A Novel tele-operation controller for wireless microrobots in-pipe with hybrid motion

Intracavity intervention is expected to become more and more popular in the medical practice, both for diagnosis and for surgery. Wireless microrobots are employed in a wide range of biomedical application, they have many potential to accomplish many medical procedures radically, which is due to they can be carried deeply within the body of living organisms to perform tasks safe and reliable. The method of colonoscopy is an important procedure for the diagnosis of various pathologies, especially in cancer of the colon and rectum. However, it is often painful to the patient and complex to the doctor during the colonoscopy process, so the wireless microrobots have been very necessary for early diagnosis of malignant tumor in gastrointestine (GI). In this paper, a novel tele-operation system which would be used in the biomedical application has been proposed, and the master controller and slaver controller in the system had been designed. We also designed a novel kind of wireless microrobot with hybrid motion which driven by the different external magnetic field. The doctor could operate the joysticks from the master side to control the wireless microrobot in slave side in real time. With the control algorithm of 8-Steps rotation magnetic field, the slave controller could generate a more uniform rotation magnetic field and avoided many problems that occurring in traditional control method. Based on some experiments, the performance between the tele-operated controller and the wireless microrobot with hybrid motion had been evaluated. The experimental results indicated that the wireless microrobot with hybrid motion could complete forward-backward, upward-downward motion easily with the similar kinematic characteristics, and the available frequency band would be widened with the control algorithm of 8-Steps rotation magnetic field. Besides that, the maximum velocity could be measured at 29.8 mm/s round 18 Hz in the horizontal direction and 9.6 mm/s round 16 Hz in the vertical direction with input current of 0.7 A. The tele-controller showed a good performance in the experiments and it would be widely used in medical clinic in the future. Research highlights ▶ A novel tele-operation system for the medical application have been proposed, and the tele-operation controller in the system also have been designed. ▶ A novel kind of wireless hybrid microrobot with gravity compensation mechanism have been designed. ▶ The control algorithm of 8-Steps rotation magnetic field have been proposed to improve the quality of rotation magnetic field. ▶ Some experiments have been taken to verify the feasibility of the 8-Steps control algorithm and the tele-operation system.