Automated MRI Electric Field Measurement System

In this project during an internship with LivaNova, I designed an automated system to measure the electric field inside an MRI machine, addressing the inefficiencies and inaccuracies of the current manual process, which typically takes around 2 hours and is prone to human error. The electric fields, generated by the MRI’s RF power, are crucial for calculating the heating effects on metallic leads within the body. My goal was to automate the measurement of 42 key points within a phantom model using a probe controlled by a Zaber gantry system for precise motion.

The system needed to meet several critical requirements: the probe tip had to be maintained at a height of 4.5 cm (±1 mm) above the bottom of the phantom, and the entire setup had to fit within the MRI’s birdcage coil without using ferrous materials, which could disrupt the magnetic fields. I designed the system with several integrated subsystems, including side rails, a carriage, and a probe holder. The side rails were made from non-conductive materials and attached to existing holes in the phantom. I carefully designed them to avoid interference with the MRI’s coil while ensuring the rails extended far enough to allow full probe reach.

The carriage, supported by ball bearings and angled rollers, allowed for smooth movement along the rails. The probe holder was designed for flexibility, featuring two configurations to reposition the probe at different angles without colliding with the coil. Additionally, I integrated a Zaber arm to control the precise movement of the probe along the rails, ensuring accurate electric field measurements.

By automating this process, I was able to reduce the measurement time from 2 hours to just 30 minutes, greatly improving efficiency while minimizing the possibility of human error. The next steps in this project included sending the technical drawings for machining, ordering the necessary off-the-shelf components, and preparing for the system’s construction and testing phases. This project not only streamlined the electric field measurement process but also enhanced the overall reliability of the data collected.