for my machine, I used several household items to make a machine that would pour water into a cup.

I used a soccer ball, some books, some boxes, game cases, Jenga blocks, a binder, a skateboard, and a water bottle and a glass cup.

it works by you pushing the ball down the books, it knocks over the Jenga tower that then knocks over the ball that rolls down the skateboard and knocks over the game cases that fall over and knock over the binder and makes the water pour into the glass.