Cremona diagram

Summary

A Cremona diagram is a graphical way to find the forces in the bars of a plane statically determinate truss. It joins the force polygons of all the joints into one drawing. In it each bar force appears exactly once, as a segment parallel to the bar. The bar forces are then read off as lengths, without solving equations. It is named after Luigi Cremona and is related to the reciprocal figures of James Clerk Maxwell.