Mitutoyo SURFTEST SJ-410 - Rsk (JIS2001, ISO1997, ANSI, VDA, Free): Skewness (Degree of Asymmetry)

23. REFERENCE INFORMATION
No. 99MBB765A
23-21
23.5.8 Rsk (JIS2001, ISO1997, ANSI, VDA, Free): Skewness (Degree of asymmetry)
Rsk represents the degree of bias either in the upward or downward direction of an
amplitude distribution curve
*1
.
∑
=
⋅=
n
i
Yi
n
Rq
Rsk
1
3
3
11
*1: For an explanation of the amplitude distribution curve, refer to "23.5.38 ADC: Amplitude
Distribution Curve” (page 23-38).
Amplitude Distribution Curve
• For ANSI, Rsk is defined over the entire evaluation length.
Mean line
Measured profile
Amplitude Distribution Curve
Sk = 0
Sk < 0
(Abrasion resistance: large)
Sk > 0
(Abrasion resistance: small)