Reliability of Cotton Fiber Length Distributions Measured By Dual-Beard Fibrography and Advanced Fiber Information System

Fiber length distribution (FLD) is one of the fundamental properties of cotton fibers, which determines cotton length attributes, such as upper half mean length (UHML) and short fiber content (SFC), and thus fiber processability and yarn properties. For decades, the Advanced Fiber Information System (AFIS) has been the only instrument that can provide explicit FLD measurements. However, the reliability of AFIS’s FLD has not been carefully inspected although important issues (e.g., excessive short fiber contents and super long fibers) were raised before. Recently, dual-beard fibrography (DBF) emerges as a novel approach designated for direct FLD measurements and provides non-destructive testing that enables repeatability analysis on FLDs.  In this paper, we intend to conduct a thorough repeatability study on DBF with different testing scenarios to prove that DBF is a reliable method for FLD measurements, and then use DBF’s FLDs to examine AFIS’s FLDs to develop a better understanding on the existing problems associated with AFIS. The testing scenarios with DBF included multiple tests with one dual-beard sample at the same scanning position, the same sample at different positions, different sample reps by one scanner, and one sample rep by different scanners. The comparison tests between DBF and AFIS were performed on 17 selected cotton samples with a wide range of length uniformity. It was found that DBF’s FLDs are highly repeatable on one scanner (r>0.99, P=0 and SSE<0.14) and highly reproduceable between two scanners (r>0.99, P=0 and SSE<0.51).  It was demonstrated that the FLDs produced by AFIS and DBF with the same samples are highly correlated (r>0.91, P<5.19e-16), even if AFIS’s FLDs have consistently higher frequencies in the short fiber range (0 to 12.7 mm) and in a super-long fiber range (40 to 60 mm) unrealistic to US upland cotton.