The Cylindroid Associated With Finite Motions of the Bennett Mechanism

The finite kinematic geometry of the Bennett mechanism is explored, and a surprising finding is uncovered in this paper. The screw axes of all possible coupler displacements of the mechanism from any given configuration are shown to form a cylindroid. The screw system of the coupler displacement is obtained by using the intersection of finite screw systems associated with two corresponding revolute-revolute dyads. Inverse finite kinematic analysis is also performed to verify this new linear property of the Bennett mechanism.