Algodoo

Very nice. How do you measure efficiency? When calculating (total energy gained by projectile at release)/(total energy lost by trebuchet), I get 77%. It appears that the trebuchet is 97% efficient at release and then looses another 20% settling down after the throw.

Thnaks! I divided projectile kinetic energy by potential energy lost by counterweight, but total energy lost by system seems to be a better measure.

I'm still trying to build supersonic treb with reasonable masses and dimensions, but enormous amouts of energy are lost in last arm unless it's very light.