Kinematic diagram

In mechanical engineering, a kinematic diagram or kinematic scheme (also called a joint map or skeleton diagram) illustrates the connectivity of links and joints of a mechanism or machine rather than the dimensions or shape of the parts.

Often links are presented as geometric objects, such as lines, triangles or squares, that support schematic versions of the joints of the mechanism or machine.

[1] For example, the figures show the kinematic diagrams (i) of the slider-crank that forms a piston and crank-shaft in an engine, and (ii) of the first three joints for a PUMA manipulator.

[2] An important consideration in this design process is the degree of freedom of the system of links and joints, which is determined using the Chebychev–Grübler–Kutzbach criterion.

Higher order joints also exist that allow a combination of rotation or linear motion.