Re: OT: Repeatably lobbing "projectiles"

Don Y <blockedofcourse@foo.invalid> wrote:

On 11/21/2024 5:52 PM, bp@www.zefox.net wrote:

Don Y <blockedofcourse@foo.invalid> wrote:

>
Ideally, I would like the mass to STOP at the destination (not bounce
or roll away) but that's a secondary goal.

 
Apologies if I missed it, but what are the masses and accelerations in play?

 
The masses are negotiable.  As is the acceleration (as long as you
can overcome gravity).
 

Per projectile? All the same? Are they fragile? Same aerodynamics,
or variable?  Grams per cc, or cc's per gram?

The goal is to PLACE a "thing" (projectile) at a specific location
relative to the launcher.  And, to have it reach that location
with minimal interaction with anything located between the launcher
and destination.

What's the permissible error in position and landing speed?

 
E.g., If something was located immediately adjacent to the
launcher, the projectile's path should go OVER the obstacle
and not expect to be able to pass THROUGH it.
>

That's a mortar or howitzer.
 

Imagine using a nerf gun to lob those little sponge balls
up, over obstacles -- but, being able to precisely control
the range so they land where planned (no farther nor shorter)

Now you're talking projectiles dominated by aerodynamic drag.
Does your launcher need to take air movement into account?

But, to do so completely under automation, without any human
intervention.

Are you thinking of something like
https://en.wikipedia.org/wiki/Girardoni_air_rifle
?

One could build a version to launch Nerf balls. Note that it
used a hammer to operate the gas valve and compensate at least
partly for pressure changes. You'd want a very low pressure
for 20 feet. Perhaps you want a toned-down potato cannon (I
think that was mentioned previously by someone).

hth,

bob prohaska