Download or read book Skeletal Muscle Contraction Simulation written by Jonathan M. Ford and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Computer generated three-dimensional (3-D) models are being used at increasing rates in the fields of entertainment, education, research, and engineering. One of the aspects of interest includes the behavior and function of the musculoskeletal system. One such tool used by engineers is the finite element method (FEM) to simulate the physics behind muscle mechanics. There are several ways to represent 3-D muscle geometry, namely a bulk, a central line of action and a spline model. The purpose of this study is to exmine how these three representations affect the overall outcome of muscle movement. This is examined in a series of phases with Phase I using primitive geometry as a simplistic representation of muscle. Phases II and III add anatomical representations of the shoulder joint with increasing complexity. Two methods of contraction focused on an applied maximal force (Fmax) and prescribed displacement. Further analyses tested the variability of material properties as well as simulated injury scenarios. The results were compared based on displacement, von Mises stress and solve time. As expected, more complex models took longer to solve. It was also supported that applied force is a preferred method of contraction as it allows for antagonistic and synergistic interaction between muscles. The most important result found in these studies was the consistency in the levels of displacement and stress distribution across the three different 3-D representations of muscle. This stability allows for the interchangeability between the three different representations of muscles and will permit researchers to choose to use either a bulk, central line of action or a spline model. The determination of which 3-D representation to use lies in what physical phenomenon (motion, injury etc.) is being simulated.
Download or read book Anatomy and Physiology written by J. Gordon Betts and published by . This book was released on 2013-04-25 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Coupled Electro Chemical Mechanical Multi Scale Computational Framework for Simulation of Skeletal Muscles written by Yantao Zhang and published by . This book was released on 2015 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work focuses on electro-chemical-mechanical multi-scale simulation of the excitation-contraction of skeletal muscle, including electro-chemical excitation process in the neural system which activates the contraction of muscle fibers, the combined effects of active fiber contraction and passive extracellular matrix (ECM) mechanical deformation, and their resulting force generation in the muscle components. In the neural systems, the Fitzhugh-Nagumo (FHN) equation is solved to simulate the propagation of neural signals (action potential) in neural trees and muscle fibers using multi-dimensional FHN discretizations. The calculated neural signal is consequently used as the input for the calcium dynamics model, which describes the chemical processes in the muscle fibers. Based on the calculated calcium concentration, the activation distribution in the muscle tissue is then obtained, which determines the active force muscle fiber can generate voluntarily. To study the mechanics associated with the composition of muscle fibers and ECM, the microstructure of skeletal muscle is reconstructed from images, from which the homogenized material property in the continuum level is calculated. By varying the microstructure model, their morphological effect on the muscle performance is studied and compared with experimental observation. Computationally, the physiological models in excitation dynamics are solved by finite difference methods, and their accuracy, efficiency and stability conditions are studied respectively. For the cellular and component scale models, the 3-dimensional reproducing kernel particle method (RKPM) together with stabilized conforming nodal integration are employed. The simulation models are constructed based on medical images, where the pixel points are directly used as meshfree nodes. This computational model has been used to investigate the source of reduced force generation associated with ageing or diseases within muscles due to the malfunctioning in the subscale units. Through the proposed computational models, this research demonstrates how the stiffened connective tissue reduces force generation and how the frequency of neural stimulation affects force generation in the skeletal muscle.
Download or read book Modeling and Simulation of Skeletal Muscle for Computer Graphics written by Dongwoon Lee and published by Foundations and Trends(r) in C. This book was released on 2012 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surveys various approaches to model and simulate muscles both morphologically and functionally.
Download or read book Muscular Contraction and the Reflex Control of Movement written by John Farquhar Fulton and published by . This book was released on 1926 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book includes a valuable and extensive bibliography with historical introduction on pages 3-44. It is a detailed study of the physiology of skeletal muscle.
Download or read book Biomechanical Models for Soft Tissue Simulation written by Walter Maurel and published by Springer Science & Business Media. This book was released on 2013-11-22 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: An overview of biomechanical modeling of human soft tissue using nonlinear theoretical mechanics and incremental finite element methods, useful for computer simulation of the human musculoskeletal system.
Download or read book Myocybernetic Control Models of Skeletal Muscle written by Herbert Hatze and published by . This book was released on 1981 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sliding Filament Mechanism in Muscle Contraction written by Haruo Sugi and published by Springer Science & Business Media. This book was released on 2007-04-27 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sliding Filament Mechanism in Muscle Contraction: Fifty Years of Research covers the history of the sliding filament mechanism in muscle contraction from its discovery in 1954 by H.E. Huxley through and including modern day research. Chapters include topics in dynamic X-ray diffraction, electron microscopy, muscle mechanisms, in-vitro motility assay, cardiac versus smooth muscle, motile systems, and much more.
Download or read book A Model of Skeletal Muscular Contraction written by Peter Martin Klauss and published by . This book was released on 1973 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model of skeletal muscular contraction is developed from a diverse group of previously published experimental results. The model attempts to describe the events which take place within a single sarcomere during contraction. Included in the model are a number of separate process models which are new. These include a model for calcium release and reabsorption by the longitudinal vesicles, a model for binding of calcium to troponin, a model for determining the active state from the amount of calcium bound to troponin, a model relating the active state to cross-bridge formation, a model for breakdown of cross-bridges, and a model relating the existing cross-bridges at any time to the active force they generate. The cross-bridges are referred to as the contractile component. The model is completed by a damping element and an elastic element in parallel with the contractile component and another elastic element in series. (Modified author abstract).
