Manipulator Control of the Robotized TMS System with Incurved TMS Coil Case

• Published in: Applied sciences Vol. 14; no. 23; p. 11441
• Main Authors: Kim, Jaewoo, Yang, Gi-Hun
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2024
• Subjects: Accuracy; Calibration; Cameras; Friction; hybrid position/force control; Magnetic fields; Navigation systems; Planning; robot manipulation; Robots; torque control; Transcranial magnetic stimulation; Velocity
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app142311441

This paper proposes the force/torque control strategy for the robotized transcranial magnetic stimulation (TMS) system, considering the shape of the TMS coil case. Hybrid position/force control is used to compensate for the error between the current and target position of the coil and to maintain the contact between the coil and the subject’s head. The desired force magnitude of the force control part of the hybrid controller is scheduled by the error between the current and target position of the TMS coil for fast error reduction and the comfort of the subject. Additionally, the torque proportional to the torque acting on the coil’s center is generated to stabilize the contact. Compliance control, which makes the robot adaptive to the environment, stabilizes the coil and head interaction during force/torque control. The experimental results showed that the force controller made the coil generate a relatively large force for a short time (less than 10 s) for the fast error reduction, and a relatively small interaction force was maintained for the contact. They showed that the torque controller made the contact area inside the coil. The experiment also showed that the proposed strategy could be used for tracking a new target point estimated by the neuronavigation system when the head moved slightly.