how do i build an egg launcher?

[student2007]

ok, i need to build some type of mechanism to launch and egg into a pool of water ( approximately 1meter in diameter ) for my physics class.

 

we need to be able to launch the egg at least 15 meters. the pool will be set anywhere from 5 to 30 meters away ( this assignment seems to be more about being able to adjust the launcher ). egg must survive.

 

the egg may be set in a container of some sort but the whole thing we are launching must not weight more then 400grams.

 

problem comes in because my teacher is a nerd, he wants us to have some sort of a launching sequence. he says we need to be able to press one button to get the launcher ready to launch ( start a countdown as he says ) and another to trigger the launch.

 

also, before u press the first button, the launcher must rest freely and have no potential energy ( springs must not be compressed ).

 

i can think of numerous ways to do this but i cant think of a "launching sequence" that im sure will work.

 

i would appreciate any insight on this and will be checking back on this thread regularly

[Klaynos]

a mass held above a drop, first button drops the mass which winds some potential energy holding thing, second button releases.

 

I can think of a couple tricks to keeping the mass of the thing down, mainly by using the mass you drop to wind it to hold the thing down as well.

[student2007]

the confusion to me is that the teacher specifically said it has to be some type of button, not like a lever or something, so my main question is how could i use a "button"?

 

one kid in my group said he could possibly make a crank which could possibly push down the cataplut and compress a spring and then another button could release it but we are not sure if we could get a strong enough motor because he normally deals with little stuff.

[Klaynos]

Have the button rigged to a lever, so it itself is a button that operates a lever...

[foodchain]

the confusion to me is that the teacher specifically said it has to be some type of button, not like a lever or something, so my main question is how could i use a "button"?

 

one kid in my group said he could possibly make a crank which could possibly push down the cataplut and compress a spring and then another button could release it but we are not sure if we could get a strong enough motor because he normally deals with little stuff.

 

Maybe some time of a slingshot with a button to release it? I would go with the crank idea also as you could basically just test different angles and how much to pull it back, seating of the egg and so on or what materials to use in it.

[ErlyRisa]

what a stu[id teacher....wasting ur time, not concentrating on the fundamentals of the principal behind the contraption...trajectory, and work.

 

so the rules are - safety princiapals must be observed (staged mechanism), user friendly : button activation.

Has to be light enough to be launched for space flight!?

 

--So you have to be a qualified mechatronist to build the dull thing.

---I presume this is a Higher Education experiment... with time to build the darn thing... but if I had to do it Viking Style without all the silly restrictions.

 

-Spoon on a Axle.

-string on another axle, with a weight on the end... with pre-pontential height.

 

-stage one... press button to release weight.(300grams-leaving 100 for balsa construction... I presume he wants you to calculate what 9.8h you need for trajectory of egg to hit pool at distance.) , the potential drop, winds a spring.

 

-Stage 2... release spring... which 'flips' the spoon on the axle.

 

Materails required... Rat Trap. Spoon. 2 Axles (1 is already in the Rat trap, just needs to be extended to 'set the trap', when the weight is droped. (consider just typing the string to the end of the trap, and making the string follow 'the right trajectory' to set it...ommiting the need for the axle (but may increase weight of overall contraption))

 

--then again, I highly doubt 300grams will set a rat trap, without about 10Metres of gearboxed drop height.... so change 'fly wheel weight'...ie decrease the diametre of your spring winding axle to suit... the smaller it is, the eaier to overcome impulse force.

 

* From a mathematical standpoint, you could calculate the most efficient 'height' to throw the egg at, Vs. the amount of E you are able to set in your catapulte.(ie the higher you go, the less E you have to use to throe the egg, but the more E you are able to gather into your spring...at some piont your '300grams' achieves what's desired in least amount of t at a certain height.)

 

 

as for buttons...well you could go electric, but if your any good at wood work, than you should be able to fashion some button mechanisms.