Mitigating concussion and researching more about the motion of the brain is vital to develop safer protection gears for athletes and others around the world. The key to furthering research surrounding concussions is to dive deeper into the effect a hit to the head has on the brain. Most areas of this research look to analyze and track the movement of the head. As this may offer an idea as to what happens to the brain, there is still a completely different motion that the brain experiences during a hit. The goal of this project is to offer a realistic method to analyze the motion of the brain via a head and neck replica model. By creating a model with a human like brain within it, the motion of the brain can be tracked via accelerometers. Our goals with this project are to shed light on the lasting damage concussions can do to the brain and potentially study on further concussion prevention technology. What this project aims to accomplish is to create a head and neck model that can more accurately track the actual motion of the head and brain. Selection of the corresponding materials and validation of the model have been conducted. The purpose of creating this model would be to further the understanding of how the brain reacts to certain impacts within different scenarios.
{"title":"Design of Human Head and Neck Replica to Facilitate Concussion and TBI Research","authors":"Peyman Honarmandi, Elias Awikeh","doi":"10.1115/imece2021-72094","DOIUrl":"https://doi.org/10.1115/imece2021-72094","url":null,"abstract":"\u0000 Mitigating concussion and researching more about the motion of the brain is vital to develop safer protection gears for athletes and others around the world. The key to furthering research surrounding concussions is to dive deeper into the effect a hit to the head has on the brain. Most areas of this research look to analyze and track the movement of the head. As this may offer an idea as to what happens to the brain, there is still a completely different motion that the brain experiences during a hit. The goal of this project is to offer a realistic method to analyze the motion of the brain via a head and neck replica model. By creating a model with a human like brain within it, the motion of the brain can be tracked via accelerometers. Our goals with this project are to shed light on the lasting damage concussions can do to the brain and potentially study on further concussion prevention technology. What this project aims to accomplish is to create a head and neck model that can more accurately track the actual motion of the head and brain. Selection of the corresponding materials and validation of the model have been conducted. The purpose of creating this model would be to further the understanding of how the brain reacts to certain impacts within different scenarios.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134226714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sara M. Smith, Justin Marin, Amari Adams, Keith West, Z. Hao
With consideration of a full set of mechanical properties: elasticity, viscosity, and axial and circumferential initial tensions, and radial and axial motion of the arterial wall, this paper presents a theoretical study of pulse wave propagation in arteries and evaluates pulse wave velocity and transmission at the carotid artery (CA) and the ascending aorta (AA). The arterial wall is treated as an initially-tensioned, isotropic, thin-walled membrane, and the flowing blood in the artery is treated as an incompressible Newtonian fluid. Pulse wave propagation in arteries is formulated as a combination of the governing equations of radial and axial motion of the arterial wall, the governing equations of flowing blood in the artery, and the interface conditions that relate the arterial wall variables to the flowing blood variables. We conduct a free wave propagation analysis of the problem and derive a frequency equation. The solution to the frequency equation indicates two waves: Young wave and Lamb wave, propagating in the arterial tree. With the related values at the CA and the AA, we evaluate the influence of arterial wall properties on their wave velocity and transmission, and find the opposite effects of axial and circumferential initial tensions on transmission of both waves. Physiological implications of such influence are discussed.
