错误提醒：Three factorizations in a row failed. Check the model. It is possible that the model contains the kinematic coupling definition set up in a way that a degree of freedom has neither mass nor stiffness.（三次分解失败，检查模型，则该模型可能包含以自由度既没有质量也没有刚度的方式建立的运动耦合定义），查了很多，没有关于这个错误的信
息，已经卡三天了，恳请大神指点一二，导师急要，help！！