Apparel Fit Based on Viewing of 3D Virtual Models and Live Models A DISSERTATION ...

158 Pages·2009·10.24 MB·English

Apparel Fit Based on Viewing of 3D Virtual Models and Live Models

A DISSERTATION
SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL
OF THE UNIVERSITY OF MINNESOTA
BY

Dong-Eun Kim

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

Karen LaBat, Adviser

June 2009
© Dong-Eun Kim, 2009
Acknowledgements
I would like to first thank my adviser, Dr. Karen LaBat. She constantly provided
me with insight and encouragement during the entire dissertation process. From the
brainstorming stage of the dissertation to the final editing stage, she patiently advised me
with enthusiasm. She helped me to grow and become a better and more confident
researcher.
I would like to thank the other committee members – Dr. Elizabeth Bye, Dr.
Marilyn DeLong, and Dr. Gary Meyer. Dr. Elizabeth Bye gave me warm encouragement,
advice, and helped me to better understand apparel fit and size topics, and she served as
the chair of the committee. Dr. Marilyn DeLong gave me positive suggestions and guided
me to view the topic with aesthetics perspective as well. Dr. Gary Meyer offered me
valuable knowledge and perspectives from the Computer Science field.
I want to recognize the support that I received from the department of Design,
Housing, and Apparel. The department supported me through a grant and other resources.
Ms. Charleen Klarquist gave me guidance to follow the required program procedures step
by step. Additionally, I am grateful for the support from the Human Dimensioning©
Laboratory which provided the equipment for this dissertation. In the lab, I met
researchers who helped me to complete my Ph.D. program and this dissertation. In
addition to meeting my adviser and committee members, I have also met my fellow
researchers – Dr. Karen Ryan, Dr. Ellen McKinney, Dr. Chin-Man Chen, and Ms.
MyungHee Sohn. I want to thank them for sharing ideas with me and supporting me.
I would like to further acknowledge the National Science Foundation (NSF) for
providing tools available in the Human Dimensioning© Laboratory. This dissertation was
supported by the National Science Foundation under Grant No. 0321172. I also would
like to acknowledge that this dissertation was supported by Thesis Research Grants from
the Graduate School at the University of Minnesota.
Above all, I want to deeply thank my parents. Their love and encouragement
helped me to continue to pursue to become a learner and a future educator. They have
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always believed that I would finish my Ph.D. program successfully. I would also like to
extend a warm thank you to all my friends who have prayed for me in times of difficulty.
Lastly, I thank God, my Lord Jesus for giving me strength, wisdom, and guidance to
finish my Ph.D. program and this dissertation.
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Abstract
Consumers purchasing apparel online are unable to “try on” products. With the
development of 3D body scanning and 3D virtual garment simulation technologies,
online shopping is becoming more promising. However, little research has been done on
the fidelity and accuracy of 3D virtual dressing software to prove that it can represent a
real person in a garment so that the virtual try-on can be used reliably for apparel fit
assessment.
The purpose of the research was (1) to investigate the fidelity and accuracy of a
3D virtual garment simulation tool in assessing fit on a 3D virtual model by comparing
the resulting fit on the 3D virtual model and on the participant real body through
participant evaluation and (2) to evaluate the effectiveness of the tool for 3D online
virtual clothing shopping for consumers. Ferwerda’s (2003) framework for functional
realism in computer graphics is adapted as a framework for this study.
A 3D virtual garment simulation software package developed by a leading US
company was selected. Thirty-seven participants were recruited. Two questionnaires and
an interview were used to collect quantitative and qualitative data. During the participants’
first visit, each participant was scanned with a VITUS/smart 3D Body Scanner produced
by Human Solutions. Virtual models were made from the participant’s scan. During the
second visit, the participants evaluated fit of their selected pants simulation on their
virtual model. Then, the participants evaluated the test pants fit on their body, and they
compared the test pants fit to the virtual pants fit. The quantitative data from the
questionnaires were analyzed using descriptive statistics, two-way repeated measures
ANOVA, and independent t-test. The qualitative data from the interview were analyzed
using the content analysis technique.
The general participant responses were that the visual information from the virtual
model provided them with an overall idea about the pants fit. They were especially
impressed that the visual information of overall pants silhouette in relation to their body
shape was very accurate. Additionally, the virtual garment simulation accurately
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represented the test pants length and the waistband position. However, the simulation
was not completely accurate. The major difference between the fit on the virtual model
and the fit on the body was inaccurate material representations. The fabric simulation was
laying smoothly on the virtual model, but many wrinkles were visible on the body.
Additionally, the fabric texture was inaccurately represented and the simulated fabric was
described as resembling a knit fabric.
Technological limitations were found in accurately representing garment to body
shape relationships. Because 3D images from a body scanner were solid and
uncompressible images, the shape of the body scan images could not be modified in
accordance to garment tension. Due to this limitation, in some cases, the pants size was
inaccurately represented.
The results led to the conclusion that the overall accuracy of the virtual simulation
tool was moderately good but not to the extent that the participants could perform all the
aspects of the meaningful task of the fit evaluation that were important. This indicates
that the fidelity of the virtual simulation tool was moderate as well. The results of the
study will help software developers in improving the 3D virtual dressing technologies
that are accurate enough for consumers to make a satisfactory and reliable online
purchase decision.

