Mô phỏng ứng xử cơ học da người bằng phương pháp phần tử hữu hạn

I H C QU C GIA TP HCM TR NG I H C BÁCH KHOA INH SONG NG C TH CH MÔ PH NG NG X C H C DA NG PHÁP PH N T I B NG PH H UH N Chuyên ngành: C K THU T Mã s : 8520103 LU N V N TH C S TP H CHÍ MINH, tháng 06 n m 2022 i NG CƠNG TRÌNH TR Cán b h NG C HỒN THÀNH T I I H C BÁCH KHOA – HQG – HCM ng d n khoa h c: TS Nguy n Thanh Nhã Cán b ch m nh n xét 1: TS Tr ng Quang Tri Cán b ch m nh n xét 2: TS Nguy n Ng c Minh Lu n v n th c s đ c b o v t i Tr ng ngày 30 tháng 06 n m 2022 i h c Bách Khoa, HQG Tp HCM Thành ph n H i đ ng đánh giá lu n v n th c s g m: PGS.TS Tr TS Tr ng Tích Thi n – Ch t ch ng Quang Tri – Cán b ph n bi n TS Nguy n Ng c Minh – Cán b ph n bi n TS Nguy n Duy Kh – U viên TS Ph m B o Toàn ng – Th ký Xác nh n c a Ch t ch H i đ ng đánh giá LV Tr ngành sau lu n v n đ c s a ch a (n u có) CH T CH H I NG TR ng Khoa qu n lý chuyên NG KHOA KHOA H C ii NG D NG TR I H C QU C GIA TP.HCM NG I H C BÁCH KHOA C NG HÒA XÃ H I CH NGH A VI T NAM c l p - T - H nh phúc NHI M V LU N V N TH C S H tên h c viên: inh Song Ng c Th ch MSHV: 1870607 Ngày, tháng, n m sinh: 19/09/1991 N i sinh: Tp HCM Chuyên ngành: C K Thu t Mã s : 8320101 I TÊN TÀI MÔ PH NG NG X C H C DA NG I B NG PH NG PHÁP PH N T H UH N MECHANICAL BEHAVIOR SIMULATION FOR HUMAN SKIN USING FINITE ELEMENT METHOD II NHI M V VÀ N I DUNG: - Tìm hi u mơ hình v t li u siêu đàn h i dùng mô ph ng ng x c h c da ng - Tính tốn – mơ ph ng ng x phi n c a da ng i b ng ph i ng pháp ph n t h u h n III NGÀY GIAO NHI M V : 06/09/2021 IV NGÀY HOÀN THÀNH NHI M V : 09/06/2022 V CÁN B H NG D N: TS Nguy n Thanh Nhã Tp HCM, ngày 09 tháng 06 n m 2022 CÁN B H NG D N TR CH NHI M B NG KHOA KHOA H C iii MÔN ÀO T O NG D NG L IC M Lu n v n không th đ th y, ng ih N c hoàn thành n u khơng có s ch d n t n tình c a ng i ng d n c a tác gi , TS Nguy n Thanh Nhã T t n đáy lòng, em xin chân thành c m n th y không ng ng giúp đ , kiên nh n nhi t tình su t kho ng th i gian th c hi n lu n v n Bên c nh đó, em xin c m n gi ng viên B môn C K Thu t t n tình gi ng d y, ch b o th i gian em kho ng th i gian em theo h c ch Th c s Ngoài ra, em xin c m n nh ng l i góp ý c a PGS.TS Tr ng trình ng Tích Thi n PGS.TS V Cơng Hịa góp ph n hồn thi n lu n v n Cu i cùng, g i đ n gia đình, ng i thân bên c ch đ ng viên, dành nh ng tình c m chân thành, góp ph n t o đ ng l c đ tác gi hoàn thành lu n v n H C VIÊN / TÁC GI LU N V N INH SONG NG C TH CH iv TÓM T T LU N V N ng x c h c c a da ng i hi n v n ch a đ c hi u rõ m t cách c n k đ c tính c a da r t ph c t p c u trúc sinh h c c a Trong l nh v c liên quan đ n c sinh h c v da, vi c hi u rõ đ c tính c h c xác đ nh thông s v t li u c a da u c n thi t, góp ph n phát tri n nh ng d ng c y t (kh u trang, thi t b k p v t th ng, d ng c th thao,…) ho c s n ph m ti p xúc tr c ti p v i da ng i (Ví d : dao c o râu, máy r a m t,…) B i lý trên, c n thi t xây d ng m t mơ hình da ng i chu n đ xác đ nh thông s v t li u hi u rõ h n v ng x c a Trong lu n v n này, mơ hình da kh y tay đ c phát tri n thơng qua phân tích ph n t h u h n phi n (nonlinear FEA), b ng cách s d ng công c ch S li u ph ng pháp th c hi n đ c d a d li u tham kh o thí nghi m th c nghi m c a tác gi Jamaluddin Mahmud, mơ hình da ng mơ hình v t li u siêu đàn h i v t li u Ogden đ mơ hình FEA s đ ng trình ANSYS iđ c xem xét mơ t tính ch t c h c thơng s v t li u, mơ hình c l a ch n cho tính tốn mơ ph ng Các k t qu chuy n v thu đ ct c so sánh v i d li u chuy n v t th c nghi m đ xác đ nh đ c tính c h c c a da ng i Ngoài ra, ph ng pháp s đ c x d ng đ xác đ nh tính phù h p c a h s s m c a mô hình v t li u Ogden T có th k t lu n r ng thông s v t li u có th s d ng đ mơ ph ng cho da ng tính tốn ng x c a da ng i có v t th i Sau cùng, m t s k t qu ng v i mơ hình v t li u Ogden đ nh m minh h a kh n ng ng d ng c a đ tài v c th c hi n ABTRACT The mechanical behavior of human skin is still not well understood, and its properties are complex because of biological structure In biomechanics related fields, understanding the mechanical properties of skin is essential, especially in computation and simulation In this paper, the nonlinear finite element analysis (FEA), with the help of the ANSYS program, is performed to develop a human arm skin model based on the reference data from Vivo experiments given by the previous study of other researchers The analysis consists of two nonlinear types including large deformation and material nonlinearities The Ogden model is applied as a hyper-elastic material model for the problems, the obtained displacement results given by the FEA model are compared with available experimental data to verify the actual mechanical properties of the interested human skin The numerical solution has confirmed Ogden's coefficients and exponent, and these parameters can be used for human arm skin simulation vi L I CAM OAN Lu n v n đ c th c hi n b i tác gi , d Thanh Nhã T t c s li u k t qu đ is h ng d n c a TS Nguy n c đ a lu n v n đ u đ c tác gi xác đ nh trình nghiên c u không chép t b t c tài li u tham kh o khác H c viên/ Tác gi lu n v n Đinh Song Ng c Th ch vii M CL C Danh M c Hình nh x Danh m c b ng bi u xii Danh M c Ch vi t t t Ký hi u toán h c xiii CH NG GI I THI U 