The Unofficial LEGO Technic Builder's Guide, 2nd Edition

8levers and linkages

Levers and linkages are some of the simplest machines and form the basis for countless more complex mechanisms. While levers are mostly used to provide a mechanical advantage that allows us to move heavy loads, linkages are mostly used to transform one type of a motion into another. Both are common in everyday life: If you have ever played on a seesaw or used pliers, you have relied on levers and linkages.

levers

A basic lever is simply a beam that has one point of support in the form of a hinge or a pivot, as shown in Figure 8-1. We will call this point a fulcrum. A lever also has input and output forces. We will call the applied, or input, force the effort and the reaction force the load. Finally, we will call the sections ...