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Table of Contents
Acknowledgements .............................................................................................................. i
Abstract .............................................................................................................................. iii
Table of Contents ................................................................................................................ v
List of Tables .................................................................................................................... vii
List of Figures .................................................................................................................... ix
CHAPTER ONE: INTRODUCTION ................................................................................. 1
CHAPTER TWO: LITERATURE REVIEW ..................................................................... 3
Apparel Fit ...................................................................................................................... 3
Online Shopping ............................................................................................................. 7
Mass Customization ........................................................................................................ 8
3D Technology for Mass Customization ...................................................................... 11
Limitation of Virtual Technology ................................................................................. 12
Virtual Simulation Technology..................................................................................... 13
Visual Perception in Computer Graphics ..................................................................... 17
Summary: Literature Review ........................................................................................ 20
CHAPTER THREE: METHODOLOGY ......................................................................... 21
Research Design............................................................................................................ 21
Research Purpose ...................................................................................................... 21
Research Question .................................................................................................... 22
Limitations .................................................................................................................... 22
Participant Selection ..................................................................................................... 23
Questionnaire and Interview ......................................................................................... 23
Participant Information Form ................................................................................... 24
Participant Fit Evaluation Questionnaire and Interview ........................................... 24
Data Collection Procedure ............................................................................................ 25
Selection of 3D Virtual Garment Simulation Software ............................................ 25
First Step: Preparation of Test Pants Pattern ............................................................ 25
Garment Design and Pattern ................................................................................. 25
Fabric .................................................................................................................... 26
Second Step: Preparation of 3D virtual self-model .................................................. 29
Participant First Visit: Scan and Participant Information Form ........................... 29
3D VM Preparation ............................................................................................... 30
Third Step: Participants Fit Evaluation ..................................................................... 30
Fit Test on the Participant’s Virtual Body ............................................................ 31
Fit Test on the PB ................................................................................................. 32
Data Analysis Procedure ............................................................................................... 34
Quantitative Data Analysis ....................................................................................... 34
Qualitative Data Analysis ......................................................................................... 35
Summary: Methodology ............................................................................................... 36
CHAPTER FOUR: RESULTS ......................................................................................... 37
Analysis of Demographic Information ......................................................................... 37
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Comparison between Fit on the VM and on the PB ..................................................... 39
Test Pants Size Selected by Participants ................................................................... 40
Fit Expectation .......................................................................................................... 41
Two-way Repeated-Measures ANOVA Results ...................................................... 42
Participant’s Comparison between Fit on the VM and on the PB ............................ 45
Independent t-Test by College Major ................................................................... 46
Summary of Participant’s Comparison between Fit on the VM and on the PB ... 48
Overall: Descriptive Statistics............................................................................... 48
Front and Back Waistband: Descriptive Statistics ................................................ 49
Front and Back Waistband: Qualitative Analysis ................................................. 51
Abdomen: Descriptive Statistics ........................................................................... 57
Abdomen: Qualitative Analysis ............................................................................ 58
Hip: Descriptive Statistics..................................................................................... 63
Hip: Qualitative Analysis ...................................................................................... 64