1.1 T ng quan 1.2 M c tiêu đ tài 1.3 Ph 1.4 ng pháp nghiên c u it ng, ph m vi nghiên c u 1.5 S n ph m d ki n b c c lu n v n CH NG C S LÝ THUY T 2.1 Mơ hình v t li u cho da ng i 2.1.1 L a ch n mơ hình v t li u siêu đàn h i 2.1.2 Gi i thi u mơ hình v t li u Ogden 2.2 Mơ hình v t li u Ogden đ i v i t m màng m ng 2.2.1 Tính tốn ng su t 2.2.2 Tuy n tính hóa tensor ng su t b c hai Piola – Krichhoff 10 2.2.3 Bi n đ i ph 2.2.4 Ph CH ng trình tr ng thái cân b ng 12 ng trình ph n t h u h n 13 NG PH NG PHÁP NGHIÊN C U 17 3.1 Gi i thi u h th ng “N m b t chuy n đ ng” đ i v i chuy n v c a da ng i s ng 17 3.2 Mơ hình ph n t h u h n cho da ng i 17 3.3 Thông tin d li u th c nghi m c a nh ng nghiên c u tr c 20 3.4 Mơ hình tính tốn 22 viii CH NG PHÂN TÍCH PH N T NG X H U H N CHO DA NG DA CÓ V T TH I VÀ MÔ PH NG NG 23 4.1 Xác th c mơ hình tính tốn s 23 4.2 Xây d ng mô hình ph n t h u h n đ i v i mô ph ng da ng i 24 4.2.1 T i u ki n biên 25 4.2.2 L a ch n thông s v t li u 25 4.3 K t qu mô ph ng ki m ch ng thông s v t li u 26 4.3.1 Tr ng h p nghiên c u 1: Mơ hình da 2D 26 4.3.2 Tr ng h p nghiên c u 2: Mơ hình da 3D 30 4.4 ng d ng mơ hình v t li u thu đ ng c mô ph ng ng x v t th da i 35 4.4.1 Gi i thi u v v t th 4.4.2 Ph ng h ng pháp u tr v t th da ng i 35 ng h da b ng khung kéo 36 4.4.3 K t qu mô ph ng ng x v t th CH ng h ng h u tr b ng khung kéo da 38 NG TH O LU N VÀ K T LU N 42 5.1 Th o lu n 42 5.2 H n ch c a lu n v n 42 5.3 K t lu n 42 5.4 H ng phát tri n 43 DANH M C CÁC CƠNG TRÌNH NGHIÊN C U KHOA H C 44 TÀI LI U THAM KH O 45 LÝ L CH TRÍCH NGANG 47 QUÁ TRÌNH ÀO T O 47 Q TRÌNH CƠNG TÁC 47 ix Danh M c Hình nh Hình 1.1 S đ m t c t ngang c a da ng Hình 2.1 Mơ hình liên t c tr i cho th y l p riêng bi t c sau bi n d ng Hình 3.2 Quy trình mơ ph ng da ng i t thông s th c nghi m [3] 21 Hình 3.3 Mơ hình t m m ng m ng đ c xây d ng b ng ANSYS 22 Hình 4.1 Mơ hình ph n t h u h n cho toán c n xác th c 24 Hình 4.2 K t qu mô ph ng chuy n v đ c so sánh v i k t qu c a Grttmann Taylor 24 Hình 4.3 T i u ki n biên c a mơ hình Ph n t h u h n c a da 25 Hình 4.4 Bi n d ng d c tr c t ng c a da (Thông s v t li u Ogden = 10 Pa, = 110) 26 Hình 4.5 So sánh k t qu mơ ph ng ( ph n t PLANE183, b n c p tham s c a Ogden, 48 ph n t ) v i d li u tham chi u 27 Hình 4.6 So sánh k t qu mô ph ng ( ph n t PLANE183, b n c p tham s c a Ogden, 192 ph n t ) v i d li u tham chi u 28 Hình 4.7 So sánh k t qu mô ph ng ( ph n t PLANE183, b n c p tham s c a Ogden, 768 ph n t ) v i d li u tham chi u 29 Hình 4.8 So sánh k t qu mô ph ng tr L i trung bình, L Hình 4.9 ng h p nghiên c u (L i thô, i m n) v i d li u tham chi u 29 ng x bi n d ng da có n p nh n 31 Hình 4.10 So sánh k t qu mô ph ng ( ph n t SOLID186, b n c p tham s c a Ogden, 48 ph n t ) v i d li u tham chi u 31 Hình 4.11 ng x c a da ng i chia l i m n 32 Hình 4.12 So sánh k t qu mô ph ng ( ph n t SOLID186, b n c p tham s c a Ogden, 192 ph n t ) v i d li u tham chi u 33 x Co-Chair: Assoc Prof Dr Zulkepli bin Majid Deputy Dean of Faculty of Built Environment and Surveying Workshop Committee Members: Sr Dr Mohd Farid Mohd Ariff Sr Ts Gs Dr Muhamad Uznir Ujang Co-Chair: Assoc Prof ChM Dr Zaiton binti Abdul Majid Dean of Faculty of Science Publication Committee Members: Dr Nurriza binti Ab Latif Assoc Prof ChM Dr Shajarahtunnur Jamil Dr Khairunadwa Jemon Dr Zaiton Md Isa Dr Alireza Samavati Muhammad Syafiq bin Hazlan Co-Chair: Assoc Prof Dr Mohd Ismid bin Md Said Pro-Vice Chancellor (International) Local Arrangement Committee Technical & Logistics Committee Members: Prof Dr Nor Haniza binti Sarmin Dr Farhana Diana binti Deris Cik Nurul Izzati binti Mohd Twa Dr Nadzirah binti Hosen Pn Siti Mariyam Mamat Cik Norazreen Ismail En Iqmal Noor Mohamad Noh En Rahim Hashim En Azizul Sulan Pn Fatimawati Masari Pn Fadillah Abdul Hamid Cik Hanis Amirah Roslin xiii TECHNICAL SESSION DAY (23RD FEBRUARY, Wednesday) Civil Engineering and Built Environment Link: https://bit.ly/3BmqMdn Time (GMT +8) 14.00 – 14.15 Paper ID 1570776275 Title of Paper and Presenter CO2 Uptake of Concrete Recycled Fines Carbonated Using Solid-Air and Aqueous Carbonation 14.15 – 14.30 1570777019 14.30 – 14.45 1570777872 Technical Session 14.45 – 15.00 1570777987 Chair: Sr Gs Dr Nurul Hawani Idris 15.00 – 15.15 1570777991 15.15 – 15.30 1570778002 Performance Verification of Visual Odometry with IMUStereo Camera in Indoor UAV 15.30 – 15.45 1570778026 Model-Based Reconstruction of Underground Pipes from Point Clouds for Construction Information Modeling Karen Midori Masunaga Research on Architectural Survey Using Photogrammetry of Mitsumine Shrine Zuishin Gate Yoko Watanabe Ito Disaster Evacuation Route Choice for Urban Informal Settlement: A Conceptual Framework Irsyad Adhi Waskita Hutama Motion Object Recognition Using Range Images Acquired from Point Clouds Gai Ozaki Barriers to the Implementation of Decentralized Green Infrastructure Practice with the Aim of Urban Stormwater Management in Japan Shun Uchiyama Kazuha Saito Kouki Kurita 15.45 – 16.00 16.00 – 16.15 1570778028 16.15 – 16.30 1570778042 16.30 – 16.45 1570778056 16.45 – 17.00 1570779854 17.00 – 17.15 1570779935 Tea break Topology-Based Dense Point Cloud Generation of Texture-Less Regions Yuichiro