Mean-Value Method of Lateral Force Calibration
description
Transcript of Mean-Value Method of Lateral Force Calibration
![Page 1: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/1.jpg)
MEAN-VALUE METHOD OF LATERAL FORCE CALIBRATION
A Major Qualifying ProjectByDerek Eggiman
![Page 2: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/2.jpg)
INTRODUCTION
![Page 3: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/3.jpg)
ACKNOWLEDGMENTS We would like to
thank Sigma-Xi for generously funding this project.
We would also like to thank Professor Nancy Burnham and Dr. Deli Liu.
![Page 4: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/4.jpg)
ATOMIC FORCE MICROSCOPE
Focused laser is reflected off cantilever.
Changes in cantilever orientation result in a change of laser position
Laser position is detected by the photo diode.
Cantilever position is interpolated from photo diode signal.
![Page 5: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/5.jpg)
CURRENT PROBLEMS IN LFM CALIBRATION Many studies assume a functional form
for friction, f=μ(N+A). Other methods calibrate as a function
of load. Repeated scans Excess tip wear.
Other methods require special equipment or are far to complicated and time consuming.
Want quick, in-situ method.
![Page 6: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/6.jpg)
METHODOLOGY Equilibrium
equations depend on direction of motion (Vx) and angle (θ).
Taking the average value of scans in opposite directions over the same surface results in cancelations.
Flat-avg= Floadtan(θ) or Vlat-avg= αFloadtan(θ)
![Page 7: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/7.jpg)
RESULTS & DISCUSSION
![Page 8: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/8.jpg)
SAMPLES:TESTED Piano wire Steel rod Solder spheres 1.588 mm diameter
Si3N4 ball bearings
http://www.satotekkou.co.jp/en/product/img/ceramic-p04.jpg
![Page 9: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/9.jpg)
SINGLE SCAN: TOPOGRAPHY & LFM
![Page 10: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/10.jpg)
SINGLE SCAN: RE-PLOT
![Page 11: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/11.jpg)
EXPERIMENTAL DIFFICULTIES Finding a sufficiently
smooth surface Lack of lateral force
sensitivity Crosstalk of lateral
and normal force signals
![Page 12: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/12.jpg)
CROSSTALK
![Page 13: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/13.jpg)
FULL SCAN MEAN-VALUE ANALYSIS Obtained by taking a complete image of
256X256 data points in a 27 X 27 (μm) scan range.
Then taking the mean value along the y axis and using this data to perform our analysis.
Plotted the mean value of: Topography (μm) LFM Forward LFM Reverse
![Page 14: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/14.jpg)
FULL SCAN: TOPOGRAPHY
![Page 15: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/15.jpg)
FULL SCAN: LFM
![Page 16: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/16.jpg)
FULL SCAN: RE-PLOT
![Page 17: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/17.jpg)
CONCLUSIONS Mean value of 256 X 256 point scan
shows high degree of linearity. R2=0.961.
Successfully derived proof of concept. Work will be continued by Saonti
Chakraborty and published in a peer reviewed journal.
![Page 18: Mean-Value Method of Lateral Force Calibration](https://reader035.fdocuments.us/reader035/viewer/2022062811/56815fd3550346895dced037/html5/thumbnails/18.jpg)
QUESTIONS?
http://www.phdcomics.com/comics/archive.php?comicid=771