Development of a novel wireless microrobot in-pipe with hybrid motion

Non-invasive into the human digestive tract or artery, complete minimally invasive or non-invasive diagnosis and treatment have become a hot pursuit of the current international biomedical field. In this paper, a new kind of hybrid motion wireless microrobot in-pipe with gravity compensation had been designed, which had a more compact structure. By switching the rotation magnetic field and alternating magnetic field, the microrobot could realize the rotation motion and fish-like motion in pipe immediately. The microrobot with gravity compensation designed mechanism could achieve forward-backward and upward-downward motion in pipe easily with the similar dynamic characteristics and more efficient by much simpler control strategies. Based on the experiments, the effect on the spiral motion and fish-like motion had been evaluated. The experimental results indicated that hybrid microrobot Type A is superior to Type B, the maximum velocity of hybrid microrobot Type A is 29.5mm/s at 15Hz in the horizontal direction and 8.7mm/s at 14Hz in the vertical direction with input current of 0.7A. The wireless microrobot in-pipe controlled by external magnetic field will play a significant role in both industrial field and medical applications. Furthermore it will bring the gospel to diagnosis and treatment of the human gastrointestinal tract disease in the future.