Yamaguchi Technical Session Chair: Prof Ir Ts Dr Mohd Fadhil Md Din The Relationship Between Land Use Land Cover and Road Blockage Events in Bhutan Dhan Raj Chhetri Experiment on PPP-RTK with Mobile Laser Scanning in Urban River Mapping Kimura Naoto Soft Soil Improvement by Geosynthetic Encased Granular Column: Analytical and Numerical Analyses Phu Nhat Truyen Application of Screw Driving Sounding Test as a Soil Investigation Method in Putrajaya Muhammad Hatta Mohd Satar xxi Energy and Environmental Engineering, Bioscience, Bioengineering and Life Sciences Link: https://bit.ly/3sMGRVx Time (GMT +8) 14.00 – 14.15 Paper ID 1570773132 Title of Paper and Presenter Centrifugal Compressor Performance in Variation of Diffuser Vanes Number 14.15 – 14.30 1570776295 14.30 – 14.45 1570777345 Technical Session 14.45 – 15.00 1570778238 Chair: Dr Rozzeta Dollah 15.00 – 15.15 1570778240 15.15 – 15.30 1570778241 Integrated Production Modeling for Handling Produced Water Issues in Field X 15.30 – 15.45 1570779509 Optimization Bleaching Process Using Hydrogen Peroxide by Microwaves Joko Waluyo Simulation of Bamboo Sawdust Gasification Process and Pilot-Scale Investigation Tu Tan Nhan Le Mechanical Behavior Simulation for Human Skin Using Finite Element Method Thach Song Ngoc Dinh Reconstruction of 3D Flow Field from 2D Flow Data in Multiple Cross-Section Planes Muhammad Aiman Mohd Nor An Improved Approach to Routine and Special Core Analysis Khang Dinh Tran Le Tho Truong Nguyen Maesty Oktavianty Mechanical and Mechatronic Engineering, Transportation and Vehicle Engineering Link: https://bit.ly/3HVua1h Time (GMT +8) 14.00 – 14.15 Paper ID 1570774970 Title of Paper and Presenter Fuzzy PID Controller Design for Nonlinear Quadrotor UAVs 14.15 – 14.30 1570775202 Vehicle Vertical Dynamics Analysis by the 7DOF 3D Model Using Matlab Simmechanics 14.30 – 14.45 1570777183 Estimation of Human Movement Trajectory and Response Control of Interface Robot 14.45 – 15.00 1570777225 15.00 – 15.15 1570777375 15.15 – 15.30 1570777857 15.30 – 15.45 1570777888 Heng Kang Pham Ngoc Dai Technical Session Chair: Assoc Prof Dr Mohd Farid Bin Muhamad Said Eriko Okada Development of Overseas Remote Campus Tour System Using Multiple Robots Yoganata Kristanto Improvement of Sensor Reliability Based on Interconnection Network Yifei Xue Analysis of Image Annotation Method for One-Stage Object Detection Deep Learning Model ChiShen Chao Research on Arousal Maintenance Method Considering Driver's Driving Operation Characteristics Takumi Masamoto xxii 15.45 – 16.00 16.00 – 16.15 1570777906 16.15 – 16.30 1570778057 16.30 – 16.45 1570778122 16.45 – 17.00 1570778130 Tea break Microclimate Regulation System Design in Greenhouse to Promote Precision Agriculture Rezky Mahesa Nanda Technical Session Chair: Assoc Prof Dr Zainul Akmar bin Zakaria Interpolation Method for Sparse Point Cloud at LongRange with RGB-D by LiDAR and Camera Mai Saito Study on Detection of near Miss Accidents in Driving Recorder Data Using Optical Flow Method Hiroto One Pedestrian Detection with Omnidirectional Camera Using Deep Learning Chotaro Yamamoto Electrical and Electronic Engineering, Computer Science and ICT, Global Engineering Science and Technology Link: https://bit.ly/3Jxs9sw Time (GMT +8) 14.00 – 14.15 Paper ID 1570774063 14.15 – 14.30 1570777103 14.30 – 14.45 1570777337 14.45 – 15.00 1570777432 15.00 – 15.15 1570778032 15.15 – 15.30 1570778237 Title of Paper and Presenter Very Short-Term Wind Speed Forecasting Employing a Combination of Long Short-Term Memory and SelfAttention Mechanism Nguyen Duc Tuyen How Users Perceive Communication Quality of VR/AR Applications: Experimental Study Takumi Miyoshi Technical Session Chair: Dr Noraini Ibrahim Graph-Based Signal Processing to Convolutional Neural Networks for Medical Image Segmentation Thuong Le-Tien The Stochastic Unit Commitment Problem Considers Demand Response Based on the Genetic Algorithm Approach Nguyen Duc Tuyen Analysis and Design of Parboiled Rice Production System Devoid Wastewater Boonpipob Teja Evaluating Loss Functions Used for Imbalanced Dataset in Vietnamese Sentiment Analysis Duy Tran Hoan Nguyen 15.30 – 16.00 16.00 – 16.15 1570778239 Technical Session 16.15 – 16.30 1570779531 Chair: Dr Shahliza Abd Halim 16.30 – 16.45 1570780034 Tea break Knowledge Extraction from Source Code: A Testing on C++ Learners' Submissions Nguyen Thanh Nhan Effective of Dye Sensitized Solar Cell with Natural Dye Extraction from Azadirachta Indica Suchat Kongsin An Alternative Assessment Process in the New Norm via Integrated Capstone Data Entry System Rashidah Arsat xxiii DAY (24TH FEBRUARY 2022, Thursday) Business & Technology Management, Social Science and Humanities Link: https://bit.ly/3JvVcN3 Time (GMT +8) 14.00 – 14.15 Paper ID 1570776656 14.15 – 14.30 1570777177 14.30 – 14.45 1570778121 14.45 – 15.00 1570778140 15.00 – 15.15 1570778145 Title of Paper and Presenter Social Learning for Disaster Risk Reduction Through Local Initiatives in the Merapi Volcano Communities Yosi S Mutiarni Technical Session Chair: Dr Nina Diana Nawi Impact of Land Insecurity on the Sustainable Agricultural Development: A Case Study of Agricultural Lands