Week 2

Overview of Status of Analysis, Design, Fabrication, Tests, etc.

• • Modifying the basic plug based on feedback from Dr. Kalmaz, Dr. Gillet, Young, and other students.

Accomplishments from Previous Week

• • Finished risk reduction testing, and even tested a simple seal and clamp. 

  • Printed out seals of different durometers and inner diameters to find the optimal dimension and softness.

  • Printed a model plug out of PLA to get a feel for the shape.

Goals for Next Week (list names after each item). Use specific and measurable objectives.

• • Print out a new version based on Wednesday meeting with Dr. Kalmaz and show it to her for feedback.

  • Get started on clamp designs.

  • Think about designing for manufacturability.

Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)

• • Based on the green plug, Dr. Kalmaz wants a flap added to the design. 

• • So we went ahead and printed a design with a flap on Friday. We also took feedback from students who felt that extra flap was excessively big, and so we shortened the diameter to be 1/2 the distance between the OD of the plug, and the OD of the flange.

Instructor Comments from Last Meeting and Actions Taken to Address these Comments  (indicate date of comments and if via email or in person)

• • Informed consent not enough to do human trials. It takes a lot of paperwork and time and bureaucracy just to get a proposal to the committee. 

  • Swine is a good analog for human skin. Inside pigs, not too sure. gotta do research. It won't be easy testing on pigs. 

  • we need to cast in order to do human testing out of biocompatible material. 

  • PDMS curing is an art. No guarantee on material properties. Gotta get rid of air bubbles, cure at high temperature. So people use a vacuum chamber and heat it up but may be too complicated for us.

  • For us, stir it at high temperature. PDMS needs curing agent. Timeframe for cure is hours.

  • Ecoflex would drip right off our part if we were to dip it in. Takes hours to cure, we can't coat our part in that stuff.

  • (Gillet 13 April 2017)

  • Use the overtube as a size reference.

  • New material for Stratysys we can use that's more rubbery and less susceptible to tear.

  • (Young 13 April 2017)

Comments from Other Students in the Class (indicate date of comments and if via email or in person)

• • Flap is too big, make it smaller, may hurt. Maybe have an insertion device for the plug. 

  • (Stuart 13 April 2017)

Risks and Areas of Concern

• • design may not work with a clamp.

Resources or Information Required but not Available

• • casting PDMS or ecoflex.

Schedule

• • Have to start thinking about the clamp. 

  • Seal is almost finalized.

  • Had Kalmaz fill out the budget form thing and give Ian Richardson her index number.

Budget (list amount spent and amount remaining)

• • $1.19 for risk reduction seals

  • $12.28 for first flexible plug prototype.

Progress on Report and Webpage