IronGoober wrote on Oct 6
th, 2020 at 2:27am:
This was more work than I thought it would be. Kudos to Sarosh for all of his video analysis.
Thanks! Nice job with solving the problem of the view angle, I had trouble since my slinging style is slanted or sidearm and I cant get a camera over me .
IronGoober wrote on Oct 6
th, 2020 at 2:27am:
Because of the large effective radius, the angular error is much smaller which makes it easier for the human brain to calculate the release point. That is the thought anyway. I didn't prove that yet, but I'm heading in that direction.
since the path is not a circle that is the proof that every point on the projectile path has it's own curvature (in other words the curvature isn't a constant) and by having a lower curvature (bigger radius) for the same velocity(=dx/dt ) your dθ/dt is smaller dx=R*dθ => dθ=dx/R (bigger R gives smaller dθ where R has to do with the path and not the sling length)
It's not if but what style/technique/equipment makes the curvature smaller.
wanderer wrote on Oct 6
th, 2020 at 6:59am:
You need to be moving the hand to accelerate the sling, but in doing so you tend to increase the radius of curvature of the path of the sling projectile and thus reduce the tension in the sling (given by mv2 /r), where r is the radius of curvature of the path at that point and NOT the length of the sling.
by length of the sling you mean stretch or the length?
I've been thinking how much energy is absorbed/lost by stretching in the cords or if the smoothness felt by using stretchy cords adds any benefit.
the lag angle with that cos(theta) explains very nicely why you shouldnt struggle before releasing that is when theta is close to 90° => power transfer is 0.
wanderer wrote on Oct 6
th, 2020 at 3:27am:
Interestingly, I think there is a contrast with trebuchets here, where you generally want to slow the arm down close to the launch point - in order not to have a madly swinging arm left after the launch. That condition doesn't have to apply so much with a manual sling.
I dont know about this, I think it would be pretty awesome if the arm stopped by itself . with heavy stones it'll be easier but when going for speed there is going to be wasted energy.