Need a realistic Statics Problem

[Chris Hibner]

Originally Posted by KenWittlief

our team discovered this a few years back. In the drawing, the red arms pivot at all four points on the black frame

the L shaped platform is moved up and down by the torque on the arms.

Now heres the weird part - moving the load (blue box) left and right has no effect on the amount of torque required to raise the arms

as if leverage no longer exists.

This is what I figured out the day after the 2002 kickoff. Our robot lifted the goals completely off the ground that year. My calculations showed that with a 4 bar linkage, the distance from the pivot became irrelevant as to how much torque was needed to lift the goals (the distance only changed the amount of compression and tension in the upper and lower arms). These calculations convinced our team to make the lifting robot - and it turned out to be not that difficult to do.

See, this is what an engineering education does for you. Without knowing statics, we probably wouldn't have attempted the lifting robot. That or we might have attempted and failed. It turned out pretty good for us that year. It was also a great message to our students to show how an education can help you solve difficult problems.