156B Week 8

Team 14 Progress Report

Winter 21 - Week 8

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

• In scope of Gantt Chart, in “Re-Design/Retesting Phase”

  • Iteration 2 of Stress Device is on the way

  • Strain device going through testing and refinement

Accomplishments from Previous Week

• Stress

  • Newest circuit components have been chosen and purchased (after approval by sponsor)

  • Newest form factor for device has been CADded and approved by sponsor

    • Edited components based on new circuit components, refined for better tolerancing and fits based off of results from the first iteration

    • Ordered and will arrive in time for testing next week

• Strain

  • Tested a ruler prototype over the weekend and saw promising results, all mechanical components seem to be working well

  • CAD of ruler device created and also approved by sponsor

    • Need to update with camera and hook component (which nerve will rest on)

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

• Stress (John and Ryan)

  • Prepare new circuit while waiting for 3D parts to come in

    • Tweak Arduino code to calibrate to 1kg

    • Get best sensitivity possible for FSR

  • Prepare rig for testing

    • Film rubber bands over gridlines in order to be able to generate stress-strain curve

  • Define stress models for design recommendations (how to get stress calculations from a sutured nerve)

• Strain (Archana and Tejas)

  • Update CAD model to include camera and hook element

  • Debug MATLAB software

    • As of now the software is unable to properly detect the circle markers during the ruler testing, so need to spend more time reading the documentation and modifying the code

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

• Sponsor Meeting held on Tuesday, February 23 (over Zoom)

  • Approved for plan for stress device as well as design for new iteration

    • Parts have been ordered in time for testing next week

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

• Professor talked about alternatives to FSRS such as piezoelectric sensors or bellows

  • Did some research, will continue to look into it to offer recommendations for future

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

• N/A (Progress report submitted before presentation day)

Risks and Areas of Concern

• Cadaver testing will need precise planning, very limited time to test with sample

Resources or Information Required but not Available

• May need a soldering iron, but to be determined

Schedule

• Thursday-Weekend:

  • Conduct preliminary design presentation

  • Finish 2nd Draft of report and website

  • Prepare testing-rig and setup for next rubberband testing

  • Prepare new circuit for stress device

• Monday-Wednesday:

  • Assemble stress device and conduct clearer rubberband tests

Budget (list amount spent and amount remaining)

• Amount Spent: $157.66 (will change next week)

• Amount Remaining: $2442.34

Progress on Report and Webpage

• 2nd Draft of Report will be submitted this Friday

• Webpage has been updated last Friday, will be further refined for this Friday

  • Will be sent to Sameer for review