Here is code I used to process force data for my swept foil experiments and for forced vibration experiments.

Feel free to modify for your own processing needs/chuckle at my poor coding abilities.

Overview of what you need to do to process force data:

Load in the two files you obtained 1)*.lvm contains force data 2) *.txt contains position data

Calculate the inertia forces. You can either do this by repeating your experiments in air (but that requires draining and refilling the tank), or using F_inertia = (mass of everything below the force sensor)* (acceleration), where acceleration is calculated using the double derivative of position (from the *.txt file). This file is saved in hex format, so you need to convert it to a read-able form.

Calculate the total forces. Do this by multiplying the 6x6 calibration matrix (and scaling factors) to the 6 columns of force data (they should be the first 6 of the 9 columns saved, if you used our standard LabView program to collect data). Apply an appropriate filter. 

Calculate the hydrodynamic forces. F_hydro is the remaining component of F_total after you remove F_inertia.

Calculate non-dimensional coefficients as desired. Use the length of the submerged span in the calculation.

  File Modified
ZIP Archive ForcedVibProcessing (04_24_11).zip Heather's Whisker Experiment Mar 14, 2012 00:20 by beem@mit.edu
File Foil_Force_Processing.m Heather's Sweepback Experiment Mar 14, 2012 00:20 by beem@mit.edu
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