Hi Bill,
If I remember correctly there is a "bug" in diadem 2010 with the chndurposnegcalc.
This is a copy of an email form Otmar at NI regarding the issue:
Hello David,
The ChnDurPosNegCalc is fixed in DIAdem 2011, so if you upgrade
you will have the corrected algorithm.
According to SAE the number of steps is set to 101 and the
durations are in one peak. If you with to change these parameters, you can do
this duration calculation over all peaks, and the number of duration points will
be the length of the input channel.
CallChnDurInjuryCalc("[1]/Time1","[1]/a_Head_hor","[1]/Time1","[1]/Speed","[1]/Time1","[1]/p_Airbag","in multiple
peaks","/PositivePortion1","/NegativePortion1","/PositiveLoadDuration1","/PositiveAmplitude1","/NegativeLoadDuration1","/NegativeAmplitude1","/PositiveInjury1","/NegativeInjury1") '...
X,Y,X1,Y1,X2,Y2,DurationType,E,E,E,E,E,E,E,E
CallChnDurInjuryCalc("[1]/Time1","[1]/a_Head_hor","[1]/Time1","[1]/Speed","[1]/Time1","[1]/p_Airbag","in one
peak","/PositivePortion2","/NegativePortion2","/PositiveLoadDuration2","/PositiveAmplitude2","/NegativeLoadDuration2","/NegativeAmplitude2","/PositiveInjury2","/NegativeInjury2") '...
X,Y,X1,Y1,X2,Y2,DurationType,E,E,E,E,E,E,E,E
The variable DurationType allows you to control
this through a Script.
For the FFC
calculations, the same duration algorithm is used in the "in one peak"mode.
With regards
to your Excel table suggestion, I have forwarded this to our R&D team. I
know that we have some gaps in the DIAdem tables, and this is something that we
are seriously looking into for a future release of DIAdem. I can't give you a
time line (other than it won't be in 2012) for this, but it is something we are
planning to add in a future release.
Please let me know if you have any additional questions,
Otmar
Basically one of the results overwrites itself. You should net 2 x's (duration) and 2y's (amplitude) but you only get one duration channel.
That being said there are ways around the problem.... you could absolute value the channel and use the chndurposcalc because it is in one peak for fx and fy. For the channels with positive and negative requirements FZ you need to use channel split at level and use the pos calc or neg calc.
