Hello, i am currently working on a project for class where i have to launch or, preferably, lift a small cylindrical mass of 200 g. All the details are in the picture attached. So far, for ideas, i'm thinking of maybe making a scissor lift, but i don't really know how to make it actually lift. I know that car jacks, you pump a lever down and it lifts up, but i don't understand how to build that. All i know so far is how to make the "scissors" part from watching http://www.youtube.com/watch?v=TlniJGScpc0
Now i just need to know how to make a little lever or something to make it lift. I then need to figure out how to make it start lifting itself to a specified height of maybe 110 cm because all i can do is set up and start the device, but i can not do anything to it afterwards. So i was wondering if anybody had any ideas of how to go about making this. My second idea is also to make a trebuchet, but i don't know how accurate those will be or how to make it adjustable. Also i can't have it launch stuff too fast because i would get my grade lowered for destroying any equipment and the mass has to start off touching the ground so i will probably have to use a bax around the mass with a little hole on the bottom so that it is technically touching the ground and connect it to my machine with a string. Anyways, if anybody has any ideas of what i can make, i would appreciate it. Especially if it adjustable to that i can get the extra credit.