Quote:
Originally Posted by M. Mellott
remember, F=ma, and if you can't have mass, go with speed
|
Just what I was thinking.
I also like sanddrag's idea, springs to drive it (high 'a'), motor to pull it back (can be slower).
Maybe electromagnetics? (Think solenoid, but longer). A relatively light 'hammer' of magnetized steel, passing through two coils axial with each other -= first one accelerates it a bit, second one the rest of the way, all in a short time. Use capacitors to store the impulse energy. The first coil can also be sued to bring the plunger back.
The idea is that you switch off the coil just as the driving force starts to fall off (center of plunger hits center of coil), then switch on the second one (and off again at the right moment). Problems will be switching a very inductive load on and off fast, getitng the timing right, and heat management. (Force is proportional to the current in amperes times the turns of wire. High current implies thick wire, but thick wire implies fewer turns).
Hope this whets the imagination.
Don