在多体动力学分析中加了刚性连接RBE2,但结果出现变形，什么情况的？

提示如下：

 *** INFORMATION # 742
 The dependent rotational d.o.f. of this rigid element is removed.
     RBE2 element id =   146982
 independent grid id =    36030
 a dependent grid id =     9657
 This is because there is no need to constrain the rotational d.o.f. of
 any of the dependent grids.