· The final design must include a minimum of three mechanisms including any of the simple machines: a gear system; a pulley and belt system and/or a sprocket and chain system.
The compound machine must have a mechanical advantage great enough to lift a minimum of 500g.
Brainstorming/ First Ideas
When we were brainstorming we wanted to design something that wasn't complex and was straight-forward. Our first idea we had a lever attached to a wheel and axel that would rotate enough gears to then turn a chain. We would have another wheel and axel at the end. For our second option we had a fixed pulley attached to a lever, and the lever was attached to gears/wheel and axel like our first design. Our third idea was for a pulley system to turn the gear train and to lift the weight using an inclined plane. We chose our first idea because the other two were a little too complex and we believed they wouldn't work as well.
Documentation
Our design worked precisely how we wanted it to. We put the small weight attached to the lever on the left of the image. We had the heavier weight on the right side of the photograph. When we would drop the small weight the lever would tilt which would rotate the gears which are attached to the string. When the gears would rotate, the sprocket/chain would rotate as well. A wheel and axel was attached to the sprocket and chain and would rotate the string upwards which lifted the heavier weight.
Calculations/ Documentation
Our calculations are shown. Our wheel and axel had an IMA of 1 because both of the wheel and axel and wheel with the string around it where the same size. Every time the wheel with the string would rotate once the wheel and axel would rotate once.
Final Design
Our final design worked. Everything worked out like we had expected. All of our calculations gave the machine an IMA (Ideal Mechanical Advantage) of 72. Our AMA (Actual Mechanical Advantage) was 3.33. The efficiency of our machine was only 5%, but it was enough to work.
Reflection
Despite having such a low efficiency, our design worked. Most of the friction came from the gears so if there is any part of this project I would change it would be the gear train. Another thing I would do is to do the calculations when we were building the machine so we could've gone back and changed the machine without changing everything.