Front and Back Thigh: Descriptive Statistics ....................................................... 69
Front and Back Thigh: Qualitative Analysis ........................................................ 71
Front and Back Crotch: Descriptive Statistics ...................................................... 76
Front and Back Crotch: Qualitative Analysis ....................................................... 78
Left Side & Right Side: Descriptive Statistics ...................................................... 84
Left and Right Side: Qualitative Analysis ............................................................ 85
Inseam: Descriptive Statistics ............................................................................... 89
Inseam: Qualitative Analysis ................................................................................ 90
Hem: Descriptive Statistics ................................................................................... 93
Hem: Qualitative Analysis .................................................................................... 94
Summary: Comparison between Fit on the VM and on the PB .................................... 99
Opinions on Using the VM and Future Willingness to use the VM ........................... 100
Quantitative Analysis .............................................................................................. 101
Qualitative Analysis ................................................................................................ 108
Summary: Opinions on Using the VM and Future Willingness to use the VM ......... 114
CHAPTER FIVE: DISCUSSIONS AND CONCLUSION ............................................ 115
Discussions ................................................................................................................. 115
Material ................................................................................................................... 117
Shape ....................................................................................................................... 119
Size .......................................................................................................................... 122
Length ..................................................................................................................... 123
Location .................................................................................................................. 124
Sensory Limitation .................................................................................................. 125
Body Scanning: Privacy and Modesty Concerns .................................................... 125
Pants Style Issue ..................................................................................................... 126
Conclusion .................................................................................................................. 126
BIBIOGRAPHY ............................................................................................................. 129
APPENDIX A: Participant Information Form ................................................................ 135
APPENDIX B: Participant Evaluation of Pant Fit: On Virtual Model ........................... 137
APPENDIX C: Participant Evaluation of Pant Fit: On the Body ................................... 140
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List of Tables
Table 1 Mass Customization Model for Clothing (Loker, 2007, p. 247) …………..… p. 9
Table 2 Ages of Participants ………………………………………………….……... p. 38
Table 3 College Major of Participants ……………………………………….……… p. 38
Table 4 School Year of Participants ………………………………………………… p. 39
Table 5 Self Assessment of Fit Knowledge .………………………………………… p. 39
Table 6 Test Pants Size Selected by Participants …...………………...………...…… p. 40
Table 7 Participant Expectations for the Fit of Pants on Their Personal Body …...… p. 41
Table 8 Hypotheses for the Two-Way Repeated-Measures ANOVA ……..……...… p. 42
Table 9 Two-way Repeated-Measures ANOVA on Participant Fit Evaluation …..… p. 43
Table 10 Mean Differences between the Two Evaluation Types ………………....… p. 45
Table 11 T-Test for Ratings of Comparison of the Fit on the VM to the Fit on the PB by
Clothing Design Students and Non-Clothing Design Students ...…………… p. 47
Table 12 Comparison of Overall Fit ………………………………………………… p. 49
Table 13 Comparison of Front Waistband Fit …………………………….………… p. 50
Table 14 Comparison of Back Waistband Fit ……………………………..………… p. 50
Table 15 Waistband Fit Evaluation on the VM and PB by Participants …..………… p. 51
Table 16 Comparison of Abdomen Fit …….......…………………………….……… p. 57
Table 17 Abdomen Fit Evaluation on the VM and PB by Participants ………...…… p. 58
Table 18 Comparison of Hip Fit …………………………………………………..… p. 63
Table 19 Hip Fit Evaluation on the VM and PB by Participants ……………………. p. 64
Table 20 Comparison of Front Thigh Fit ……………………………………...…….. p. 70
Table 21 Comparison of Back Thigh Fit ……………………………………...…….. p. 70
Table 22 Thigh Fit Evaluation on the VM and PB by Participants ………………..... p. 71
Table 23 Comparison of Front Crotch Fit ………………………………………….... p. 77
Table 24 Comparison of Back Crotch Fit …………………………………………… p. 77
Table 25 Crotch Fit Evaluation on the VM and PB by Participants ………………… p. 78
Table 26 Comparison of Left and Right Side Fit ……………………………………. p. 84
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Table 27 Side Fit Evaluation on the VM and PB by Participants ………………….... p. 85
Table 28 Comparison of Inseam Fit …………………………………………………. p. 89
Table 29 Inseam Fit Evaluation on the VM and PB by Participants …………..……. p. 90
Table 30 Comparison of Hem Fit ………………………………………………..….. p. 94
Table 31 Hem Fit Evaluation on the VM and PB by Participants ……………….… p. 94
Table 32 T-Test for Satisfaction with VM by Clothing Design Students and Non-Clothing
Design Students ………………………………………………………...….. p. 101
Table 33 Level of Visual Information from VM ………………………………...… p. 103
Table 34 Satisfaction with Using a VM ………………………………………….… p. 104
Table 35 Satisfaction with Using a VM in Purchasing Pants ……………………… p. 104
Table 36 Likelihood of Returning Pants …………………………………………… p. 105
Table 37 Likelihood of Using VM ……………………………………………….… p. 106
Table 38 Likelihood of Using VM for Apparel Online Shopping ……………….… p. 107
Table 39 Willingness to Pay Additional Fee to Use VM ……………………………p. 107
Table 40 Additional Payment Amount …………………………………………..… p. 108

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