Loop-construction mechanism and its network based on quadrilateral mechanisms

Aiming at the construction method and theoretical analysis of deployable mechanism, the construction method of loop-construction mechanism based on quadrilateral mechanisms and the network mechanism are proposed. Firstly, the construction method of the loop-construction mechanism is given, and the constraint conditions of the mechanism are derived. Two types of loop-construction mechanisms based on the Bricard mechanisms are obtained, namely the plane-symmetric and the generalized trihedral loop-construction mechanisms. Then, the constraint conditions and kinematic paths of the two loop-construction mechanisms are analyzed respectively. Thirdly, a special threefold-symmetric loop-construction mechanism is obtained, and based on the regular hexagonal shape characteristics of the mechanism, the construction method of network mechanism and the motion characteristics are given. Finally, four prototypes are fabricated to verify the correctness of the analytical results and the feasibility of the construction method.