基于直线剪式单元的四棱锥放缩机构的设计与分析

In this paper, the linear scissorselement is extended to a variable hinge point linear scissorselement, and the motion mode of the scissors element is extended to space. A quadrangular pyramid scaling mechanism based on the variable hinge point linear scissorselement is proposed. The quadrangular pyramid expansion and contraction mechanism composed of linear hinged scissors element with variable hinge points is a complex multi-closed-loop structure. It is difficult to calculate the degrees of freedom using traditional formulas for degree of freedom. Therefore,its degrees of freedom is calculated with the screw theory. A theoretical basis is put forward for the practical application of the quadrangular pyramid scaling mechanism.