{"title":"Pulse Wave Velocity and Transmission at the Carotid Artery and the Ascending Aorta","authors":"Sara M. Smith, Justin Marin, Amari Adams, Keith West, Z. Hao","doi":"10.1115/imece2021-69412","DOIUrl":"https://doi.org/10.1115/imece2021-69412","url":null,"abstract":"\u0000 With consideration of a full set of mechanical properties: elasticity, viscosity, and axial and circumferential initial tensions, and radial and axial motion of the arterial wall, this paper presents a theoretical study of pulse wave propagation in arteries and evaluates pulse wave velocity and transmission at the carotid artery (CA) and the ascending aorta (AA). The arterial wall is treated as an initially-tensioned, isotropic, thin-walled membrane, and the flowing blood in the artery is treated as an incompressible Newtonian fluid. Pulse wave propagation in arteries is formulated as a combination of the governing equations of radial and axial motion of the arterial wall, the governing equations of flowing blood in the artery, and the interface conditions that relate the arterial wall variables to the flowing blood variables. We conduct a free wave propagation analysis of the problem and derive a frequency equation. The solution to the frequency equation indicates two waves: Young wave and Lamb wave, propagating in the arterial tree. With the related values at the CA and the AA, we evaluate the influence of arterial wall properties on their wave velocity and transmission, and find the opposite effects of axial and circumferential initial tensions on transmission of both waves. Physiological implications of such influence are discussed.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134433514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Koch, Brandon Richardson, Daniel Schell, D. Piovesan
An Ankle Foot Orthosis, or AFO, is a device used in human rehabilitation to support lower extremities. The device is similar to a brace that is capable of maintaining the stability of a joint while storing some elastic energy to help lifting the legs at the ankle. The main challenge for this design is to determine the optimal stiffness of the device and how such stiffness comes from the distribution of the stiffness at the joints. Furthermore, the device must be stiff enough for athletic play, but be comfortable for clinical scenarios. We performed a set of experiments on a commercial AFO made of carbon fiber. The angles at the ankle and toes were measured during self-paced walking together with the interaction force between the shin and the AFO. Based on such measurements, we estimated the total rotational stiffness of the device and the distribution of stiffness at each joint. A 3-point bending test following ASTM D7264/D7264M-15 standard was used to evaluate the stiffness of the material produced by a Mark II 3D printer capable of printing long fiber composite. After the optimal printing parameters were selected to obtain the desired stiffness of the material, a finite element analysis was performed to design the AFO geometry to match each single joint stiffness. This customized procedure can provide the design specification of a device so to produce the best athletic performances still maintaining comfort.
踝足矫形器(Ankle Foot Orthosis，简称AFO)是一种在人类康复中用于支持下肢的装置。该装置类似于支架，能够保持关节的稳定性，同时储存一些弹性能量，以帮助在脚踝处抬起腿。这种设计的主要挑战是确定设备的最佳刚度，以及这种刚度如何来自关节刚度的分布。此外，该装置必须足够坚硬，适合运动，但临床场景舒适。我们在碳纤维制成的商用AFO上进行了一系列实验。在自定步行走过程中，测量了踝关节和脚趾的角度以及胫骨和AFO之间的相互作用力。基于这些测量，我们估计了装置的总旋转刚度和每个关节的刚度分布。采用ASTM D7264/D7264M-15标准的三点弯曲测试来评估能够打印长纤维复合材料的Mark II 3D打印机生产的材料的刚度。在选择最佳打印参数以获得所需材料刚度后，进行有限元分析以设计AFO几何形状以匹配每个单个关节刚度。这种定制的程序可以提供设备的设计规格，从而产生最佳的运动表现，同时保持舒适。
{"title":"Design of a Carbon Fiber Ankle Foot Orthotic With Optimal Joint Stiffness","authors":"A. Koch, Brandon Richardson, Daniel Schell, D. Piovesan","doi":"10.1115/imece2021-73248","DOIUrl":"https://doi.org/10.1115/imece2021-73248","url":null,"abstract":"\u0000 An Ankle Foot Orthosis, or AFO, is a device used in human rehabilitation to support lower extremities. The device is similar to a brace that is capable of maintaining the stability of a joint while storing some elastic energy to help lifting the legs at the ankle.\u0000 The main challenge for this design is to determine the optimal stiffness of the device and how such stiffness comes from the distribution of the stiffness at the joints. Furthermore, the device must be stiff enough for athletic play, but be comfortable for clinical scenarios.\u0000 We performed a set of experiments on a commercial AFO made of carbon fiber. The angles at the ankle and toes were measured during self-paced walking together with the interaction force between the shin and the AFO. Based on such measurements, we estimated the total rotational stiffness of the device and the distribution of stiffness at each joint. A 3-point bending test following ASTM D7264/D7264M-15 standard was used to evaluate the stiffness of the material produced by a Mark II 3D printer capable of printing long fiber composite. After the optimal printing parameters were selected to obtain the desired stiffness of the material, a finite element analysis was performed to design the AFO geometry to match each single joint stiffness.\u0000 This customized procedure can provide the design specification of a device so to produce the best athletic performances still maintaining comfort.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114517678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Shetty, Lara A. Thompson, P. Sánchez, C. Campana
