Development and evaluation of a portable MR compatible haptic interface for human motor control

This paper presents the development and evaluation of an MR compatible haptic interface for human motor control studies, which can be easily installed and removed from the scanner room. The interface is actuated by a powerful shielded DC motor located 2.1 m away from the 3T MR scanner. Rotational movements are transmitted to a subject's wrist through preloaded cable transmission which drives the handle unit. The handle of the interface is designed to be adjustable to different hands size, enabling comfortable and natural wrist movements. The nominal achievable wrist torque of the interface is up to 2Nm. The interface is easily transportable due to its design characteristics. A dynamic model of the interface is presented and identified for position and torque control modes. Phantom MR compatibility test in clinical environment showed that the interface is compatible with strong magnetic field and radio frequency emission and its operation does not affect the quality of MR images.