Abstract: This paper studies dynamic force analysis on one to six DOF multi-loop spatial mechanisms, and presents the kinematic influence coefficient method for dynamic force analysis. A numerical example on four-DOF spatial mechanism is given. As the force analysis of all pairs can be independently completed in each branch and all formulas are only multiplication of six-order or three-order matrices, it breaks through all methods before which must simultaneously solve a large number of linear equations for total mechanism.

Key words: 等效力矩, 动力分析, 空间机构, 影响导数, 自由度