The Impossible Project

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The Impossible Project

Timothy Foster 03 Dec 2008 18:52

I am now faced with what has got to be the hardest school project in history. We have 8 days to build a tennis ball launcher that has to launch tennis balls 20 meters away onto a bulls eye with a diameter equal to the tennis ball's diameter. We get three shots. Oh, and we have to write pages of documentation as well. What is the best way to accomplish such a launcher without using explosives, pneumatic systems, pyrotechnics, or pressurized systems?

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Re: The Impossible Project

Socks 03 Dec 2008 21:11

I'd use plastic tubing with some sort of spring linked to a trigger mechanism. Perhaps a lot of rubber bands?

I'd just be glad it isn't golf balls.

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/Socks

Re: The Impossible Project

jnesselr 03 Dec 2008 22:46

This is an example. The tennis ball would go in the pipe.

Last edited on 03 Dec 2008 22:49 by jnesselr Show more

Re: The Impossible Project

School of Ti-84s 04 Dec 2008 01:12

could you use air pressure such as an air cannon??

because i have a really good machin that fires them really far, and the trajectory is almost 3 meters away from each shot…

Re: The Impossible Project

School of Ti-84s 04 Dec 2008 01:12

wiat scrath that

Re: The Impossible Project

School of Ti-84s 04 Dec 2008 01:25

To refer to an image attached to a page, use pagename/filename

thats my idea

it will put much stress on the bungie cords or rubber bands or rope that it will just take a flick of the pin to launch it

good idea i think

Re: The Impossible Project

School of Ti-84s 04 Dec 2008 01:27

To refer to an image attached to a page, use pagename/filename

why won't it work

Re: The Impossible Project

School of Ti-84s 04 Dec 2008 01:31

To refer to an image attached to a page, use pagename/filename
To refer to an image attached to a page, use pagename/filename

Re: The Impossible Project

jnesselr 04 Dec 2008 01:40

It won't work because you are trying to access them off of your hard-drive. I've created this page just for that situation. Just upload your files to that page, click info, record the url link, and use the image thing like you did in your post.

Also, if you have multiple posts, just click options and then edit to edit your posts.

Last edited on 04 Dec 2008 01:46 by jnesselr Show more

Re: The Impossible Project

ownagef8 04 Dec 2008 02:04

i think your'e trying to be super cool and have an awesome project when you really just need to be a "simple thinker"- lol
We’re all familiar with calcs and have to use technology for everything, don’t we?
i just googled it and i guess people have used catapult like things. But i agree- it must be practically impossible. The key to such projects is CONSISTENCY- cheap elastic things could lose stretchiness and so on.
Here's a link-
http://www.physicsforums.com/showthread.php?t=54527

Re: The Impossible Project

Timothy Foster 04 Dec 2008 03:11

So far, I got four different ideas just by reading your posts.
Spring
Motor
Elastic
Catapult
In the past, I built something that launches ping pong balls with 53% accuracy. I found out quickly that catapults don't work (1 out of 36 success, yikes!). My thing used a spring. However, I find a spring hard to come upon that can probably have such magnitude.
A motor is a good idea, but the problem is finding one. It would probably be expensive.
And elastic components are susceptible to temperature which will make the performance vary from practice to actual launch.
See, this is why I said it was hard. So far, I like the motor and spring. The motor can be set to a calculated speed for consistency (a definite need), and a spring is easy to work with (except for this contraption, it might be hard to set up the launch). How can these ideas be made so that a final product is born?

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Re: The Impossible Project

builderboy 04 Dec 2008 04:55

Since accuracy is the prime objective here (distance is easy heheh) then i would suggest a long pipe with something at the bottom to launch it out. The pipe would help ensure that the ball would stay in a consistent path.

As for a launching mechanism, i would recommend a spring at the bottom, or a large band of elastic that stretches down into the pipe from the front that is attached to a platform of some sort bellow the tennis ball. (I'd go for the spring, the only problem is finding one)

Re: The Impossible Project

DarkerLine 04 Dec 2008 05:48

What qualifies as a launcher? I assume that using a tennis racket would be cheating, but what condition disqualifies it?

Re: The Impossible Project

Timothy Foster 04 Dec 2008 13:40

There is no size limit. It cannot be human powered. No explosives. No pressure systems.

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Re: The Impossible Project

architeuthiskid 04 Dec 2008 20:53

Are those the only parameters? If they are, I have an idea that would almost impossible to miss with.

Re: The Impossible Project

Socks 04 Dec 2008 22:58

Tubing. Make it use gravity roll the ball through tubes into the hole.

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/Socks

Re: The Impossible Project

Jonathan Foster 04 Dec 2008 23:42

Wow, that sounds hard! I have an idea. Maybe you could make a motor so that a tube has a section cut from the middle and wheels (top and bottom) are inserted. The top wheel would spin counter clockwise, and the bottom wheel would spin clockwise. The wheel's spacing would have to be adjusted so that when a ball touches the wheels, the ball moves and squeezes in between. When it leaves the wheels, the push and pressure created by the ball moving in between the wheels would launch the ball.
EDIT:All I'm doing is explaining graphmastur's idea.

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http://origami.wikidot.com/
:)

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Last edited on 04 Dec 2008 23:51 by Socks Show more

Re: The Impossible Project

jnesselr 04 Dec 2008 23:56

I knew that example sounded familiar.

Can I join your site?

Re: The Impossible Project

Timothy Foster 05 Dec 2008 01:37

To describe a picture, you must do it in "1000 words". You should have seen what happened when James Kanjo challenged me to describe a white picture with a singular black pixel in the middle. I got to 231 words, which all described the black pixel, and stopped because I was bored. I hadn't even started talking about the white pixels around the black one.

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me

Re: The Impossible Project

Jonathan Foster 05 Dec 2008 00:07

Sure! I'll let anyone join my website! Tim just joined. My website isn't developed much yet, but with some help, it should get going.

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http://origami.wikidot.com/
:)

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Last edited on 05 Dec 2008 01:33 by Timothy Foster Show more

Re: The Impossible Project

Timothy Foster 11 Dec 2008 23:34

I petitioned the teacher for a better due date, and it worked.

So, the solution? What our group came up with was a strange doohickey with a metal beer chick whatever-it-is on the end. We fit a PVC attachment on one end with a long tubular shaft. The shaft has a wooden dowel coming through it. Bungee cords are attached to the beer chick am down to the dowel. So, when the dowel is pulled, the bungees make it go back up the shaft to hit the ball resting in the beer chick.

Thanks for your support!

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Timothy Foster - @tfAuroratide
Auroratide.com - Go here if you're nerdy like me