Design Progress | Week 5

Dates: 9/17/25 - 9/23/25

This weeks progress was made across documentation, materials research, prototyping, and component updates. The Monetary Expenses page, submenu, and push button pricings were updated to reflect current costs, and two dedicated logs were created: one to track actual expenses from the materials and parts already used, and another to estimate project costs for a full build.

The design task timeline was also revised back to its original version following feedback from Dr. Ejaz, and the Gantt Chart was updated to include these adjustments along with the week’s overall progress.

In terms of engineering specifications, the previous Darlington array motor driver was replaced with the more efficient TPL7407LA MOSFET Motor Driver, and the updated switch specifications were incorporated into the revised documentation.

On the research front, I reviewed the material properties and printing considerations for PLA, ASA, and TPU, focusing on their differences in temperature handling and structural performance. I also studied solder brass M# screw heat press methods through instructional videos and specifications to better understand how these apply to various 3D printing materials and form factors.

Prototyping efforts concentrated on reprinting the faceplate using ASA rather than PLA. The original PLA prints for both the faceplate and face shield had cracked due to brittleness, which prompted the material change. The reprint process has gone through five iterations to date. The first ASA print caused unwanted mixing with TPU, leading to adhesion issues. Prints two through four required fine-tuning of software parameters such as support threshold angle, brim width and style, and infill type. Additionally, I performed maintenance by cleaning and greasing the printer rails to address abrasion and tread that were causing recurring deformities. These adjustments have steadily improved the quality of the ASA faceplate prints.

Finally, several electrical and component updates were completed. Both momentary and latching switches were purchased for upcoming assembly and functional testing, with a design change to use 12mm push buttons instead of 16mm to ensure proper spacing within the NAVI enclosure.

Shown below are the failures for the ASA reprint of the Faceplate