MR-compatible hand exoskeleton for monitoring brain activity during active assistance

This work presents the mechanical design, implementation and evaluation of an MR-compatible hand exoskeleton that provides real-time monitoring of the joint angle, angular velocity and joint force produced by the MCP joint of the four fingers in an fMRI scanner. For force measurement, a novel optical type force sensor has been designed and implemented. The proposed hand exoskeleton is also capable of providing computer controlled assistive and resistive forces to the MCP joints using a non-magnetic ultrasonic motor, which allows the investigation of the brain activity during both passive (non-voluntary) and active (voluntary) movements. The MR-compatibility of the system was verified based on the analysis of SNR images of phantom tests and by the acquisition of human brain images.