Figure 4.1 A Sarrus linkage where its axes, 1, 2, . . ., 6, are represented by
arrows.
(a)
(b)
(c)
Figure 4.2 (a) A spatial closed chain consisting of four conventional scissor-like
elements. There is a Sarrus linkage whose axes are marked as 1, 2, . . ., 6
at each corner; (b) schematic diagram representing the top projection of
the spatial chain; and (c) the same diagram when joint size is neglected.