Ball Firing Canon

[shaiqbashir]

Hi guys!

well! i want to make a canon that should be able to fire tennis balls upto some height. lets say upto 80 cm above the ground.

it should form a projectile of the ball.

I want to use it in a robot, i just want ideas on how this cannon can be made!

thanks in advance!

good bye!

 

[ante1]

Hi shaiq,

You can use compressed air, carbon monoxide, or perhaps a small amount of propane (cigarette lighter gas) and an igniter.
Or, you could go mechanical and do it like we discussed in an earlier thread.

 

[shaiqbashir]

well! thanks for the help ante!

i want to go for the mechanical side only. now in the earlier thread, i remeber that i asked you about an idea of displacing the ball in the tube one by one. BUt this time, i want to fire them to a certain height above the canon in the form of a projectile. Just like a canon fires a shell and it forms a projectile before hitting the target. So, i want to make a firing canon, that can fire a tennis ball to a certain height, What should be the suitable mechanism for that. SHould i use plungers??? but plungers of this much power, i think are difficult to find isnt it..??

what should be the alternatives.

or should i go for a robotic crane or a robotic arm??

i shall be thankful to u for ur earlier reply!

Take carez!

good Bye

 

[ante1]

Ok, if you must go purely mechanic you must use some power which is equivalent to the work that’s needed to be done. A solenoid (plunger) needs power and I don’t know how much since I don’t have the formula clear. Are you in shortage of power to spend in this project? I suggested the propane / igniter variant since this will consume very little power from the project. I don’t think a robotic arm or similar would be an option here.

 

[Theatronics]

Remember that a tennis ball in normal use is meant to absorb energy and then return that energy to reverse direction.  You do not need a LONG throw to project the ball. A slug from a solenoid moving very quickly will make impact with the ball and compress it. The compression would be the same as if you had thrown the ball on the floor. After motion stops the fall is flattened out.  The amount of flattening depends on the energy imparted.
Then the ball returns the energy as it pops back into shape and springs from the floor.

Force is speed times mass.  If you weigh the ball and find a plunger that weighs more then the high speed movement of the solenoid will cause the ball to pop from the tube.

80cm should be easy to reach with this type setup, and it will not require a long tube or a complex compressed air system.  You might want to put a large bank of caps onboard and then use a high current relay (Like an automotive starter) to dump the energy into the coil. This will give you much more kick in the coil.

-Mike

 

[Muhammad Abu Bakar]

Aslam O Alaikum Shaiq,

Why not use the centrifugal force of a body rotating in circle. Acutual mechanical may consist of a continuously rotationg arm. Rotating at one end with a hand on the second end. Hand grips the ball till ball's w is sufficiently high and then release the ball. Analogy of the game where a player throws the hammer first by rotating himself in circular motion.

I think this way you'll need lesser force to grip the ball while ready to be released than the case in which you apply a force to push the ball. I mean a plunger type grip.

 

[Theatronics]

Hey,
    We could combine those ideas!
Use a spinning motion to store energy in a weighted bat
And then hit the ball with the bat at the end of the swing.
Still one motion.  Use a notched tube to hold the ball.  The
Notch on the back will guide the bat to the exact point on the
Ball with every hit.  By tilting the tube you can get different
Trajectories.

-Mike

 

[shaiqbashir]

Thanks Mr. Muhammad Abu Bakar and Mr. Theatronics!

both ideas seem to be pretty good and practical. Now, can u guys explain me ur ideas once more with the help of some diagrams, because i think im still having some confusions in clearly understanding ur ideas.

If the centrifigual property is to be utilized, dont u thin that there would be lots of uncertainities in reaching the target, one cm wrong release and the ball will miss the basket. isnt it??

how to make it very accurate.

i beleive that im not getting ur great ideas clearly. Kindly provide some more explaination and diagrams if possible.

I shall be thankful to u for this act of kindness.

Good Bye!

 

[Theatronics]

Here is a rough sketch of the Bat and Ball Idea.
Build the whole thing on a platform. Then tip
The platform to aim.  The notch in the tube holding
The ball will help insure that the bat hits the ball
At the same point each time.

-Mike

View attachment 39580

 

[rybitski]

This past year my team advacnced to globals in Destination Imagination, we also had to launch tennis balls. Our device was capable of launching a tenis ball a distance of 14 feet and at the 14 foot mark the ball was at least 3 feet in the air.
The design was simple, a bench rrinder motor with a wheel attached. The design was similar to that of a pitching machine. I have some detailed photos, but will not upload them tonight... If you are interested in this design let me know and I will post pictures. but in the mean time here are a few: http://rybitski.googlepages.com/dipictures

 

[shaiqbashir]

@rybitski
HI rybitski

thanks for the links!

your idea looks pretty useful no doubt.

please upload the detailed pictures so that i can fully understand what your idea is basicallly.

@Theatronics

Many thanks for that detailed pic theatronics.

sorry but i still have some confusion in this picture, i want to know the plane of rotation of the bat is it rotating horizontally or vertically. And how the tube would be able to hold the ball,  your notch idea is not cleared to me properly. Please please make it cleared!
thanks in advance!

Good Bye!

 

[rybitski]

http://www1.snapfish.com/share/p=203251156568383057/l=122722149/g=30666963/otsc=SYE/otsi=SALB

Here is the link to the album. If it doesn't work let me know.

 

[shaiqbashir]

Thanks a lot Mr. rybitski

 

[rybitski]

I hope that helps.