The solid model of the grab manipulator is established by using UG

at the same time

by using the motion analysis module of UG

the manipulator arm position and the end of the actuator motion simulation are carried out.For the problem that the manipulator easily capsize in the process of work

waist can be bent by the excessive role of the overturning moment

thus the movement of robot in the vertical direction.Using Nastran embedded to UG

the finite element analysis of waist is carried out

maximum stress is obtained

compared with the calculated stress

the commitment of the smooth work

and the future design improvement of the manipulator is provided.