Development of a Wearable Robotic Positioning System for Noninvasive Transcranial Focused Ultrasound Stimulation

Transcranial ultrasound neuromodulation has been attracting more and more interest from researchers as a novel modality for brain stimulation. Typical manual positioning for brain stimulation requires the patient to sit still during stimulation for extended periods and readily loses its positioning accuracy if the patient moves. To address these problems of inconvenience and inaccuracy, we proposed a robotic positioning system for targeted ultrasound brain stimulation. The proposed device automatically moves the ultrasound transducer to a desired position and orientation, enabling far more accurate and comfortable automatic positioning of the transducer than when using traditional manual positioning. The device was developed as a wearable design, because it eliminates the necessity for troublesome motion compensation for the user's unintentional movements. Parallel and serial mechanisms were combined and a torque optimization method was proposed so as to obtain a lightweight design, and to implement a sufficient number of degrees of freedom of motion.