We have already proposed an identification method of inertial terms of a robot arm based on the mass loading effect of mechanical resonance. This method assumes that the mechanical cramp is prepared for every joint axis except for the measured joint. Although the measurements are performed without mechanical cramp. Analyzing the effect of identification accuracy under the condition of non-mechanical cramp, it is clarified that some estimation errors due to the coupling vibration occur. In this paper, we propose a modified identification method of inertial terms with the positive feedback of velocity and acceleration.