# Launching a golf ball

1. Feb 19, 2008

### garrett32

we have a physics project and the goal is to make a device that will play a variant of golf. we have to design a device to strike a ball into a hole using as few strokes as possible. there are gonna be three holes we need to "play" with our machine- 1st 40yard straight 2nd a "dog leg" 30 yards each side and the 3rd a 70yard straight away.

i was wondering if anyone had any cool ideas that would allow for a ball to accurately and constantly launched from a movable device

here are the rules:
the launching mechanism must not use more than a minimum of human force,
the device must be able to easily reset after each trial,
you can select a "ball" that u wish to use,
ball must be spherical and not able to move under its own power,(darn)
the device should if at all possible not use any consumable parts if used they must be able to reset quickly,
spending limit no more than \$100,
under no circumstances explosives, incendiary devices, or pressure-based devices of any kind can be used -this stinks:(
all energy put into device must be mechanical or electrical in nature,
must be safe,
device must be able to fit through class room door

thanks

2. Feb 19, 2008

### Tachyonie

Hello, I am not sure if this doesnt belong into HW forum but it sounds fun to me, wish we had these projects.

I had an idea for the most basic device, well actually two, based on mechanical force. I made this little picture which should give you the idea: http://img146.imageshack.us/img146/3817/golfox9.jpg [Broken]

If I assume that you dont have to base it on any calculations all you have to do, is build one of these two devices and take it on the golf field - or the place where are you supposed to show it so you have good idea about the amount of friction and obsticles the ball has to go through. Then apply certian force: for example lift the club by 40 degrees and let it go. Note how long far did it went and then try different angles or you can even try pushing it but then it might be more complicating calculating the force applied.
Work out how much you have to pull/push/lift for every of these lenghts and voila, you get very simple device.

Tachyon.

Last edited by a moderator: May 3, 2017
3. Feb 19, 2008

### Danger

Welcome to PF, Garret.
You could build it like a gun barrel, but with a spring-loaded plunger similar to (but much stronger than) one in a pinball machine. Your range could be dialled in by adjusting the spring tension. Using a Superball (if they still exist) rather than a golf should give you more distance for the amount of force applied.

4. Feb 19, 2008

### garrett32

what kind of spring would you recommend using and where could one buy a strong spring needed to build such a device?

Last edited: Feb 19, 2008
5. Feb 20, 2008

### Danger

Given the range involved, I'd be looking at grabbing a hood spring from a wrecked car. You can probably get it for free, or a couple of bucks at most.

6. Feb 20, 2008

### Tachyonie

One more suggestion

Or if you cannot get spring, you can use weight as additional way to get some extra power into it.
Vis.: http://img136.imageshack.us/img136/6480/golfcopyjl2.jpg [Broken]

- Closer the weight holder is to the end of the club: Adds more power.
- Bigger the angle/higher the club is: Adds more power.
- You can modify the height and direction at which the ball will travel by adjusting the spot where the club hits the ball. So if you put the ball higher from the ground, higher it will fly.

I am sure you know all these things yourself. Advantage of this device is that its very easy to use and there are no springs involved which always complicate the building process. Ofcourse in the end it might be a bit heavier, but more stable and hopefully accurate.

Tachyon.

Last edited by a moderator: May 3, 2017
7. Feb 20, 2008

### Danger

I just re-read your assignment rules and realized something that should have been obvious. As it is worded, Tiger Woods fulfills all criteria--with the probable exception of the cost limit.

8. Feb 20, 2008

### garrett32

thank you guys so much

tachyon- i like your suggestion and nice picture but how would you go about attaching the golf club securely enough so that we could add weights

9. Feb 21, 2008

### Tachyonie

Well I am sure its possible, you dont need to use golf club in the first place, you may chose to use only the end, and you can use welder to attach it... but thats something I cant you with. :) Go to engineering forum or ask your neighbour which spends most of his day in the garage.
Good Luck!

Tachyon.

10. Feb 22, 2008

### garrett32

thanks a lot! i was so worried when this project was assigned and i didnt have a clue of what to do, but now i am confident that i can do it, thanks to your help

11. Mar 4, 2008

### garrett32

We are thinking of building a sling shot but thinking about constructing it in a tube (PVC pipe) to have it more accurate. We were thinking of using a bycicle inner tube for the rubber band part( we thought it would be stronger and be able to launch the ball farther). Do you think this will work?

12. Mar 4, 2008

### Danger

That's pretty much the way that I was thinking with the spring idea. You still need some sort of plunger to follow the ball up the tube, because the elastic band can't. I must admit that something like an inner tube would probably be easier to work with than a heavy spring.