156B Week 5

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

• Received ball screw and vibration mounts and have begun testing noise levels with hydrophone on current Pololu motor & vibration mounts. Completed power analysis and lubrication analysis. In the process of fabricating motor mounts.

Accomplishments from Previous Week

• Master CAD file created with different configurations

• Received parts from McMaster Carr

• Acquired hydrophone, did initial testing to assure it was working

• Matlab script for lubrication completed: lubrication of ball screw not an issue for lifetime of AUE deployment

• Gear ratios calculated & proper gears found

• Power analysis completed: 5 batteries has enough power needed for all motors 

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

• Receive motors for testing

• Receive gears for testing

• Complete draft of Final Report (Everyone)

• Test grommets: do they fit properly and help with vibration? (Hannah)

• Motor mounts (Hurby)

• Machine top plates (Myles)

• Machine ball screw (Devin)

• Acquire more batteries for testing: 9V for hydrophone, 6V for motors or C-cells (Hannah)

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

• Sponsor out of town, but been in touch with Paul (EE at Scripps), who has been assisting us with hydrophone data

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

• Try blue locktite for gears, better for testing than red locktite

• Motor gears should be metal, ballscrew gear should be nylon for best coefficient of friction. We ordered gears to match this

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

• All comments from students on 5/1 during proof of concept presentation:

  • Videos don't tend to work in PowerPoint on presentation day.

  • Good presentation! Well prepared.

  • Any way to make the hydrophone separate from the main metal structure?

  • Any concerns of water leakage or salt water issues?

  • If a photo is important to demonstrate, try to put some annotations.

  • Have you tried soft mounting the hydrophone on the existing AUE?

  • Problem description should have a picture to illustrate the project. 

  • Are you guys concerned about any deformation of the mount?

  • As it goes deeper, you will have an increasing hydrostatic pressure. Make sure you analyze it since you will need more power if it is at 100m.

  • Have you considered honeycomb structure to reduce the noise?

  • Put grommets in a fridge.

  • If there's room, maybe incorporate thermoelectric?

  • Have you looked at changing the metal that has less vibration?

  • Is it possible to change the frame so that it is more efficient?

  • Very cool. I have no suggestions.

Risks and Areas of Concern

• vibration mounts could interfere with gears meshing

• fitting necessary gear ratios in current volume control

Resources or Information Required but not Available

Schedule

• Describe upcoming milestone

• Updated Gantt chart uploaded

Budget (list amount spent and amount remaining)

• Spent: $359.26  

• Remaining: $2640.74

• Pending order from Micromo

• Pending order from 

Progress on Report and Webpage

• Continuing to edit Final Report for the draft due Friday