Miniaturized triaxial optical fiber force sensor for MRI-Guided minimally invasive surgery

This paper describes the design and construction of a miniaturized triaxial force sensor which can be applied inside a magnetic resonance imaging (MRI) machine. The sensing principle of the sensor is based on an optical intensity modulation mechanism that utilizes bent-tip optical fibers to measure the deflection of a compliant platform when exposed to a force. By measuring the deflection of the platform using this optical approach, the magnitude and direction of three orthogonal force components (F_x, F_y, and F_z) can be determined. The sensor prototype described in this paper demonstrates that it can perform force measurements in axial and radial directions with working ranges of +/-2 N. Since the sensor is small in size and entirely made of nonmetallic materials, it is compatible with minimally invasive surgery (MIS) and safe to be deployed within magnetic resonance (MR) environments.