This paper addresses the design procedures and simulation results from the mechatronic model of the rehabilitation equipment, which can improve the functionality and precision of the ambulatory gait training system. The distinguishing feature of mechatronic systems is the achievement of system functionality through intensive integration. The paper demonstrates how the mechatronic design modeling has helped improve the design and performance of the new rehabilitation equipment built by the authors and is known as Navigaitor. The Navigaitor is designed to aid the patients who need to improve their balance and walk. The mechatronics aspects allow a better understanding of the dynamic behavior and interactions of the components. Depending on the severity of the patient’s injury (stroke survivor, Parkinson, etc.), the oscillatory motion can range from uniform to non-uniform. The motion needs to be converted from the oscillatory sinusoidal motion of the patient into linear motion that the system can follow the patient with minimum lag and maximum stability. The data acquired during the training stage showing a different rate of recovery and response assists the system designers and thereby provides input to fine-tune the system and upgrade the control requirements.
{"title":"Improving the Performance of Ambulatory Gait Training System for Rehabilitation by Mechatronics and Design Simulation","authors":"D. Shetty, Lara A. Thompson, P. Sánchez, C. Campana","doi":"10.1115/imece2021-71487","DOIUrl":"https://doi.org/10.1115/imece2021-71487","url":null,"abstract":"\u0000 This paper addresses the design procedures and simulation results from the mechatronic model of the rehabilitation equipment, which can improve the functionality and precision of the ambulatory gait training system. The distinguishing feature of mechatronic systems is the achievement of system functionality through intensive integration. The paper demonstrates how the mechatronic design modeling has helped improve the design and performance of the new rehabilitation equipment built by the authors and is known as Navigaitor. The Navigaitor is designed to aid the patients who need to improve their balance and walk. The mechatronics aspects allow a better understanding of the dynamic behavior and interactions of the components. Depending on the severity of the patient’s injury (stroke survivor, Parkinson, etc.), the oscillatory motion can range from uniform to non-uniform. The motion needs to be converted from the oscillatory sinusoidal motion of the patient into linear motion that the system can follow the patient with minimum lag and maximum stability. The data acquired during the training stage showing a different rate of recovery and response assists the system designers and thereby provides input to fine-tune the system and upgrade the control requirements.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114375478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Perla C. Sammour, I. Hage, C. Ghnatios, N. Metni, Ré-Mi S. Hage, R. Hamade
The study involves applying the inverse dynamics to calculate the 3-dimensional (3D) reaction forces and moments at the lower limbs namely: hip, knee, and ankle joints. The study is specific to performing the Lebanese folkloric dance known as the “Dabke jump”. The aim is to compare the impact forces generated at the three joints. Also envisioned is to contrast the forces generated for a male (63 Kg) and a female (50.4 kg) dancer (barefoot and while she wears 8.5 cm high heels). The experimental part of the study consists of measuring position data of the right lower limb of the participant when performing the jump. All at once, the reaction forces generated at the impact are synchronously measured. The position data are obtained using the OptiTrack™ motion capture system. The ground reaction forces are measured using the AMTI force plate. Using kinematics analysis in conjunction with inverse dynamics, the filtered and fitted experimental data are then imported into MATLAB® to obtain a table containing all the internal forces and moments at each joint (ankle, knee, and hip joints) as function of time. Next, the results are plotted and compared. Force and moment data are analyzed using R Project for statistical computing software. The boxplot technique is used to identify the presence of outliers. Using both MannWhitney and Krustkal Wallis tests, all joint reaction forces and moments in three dimensions are analyzed, at different time intervals to instantaneously identify the prominent effect on each joint. It is found that the largest impact force is generated at the ankle joint for both subjects. For the male participant, the impact maximum vertical force measured at the ankle is about 2.2 of body weight (BW). For the female participant, a maximum vertical force of 1.84 BW is recorded both barefoot and with heals. The forces and moments obtained for this male individual are larger than those obtained for this female individual. Moreover, for the female participant the vertical forces obtained for all joints when wearing an 8.5 cm high heel are found to be lower than those obtained when she is barefoot. This is most notably recorded at the hip joint where a maximum decrease of 21.2% is observed. This finding suggests that when a dancer performs the “Dabke jump”, wearing an appropriate heel of suitable height will decrease the vertical impact forces on the lower limb joints and decrease the risk of injuries.
