Sunday, June 28, 2009

Toypedo update

Well, since my last Toypedo update, I formed two paper mache shells and am building a rocket from them. It is going to be ugly with a capital UGLY. I may or may not reveal its ugliness.

Although they are the way to go, I'm not going to be building a fiberglass version any time soon. If I need fiberglass for some other reason I'm buy enough to try again. For now, meh. I hope the latex mold doesn't deteriorate too fast.

I mentioned before that RockSim showed the basic Toypedo to be very unstable ('off the chart'). I think very unrealistically so, but was planning larger fins anyway. Ken from ZZakk's Lab suggested adding a ring tail. I did so and that works out great. I attached an image from the sim below. Please note two things. First, the CG is not intended to be anywhere near accurate at this point. Also, adding a ring tail requires that you add standoffs to the body...which RockSim includes in its results. If you add fins on top of another, the program will use both to compute stability, so this model's GP is a bit optimistic. I removed the V2-like fins and the CG barely moved so, again, this is close enough for now.