Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Test run with Teflon on rotating ice dish has been performed
Nuts have been glued into the dish as temporary stops to prevent ice from rotating
Waiting on Mike Watkins to return for help with strain gauge attachment to beams
Bending beam tests on hard drive tester being set up
Accomplishments from Previous Week
Obtained amplifier, DAQ, and strain gauges (Bryan Daniel W.)
Glued some nuts and bolts into dish to prevent ice from rotating (Daniel C. Paulo)
Preliminary tests of Teflon sample on dish with ice (Paulo)
Researched Damping Materials from 3M (Daniel W.)
CAD drawing of hard drive tester with bending beam clamp (Daniel W.)
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Create new dish which can prevent ice from slipping (Daniel C. Paulo)
Modify 170 LabVIEW VI (Bryan )
Strain gauges bonded onto two beams (Daniel W Bryan )
Tests with actual sample on dish with ice (Paulo Daniel C.)
Get 3M damping tape (Daniel W)
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments
Purchase Damping Tape.
We are purchasing the tape currently.
Bond Strain Gauges on and get some data
We have been waiting for Mike Watson to return to bond on the strain gauges and have therefore not been able to get data yet, hopefully we can have them bonded by the end of the week
Obtain LabVIEW
Downloaded the free student trial and are getting the VI for the bending beam MAE 170 lab
Instructor Comments from Last Meeting and Actions Taken to Address these Comments
Cost of power supply vs. MAE 3 power supply why is it so expensive?
The power supply we are using for the 5V supply is $335. The 60 V power supply cost $3,555.00. The hard drive tester is custom but a guess would be $5000- $10000 ( all of these are recycled machines). They have very small changes in resistance and voltage resolution. Very fast response time very little noise.
Fix Optical Sensor
Tried obtaining one for free, haven’t found one yet will look in Professor Talke’s lab before purchasing one
Consider the effect of airflow on bending beam
We think that the vibrational tape may help prevent this from being a problem
Protect cleanliness of sample methods to do this?
Spoke to Professor Jin and he said not to touch the samples with our hands but he is not sure if we can clean them with anything and must ask his Postdoc students
TALK TO STEVE ROBERTS ABOUT AMPLIFIER
We spoke to him and Mike Watson who directed checked us out an AD 524 amplifier Mike mentioned that most likely a gain of 100 is used and he will help us wire it once the strain gauges are attached to the bending beam
Learn about damping materials-can you just paint it on?
There are paints and sprays but it is hard to maintain a consistent coat so the tape will be used instead
How do we get the strain gauge attached? talk to Vishay.
There are adhesives you can apply Vishay has several M Bond 200 is most commonly used. Mike Watson has the materials and is willing to bond them on for us.
One temperature on each gauge may be a different temperature.
The full gauge panel since they are all on one gauge are resistant to temperature changes if one were on top of the beam and one were on bottom.
Present to Mike before presentation.
Met with Mike on Tuesday he helped us with our content for the presentation.
Do we need to adjust for Poisson’s elongation?
The Full bridge gauge we have compensates for this by having two gauges in poisson elongation
Do beam bending and strain integrate with strain gauge spec sheet?
With a very thin beam it will create enough strain and possibly with the thicker beams if the friction is higher than we conservatively calculated. The gauge factor could ideally be a little larger but the preliminary tests should make this clear.
Any electrical noise out there you will also be amplifying?
The noise from the power outlets, the wires, hopefully the twisted, wires will decrease that. The strain gauge and amplifier should cut down some of the noise
Leads to strain gauge should be twisted and shielded and the shortest distance between the op amp?
We spoke to Mike Watson about this and he assured us once we bond on the strain gauges he will help us out but the type of wire depends on the size of the soldering pads on the strain gauges
Wants plots and video and signal to noise ratio?
Unfortunately since we haven’t been able to attach the strain gauges we have not been able to get actual data, but by the end of this week or sometime mid next week we will have data.
Risks and Areas of Concern
Ice chipping out when samples are placed on it while spinning
Ice slipping on the bottom surface of the dish
The amount of noise may overwhelm the signal
Resources or Information Required but not Available
We would like to use a large freezer to test the hard drive tester which was provided. We have no knowledge about the tester because it is so old and would like to see its performance at low temperatures
Schedule
Obtain and attach strain gauges by the end of the week 2/17 (Bryan, Daniel W.)
Make modified dishes which will allow for the ice to rotate (Daniel C. Paulo)
Run beam tests with various damping materials once new dishes have been fabricated (Daniel C. Paulo)
Test beams with strain gauges and determine the most ideal size to use (Bryan, Daniel W.)
Brainstorm modification idea of the Hard Drive Tester (All)
Documenting each activities for use in final report (All)
Budget (list amount spent and amount remaining)
$20 – Shim stock
$80-$100- 3m 434 Vibration Damping Tape
Now have a $500 budget but still need to run purchases by Professor Talke
Progress on Report and Webpage
Webpage has all individual component reports
Webpage has weekly progress reports and all the presentations
CAD drawing on front page
Add actual pictures, video and more updated info (Paulo Daniel C.)
Report – keeping data and pictures of our preliminary tests for use in the report (Bryan and Daniel W.)