaps have the robot get to its launch site and wait for input from maybe an IR emitter? Has anyone ever tried anything like that? I guess it is just the kid in me that wants to see something like that in action.

SRLM

This sounds dangerous. If the robot (autonomous, I assume?) gets to the launch site, starts to tip over, then fires the rocket it could go a long ways. That said, if you wait for human input (aka, yours) then it might be better. The challenge is probably making an autonomous robot to get to the launch site. You could make something fairly simple with an RC car though.

Mike Green

The major problem is safety. I would not trust an automated system like you're proposing without at least a wired interlock that has to be manually activated once the robot reaches a potential launch site. IR is probably not the best thing to use in direct sunlight. You could probably use an RF remote control like those used for garage door openers, but not without the manual interlock. There's too much risk of a false trigger.

superdog

Oh, absolutely. I've been into rocketry for a while and would never do something totally autonomous. Way too much that could go wrong with that. There will always be some kind of manual safety to remove before a rocket will fly. As for the IR thing, it was more or less the first thing that came to mind. RF would without a doubt be better. I figured it might not be the best of ideas in general. That is exactly why I asked those that know much more about robotics than I do. I'm not sure that I will pursue this much further, but I still think it is an incredibly amusing idea to toy with. Thanks for the input! No better welcome to a forum than sound advice!

Ugha

This is an interesting sounding project if you do decide to go through with it.

I'd recommend that you do all your testing with some kind of nerf rocket launcher
or something of the like. That way false triggers aren't a huge deal.

sylvie369

Two issues come to mind:

1 - Black powder exhaust residue is corrosive, and will quickly destroy any exposed circuit boards. When we fly electronic altimeters or staging timers in high power "dual deployment" rockets, we have to seal the bulkheads between the electronics and the deployment charges, in part to avoid overpressures to the pressure sensor, but also to keep BP residue from corroding the electronics. If you're thinking about flying a model rocket from directly atop a BoEBot, you'll need to seal the BoEBot electronics. The blast deflector isn't going to properly keep BP residue from the circuit boards.

2 - A BoEBot by itself is far too small to be a stable launching platform for a model rocket (though it might work for a MicroMaxx!). Remember that when the wind hits the fins of the rocket as its sitting on the pad, it can push and twist with quite a bit of force. I just spent the weekend helping rocketeers at the National Sport Launch load their rockets onto the pads, and even in fairly light winds on Saturday, it took some effort to keep things in place properly. To pull this off, you'd need some kind of extensions coming out the sides, contacting the ground a foot or more from the BoEBot itself.

Finally, I'm not sure what you're hoping to accomplish with this, other than having a mobile launcher. I think it would be mighty difficult to do anything autnomous that was useful. Finding a large enough launch site would be a very difficult task requiring quite a bit of intelligence (heck, most people can't do it - that's why we join our local NAR chapters and fly from their fields). We're not talking about finding a five-foot diameter clearing. For an A motor, the minimum site dimension is 100 feet, and goes to 400 feet by the time you're flying C motors. You'll need a lot more than that if you want to get your rocket back. Finding the right spot on the field (e.g., far enough upwind from the inevitable trees) presents a second problem. And how would it check to make sure that the skies and range were clear (of airplanes and of spectators)? Or even that your Bot hasn't parked itself under a tree or a power line?

Now if all you're hoping to do is to put a rocket on a pad that has wheels and motors on it, and drive it out to the spot from which you're going to launch, here's a device that could easily be modified to do it:

http://www.vexrobotics.com/vex-robotics-vexplorer.shtml

It's discontinued, but there must be quite a few of them out there collecting dust. Put the launch rod and blast deflector out far enough on that arm, and you might even be able to use the video camera to get "pads-eye-view" launch video. There are no exposed circuit boards (though you'd still want to cover up the places where the wires connect), and it's heavy enough to provide a stable pad for A, B, and C motor-propelled rockets. I'm almost tempted to try this myself.

If you do try it, please be careful, and follow the NAR Safety Code as well as the local laws:

http://www.nar.org/NARmrsc.html