chapter  6
19 Pages

Spatial motion structures based on Bricard linkages

The Bricard linkages reviewed in Section 2.3.5 are the only 6R overconstrained linkages that are not derived from 4R, 5R or other 6R linkages. Of a total of six types of Bricard linkages, the most suitable ones for the purpose of constructing motion structures is the threefold-symmetric Bricard linkage, obtained by combining the general plane-symmetric and trihedral Bricard linkages. The geometric parameters of the linkage satisfy the following conditions.