in the Republic of Benin, West Africa Serge Gerard Ekpodessi A Productivity Improvement in Seat Sewing Process for Automotive Industry by Using Simulation Techniques Phatcharee Sangsawang Productivity Improvement of Tractor Part by Improve Plant Layout and Lean Technique Ekagalak Srebankare Productivity Improvement for Lamp Assembly Process in Electronics Industry Chompoonuth Sangthep Material Science and Engineering Link: https://bit.ly/3gQjhC0 Time (GMT +8) 14.00 – 14.15 Paper ID 1570776840 14.15 – 14.30 1570778114 14.30 – 14.45 1570778138 14.45 – 15.00 1570778146 15.00 – 15.15 1570778603 15.15 – 15.30 1570779561 15.30 – 15.45 1570779754 Title of Paper and Presenter Process Improvement Base on Preventive Maintenance: Case Study on Die-Casting Mold Vimonsiri Sirijariyawat Study of Lithium Recovery and Selectivity from NMC Battery Using Organic Acid Leaching Isma Uly Maranggi Precipitation of Calcium Silicate Using Calcium Hydroxide in Geothermal Fluid Afifa Nur Alya Technical Session Chair: Dr Nur Hafizah Binti Abd Khalid Effect of Operating Condition on Lithium Recovery from Synthetic Geothermal Brine Using Direct Contact Membrane Distillation Method Dimas Bagus Galih Utomo Research on Viscosity of Nanofluid Containing Al2O3 Bases on Temperature Pham Son Tung A Study of Using Bacteria Immobilized in Lightweight Aggregate with a Low-Nutrient Source for Self-Healing Concrete by Biomineralization and Promotion of the Hydration Process Nguyen Ngoc Tri Huynh Recovery Selectivity of Lithium from Cathodes NMC Battery with Natrium Hydroxide as a Leaching Agent Rohiman Ahmad Zulkipli xxiv TECHNICAL SESSION MECHANICAL BEHAVIOR SIMULATION FOR HUMAN SKIN USING FINITE ELEMENT METHOD Thach Song Ngoc Dinh (1)(2), *Nha Thanh Nguyen (1)(2), Vay Siu Lo (1)(2), Nghia Trung Tran (1)(2), Thien Tich Truong (1)(2) (1)Faculty of Applied Science, Ho Chi Minh City University of Technology, 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam (2)Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Viet Nam *Corresponding author: nhanguyen@hcmut.edu.vn ABSTRACT The mechanical behavior of human skin is still not well understood, and its properties are complex because of biological structure In biomechanics related fields, understanding the mechanical properties of skin is essential, especially in computation and simulation In this paper, the nonlinear finite element analysis (FEA), with the help of the ANSYS program, is performed to develop a human arm skin model based on the reference data from Vivo experiments given by the previous study of other researchers The analysis consists of two nonlinear types including large deformation and material nonlinearities The Ogden model is applied as a hyper-elastic material model for the problems, the obtained displacement results given by the FEA model are compared with available experimental data to verify the actual mechanical properties of the interested human skin The numerical solution has confirmed Ogden's coefficients and exponent, and these parameters can be used for human arm skin simulation Keywords: Mechanical properties, in vivo human skin, Ogden model, nonlinear analysis, finite element analysis INTRODUCTION Human skin covers the whole body [1] and has a complicated multi-layer structure [2] Therefore, its behavior is very complex, and it has not been known well by research On the other hand, the mechanical behavior of human skin is used for many applications, for example, razors, wearable biomedical devices Thus, understanding the behavior of human skin is essential, and we need an accurate model or mechanical properties Recently, an innovative experimental method using a motion capture system has been developed to measure human skin's deformation in vivo [3] The experimental results were found reliable and valuable The experimental data can be used to analyze deformation, anisotropic, nonlinear behavior of skin, but those data cannot directly measure the mechanical properties of human skin Thus, skin properties are established by simulating skin deformation using the finite element method (or model) and comparing it with experimental data However, unstill now, there is no generally accepted model reported In this study, the experimental data, Ogden's material parameter, and boundary condition are referred to in previous research [3] Based on those data, a simple skin model is developed, and results are compared with experimental data of previous research This paper includes five sections After this introduction part, Section introduces a methodology (data from previous research, FE model, In vivo deformation motion) Section presents the Finite element model of human skin (choosing Ogden's material parameter, boundary condition) In section 4, the results of the deformation of skin and comparison with experimental data of previous research are presented Finally, the conclusion and discussion are provided in section METHODOLOGY 2.1 In vivo skin deformation motion This innovation was developed by Mahmud et al to measure in vivo deformation of the skin utilizing a motion capture system [4, 5] The result is reliable, but it cannot directly determine the mechanical parameter