Overview of Status of Analysis, Design, Fabrication, Tests, etc.
The 31g stylet and cannula pushed through a path at a 45 degree insertion angle does not penetrate 6mm polyethelene
Result of stylet buckling analysis show that a 31g stylet will buckle
System dynamics analysis provided the amount of time and deflection the stylet requires to reach the required speed for penetration
Accomplishments from Previous Week
System Dynamics modeled with matlab (Maverick)
Glossary Page added to Report, Report and website emailed to Sponsor (Ryan)
Device fabricated with a the 31g stylet and cannula pushed through a path (Peter)
Stylet buckling analysis complete - linear (Dohwan)
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Design and implement a method for stylet retraction (Peter and Maverick)
Polish off the report (Ryan)
Stylet buckling analysis via Solidworks FEA (Dohwan)
Test device reliability- how many launches can it perform without failure (Maverick and Peter)
Add necessary files to the webpage (everyone)
Order Adhesive pads for the device (Dohwan)
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Conference call via UberConference 5/18/17 2:30pm-3:20pm
Where does three day usage guideline come from?
Industry accepted guideline that stems from IV guidelines and insulin deliverers after a patient experienced negative side effects after 9 day usage
Final Product Information
Housing will be injection molded with polypropelene or plastic polycarbonate
Use provided 31G Stylet (Solid)
Reconsider deliverables
1:1 scale prototype, no longer pursuing 3:1 scale prototype
Focus on penetration of stylet with cannula, no longer pursuing automatic retraction
Perhaps change the angle of insertion
Sponsor Final Review
Due to Kennie's availability, sponsor wants to have the final review on either 6/1 or 6/2
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Instructor Meeting; Monday 5/15; Dr. Tustaniwskyj, Pedro Navarro
Consider changing the stylet geometry for the device to work
Shortening, or thickening the stylet, or a combination of both
Dohwan performed buckling simulations using combined modulus of nylon and steel to determine the thinnest stylet that would theoretically work
Energy analysis to determine the speed is insufficient
Perform dynamic mass-spring analysis model the system position and velocity
Consider a channel to fully constrain the stylet within the housing unit
Perform spring fatigue analysis
Comments from Other Students in the Class (indicate date of comments and if via email or in person)
n/a
Risks and Areas of Concern
To use 3d printing or upgrade into injection molding
Reliability: how many successful launches can we get before failure
Needle buckling possibility
Client does not want to modify specification of the stylet and cannula
Resources or Information Required but not Available
A source stating the length of time an insulin catheter can remain in the body
Schedule
Describe upcoming milestone
05/22/2017: Preliminary Design Review
06/05/2017: Final Design Review (tentative schedule)
Update Gantt chart.
Completed
Budget (list amount spent and amount remaining)
Budget:$700.00
Spent: $295.77
Remaining: $404.23
Progress on Report and Webpage
Report
First Report Draft is on the docs tab of website
Webpage
CAD files are on the site
Budget is updated