In this post, I will explain how to Tchebicheff straight line generator work? It this 4 bar linkage mechanism type. What is special?
As picture above, this mechanical mechanism has 3 bar. Purple bar can rotate around yellow pin. Green bar can rotate around orange pin. Blue bar can rotate around red pin that follow green link and pink pin that follow purple link. In this example, length of purple link and green link are same. Mid point of link blue describes a straight line when driven by either link purple or green.
You can see this video below for detail.