Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Fabricated 2nd and 3rd prototypes using a 3D printer
Did analysis to find the friction coeffient between two ABS surfaces
Came up with 4th prototype idea for our design, this time with a removable bottom that will attach to body as an adhesive
Tested ratchet and pawl idea. It works but we have problems with the top of the device staying on the top of the device
We used a straight rod through the center of our device to keep it on axis and prevent it from jumping off
Fabricated a hole through the bottom of our device
Accomplishments from Previous Week
Finished 2nd and 3rd prototype of device in Solidworks
3D printed 2nd and 3rd prototypes
performed testing for the Proof-of-Design presentation
We have a device that works for the most part, need to refine the movement of the top part, making sure it no longer wants to jump off
Goals for Next Week (list names after each item). Use specific and measurable objectives.
model 4th prototype in Solidworks (Peter)
3D print 4th prototype (Maverick)
Figure out a way to keep top part in place to prevent it from jumping off (Peter)
Understand fatigue stress (Dohwan)
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
(4/27/17-teleconference):
Showed Capillary our slides (incomplete)
Talked about our kinking issue with stylet and how top doesn’t choose to stay on
They say we have a robust looking housing unit
They notice the top of our device tends to want to pop off
They suggest using a screw with a sleve as a possible solution
brass tubing was also suggested
They still couldn't figure out how to get rid of bubbles in the ballistic gel that remain after melting
They noted we still need to figure out a way to remove the needle before the completion of the project
Brought up engineering standards and what standards are needed to comply with our device
suggest ISO standard: needle penetration force
suggest ANSI standard for drawings
FCC, ADA do not apply to our project
must think of biocompatibility of both adhesive and the device
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
(4/24/2017-in person)
need to fix future grammar and spelling mistakes in our progress report
suggested we purchase a spring of desired diameter to model our needle instead of using current music wire
springs would be uniformly made and thus be of higher quality than our hand made needles
Recommended to look up Shigley's Mechanical Engineering design book to try to figure our fatigue stress
Professor was concerned with the low resolution of the 3D printer for some of the small parts that we need to 3D print. Will have to machine it with Tom's help
Removal process of the needle needs to be solved
Professor wonders if 360 degrees of rotations is needed for our needle
Professor suggests using a bell jar to get rid of bubbles in the ballistic gel
Make sure we document both min and max skin tissue lengths
Start doing some analysis for next weeks presentation
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
How to remove needle after insertion of device?
How do we prevent kinking of needle at the exit hole at the bottom?
How to decompress spring after needle is engaged so you can wind it out of the body?
How do we keep the top of the device on without having it jump off each time?
How do we implement needle in our design? We have the force required, but that is all
Resources or Information Required but not Available
Client's catheter and stylet (Kennie believes that he can provide us by end of Week 5.)
Vacuum chamber to get rid of air bubbles inside the ballistic gel
Schedule
Describe upcoming milestone
05/01/2017: Concept Proof Presentation
05/04/2017: Testing Completion
05/11/2017: Design Revision Completion
Update Gantt chart.
Completed
Budget (list amount spent and amount remaining)
Budget:$700
spent: $150.10
Remaining: $549.90
Progress on Report and Webpage
Progress Report: In progress
Gantt Chart: Updated