156B Week 5

Team 14 Progress Report

Winter 21 - Week 5

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

• In testing phase for both stress and strain

  • Stress

    • 3D printed parts received-minor tolerancing issues

    • Continuously calibrating the FSR

  • Strain

    • Testing different softwares and markers using rubber bands

Accomplishments from Previous Week

• Stress

  • Calibration for FSR dissected (John and Ryan)

    • Resistance - Force graph from Pololu specs used to edit Arduino Code

    • Able to get values around 1N, other ranges not as accurate

  • Form factor assembly (John)

    • 3D printed parts arrived

    • Some sanding required for better tolerance

    • Form factor put together, FSR not yet integrated

• Strain

  • Tested different marker (sharpie dots, plastic spheres, pieces of) configurations on rubber band to use as input for Digital Image Correlation (DIC) software (Tejas )

  • Tested different Digital Image Correlation (DIC) Softwares (Tejas and Archana)

  • Found Deformation values of rubber band through a DIC software (Archana)

• Overall:

  • Progress on Proof of Concept Presentation

  • Progress on First Rough Draft

  • Progress on Website

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

• Stress (John and Ryan)

  • Calibrate FSR to acceptable values

  • Integrate FSR into form factor

    • Test on rubber bands

    • Find way to define area of rubber bands

• Strain

  • Finalise the final software/code to use to measure strain and deformation (Tejas and Archana)

  • Test different configurations of rubber band under different loading conditions (dynamic, and loadings from different angles) (Tejas and Archana)

  • Shortlist optimum marker sizes and shapes to use for DIC (Tejas and Archana)

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 on February 2 (via Zoom)

  • Parts arrived, said it was okay to use whatever we need to make it work at this stage (glue, duct tape, etc.)

    • Will be sanding parts to fit better

  • For proof of concept, asked to calculate strain from the obtained deformation values

  • Suggested to look at the backend code in DIC softwares to understand which variables are required and how they are used. He asked us to do this so we can troubleshoot and modify the code according to our need (Some DIC softwares are just matlab codes)

    • Will both be done as week progresses

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

• Scheduled Meeting on January 28 (via Zoom)

  • Clarified “90 degree” orientation

    • Will be taken into consideration for next iteration

  • Reminded that device in production would not be 3D printed

    • No need to keep finding external 3D printing services for price comparisons, can do next through the school

  • Advised to look at free software given through the school, Darren also offered to request for any additional software that the school does not currently offer

    • Still working on current DIC software, if unsuccessful, will contact Darren

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

• 3D Printing

  • 3D Print lead/turnaround time from external source not desirable

  • Will go through school for next iteration

• Strain

  • Unable to specifically identify the markers on the rubber band in existing DIC software. The current softwares automatically creates a mesh on the object. (Knowing the change in apparent size of the marker is necessary to calculate planar movement).

    • Difficulty in understanding the limitations of the software and unable to modify them to our needs

Resources or Information Required but not Available

• Professional version of Digital Imaging Software

  • Dependent on eventual decision for use/extension of use (on free version right now)

  • Training for the use of DIC software for our application

Schedule

• Thursday: Proof of concept presentation

• Friday-Weekend: Continuous testing (of different DIC softwares for strain)

• Rest of Week: Continuous testing (of different configurations on one DIC software)

Budget (list amount spent and amount remaining)

• Amount Spent: $157.66

• Amount Remaining: $2442.34

Progress on Report and Webpage

• Report:

  • First Rough Draft in progress, will be uploaded by Friday

• Webpage

  • Web Page being updated, first draft ready by Friday