156B Week 4

Week 4 Progress Report

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

• • Revised design to three plausible configurations: wire pulling, oil filled linear actuation, electromagnetic actuation

  • Bought additional motors and sensors needed for designs

  • Completed third CAD design of housing

  • Running on a full tank

Accomplishments from Previous Week

• • Completed CAD design of housing setup (Ciara)

  • Printed then updated prototype for tentacles (Michael)

  • Selected motors for steering mechanism (Ciara)

  • Bought motors and electronic components (Ciara and Damian)

  • Printed preliminary fin ray and updated prototype (Michael and Damian)

  • Made contacts with companies for buying gears and bladders (Damian)

  • Created solution to linear actuation issues (Damian and Trevor)

  • Re-designed solution based on previously discussed performance concerns (Everyone)

  • Tested pump force feasibility for mobility (Trevor)

  • Design/CAD for Miga actuators mounting and oil reservoir (Michael)

  • Got fish tank (Damian)

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

• • Print housings for testing of both designs (Ciara and Damian)

  • Make mount for actuator for testing (Damian)

  • Get lamenated sheet material

  • Print ABS Fin Ray (Michael)

  • Print Miga Motor oil resevoir (Michael)

  • Setup Raspberry Pi and test actuators (Everyone)

  • Acquire power supply for non-autonomous testing (Trevor)

  • Test aquatic pumps as steering mechanism (Trevor)

  • Buy gears for steering mechanism (Ciara)

  • Eliminate one design for actuation ()

  • Finish ordering things for testing like magnets, electromagnets, dome, battery, (Damian)

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

• • Attempt linear actuation solution (4/13/16, via email)

    • Designed practical solution given this constraint

  • Likes the idea of a central piston and will pay for piston machining (4/13/16, via email)

    • Avoid dynamic sealing of piston because of wear

  • Does not like SMA in tentacles (4/12/16 in person)

    • Look into wire actuation that is not SMA

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

• • Finalize design based on ideas discussed in the second meeting

    • Will test designs this week and continue with the most plausible solution

  • Buoyancy issues

    • Shoot for neutrally buoyant and adjustable weights for buoyancy

  • Compressive force on bellows or diaphragm

    • Got advice to use an oil bag to equalize pressures on both sides for any depth

  • Gap for attractive magnetic coupling is infeasible

    • Look into shim stock and double repulsion

  • Lot on our plate

    • Bought stuff to test and start eliminating things to move forward

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

• • Kazu - Could try chemical reaction for actuation or compressed air though not sure how long it would last you (4/15/2016 in person)

  • Riley - Why not use a bag instead of tentacles? (4/11/2016 in person)

  • Conner - Expressed interest in how we were going to control? (4/15/2016 in person)

Risks and Areas of Concern

• • No newly discovered risks

Resources or Information Required but not Available

• • None

Schedule

• • Upcoming Milestones:

    • Design Tests

    • Create Proof of Concept

Budget (list amount spent and amount remaining)

• • Total Spent: $366 Total Remaining: $2,144

Progress on Report and Webpage

• • Updated report with revised sections

  • Updated Gantt chart