156A Week 9

We have held three meetings so far, two with our sponsor Dr. Kalmaz, and one design meeting among ourselves. 

Kickoff Meeting

We met with Dr. Kalmaz on Monday, March 6, 2017. At the kickoff meeting, she defined the problem she was having while performing a colonoscopy exam. As the tube is inserted into a person's anus, the colon collapses on itself and wants to be in a contracted state. With all these folds, polyps may be hiding in there that the doctor can't see. So the colonoscope has a tube to pump air or water inside the colon to expand it. That way, the doctor can perform a more comprehensive examination. The problem is that some people's anal sphincters can't seal around the colonoscope and so air or water would leak out and if it's water, it creates a giant mess and makes the procedure much longer than it should. Dr. Kalmaz wants the team to make her a small seal that can be inserted into the rectum and act as a sphincter. The device must be able to create a watertight or airtight seal around the colonoscope while allowing it to slide, and also seal/stay in place in the anal sphincter area. The device must be cheap and thus, disposable, and be able to be inserted after the colonoscope is inserted. 

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

• • During the Sunday design meeting, we talked about various methods of sealing the colonoscope, sealing the anal sphincter area, and materials. So far, everyone agrees on an arrow-shaped design. It would have a barb shape that would keep its position and not slip out as the colonoscope is being pushed in or out. The most variation was in the ways to seal the colonoscope. There were clamp designs, collar designs, snap fit designs, and different mechanisms of sealing the colonoscope, from inflatable balloons, to rubber disks.

• • Testing was also brought up during the discussion. We didn't know what pressure a person's colon would exert, and would want to know whether whatever sealing mechanism we come up with would work. An idea was brought up by putting the designed seal into the bottom of a large container of water, the rationale was that if the seal can withstand all that water pressure, it's going to work inside a human body. Another idea was to use the pressure rating from the air source of the colonoscope. Because the air source has to fight against a person's colon trying to contract and squeeze air out, the pressure rating has to be high enough to overcome that. If our seal can seal against that pressure, then it will for sure seal the air or water inside a person's colon.

Accomplishments from Previous Week

• • We finally got our project assigned after finishing the closed loop challenge.

  • scheduled meeting with Dr. Kalmaz on Monday 10am.

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

• • Present design ideas to Dr. Kalmaz (everyone)

  • finish risk reduction presentation (everyone)

Sponsor Comments from Last Meeting and Actions Taken to Address these Comments

• • Can talk to a guy in the gastronology department about 3D printing medical grade devices, since he's done it before.

  • She can get a representative from Olympus, the company that makes the colonoscope, to come in and talk about their colonoscope.

  • Emailed us specifications about the colonoscope.

  • Can get a pig for testing our device.

Instructor Comments from Last Meeting and Actions Taken to Address these Comments

• • Talk with Chris Cassidy ASAP about 3D printing flexible materials and reserving printer.

  • Talk with Professor Tolley to use his fancy resin printer.

Risks and Areas of Concern

• • Outer Seal (anal sphincter)

  • Inner Seal (colonoscope)

  • Movement of colonoscope 

  • Too much friction

  • how the clamping action would affect the seals.

  • one size fit all, need an average size.

  • no human testing. 

Resources or Information Required but not Available

• • Work space need to be assigned 

  • Instruction on 3D printer and printing material

  • Webpage access (got access in week 10).

Schedule

• • Describe upcoming milestone

  • Update Gantt chart.

  • Rush to get risk reduction presentation finished by Sunday.

  • Meet with Dr. Kalmaz on Thursday 2:00pm.

  • Use her input to continue designing.

Budget (list amount spent and amount remaining)

• • $0 spent so far

Progress on Report and Webpage

• • got access in week 10.