如何在Pipe 一端加弯矩？

如题：我做一简单例子，利用MPC 和reference point 加弯矩。
但是没有结果。
warning大致是这样：
MPCS (EXTERNAL or INTERNAL, including those generated from rigid body definitions), KINEMATIC COUPLINGS, AND/OR EQUATIONS WILL ACTIVATE ADDITIONAL DEGREES OF FREEDOM
Degree of freedom 6 is not active in this model and can not be restrained
Degree of freedom 6 is not active in this model and can not be restrained
Nodes 1 instance part-1-1 and 1 (assembly) in the tie mpc are not coincident. The mpc will constrain rotational rigid-body motion between the nodes. Interpret results with caution or consider substituting a beam or link mpc.
重复这一行的内容。
inp 和dat文件放附件中。