Magnetic Resonance Imaging (MRI) has multiple advantages over other types of medical imaging. For instance, it allows for high contrast imaging of soft tissue in three dimensions, and it does not expose patients to ionizing radiation. Researchers have shown an increased interest in robot utilization combined with MRI modality. One of the advantages is the possibility to perform real-time image guidance. In this way, diagnostic patient information and robot instrument tracking can be performed at the same time, reducing the procedure time significantly. To create robotic systems with sufficient accuracy, it is important to have sensors that can provide position feedback of robotic elements when operating in an MR environment.
Problem
Fibre optic sensing has been used in several applications in the MRI environment. Although it can provide high accuracy measurements, the system is not compact, and it requires expensive equipment to operate, such as an optical spectrum analyzer. Another alternative for an MR-compatible sensor is to use a pneumatic-based system. Some MR-compatible robotic systems have been proposed to use pneumatic actuators. Harnessing the power of the pneumatic power source that is already available for these actuators, it may be possible to create a pneumatically based position sensor for the moving elements of such a robot.
Can one design a pneumatic position sensor to provide feedback to a robot inside an MRI scanner?