DoubleCrank
Doublecrank, in mechanical engineering, refers to a four-bar linkage configuration in which both the input and the output links are cranks, meaning each can undergo continuous rotation about its fixed pivots. This arrangement contrasts with crank-rocker (one crank and one rocker) and double-rocker (two rockers) configurations. A doublecrank mechanism typically consists of a fixed frame and three moving links, with the two end links attached to the frame as cranks and the middle link acting as a coupler that transmits motion between the cranks.
Kinematically, a doublecrank provides a single degrees of freedom for the whole linkage, since the relative
Design considerations for a doublecrank include satisfying length conditions that permit full rotation of both cranks
History and study of four-bar linkages, including the doublecrank configuration, trace to foundational work in kinematics