of human skin Because of this reason, a skin model is developed, and it is used to simulate the deformation of skin to replicate the experimental procedure At present, there is no general model that can simulate human skin Therefore, this study attempts to verify that Ogden's material parameters ( = 10 and = 120), which in previous research can be used for mechanical skin parameters 2.2 Finite element modeling of skin The development of a computational model of skin began in '70s where human skin was modeled as an elastic member and a hyper-elastic material However, because of the lack of computer software and modeling tools, a mathematical equation is the foremost 72 approach used to analyze skin deformation Nowadays, with the development of computer technology and FE software, skin deformation simulation can be possible For example, a finite element formulation was proposed for rubberlike membrane shells in [6] Analyzation of human tissue deformation, nonlinear FEM with ANSYS was presented in [7] In the study in [8], ABAQUS was used as a tool to simulate the cupping process Moreover, MSC MARC was chosen to simulate suction tests on the skin [9] In this study, the FE skin model is developed and simulated by ANSYS Four case studies are observed using two elements type, the PLANE183 element, and SLOLID186 element In the case study, which surveys a 2D skin model, PLANE183 with 8-node is used It can be used as a plane element (plane stress, plane strain, and generalized plane strain) or an axisymmetric element (with or without torsion) The element has hyperelasticity, stress stiffening, large deflection, and significant strain capabilities On the other hand, this element can simulate the deformation of fully incompressible hyper-elastic materials For the case study, which surveys a 3D skin model, SOLID186 is used This element is higher-order 3D with 20 nodes solid element It supports plasticity, hyperelasticity, creep, stress stiffening, large deflection, and significant deformation cameras were used for recording and tracking the skin deformation Fig Sample output from the tracking software showing the markers' label and movement The experiment was exported from in vivo test, was used to develop, and simulate the FE skin model After that, Ogden's material parameter is verified DEVELOPMENT OF FE SKIN MODEL 3.1 Ogden's model Ogden's model is a hyper-elastic material model used to describe the nonlinear stress-strain behavior of rubber, polymers, and biological tissue complex material Ogden's model assumes that the strain energy density is a function of three principal stretches (i = 1, 2, 3), in the form of: W = ( λi ) a) b) Fig Element geometry: a) PLANE189 geometry; b) SOLID186 geometry The simulation process and the material parameter of skin based on Ogden's model are referred to Jamaluddin Mahmud et al [3] 2.3 Information and data for the experiments of previous research As mentioned in section 2.2, the data used to develop the skin model is referred to Jamaluddin Mahmud et al [3] In their study, in vivo testing conducted on the skin at the ventral forearm of a healthy volunteer is shown A set of reflective marker stickers was attached to the volunteer arm skin The deformation of the skin was induced by applying tension by pulling a nylon filament attached at the center of the marker set The makers parallel and aligned with the loading direction were labeled P1 to P9, with P5 as a loading point The other end of the filament was attached to a loadcell, and infrared µp α ∑ α (λ N p =1 p p α α + λ2 p + λ3 p − ) (1) (incompressibility condition) and where N, p, p are material parameters Eq (1) gives back Mooney-Rivlin’s strain energy density when N = 2, = 2, = -2 3.2 Numerical validation This part presents the validation of the numerical model that is performed by ANSYS Workbench A square sheet with a circular hole at the center is considered Because of the symmetry, a simplified model of ¼ is used for the simulation The dimensions of the plate are L = 10 mm, R = mm and its thickness is h = mm The model has meshed with 2551 nodes and 812 quadrilateral elements A uniform tensile distribution load q = 90N is applied on the right edge, and the symmetry boundary conditions are set on the left and bottom edges, as shown in Fig The secondorder Ogden’s material parameters are = 50Pa, = and = -14Pa, = -2 The obtained displacement results are compared with the results given by the finite element model [6] to verify the proposed approach The simulation for deformation results is shown in Fig The symbols present the horizontal displacement of points A, B respectively, and 73 denotes the vertical displacement of point C The charts show the agreement between the obtained results with the reference solution Fig Finite element model for the validation problem Gruttman and Taylor [6] Fig The result of the deformation diagram compares with the result of Grattmann and Taylor 3.3 Development of FE model for skin simulation Based on the information in Sections 2.2 and 2.3, the skin simulation has been performed to verify the finite element model for nonlinear skin analysis The computation models are generated with the help