156B Week 9

Week 8 Progress Report

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

• • “Final” Design Completed (Final in quotes because we have completed our final designs but will be handing off the project for further work to the next 156B team)

  • Additional testing conducted

  • Report and Web Page 90% Completed

Accomplishments from Previous Week

• • 3D printed rope connection pieces (the pieces that will attach to the top and bottom plates, and will anchor the ropes used to keep the reinforcement rings from rotating out of plane)

  • Fabricated an extra ring segment using carbon fiber sleeves for new 3 point bending test

  • Tested full device assembly (using both reinforcement ring + waistband belt)

    • Hit 23.5 mmHg maximum negative pressure

    • Maintained negative pressure above 10 mmHg for one minute

  • Made substantial progress on the final report and web page. 

  • Abaqus FEA analysis for 2 layer carbon fiber ring

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

• • Finish project poster (Jen, Jackie, Brian, Geoffrey)

  • Finish Final Report (Jen, Jackie, Brian, Geoffrey)

  • Finish Final Web Page (Jen, Jackie, Brian, Geoffrey)

  • Conduct 3 point bending test with new ring segment (Jen, Jackie, Brian)

  • Fabricate and test two ring segment design (ran out of insulation foam this past week to make the test ring segment for 3 point bending test) (Jen and Jackie)

  • Try to get hardware for wire outlet design (Geoffrey)

  • Final Design Review Presentation with sponsor (Jen, Jackie, Brian, Geoffrey)

  • Meet with incoming 156B group to explain this quarter’s progress, design recommendations, and hand-off (Jen, Jackie, Brian, Geoffrey)

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

• • Should set up a time to meet with new 156B group - emailed new group members with a poll to determine when everyone is free to meet up

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

• • Consider elastic stability (Roark’s Formulas for Stress and Strain) (suggested during email correspondence) - used recommended text to conduct a simple elastic stability analysis shown in Appendix of Preliminary Design Review Presentation and Final Report. We determined that elastic instability would not likely be the mode of failure for the carbon fiber since we observed very brittle fracture failure during the three point bending test. We included the analysis in appendix for thoroughness but was not included in the main discussion of our device. 

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

• • Explain analysis portions of presentation more thoroughly - we consider this a bit difficult to do because of the time constraint and the amount of other information that needed to be covered as specified by the presentation guidelines. Some feedback said we had good analysis though.

  • Both that our presentation skills were excellent and that they needed improvement (presentation feedback was pretty split on this topic. Not sure which we should believe). 

Risks and Areas of Concern

• • N/A

Resources or Information Required but not Available

• • N/A

Schedule

• • On schedule with most tests planned. 

  • Two segment ring design pushed back due to running out of insulation foam 

Budget (list amount spent and amount remaining)

• • Week 9 Beginning Balance: $ 2,185.02

  • Amount spent: $ 0.00

Progress on Report and Webpage

• • All Final Report Sections mostly filled out. Just need to include results of our final tests. Need to finalize figures, figure numbers, and captions.

  • Webpage mostly completed. Need to shoot video for the web page. Need to sort out formatting issues with Google Sites.