Motivation: Traditional MRIs are inaccessible in point-of-care scenarios or rural areas; portable MRI devices are proposed but remain inflexible and costly. Goal(s): Prototype a miniature MRI device suitable for various use cases. Approach: Three rotating permanent magnet arrays create unique field map patterns at discrete time steps, providing the base magnetic field and spatially encoding the information. A series of excitation frequencies allow volumetric "slice" selection, where signals are back-projected and overlaid to create the image. Results: Preliminary results from the prototype prove the feasibility of our approach. Simulated results further demonstrate the prototype's capability of 2D imaging at the cost of image quality. Impact: The preliminary prototype embraces inhomogeneity in the base magnetic field, eliciting a new direction for MRI instrumentation. Its ability to produce pilot scans allows for early diagnosis while reducing costs and providing patient comfort, ultimately making MRI technology more accessible.
Shi et al. (2025) studied this question.