关于自由度的计算

关于自由度的计算，已经引起了世界上许多学者的注意。本文提出了“根据机械系统的闭合特点，割断机架分析末杆运动，在同一瞬间把末杆与机架焊接，重新形成原机械系统”的理论，来计算机械系统（包括机构、结构）的自由度。本文阐明了机械系统中的静不定次数和自由度数的内在联系；为判断机械系统能否实现有限位移提供了必要性判据，同时为判定机械系统是否能作为结构提供了充分性判据；揭示了静不定和自由度的物理意义；严格地说明了把机构分成六个族是错误的，机构分族的观点是毫无意义的。根据上述理论，我们导出了闭合数计算公式、自由度数计算公司以及静不定次数计算公式。用这些公式可以毫无例外地按机械系统（包括机构、结构）的构造，正确地计算出它的自由度数和静不定次数。

ONCALCULATON OF DEGREES OF FREEDOM OF MECHANICAL SYSTEM

The calculation of degrees of freedom of mechanism has attacted many scholars' attention all over the vv orld. This paper has put forth a theory concerning the analysis of the motion of the end member which is assumed to be cut off from the frame temporarily according to the closed loop characteristic of mechanical system, and immediately welded to the origiinal frame of the mechanism back again to reform the original mechanical system, and the theory is applied to calculating the degrees of freedom of mechanical system (inclding mechanisms and structures) . This paper elucidates the internal relationship between the degrees of statical indeterminacy and the degrees of freedom in mechanical system. It creates a necessary criterion for determining whether the finite displacement occurs in the mechanical system, and a sufficient criterion for determining whether the mechanical system can serve as a structure. It also reveals the physical concept of statical indeteerminateness and degrees of freedom, and finally proves exactly that the previous theory to classify the mechanism into six families is wrong, and that the classification of mechanism into families makes no practical sense at all.