{"title":"Lower Limb Joint Reaction Forces and Moments Calculations for a “Dabke Jump”: Application of 3D Inverse Dynamics Technique","authors":"Perla C. Sammour, I. Hage, C. Ghnatios, N. Metni, Ré-Mi S. Hage, R. Hamade","doi":"10.1115/imece2021-68282","DOIUrl":"https://doi.org/10.1115/imece2021-68282","url":null,"abstract":"\u0000 The study involves applying the inverse dynamics to calculate the 3-dimensional (3D) reaction forces and moments at the lower limbs namely: hip, knee, and ankle joints. The study is specific to performing the Lebanese folkloric dance known as the “Dabke jump”. The aim is to compare the impact forces generated at the three joints. Also envisioned is to contrast the forces generated for a male (63 Kg) and a female (50.4 kg) dancer (barefoot and while she wears 8.5 cm high heels).\u0000 The experimental part of the study consists of measuring position data of the right lower limb of the participant when performing the jump. All at once, the reaction forces generated at the impact are synchronously measured. The position data are obtained using the OptiTrack™ motion capture system. The ground reaction forces are measured using the AMTI force plate.\u0000 Using kinematics analysis in conjunction with inverse dynamics, the filtered and fitted experimental data are then imported into MATLAB® to obtain a table containing all the internal forces and moments at each joint (ankle, knee, and hip joints) as function of time. Next, the results are plotted and compared. Force and moment data are analyzed using R Project for statistical computing software. The boxplot technique is used to identify the presence of outliers. Using both MannWhitney and Krustkal Wallis tests, all joint reaction forces and moments in three dimensions are analyzed, at different time intervals to instantaneously identify the prominent effect on each joint.\u0000 It is found that the largest impact force is generated at the ankle joint for both subjects. For the male participant, the impact maximum vertical force measured at the ankle is about 2.2 of body weight (BW). For the female participant, a maximum vertical force of 1.84 BW is recorded both barefoot and with heals. The forces and moments obtained for this male individual are larger than those obtained for this female individual. Moreover, for the female participant the vertical forces obtained for all joints when wearing an 8.5 cm high heel are found to be lower than those obtained when she is barefoot. This is most notably recorded at the hip joint where a maximum decrease of 21.2% is observed. This finding suggests that when a dancer performs the “Dabke jump”, wearing an appropriate heel of suitable height will decrease the vertical impact forces on the lower limb joints and decrease the risk of injuries.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126379022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sarah Vasquez, Thomas G Lipkin, D. Landry, Jenna Currie, P. Radhakrishnan, D. Albrecht, K. Pahlavan
Oral cancer can result in the loss of the tongue through surgical removal known as glossectomy. Patients who have undergone this procedure face challenges during speech, mastication, and deglutition. Currently, tongue prosthetics lack functionality and are mainly cosmetic. Many of these prosthetics are made of wax and connected to a retainer, which attaches to the back molars of the patient. The goal of this project was to develop a self-contained mechatronic tongue prosthesis that can fit within the oral cavity and aid in deglutition. Investigations into various techniques and sensors supporting miniaturization were carried out and magnetic actuation was found to be the most promising technique. The development process involved redesigning the silicone cast to house sensors, selecting sensors and components for magnetic actuation, magnetic field quantification and miniaturizing various other electrical components. The tongue prosthesis was tested, and the displacement was comparable to a normal human tongue. Details from literature review, design iterations, simulations, validation processes, manufacturing challenges and conclusions will be discussed in depth in this paper.