of ANSYS Workbench A simplified skin is modeled as a flat square with a dimension of 80 mm x 60 mm The result deformation is compared with experimental data given by Jamaluddin Mahmud et al [3] According to a previous study, Ogden's material coefficient, , and exponent, were considered by varying from 10 to 120 for a constant = 10 Pa For simple simulation and reduced time, the deformation behavior is investigated by varying ( = 40, 50, 110, 120) and retaining ( = 10 Pa) The results were compared to the data of previous research to determine the best match curve Fig Loading and Boundary condition of Finite Element model of skin NUMERICAL RESULTS According to Jamaluddin Mahmud et al [3], the midline markers (P1 to P9) deformation is observed Thus, in this study, only the results of midline markers deformation (P1 to P9) are observed and compared with the data of Jamaluddin Mahmud et al 4.1 Case study 1: 2-D Skin model with coarse mesh The member skin model has meshed into 48 elements (8 x elements) Loading and boundary condition is discussed in section 3.3, PLANE183 element and four pairs of Ogden’s material parameters ( = 10 Pa, = 40; = 10 Pa, = 50; = 10 Pa, = 110; = 10 Pa, = 120) are applied The axial skin deformation is shown in Fig The simulation results show that four of pairs Ogden’s parameter have same be Charts in Fig compare the simulation results with the data of Jamaluddin Mahmud et al The results show that the pair of Ogden's parameters, which is close to the reference data, is ( = 10 Pa, = 110), but the error is insignificant 3.3.1 Load and boundary condition The boundary condition and loading are shown in Fig A load F = 0.7N (red arrow) is applied to the skin model at the center point (marker P5) [3] and is parallel to the middle markers The symbols D1 and D9 present the prescribed displacements of markers P1 and P9 (yellow arrows) [3] 3.3.2 Choosing material parameter In this study, the skin model is considered only nonlinear hyper-elastic, with assumptions stemming from Tong and Fung [13] and Evan [14], and Ogden's model was given good results 74 Fig Compares the simulated results (PLANE183, four pairs of Ogden's parameters, 192 elements) to reference data Fig The total axial skin deformation (Ogden’s material parameter = 10 Pa, = 110) 4.3 Case study 3: 3D Skin model with a coarse mesh This numerical test investigates the third direction (Z-axis) effect and considers Ogden's material parameter, which precisely describes human skin behavior Actually, the 2D skin model cannot match the actual behavior of human skin, and the displacement results show significant errors, so we need to find out the 3D model can exact description the behavior of human skin The 3D skin model is developed as a thin plate with 80 x 60 x mm dimensions The Ogden model is first order (N = 1) The higher-order 3-D 20 nodes solid element (SOLID186) was used with the mesh of 48 elements The load and boundary conditions are referred to the previous investigations Fig shows the behavior of a skin model which have wrinkling Fig 10 shows the comparison of Ogden's material parameter and the reference data The results showed that the material parameters ( = 10 Pa, = 120) give the deformation close to the experimental results Fig The comparison of the simulated results (PLANE183, four pairs of Ogden's parameters, 48 elements) to reference data 4.2 Case study 2: 2-D Skin model with a finer mesh In the previous case study, the number of elements was 48 (8 x elements), and the results showed significant error In this observation, the number of elements is increased to 192 PLANE183 elements (16 x 12 elements) The load, boundary condition, element type, and Ogden's material parameter are the same with those in Section 4.1 The comparison is shown in Fig Both of Ogden’s material parameter ( = 10 Pa, = 40) and ( = 10 Pa, = 110) give acceptable results of skin deformation that are close to the data of Jamaluddin Mahmud et al [3], but ( = 10 Pa, = 40) give better results that fit very well with the experimental solution Fig The behavior of skin deformation, which has wrinkling 75 Fig 10 Compares the simulated results (SOLID 186, four pairs of Ogden's parameters, 48 elements) to reference data 4.4 Case study 4: 3D Skin model with a finer mesh The case study in section 4.2 showed that 3D model can give well deformation results It can describe more exactly skin behavior, but the error is still This example takes the same boundary condition, element type, Ogden's material parameter and 3D model with Section 4.3 However, the number of elements is increased to 192 elements The simulation shows that the pair of Ogden's parameters ( = 10 Pa, = 120) still gives good results Fig 11 shows the skin behavior with finer mesh than previous example Plots in Fig 12 displays the comparison the deformation between simulation and experimental data The 3D models show the reality behavior and very much display the bow wave Fig 11 The fine element's skin behavior with finer mesh Fig 12 Compares the simulated results (SOLID 186, four pairs of Ogden's parameters, 192 elements) to reference data DISCUSSION AND CONCLUSIONS 5.1 Discussion In general, all results