P17082 Biomechanical Elbow Model Build and Test Prep Maria Romero-Creel, Shannon Keenan, Chris Harley, Amanda Cook
Agenda New Issues / Problem Review / Design Updates Accomplishments since last review Parts Status BOM Build Status Testing Status and Results Action Items Schedule Review Miscellaneous Deliverables
Overview Team Vision The plan for this phase was to regroup after the break and evaluate overall project status, goals, and revisit any outstanding action items from the detailed design review and gate review. These action items mainly concerned updating documentation and continuing progress on a prototype. Completed Goals: All necessary documentation was updated Problem tracking was introduced Initial plans for a truss structure were used Possible design competitions were investigated. Pending Goals: Completed prototype and test plan data – Due to unlikely difficulties with 3D printing that should not be a regular concern moving forward.
New Issues and Design Updates No new issues have been identified so far. Design Updates No updated have been done on the designs of the bones. Preliminary design of truss was completed.
Parts Status and BOM Parts Status: All missing parts from McMaster Carr have been ordered and are scheduled to arrive next week. Bones are in the process of being printed.
Test Plans – Engineering Requirements Overview
Test Plans ER1,2,3 – Static Force of Muscle A, B, and C. Test - Attach load cell to break in muscle string, hang 250g mass from hand hook, wait for arm to lower under the weight and settle, then get read out from Capstone. Validity- Force achieved at rest must match accepted anatomical value. ER4 – Angles at each position Test - With each muscle attached and load cells strung, and the goniometer attached and reading out to Capstone, the arm is bent at the elbow and moved through the available range of motion. Validity- readout must show that the arm can move from approximately 0o and 180o. ER5 – Max Load Test -Hang a load of 500g from the hand hook while holding the lower arm up to the upper arm so that the angle of the elbow is approximately 0o. release the lower arm and allow the weight and lower arm to fall. Validity- The arm must be able to fall and stop while still holding the weight, staying upright and stable and produce steady force and angle change graphs / tables through Capstone. There should be no bending or material failure in a valid case, and the entire base must still be resting on the tabletop.
Test Plans ER6- Muscle Attachment Position Test - With load cells in place, no weights, and the lower arm resting so that the angle of the elbow is approximately 90o, measure the angles of the muscles with the bones and the distance of the muscle attachment to the bones. Validity – Both values must be within ±5%of the average adult. ER7,8 – Deviation and Possible Positions Test - Set the model in each possible position with the 250g weight. For each position (supinated wrist, pronated wrist, flexed elbow), allow the device to sit, with no contact or extra support from an outside object for 1 minute, measure deviation. Validity – The position set by the user must not deviate by more than ±1cm during the wait period. ER9- Time Required for Assembly Test - Begin with an unassembled device. Start a timer and begin assembly, including the addition of base structure strings, load cells, goniometer, and arm straps. Include all hardware cables necessary for data acquisition (load cells, goniometer). Validity – The full assembly takes approximately 20 minutes or less to assemble and can support a 250g weight from the hand hook upon completion.
Action Completion from Gate Review Action Item from last review Update BOM-Amanda & Maria-100% Review Engineering Requirements - All-100% Print Full Set of High Density Bones - All - 50% Build Truss Structure - Amanda & Chris- 90% Begin Considerations for Paper & Poster - All - 50% Update Schedule (including Casting Option) - Shannon - 100% Research Possible Competitions - All - 90% Consider Current Problems & Plans- All - 100% Apply Test Plans to Prototype - All - 0% Make Any Manual Changes to Bones - All - 0% Purchasing - Amanda - 90%
Action Items Action Items Moving Forward No Casting: Finish Printing Bones - All Assemble Prototype w/ subsystems - All Test Prototype - All Document Truss Construction - Chris & Amanda Track Any Problems - Shannon Make Manual Edits to Bones - All With Casting: Prep for Casting Molds – All Upcoming Deadlines: Casting Decision Week 3 12 model deliverable decision Week 5
Plans & Schedule
Individual Three Week Plan Amanda: Lead purchasing and budget plans/requests Work with the team to print the remaining 3-D bones Actively participate in the building of the truss structure Test the subsystems (bones, truss structure, and software)Continue to consult with SME for physiological accuracy of the model Shannon: Start & maintain problem tracking Help with managing test plans & results Begin tracking design competitions and upcoming dates Assist with construction & printing Manage timeline on upcoming decisions: Casting & 12 models
Individual Three Week Plan Chris: Get final prints of all bones (3- 8) hours Any solidworks modeling/ drawing updates Test plan finalization (6-8) hours Begin building the first unit (5) Begin testing of the first unit (6 hours) Maria: Consult SMEs and Customer and decide on casting vs. 3D printing. Participate in printing and testing of design. Participate in building and assessing feasibility of model. Consult SMEs and help ensure physiological accuracy of model. Work on manual for building, testing, and using the completed model.
Miscellaneous Deliverables ASME IAM3D Challenge: (April 21) https://www.asme.org/events/competitions/iam3d-challenge IEEE Design Competition: (June 1) www.ieee.org/membership_services/membership/students/awards/eng_medicine_undergrad_design.html BMES Design Competition: (No available date yet) www.bmes.org/4DCGI/cms/review.html?Action=CMS_Document&DocID=207&MenuKey=students (this is for 2016 but hopefully maybe there's a 2017 one?)
Questions or Suggestions?