The method of calibration for the robot arm capable of adjusting position of the center of gravity and the evaluation of the motion in the air

Abstract

The motion of an arm installed to a multicopter can possibly disturb its orientation. To realize an aerial manipulation by using a multicopter with a robot arm, a control of its center of gravity (COG) is required. In previous study, we proposed a design method for the mechanism of a robotic arm suitable for a multicopter. In the proposed design method, the arm can adjust its COG due to redundancy degrees of freedom. For safe flight, however, it is necessary to obtain its parameters utilized for multicopter control before take-off. In this research, we propose a method to estimate parameters to adjust COG with simple experiment before take-off. Moreover, to suppress the number of times of measurements and parameters variation, we obtain appropriate calibration orientations by simulation and confirm the effectiveness by calibration experiment using the obtained orientations. Finally, we fly a multicopter with the developed arm and observe a rotational speed of the propeller using a high-speed camera and evaluate the effect of the arm movement on the multicopter.