Integrated System Build & Test
Table of Contents
Team Vision for Integrated System Build & Test PhaseThe team's goal for this phase was to define user inputs for device movement as well as finish machining device parts. Static cell culture testing was performed to test the cell attachment and longevity in PDMS cell culture chambers. Material testing was completed to confirm the strength properties of heat-cured and incubated PDMS.
Test Results Summary
Material testing per ASTM standard D638 was repeated for heat cured PDMS (100oC, 35 minutes). Incubator and Standard (Non-Incubator) conditions were tested and compared to ensure that 10:1 PDMS can withstand operational conditions. The data collected found average Elastic Moduli for Standard and Incubator conditions to be 3.116 MPa and 3.266 MPa respectively. Tensile Strength values were found to be 2.052 MPa for Standard conditions and 2.07 MPa for Incubator conditions. This data suggests that material properties stay relatively consistent between Standard and Incubator conditions. The average yield strength was recorded as 6.7 MPa by DOW corning; however, it is known that heat curing can affect the material properties of PDMS. The observed Moduli, Tensile Strength, and Maximum Strain for our samples appear desirable for operational conditions.
Static cell testing was performed in room temperature cured PDMS chambers. The bottom of these chambers were coated with collagen (concentration 12.5 microgram collagen / cm2 PDMS). This coating proved to be sufficient for cell adherence. The pictures presented below were captured using an imaging microscope. The striation marks visible on the chamber were the results of using 3D printed molds. These should be diminished once the final machined mold is completed.
Machining TrackingFinal machined assembly is awaiting several parts. The spreadsheet below tracks progress of machining.
Risk and Problem TrackingLimited time until the end of MSD increases the risk that the team will not have time to test experiment conditions on the device. Experiment condition testing can begin once the device is fully assembled.
Bill of Materials
The team purchased mostly cell culture and machining materials this semester. About $350 still remains in the budget.