Averaging of Multiple Graphs Into One Graph

[GordonS]

Hi Everyone,

I have a unique situation/problem that I would like to see if DIAdem can solve natively. I am currently using DIAdem to display engine combustion pressure traces in a MDF4 format. The traces are one continuous data stream (not broken up) and are indexed at a 1 deg crank angle increment. Since one complete combustion cycle is two revolutions of a engine crank, the pressure traces start out at -360 degrees and it increments upward to +359 degrees before switching back over to -360 degrees, with 0 Degrees corresponding to Top Dead Center for the pressure trace/piston position. The pressure trances are also saved with a "continuous indexing" option, starting at 1 and continuing untill the data acquisition stops. I would like to average about 30 cycles to get one averaged pressure trace. Now I could export the data and average it via Excel, but I would like to see if DIAdem can do this natively without the need to exports. Can DIAdem do this?

Thank You,

Gordon

[Brad_Turpin]

Hi Gordon,

I think your best bet would be to break up that one Pressure channel that has data for N cycles into N Pressure channels that have data for 1 cycle.  This would have the advantage that you could overlay all the cycles on a graph a view them.  The "Average Channels) ANALYSIS function would also give you an easy way to perform the averaging you want.  So this boils down to finding a reasonable way to split you 1 channel into N channels.  Is there a constant number of data points for each cycle?  Could you post or email (brad.turpin@ni.com) a sample data set for me to play with?

Brad Turpin

DIAdem Product Support Engineer

National Instruments