{"title":"Investigating the Use of Magnetic Actuation for a Self-Contained Functional Tongue Prosthetic","authors":"Sarah Vasquez, Thomas G Lipkin, D. Landry, Jenna Currie, P. Radhakrishnan, D. Albrecht, K. Pahlavan","doi":"10.1115/imece2021-69641","DOIUrl":"https://doi.org/10.1115/imece2021-69641","url":null,"abstract":"\u0000 Oral cancer can result in the loss of the tongue through surgical removal known as glossectomy. Patients who have undergone this procedure face challenges during speech, mastication, and deglutition. Currently, tongue prosthetics lack functionality and are mainly cosmetic. Many of these prosthetics are made of wax and connected to a retainer, which attaches to the back molars of the patient. The goal of this project was to develop a self-contained mechatronic tongue prosthesis that can fit within the oral cavity and aid in deglutition. Investigations into various techniques and sensors supporting miniaturization were carried out and magnetic actuation was found to be the most promising technique. The development process involved redesigning the silicone cast to house sensors, selecting sensors and components for magnetic actuation, magnetic field quantification and miniaturizing various other electrical components. The tongue prosthesis was tested, and the displacement was comparable to a normal human tongue. Details from literature review, design iterations, simulations, validation processes, manufacturing challenges and conclusions will be discussed in depth in this paper.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129217281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mild traumatic brain injury (mTBI) and concussion could occur in vehicular accidents, contact sports, or other physical traumas when the head is subjected to high linear or angular acceleration. Understanding the physiology and dynamics of such events has attracted many researchers’ attention. Due to the hidden risks in such events, it is very important to understand the cause and effect of the relative motion between the brain and skull and the implications of normal and shear stresses in the meningeal region. Since the early 70’s to date wide variations of experimental, analytical, and numerical models has been developed to analyze multilayer spherical head impact model to quantify the dynamic response of the human head due to blunt impact and explain the process and likely cause of mild traumatic brain injuries. There are many high-fidelity finite element models and research studies of the various head models, but very limited analytical models to date for parametric studies. Analytical models of head impact play a vital role in predicting relative displacement between skull and brain, transmitted forces, post-impact velocity, and acceleration of the head system. However, to define a reliable mathematical model which can illustrate the mechanisms of motion and deformation of the brain within the skull requires knowledge of dynamics of a multibody system, material properties, boundary conditions at the brain–skull interface, and experimental data or FEM simulation for validation. In this paper, a mathematical model of the brain and meningeal layers, as two separate viscoelastic materials that are modeled using a Kelvin–Voigt model, have been investigated and the motion of the brain relative to the skull during blunt head impacts have been analyzed. Specifically, the model consists of three concentric spherical mediums including a spherical shell (skull), a thin spherical layer (meningeal layer), and a spherical mass (brain). The interface between these spherical mediums consists of springs and dashpots representing stiffness and viscoelasticity of the skull, meningeal layer, and the brain. This model of the head is initially at rest and subjected to an impulse load. The equations of motion for this multi-body system were obtained, solved, and validated by performing a lumped mechanical model and the multibody dynamics finite element analysis simulation. Multiple parametric studies were performed to determine the maximum amplitude of impact force for which there is a contact between the skull and the brain.
