Fly Ergometer data acquisition and Analysis

I've only done Acquistion on a PC, but the analysis works fine on PCs, Macs and Linux.

Acquisition: Download the PC software layout for Data acquistion, to calculate the vertical and horizontal components from the 4 quadrant inputs:
This assumes that you have a National Instruments A/D card (USB 6008 is fine, though it can be rather noisy). Versions for other manufacturer's A/D cards by arrangement.

Replay: Dasyview software for PCs, Macs and Linux to replay the data recorded in Dasylab or Labview. You should get a trace like this, showing three stimuli on the top trace, three downwars resposnes on the second trace and three horizontal respoinses on the bottom trace:

Image of jump trace

Analysis: to start we need to create the best settings: Mine are:
  1. Click once on the stimulus trace to highlight it. Set the threeshold about halfway up your stimulus by using the Process | Set threshold menu
  2. Set the duration for the overlays, to 0.35s, using Process | Set Duration of overlay 
  3. Set the pretrigger to 10%  using Process | Set Pretrigger for overlay 
  4. Download my Excel / Open Office spreadsheet FLY_JUMP_HORIZ.xlt (old version:  fly_jump.xlt) to calculate the peak beam deflection and angle of take off during the jump.
Then we click on the stimulus trace, use Process | Overlay to get a picture like this,
Overlaid Image Trace
You can see that the vertical trace is laid out regularly, and there is more variability in the horizontal trace. Click on the vertical trace to select it, and choose Channels | Fit trace, and you will get output in the lower, log window. Now click on the horizontal trace to select it, and choose Channels | Fit trace, and you will get more output in the lower, log window. 

Click in the log window,  right click [on a one mouse-button Mac, CMD + click] and choose Select All,  right click again and choose Copy, and paste it into the Excel spreadsheet. My output looks like this

Log file
Report on : 7_5_15h57m_p_p_o.DDF
Path : Q:\jump\round1\CS
Sampling began at Fri May 07 15:57:19 2010
...
Ver     0     94.64     106.2     4.296     0.0084     0.1111
Ver     1     94.21     107.4     22.29     0.0102     0.1081
Ver     2     86.45     95.47     21.27     0.0096     0.1129
Ver     average     91.8     103     15.95     0.0094     0.1107
Hor     0     85.75     95.49     65.82     0.015     0.1009
Hor     1     113.7     114.9     85.5     0.0144     0.0139
Hor     2     97.21     98.49     81.4     0.0013     0.0007
Hor     average     98.9     103     77.57     0.01023     0.0385

My Excel sheet looks like this, as I have a calibration factor of 2.4 between mV and mm, from the "Calib" page of the spreadsheet. It automatically calculates the best jump for each fly and the mean / SD / SE for all the flies (up to 20 in Excel)

Screendump of excel shhet


All downloads at your own risk.


Chris Elliott, updated May 2011