Description of the constraint Inertial frame o-e Body-fixed frame of B,C y Define a vector attached on the axis is given Body-fixed frame of B; C,-e, a.)is given Point P and point Q are both located on the axis Define a unit vector parallel to the axis可， v is given Let h=2-”=可+9-月-，” h=r+A se-r-As• Description of the constraint Bj y  x  O j x y j   Cj j r  Q Q j r Q j s e  Inertial frame O  C j j e  Body-fixed frame of Bj    T T j j  j q  r Q j s   Q T j Q j Q j s  x  y  Point P and point Q are both located on the axis P i s Let   T T i i i q  r P i s   T P i P i P i s  x y is given C i i e  Body-fixed frame of Bi  i x  i y  Ci Bi ir  P P ir h  Define a vector attached on the axis j v  j v is given Define a unit vector parallel to the axis i v  i v is given i v  j v  P i Q j h r r      P i i Q j j r s r s         P i i i Q j j j h  r  A s  r  A s is given