1. A 3D Scanning System for Fabric Fuzziness and Pilling Evaluations
Bugao Xu and Ming Yao
The University of Texas at Austin
January 2005

2. 3D Laser Scanning System
Goal
to acquire the surface profile of a fabric and to characterize the surface roughness.
Setup
Profile sensor: 10um
2-axis stage: 0.5 um/step
A/D board: 12 bits

3. Hardware
Dimension: 8 x 8 x 6 inches

4. Software

5. Samples
Five knitted fabric (interlock, dark blue) were washed and dried different cycles.
F5: no fuzz
F4: low
F3: medium
F2: high (a few pills)
F1: severe ( a lot pills)

6. Procedures Scan the sample Level the surface Set the central plane
Select the offset plane
Calculate surface parameters

7. Scanning
Profiles, 1x1 in2
Surface, 200 DPI
Surface, 400 DPI

8. Leveling (B-spline Approximation)
u and v: two parameters
Ni,q(v) and Nj,p: basis functions
p and q: degrees
{Pi,j|0<i<m, 0<j<n}: control points

9. Leveling
Scanned Surface
B-spline Fit Plane
Leveled Surface

10. Offset Plane Central Plane u=0 um Offset Plane u=0.25um

11. Surface Roughness (ANSI/ASME B46.1-1985)
Roughness Average Ra Root-Mean-Square Roughness Rq Skewness Rs
Central Line yi

12. Skewness

13. Surface Roughness (ANSI/ASME B46.1-1985)
Ten-point Height Rz:

14. Surface Roughness (ANSI/ASME B46.1-1985)
Bearing Length Ratio tp: Mean Spacing Rsm:

15. Surface Roughness
Peak Count Np: Peak Size Average Sa: Peak Height Average Ha:

16. F5

17. F4

18. F3

19. F2

20. F1

21. Pilling

22. Results

23. Results

24. Results F1 F2 F3 F4 F5 F6 Ra
0.287
0.139
0.123
0.101
0.086
0.092 Rq
0.365
0.181
0.158
0.127
0.110
0.140 Rz
1.257
0.613
0.573
0.383
0.334
0.690 Rs
0.518
0.455
0.237
0.005
-0.001
2.270 tp
0.259
0.061
0.056
0.017
0.008
0.019 Np
0.446
0.481
0.535
0.277
0.184
0.047 Sa
0.507
0.154
0.109
0.089
0.067
0.248 Ha
0.511
0.368
0.335
0.304
0.296
0.714

25. Conclusions
The selected surface parameters can effectively differentiate the level of fabric fuzziness/pilling.
It provides the characteristic information about fuzz and pills.
It is independent of fabric structure, color and orientation.
The scanning is a slow process.