MTS Multipurpose Elite - Manual (Page 243)

Returns
The function returns the index associated with the end of the Yield Point Elongation region.
Syntax
YpeEndIndexByIncreasingLoad(ForceArray, YPEStartIndex, Tolerance)
Parameters
ForceArray - The force array used to determine end of the Yield Point Elongation region.
YPEStartIndex - The index associated with the start of the Yield Point Elongation region.
Tolerance - The percentage difference in force at the YPE start index used to detect the YPE end index.
Unit Class
Integer
Example
YPEStartIndex = 100
Tolerance = 1 %
Force at YPE Start = 1000 N
Force Tolerance = 1000 N * 1% = 10 N
Assuming the peak was located at index 200, the algorithm starts at index 200 and go towards index 100.
At each point, the force is compared to the force at YPE Start. When the Force of the currently compared
points is within 10 N of the YPE Start value, the YPE end index is located.
Algorithm
1. Find the peak load index after the YPE Start index.
2. Starting at this point search backwards down the curve until the load value is within the specified
tolerance of the load at the YPE Start index.
3. Report the index where this criterion is met as the YPE End index.
YpeEndIndexByTwoSlopes
The YpeEndIndexByTwoSlopes function located the end of the Yield Point Elongation region by finding
the point of intersection of the maximum slope line and the zero slope line (both after the YPE Start index).
Returns
The function returns the index associated with the end of the Yield Point Elongation region.
Syntax
YpeEndIndexByTwoSlopes(ForceArray, DisplacementArray, YPEStartIndex, PeakTolerance,
ZeroSlopeSegmentLength, MaxSlopeSegmentLength)
MTS TestSuite | 243
Working with Variables