Abstract:

Based on a new method-GOM formula referred to before, which was expressed with “DOF of general link-group”, steps of calculating DOF with this idea were established firstly. Meanwhile, displacement parameters of basic link-groups commonly used were listed and a method of determining the rank of link-group was introduced. Secondly, a theory which could quickly determine the DOF and motion characteristics of output part was determined. Finally several typical examples from the literature were performed to illustrate the accuracy and validity of the new theory mentioned above. The results show that this new formula can avoid calculating virtual constraints, and without the aid of sophisticated mathematical tool, the DOFs of mechanisms including hybrid mechanisms can be calculated quickly and availably. In short, its accuracy and versatility get a test in a certain extent.

Key words: degrees of freedom(DOF), virtual constraint, multi-loop coupling, parameter of link-group

摘要：

总结了利用GOM公式计算机构自由度的具体步骤，列举了常用基础杆组的位移参数，介绍了杆组阶的确定方法;给出计算输出构件自由度及快速判断构件运动性质的方法;选取了几种典型的机构验证了所提出方法的正确性。结果表明，该新公式可以避开虚约束计算，不需要借助复杂的数学工具，便能快速、有效地计算包括混联机构在内的机构自由度，其正确性与通用性在一定程度上得到了验证。

关键词: 自由度, 虚约束, 多环耦合, 杆组参数