# Pivot points within a 7 point hinge

Please see the attached file for the fully formatted problem(s).

My problem is explained more in my attachment, but briefly, I require some form of equation or graph to calculate where the pivot points within a seven point hinge system need to be in order for the rotating edge to rotate around a origin.

The question is in regard to the hinge system.

I require the hinge, when expanded, to rotate around the origin with 0 tolerance.

THE HINGE

What I know

Through pure trial and error, involving no mathematical formulas or graphs, I have

narrowed down where the pivot points, approximately need to be placed so it rotates

around the origin.

I did this by lengthening and shortening distances and angles between points, until I

narrowed the solution down to be within 2mm tolerance.

As can be seen in the picture below, the plate that will be used to bend the material

moves up/out/in/and down while rotating around the origin. I require this plate to have no

tolerance, i.e. not move away from the origin at all. Therefore I believe there must be

some sort of graphs or equations that will dictate exact positions the pivot points within

the hinge need to be.

Bending Edge

Origin

Bending edge shown here at different stages of rotation

https://brainmass.com/math/graphs-and-functions/pivot-points-point-hinge-5099

#### Solution Summary

The pivot points on a seven-point hinge system are determined. A function rotated around the origin with the tolerance is found.