Week 9

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

• Test have been conducted with final dish, beams and sample pieces

• Damping tape samples have  been obtained and used

• Temp enclosed chamber design has begun

Accomplishments from Previous Week

• Test running with ice, bending beam and samples have been run (All)

• LabView and DAQ have been connected to computer and produce results  (Bryan)

• Methods to produce flat ice (Daniel C. Paulo)

• Repaired various broken components of the motor (Daniel W.)

• Circuit has been created with strain gauge and amplifier and produces changes in voltage (Bryan Daniel W)

• Temperature enclosure in design stage (Daniel C.)

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

• Apply 3M damping tape to beam (Daniel W. Bryan) (Wed 3/7)

• Begin fabrication of temperature enclosure  (Paulo Daniel C.) (Wed 3/7)

• Test and calibrate the strain gauges bonded onto beams (Daniel W. Bryan) (in progress)

• Begin testing different materials (Daniel W., Bryan)(In progress)

• Twist and shield wires, and clean up wiring in circuit (Daniel C. Paulo)(Fri 3/9)

Sponsor Comments from Last Meeting and Actions Taken to Address these Comments

• Test a few different samples of materials at low speeds

• After a few issues we were able to test Teflon, a piece of an old ski and a piece of wood.  According to our results the Teflon had the lowest friction, the ski next and the piece of wood had considerably more friction.

• Work on fixing the vibrations

• We ordered and received the damping tape.  We applied it but still have yet to determine whether it has made any difference.

• By the end of the experiment relate back Tribology to the final conclusions. 

• We have plans to attempt to calculate the frictional coefficients and make some conclusions based on the nano-structure of the material versus the macroscopic scale of the ice roughness.

• Google more methods for smoothing the ice

• We looked up several methods including how Zambonie’s work.  It seems to apply the smallest layer of warm water is the best to create an even freeze.  We have been using a hot ragged dipped in water to smooth across which has been working better but needs improvement

Instructor Comments from Last Meeting and Actions Taken to Address these Comments

Can you laser cut thinner shim stock?

• No, because the metal reflects the laser

What about sample size issue?

• Sample size are 2 cm by 2 cm

Peer Comments

Are you conducting tests at room temperature? If so will the data collected usable if the sponsor is testing it at 5 C to -25 C?

•         The data will be used more as a comparative test than a straight coefficient of friction vs coefficient of friction. If test are ran in similar condition a comparison is obtained

Will the cold temperature affect the brittleness of the beam?

•         With the very little strain being measured, the beam won’t see enough strain to fracture due to brittleness. We also put the beam in the freezer and ran a test right after just to be sure and no difference was noticed.

Vibration may come from changing coefficient of friction

•         As the tester accelerates, the coefficient of friction lowers, so oscillations occur. Once the dish is fully accelerated, dampening causes the oscillations to reduce in magnitude, which allows us to get a good reading.

Heating from friction could melt ice

•         While this may be true, we are only running the tests one at a time and we have two dishes to cycle between, so we are constantly using/ refreezing dishes.

Could you use a longer beam to get more deflection?

•         A longer beam would result in more sensitivity to vibration and could also result in plastic deformation of the bending beam since it is so thin.

If you don’t have enough amplification, could you use a second amplifier before the data acquisition?

•        The instumentational amplifier that we are using contains 3 amplifiers inside of it that allows us to get different gains. More amplification would increase the amplification of both mechanical and electrical noise, which is something that we don’t want.

Run your data through a filter to clean it up

•        We could do this, but we are seeing very little electrical noise as it is. The electrical noise that we are seeing will be reduced once the circuit is optimized by twisting and shielding the wiring.

Possibly use an igloo cooler for the cold enclosure

•         We are actually looking into insulating the enclosure with Stryrofoam, which would essentially have the same effect.

Risks and Areas of Concern                           

• Ice deforming after a matter of rotations and creating more friction

• Strain gauge resolution being too small to measure differences of coefficient of friction sufficiently

• The amount of noise may overwhelming the signal

• Vibrations still being too large

Resources or Information Required but not Available

• None, currently.

Schedule

• Apply 3M damping tape to beam (Daniel W. Bryan) (Wed 3/7)

• Begin fabrication of temperature enclosure  (Paulo Daniel C.) (Wed 3/7)

• Test and calibrate the strain gauges bonded onto beams (Daniel W. Bryan) (in progress)

• Begin testing different materials (Daniel W., Bryan)(In progress)

• Twist and shield wires, and clean up wiring in circuit (Daniel C. Paulo)(Fri 3/9)

Budget (list amount spent and amount remaining)

• $20 – Shim stock

• $35 – Aluminum to fabricate new dishes

• 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.)

• Second draft of report finished on Friday (3/2)