from case studies can decrease the hyper-elastic behavior of human skin This paper tries to investigate the effects in the implementation, i.e., Ogden's material parameters, and develop an FE modeling and simulation of human skin The problem of this study is to determine boundary conditions, their difference from experimental data (which applied prescribed displacement for each node) Therefore, 2D model deformation results have significant errors compared with data from previous research On the other hand, the 3D model is more accurate when describing human skin behavior Using the material parameter ( = 10 Pa, = 120), 3D elements (SOLID186) produced results close to the reference data Moreover, this model shows an approximate bow wave shape and wrinkling at the test area However, developing an FE model for human skin takes time, and the boundary condition is hard to verify 5.2 Conclusion After investigating all case studies to determine the mechanical properties of human skin using FE modeling and simulation, the hyper-elastic properties are = 10 Pa, = 120 Although the results are not close to other research data and FE implementation was developed is tedious Still, this paper's study has been found to enhance the knowledge about modeling skin using FEA and ANSYS On the other hand, the development of the FE model can reduce the expenses of experiment testing Ogden's material parameter can use for different skin areas, and in the future, it can help biomechanics or biomedical developments REFERENCES [1] Payne, P A., 1991 "Measurement of properties and function of skin." Clinical Physics & Physiological Measurement, Vol 12(2) pp 105-129 [2] Mahmud, J., Evans, S L., Holt, C A., 2012 "An innovative tool to measure human skin strain distribution in vivo using motion capture and Delaunay Mesh" Journal of Mechanics, Vol 28 (2), pp 309-317 [3] Jamaluddin Mahmud, Cathy Holtb, Sam Evansb, Nor Fazli Adull Manana, Mahmoud Chizaric, "A Parametric Study and Simulations in Quantifying Human Skin Hyperelastic Parameters." International Symposium on Robotics and Intelligent Sensors 2012 (IRIS 2012) [4] Mahmud, J., 2009 "The Development of a Novel Technique in Measuring Human Skin Deformation in vivo to Determine its Mechanical Properties." PhD Thesis, Cardiff University, UK [5] Mahmud, J., Holt, C A., Evans, S L., 2010 "An innovative application of a small scale motion analysis technique to quantify human skin deformation in vivo" Journal of Biomechanics, Vol 43, pp 10021006 [6] Gruttmann F, Taylor RL "Theory and finite element formulation of rubberlike membrane shells using principal stretches" International Journal for Numerical Methods in Engineering 1992, vol 35, pp 1111-1126 76 [7] Tsap, L V., Goldgof, D B., and Sarkar, S., 1997 "Human Skin and Hand Motion Analysis from Range Image Sequences Using Nonlinear FEM" IEEE Nonrigid and Articulated Motion Workshop (in conjunction with IEEE Conference on Computer Vision and Pattern Recognition CVPR'97), San Juan, Puerto Rico [8] Tham, L M., Lee, H P., Lu, C., 2006 "Cupping: from a biomechanical perspective" Journal of Biomechanics Vol 39, pp 2183-2193 [9] Hendriks FM, Brokken D, Van Eemeren J T W M., Oomens C W J., Baaijens F P T., Horsten J B A M., 2003 "A numerical-experimental method to characterize the nonlinear behaviour of human skin" Skin Research and Technology, Vol 9(3), pp 274-283 [10] Basar, Y and Itskov, M., 1998 "Finite element formulation of Ogden material model with application to rubberlike shells" International Journal for Numerical Methods in Engineering Vol 42, pp 1279-1305 [11] R W Ogden "Large Deformation Isotropic Elasticity - On the Correlation of Theory and Experiment for Incompressible Rubberlike Solids" Proc R Soc Lond A 1972 326, 565-584 [12] Horst Parisch “Efficient non-linear finite element shell formulation involving large strains” Institut für Statik und Dynamik der Luft- und Raumfahrtkonstruktionen, University of Stuttgart, D7000 Stuttgart 80, Federal Republic of Germany (Received July 1985) [13] Tong, P., Fung, Y C., 1976 "The stress-strain relationship for the skin" Journal of Biomechanics Vol 9(10), pp 649-657 [14] Evans, S L., 2009 "On the implementation of a wrinkling hyperelastic membrane model for skin and other materials" Computer Methods on Biomechanics and Biomedical Engineering Vol 12(3) pp 319-332 PHOTOS AND INFORMATION Dinh, Song Ngoc Thach received the B.E degrees in 2014 in Engineering Mechanics from Ho Chi Minh City University of Technology, VNU-HCM He is working for Hitachi Zosen Viet Nam as a design engineer, and he is under Engineering Mechanics master program methods Lo, Siu Vay received his B.E (2019) and M.E (2021) degrees in Engineering Mechanics from Ho Chi Minh city University of Technology, VNU-HCM He is currently a teaching assistant at the Department of Engineering Mechanics, Ho Chi Minh city University of Technology His recent interests include fracture mechanics, plate and shell theories and numerical methods Tran, Trung Nghia received his Ph.D degree in Bioengineering and Bioinformatics from Hokkaido University, Hokkaido, Japan in 2014 He currently works at the Laser Technology Laboratory, Faculty of Applied