need help building a one-piece jumper

[iwilliwill]

im constructing a jumper (entire device must jump + lands as one piece) that can only be powered by springs and/or elastics..

it has to jump straight up and land with in a 1m x 1m box...

so it's basically gravity + air resistence VS spring/elastic forces.

Also, it has to be released by one person at least 1m away (ex: release with a string)

the goal is to jump as high as possible

 

I am not sure what is the best shape, mass, and material of the jumper

I am thinking of making it a rocket shape from a pen..and wrapped it with aluminum foil (because it's more smooth than plastic?!)

I think the frontal area should be as small as possible, but should it be slightly rounded or pointy?

I am also not sure about how the spring can be conneted and how to release the jumper

[m4rc]

Why don't you use the spring from the pen? You can use a retractible pen (the type with a spring in them. All you need to do is push it down compressing the spring, then let go, and it will jump. If you want it to jump higher all you have to do is replace the spring with a stronger spring.

 

Another option is to do something like the Mario toy shown in http://www.nintendoland.com/funfacts/merchs/mcmario.htm .

[YT2095]

are you allowed Launch apparatus?

I only wondered because what`s to stop the "string" from pulling the entire assembly over and into your face

[iwilliwill]

Why don't you use the spring from the pen? You can use a retractible pen (the type with a spring in them. All you need to do is push it down compressing the spring' date=' then let go, and it will jump. If you want it to jump higher all you have to do is replace the spring with a stronger spring.

 

Another option is to do something like the Mario toy shown in http://www.nintendoland.com/funfacts/merchs/mcmario.htm .[/quote']

 

I am using a spring from the pen..my biggest challenge right now is

1) to make the jumper lock in place in the beggining, becuase one of the criteria is being able to lock the system in place for an infinite amount of time

2) release it straight up by ONE person at least 1m away using things like a string

[iwilliwill]

are you allowed Launch apparatus?

I only wondered because what`s to stop the "string" from pulling the entire assembly over and into your face

 

no... the teacher emphasized that the thing must be a jumper not a launcher

I think there should be some kind of holder where when you pull the string it will be stuck there (the spring being compressed at the same time), and when you release, the thing will jump, but if the string can only be pulled by one person..wouldn't that be not balanced..then the jumper can't jump straight up..

[YT2095]

I`m thinking along the lines of a spring inside a tube with a lid and a small hoop and pin keeping this spring inside in a conpressed state, like a Jack-in-the-box mechanism, the string goes onto the pin, the pin goes through the hoop that keeps the lid shut.

[iwilliwill]

I`m thinking along the lines of a spring inside a tube with a lid and a small hoop and pin keeping this spring inside in a conpressed state, like a Jack-in-the-box mechanism, the string goes onto the pin, the pin goes through the hoop that keeps the lid shut.

 

ok..I'm sorry..but I have trouble visualizing this..can in explain more clearly.

Thanks!!!!!

[YT2095]

imagine a box with a hinged lid.

imagine the side that opens this box has a loop in the side of where the lid closes onto ( a metal loop with a screw end like those used in net curtains).

but how does the lid close if there`s a loop stopping it? well there`s a small hole in the lid that allows the loop to pass through it.

 

of course if you were to close this lid and then put a lock through this loop then you`de never be able to open it!

so we won`t put a lock thtough the loop, we`ll put a chopstick through it instead! so while the chopstick is in there, the box can`t open, but pull the chopstick out and it will

 

now then, you get a big spring and shove that into the box and close the lid on it, then put the chopstick through that loop, the box is closed and safe now, but when you pull the chopstick out, the lid flies open and the spring jumps out!

 

well, from there all you really need to do is tie some string to the end of the chopstick and you can pull it out the loop from a distance

[iwilliwill]

but in order to mee all the criteria..the box has to fly too..as well as the chopstick..