Design of Test Fixtures for Protective Devices Used in Endoscopic Skull Surgery

Overview

A team of PSU researchers are developing a device to seal the nasal and oral cavities during endoscopic skull surgery. This device is needed to protect clinicians and others in the OR from aerosol droplets generated by patients with COVID-19 or other infectious respiratory conditions. These devices will be filtration tested for efficiency. Specially shaped test fixtures are needed to adapt the devices to the testing chamber. The Capstone team will deliver SolidWorks designs and physical test fixtures that seal and secure the devices to the testing chamber.

Objectives

-Design and fabricate test fixtures used to assess nasal coverings for endoscopic skull surgery.

-Fixtures cannot shed particles or leak and should allow various devices to be secured to the testing chamber.

Approach

-Collected customer needs and requirements via direct communication with the sponsor and the equipment operator.

-Generated concepts individually and collaborated between the team members to identify overlap of ideas. Utilized concept selection matrices to choose which ideas were worth pursuing.

-Investigated mask sealing solutions utilized by other universities during filtration testing. Consulted a materials expert to advise on material particle shedding.

-Created CAD models and assemblies to simulate form and fit.

-Confirmed proof of concept by the 0th prototype whereas the alpha and beta prototype were used to refine the design according to design specifications.

-Evaluated material and seal integrity by rapid prototyping with particle testing. Utilized percent difference between testing chambers to determine success for particle shedding.

-Tested porosity by filling the fixture cavities with water and identifying leakage. Tested fit by affixing the developed fixtures to the test rig and performing a visual inspection.

Outcomes

-Set-up time was reduced ~50% with the introduction of spare parts and semi-permanent fixtures which reduced the number of parts in the assembly

-Test fixtures achieved no significant difference in particle count between testing chambers

-Two unique testing fixtures are developed that can be utilized to test multiple nasal device designs

-Variability in testing procedures is reduced as a result of outlining a standard operating procedure