{"title":"Analytical Impact Analysis of the Brain Motion in Low-Velocity Head Impacts Using Concentric Viscoelastic Bodies","authors":"P. Thapa, Shahab Mansoor Baghaei, A. Sadegh","doi":"10.1115/imece2021-73590","DOIUrl":"https://doi.org/10.1115/imece2021-73590","url":null,"abstract":"\u0000 Mild traumatic brain injury (mTBI) and concussion could occur in vehicular accidents, contact sports, or other physical traumas when the head is subjected to high linear or angular acceleration. Understanding the physiology and dynamics of such events has attracted many researchers’ attention. Due to the hidden risks in such events, it is very important to understand the cause and effect of the relative motion between the brain and skull and the implications of normal and shear stresses in the meningeal region.\u0000 Since the early 70’s to date wide variations of experimental, analytical, and numerical models has been developed to analyze multilayer spherical head impact model to quantify the dynamic response of the human head due to blunt impact and explain the process and likely cause of mild traumatic brain injuries. There are many high-fidelity finite element models and research studies of the various head models, but very limited analytical models to date for parametric studies. Analytical models of head impact play a vital role in predicting relative displacement between skull and brain, transmitted forces, post-impact velocity, and acceleration of the head system. However, to define a reliable mathematical model which can illustrate the mechanisms of motion and deformation of the brain within the skull requires knowledge of dynamics of a multibody system, material properties, boundary conditions at the brain–skull interface, and experimental data or FEM simulation for validation.\u0000 In this paper, a mathematical model of the brain and meningeal layers, as two separate viscoelastic materials that are modeled using a Kelvin–Voigt model, have been investigated and the motion of the brain relative to the skull during blunt head impacts have been analyzed. Specifically, the model consists of three concentric spherical mediums including a spherical shell (skull), a thin spherical layer (meningeal layer), and a spherical mass (brain). The interface between these spherical mediums consists of springs and dashpots representing stiffness and viscoelasticity of the skull, meningeal layer, and the brain. This model of the head is initially at rest and subjected to an impulse load. The equations of motion for this multi-body system were obtained, solved, and validated by performing a lumped mechanical model and the multibody dynamics finite element analysis simulation. Multiple parametric studies were performed to determine the maximum amplitude of impact force for which there is a contact between the skull and the brain.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126649715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Is it possible to distinguish cells with minimally-invasive method according to the characteristics of cells when moving through the flow path in vitro? A microflow channel with 45 degrees diagonal microgrooves against the mainstream direction has been manufactured by photolithography technique. The flow path between the two transparent PDMS (polydimethylsiloxane) disks (0.05 mm high, 1 mm wide, and 25 mm long) has a rectangular microgroove (4.5 μm deep, 0.2 mm long) at the bottom with variations in groove widths (0.03 mm, 0.04 mm, and 0.05 mm). The deformation and direction change of floating mouse-myoblasts (C2C12) during passage over the microgroove were measured. The experimental result shows that the change in angle tends to be smaller for cells with larger shape changes in the groove. This method may be applicable to classification by cell deformability.
{"title":"Behavior of Cell Flowing Over Oblique Micro Rectangular Groove","authors":"S. Hashimoto, Hiroki Yonezawa, Shogo Uehara","doi":"10.1115/imece2021-69696","DOIUrl":"https://doi.org/10.1115/imece2021-69696","url":null,"abstract":"\u0000 Is it possible to distinguish cells with minimally-invasive method according to the characteristics of cells when moving through the flow path in vitro? A microflow channel with 45 degrees diagonal microgrooves against the mainstream direction has been manufactured by photolithography technique. The flow path between the two transparent PDMS (polydimethylsiloxane) disks (0.05 mm high, 1 mm wide, and 25 mm long) has a rectangular microgroove (4.5 μm deep, 0.2 mm long) at the bottom with variations in groove widths (0.03 mm, 0.04 mm, and 0.05 mm). The deformation and direction change of floating mouse-myoblasts (C2C12) during passage over the microgroove were measured. The experimental result shows that the change in angle tends to be smaller for cells with larger shape changes in the groove. This method may be applicable to classification by cell deformability.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117023011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Three-dimensional printing with carbon fiber has been used to create lower limb prosthetics. However, the fatigue resistance of carbon fiber is understudied. The goal of this work was to quantify the fatigue properties of three-dimensionally printed carbon fiber. Moore bending fatigue specimens were created using a commercially available printer (Markforged, Watertown, MA). Specimens were printed using (1) a chopped carbon fiber matrix or (2) chopped carbon fiber matrix with embedded continuous carbon fiber. Cycles to failure was measured for three bending stress levels: 11.8, 8.8, and 7.4 kpsi. Ultimately, adding continuous carbon fiber to the chopped matrix increased the short cycle fatigue life (i.e. 103) from 17 to 274 MPa and had no effect on the endurance limit. During a single stance phase of the gait cycle, the heel and toe portions of a prosthetic foot experience up to 262 MPa of von Mises stress. This means the carbon fiber produced from three-dimensional printing would last two gait cycles. Hence, lower limb prosthetics cannot yet be made completely from three-dimensionally printed carbon fiber.