Science, Ho Chi Minh City University of Technology, VNU-HCM His research interest includes the development of biological/medical treatment techniques using low power near-infrared (NIR) laser, fundamental study of laser therapy, transillumination imaging and scattering suppression techniques in biomedical Truong, Tich Thien received his B.E (1986), M.E (1992) and PhD (2001) degrees in Mechanical Engineering from Ho Chi Minh City University of Technology, VNU–HCM He is an Associate Professor of Department of Engineering Mechanics, Ho Chi Minh City University of Technology His current scientific interest includes Structural Analysis, Fracture Mechanics, Biomechanics Nguyen, Thanh Nha received his B.E (2007), M.E (2011) and PhD (2019) degrees in Engineering Mechanics from Ho Chi Minh city University of Technology, VNU-HCM He is a Lecturer, Department of Engineering Mechanics, Ho Chi Minh city University of Technology His current interests include fracture analysis in composite materials and numerical 77 TÀI LI U THAM KH O [1] Y Basar and M Itskov, “Finite element formulation of Ogden material model with application to rubberlike shell,” International Journal for Numerical Methods in Engineering, vol 42, pp 1279-1305, 1998 [2] F Gruttmann, and R.L Taylor, “Theory and finite element formulation of rubberlike membrane shells using principal stretches,” International Journal for Numerical Methods in Engineering, vol 35, pp 1111-1126, 1992 [3] J Mahmud, C Holtb, S Evansb, N.F.A Manana, and M Chizaric, “A Parametric Study and Simulations in Quantifying Human Skin Hyperelastic Parameters,” presented at International Symposium on Robotics and Intelligent Sensors, 2012 (IRIS 2012) [4] J Mahmud, S.L Evans, and C.A Holt, “An innovative tool to measure human skin strain distribution in vivo using motion capture and Delaunay Mesh,” Journal of Mechanics, vol 28, no 2, pp 309-317, 2012 [5] J Mahmud, “The Development of a Novel Technique in Measuring Human Skin Deformation in vivo to determine its Mechanical Properties,” PhD Thesis, Cardiff University, UK, 2009 [6] J Mahmud, C.A Holt, and S.L Evans “An innovative application of a small-scale motion analysis technique to quantify human skin deformation in vivo,” Journal of Biomechanics, vol 43, pp 1002-1006, 2010 [7] L.V Tsap, D.B Goldgof, and S Sarkar, “Human Skin and Hand Motion Analysis from Range Image Sequences Using Nonlinear FEM,” presented at IEEE Nonrigid and Articulated Motion Workshop (in conjunction with IEEE Conference on Computer Vision and Pattern Recognition CVPR'97), San Juan, Puerto Rico, 1997 [8] L.M Tham, H.P Lee, and C Lu, "Cupping: from a biomechanical perspective" Journal of Biomechanics, vol 39, pp 2183-2193, 2006 45 [9] F.M Hendriks et al., "A numerical-experimental method to characterize the nonlinear behaviour of human skin," Skin Research and Technology, vol 9, no 3, pp 274-283, 2003 [10] P Tong, and Y C Fung, "The stress-strain relationship for the skin,"Journal of Biomechanics, vol 9, no 10, pp 649-657, 1976 [11] S.L Evans, "On the implementation of a wrinkling hyperelastic membrane model for skin and other materials," Computer Methods on Biomechanics and Biomedical Engineering, vol 12, no pp 319-332, 2009 [12] R.W Ogden, "Large Deformation Isotropic Elasticity - On the Correlation of Theory and Experiment for Incompressible Rubberlike Solids," Proc R Soc Lond A 326, 565-584, 1972 [13] Horst Parisch, “Efficient non-linear finite element shell formulation involving large strains,” Engineering Computations, vol 3, no 2, pp 121-128, 1986 [14] H Joodaki and M B Panzer “Skin mechanical properties and modeling: A review” Journal Engineering in Medicine, vol 232, no 4, 2018 [15] P.A Payne, "Measurement of properties and function of skin,” Clinical Physics & Physiological Measurement, vol 12, no 2, pp 105-129, 1991 [16] A.J Gallagher, A Ní Anniadh, K Bruyere, M Otténio, and H Xie, M D Gilchrist, “Dynamic Tensile Properties of Human Skin,” IRCOBI Conference 2012, pp 494502, 2012 46 LÝ L CH TRÍCH NGANG H tên: inh Song Ng c Th ch Ngày, tháng, n m sinh: 19/09/1991 a ch liên l c: Chung c H1, đ N i sinh: TP H Chí Minh ng V nh Khánh, ph ng 9, qu n QUÁ TRÌNH ÀO T O - Giai đo n 2009 – 2015: T t nghi p i h c, tr ng i h c Bách Khoa TP HCM, Chuyên ngành C K Thu t - Giai đo n 2018 – 2022: H c Cao h c t i tr ng i h c Bách Khoa Tp HCM, chuyên ngành C K Thu t Q TRÌNH CƠNG TÁC - Giai đo n 2015 – 2016: Làm vi c t i công ty TNHH Hitachi Zosen Vi t Nam - Giai đo n 2016 – 3/2017: OJT (On-job trainning) t i Hitachi Zosen Cooperation, Osaka, Nh t B n - Giai đo n 4/2017 – nay: Tr v Vi t Nam ti p t c công tác t i Hitachi Zosen Vi t Nam 47 ... PH N T NG X H U H N CHO DA NG DA CÓ V T TH I VÀ MÔ PH NG NG 23 4.1 Xác th c mô hình tính tốn s 23 4.2 Xây d ng mơ hình ph n t h u h n đ i v i mô ph ng da ng i 24 4.2.1 T i u... li u thu đ ng c mô ph ng ng x v t th da i 35 4.4.1 Gi i thi u v v t th 4.4.2 Ph ng h ng pháp u tr v t th da ng i 35 ng h da b ng khung kéo 36 4.4.3 K t qu mô ph ng ng x v... I DUNG: - Tìm hi u mơ hình v t li u siêu đàn h i dùng mô ph ng ng x c h c da ng - Tính tốn – mô ph ng ng x phi n c a da ng i b ng ph i ng pháp ph n t h u h n III NGÀY GIAO NHI M V : 06/09/2021