Magnet Array-Actuated Steerable Flexible Robot with Beacon-TFM Ultrasonic Position Sensing for Robotic Neurosurgery

A magnetically controlled steerable robot with the capability of flexible navigation and intraoperative ultrasonic imaging and position sensing in neurosurgery is introduced in this paper. The robot system uses a piezoelectric transducer as the ultrasonic imaging beacon and applies a permanent magnet as the actuation unit, which can steer the flexible robot following a planned complex path to access a target in the brain. In order to enable the robot to navigate flexibly within tissues, a method is proposed to enhance magnetic actuation force by utilizing an array of small magnetic blocks instead of using a large magnet. The improvement of the array for magnetic field distribution was verified by simulation. Simulation studies also involved modeling the ultrasonic transmitting and receiving functions of the piezoelectric transducer to verify the feasibility of using them for intraoperative imaging. In addition, a prototype of the robot is fabricated and tested. The feasibility of the proposed magnetically controlled steerable robot for navigation in soft tissue is verified.