{"title":"Fatigue Properties of 3D Printed Carbon Fiber","authors":"A. Schmitz","doi":"10.1115/imece2021-67626","DOIUrl":"https://doi.org/10.1115/imece2021-67626","url":null,"abstract":"\u0000 Three-dimensional printing with carbon fiber has been used to create lower limb prosthetics. However, the fatigue resistance of carbon fiber is understudied. The goal of this work was to quantify the fatigue properties of three-dimensionally printed carbon fiber. Moore bending fatigue specimens were created using a commercially available printer (Markforged, Watertown, MA). Specimens were printed using (1) a chopped carbon fiber matrix or (2) chopped carbon fiber matrix with embedded continuous carbon fiber. Cycles to failure was measured for three bending stress levels: 11.8, 8.8, and 7.4 kpsi. Ultimately, adding continuous carbon fiber to the chopped matrix increased the short cycle fatigue life (i.e. 103) from 17 to 274 MPa and had no effect on the endurance limit. During a single stance phase of the gait cycle, the heel and toe portions of a prosthetic foot experience up to 262 MPa of von Mises stress. This means the carbon fiber produced from three-dimensional printing would last two gait cycles. Hence, lower limb prosthetics cannot yet be made completely from three-dimensionally printed carbon fiber.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128617933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A solid model of a six-month-old child has been developed using average human anatomical characteristics combined with crash test dummy dimensions. The model consisted of a body and limbs, and a neck and head combination with the head being hollow and housing a hemispherical brain. This model was then exposed to a linear sinusoidal input displacement to the chest, and the angular displacement of the skull and brain were observed. The resulting data showed that the oscillatory behavior was a function of frequency, and maximal oscillations existed at a frequency close to the expected natural frequency of the head/neck system, and at a frequency one order of magnitude greater than this frequency. In addition, when a square wave was applied, rather than a sine wave, the resulting oscillation proved to be more violent; and finally, a real input was applied to the model, from previous tests, to discover if a different oscillatory behavior resulted.
{"title":"Effect of Shaking at or Near Resonance of a Simple Head Model on Skull/Brain Connectors","authors":"J. Daboin, P. Saboori","doi":"10.1115/imece2021-69054","DOIUrl":"https://doi.org/10.1115/imece2021-69054","url":null,"abstract":"\u0000 A solid model of a six-month-old child has been developed using average human anatomical characteristics combined with crash test dummy dimensions. The model consisted of a body and limbs, and a neck and head combination with the head being hollow and housing a hemispherical brain. This model was then exposed to a linear sinusoidal input displacement to the chest, and the angular displacement of the skull and brain were observed. The resulting data showed that the oscillatory behavior was a function of frequency, and maximal oscillations existed at a frequency close to the expected natural frequency of the head/neck system, and at a frequency one order of magnitude greater than this frequency. In addition, when a square wave was applied, rather than a sine wave, the resulting oscillation proved to be more violent; and finally, a real input was applied to the model, from previous tests, to discover if a different oscillatory behavior resulted.","PeriodicalId":314012,"journal":{"name":"Volume 5: Biomedical and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114841574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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