I was tasked with replicating a testing setup for a steerable needle developed for interstitial brachytherapy to treat cervical cancer under the guidance of Mohammad Afrazi as a researcher in the Duke Bertram Lab. This setup facilitates assessment of steerable stylets and characterization of their behavior within phantom tissue. 

I was provided with the Autodesk Fusion files for the testing setup, and created a Bill of Materials (BOM) in Excel to manage the sourcing/creating of 60+ unique parts that had to be both sourced and manufactured. I integrated procurement links into the BOM, as well as columns to track which parts had been successfully 3D printed and post-processed.

Manufacturing for the experimental setup included both additive manufacturing with 3D printers and subtractive manufacturing using a laser cutter. Issues arose when one 3D printer began to experience "spaghetti" errors, in which plastic is extruded into mid-air. To troubleshoot, I cleaned the build plate to ensure proper adhesion, adjusted slicing settings to have more conservative supports and ensure the plate wasn’t overcrowded, and then performed cold pulls to clear the nozzle and extract debris, all of which were ineffective. This led to a pivot to using other available 3D printers, where I was able to successfully print the rest of the necessary parts. I experimented with various slicing options in order to optimize the prints, settling on snug supports that were not restricted to the build plate. 

For subtractive manufacturing, I created .dxf vector files by projecting necessary geometry, such as holes and perimeters, onto a sketch in Fusion. I then imported the .dxf into Adobe Illustrator, ensured the proper stroke settings for the Trotec Speedy 400 laser cutter, and exported the file to be sent via Trotec’s Ruby cloud service.

Once I had laser cut the acrylic pieces, I used a tap to thread the laser-cut holes to create custom mechanical breadboards that I would build the setup on top of.

This project is currently a work-in-progress. My next steps are to assemble and ensure precision of the setup.