The line-symmetric octahedral Bricard linkage and its structural closure

This paper deals with one of six distinct types of Bricard 6R linkages, the line-symmetric octahedral case. By analysing the closure equations of the linkage, we have found that with the six zero-length links of the same twist and the six revolute joints of the same offset, a special line-symmetric octahedral Bricard linkage can be formed. Moreover, one or two structural closures always exist with the identical set of links and joints. This characteristic could be used for the reconfigurable structure design.