Download or read book The Kinetics of Muscle Contraction written by David Clifford Stephen White and published by Pergamon. This book was released on 1975 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Mechanics of Skeletal Muscle Contractions written by Hadi Rahemi and published by . This book was released on 2015 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines relations between skeletal muscle structure, function and mechanical output. Specifically, this thesis considers the effect of regionalization of muscle activity, changes in connective tissue properties and the inclusion of intramuscular fat on the mechanical output from the muscle. These phenomena are typically hard to measure experimentally, and so in order to study these effects a modelling framework was developed to allow manipulations of the structural and functional parameters of the in silica muscles and observe the predicted outcome of the simulations. The tissues within the muscle-tendon unit were modelled as transversely isotropic and nearly incompressible biomaterials. The material properties of the tissues were based on those of previously measured for the human gastrocnemius muscle. The model was tested mathematically and physiologically. Muscle fibre curvatures, along and cross fibre strains and muscle belly force-length predictions were validated against published experimental values. The validated model of human gastrocnemius was used to predict muscle forces for different muscle properties, architectures and contraction conditions. A change in the activity levels between different regions of the muscle resulted in substantial differences in the magnitude and direction of the force vector from the muscle. The stiffness of the aponeuroses highly influenced the magnitude of the force transferred to the tendon at the muscle-tendon junction. The higher the stiffness, the greater the force. This indicates the importance of understanding the differences in the structure and material properties between aponeurosis and tendon with regard to their functions. The increase in adipose tissue (fat) in the skeletal muscles (characteristic of elderly and obese muscle) was simulated by describing the fat distribution in six different ways. The results showed that fatty muscles generate lower force and stress, and the distribution of the fat also impacts the muscle force.
Download or read book Multiscale Multiphysic Modeling of the Skeletal Muscle During Isometric Contraction written by Vincent Carriou and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The neuromuscular and musculoskeletal systems are complex System of Systems (SoS) that perfectly interact to provide motion. From this interaction, muscular force is generated from the muscle activation commanded by the Central Nervous System (CNS) that pilots joint motion. In parallel an electrical activity of the muscle is generated driven by the same command of the CNS. This electrical activity can be measured at the skin surface using electrodes, namely the surface electromyogram (sEMG). The knowledge of how these muscle out comes are generated is highly important in biomechanical and clinical applications. Evaluating and quantifying the interactions arising during the muscle activation are hard and complex to investigate in experimental conditions. Therefore, it is necessary to develop a way to describe and estimate it. In the bioengineering literature, several models of the sEMG and the force generation are provided. They are principally used to describe subparts of themuscular outcomes. These models suffer from several important limitations such lacks of physiological realism, personalization, and representability when a complete muscle is considered. In this work, we propose to construct bioreliable, personalized and fast models describing electrical and mechanical activities of the muscle during contraction. For this purpose, we first propose a model describing the electrical activity at the skin surface of the muscle where this electrical activity is determined from a voluntary command of the Peripheral Nervous System (PNS), activating the muscle fibers that generate a depolarization of their membrane that is filtered by the limbvolume. Once this electrical activity is computed, the recording system, i.e. the High Density sEMG (HD-sEMG) grid is define over the skin where the sEMG signal is determined as a numerical integration of the electrical activity under the electrode area. In this model, the limb is considered as a multilayered cylinder where muscle, adipose and skin tissues are described. Therefore, we propose a mechanical model described at the Motor Unit (MU) scale. The mechanical outcomes (muscle force, stiffness and deformation) are determined from the same voluntary command of the PNS, and is based on the Huxley sliding filaments model upscale at the MU scale using the distribution-moment theory proposed by Zahalak. This model is validated with force profile recorded from a subject implanted with an electrical stimulation device. Finally, we proposed three applications of the proposed models to illustrate their reliability and usefulness. A global sensitivity analysis of the statistics computed over the sEMG signals according to variation of the HD-sEMG electrode grid is performed. Then, we proposed in collaboration a new HDsEMG/force relationship, using personalized simulated data of the Biceps Brachii from the electrical model and a Twitch based model to estimate a specific force profile corresponding to a specific sEMG sensor network and muscle configuration. To conclude, a deformableelectro-mechanicalmodelcouplingthetwoproposedmodelsisproposed. This deformable model updates the limb cylinder anatomy considering isovolumic assumption and respecting incompressible property of the muscle.
Download or read book Mechanical Simulation of Human Skeletal Muscles written by Abid Latif Khan and published by . This book was released on 1977 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Direct Parameter Fitting of Action Potentials in Skeletal Muscle Cells Which Include Longitudinal Segments written by Tyme Suda and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excitation of skeletal muscle cells triggers a large voltage spike known as an action potential (AP), leading to muscle contraction. Modeling of an AP is typically done using the method developed by scientists Hodgkin and Huxley (HH). In the HH method, voltage and time gated Na+ and K+ ionic currents are simulated, along with a positive "Leak" ionic current and capacitive current. Due to the complexity and the computational time required for simulation, direct fitting of HH parameters to experimental APs has rarely been attempted. A previous thesis at Wright State performed direct fitting for the case of a single compartment muscle cell. This study will introduce propagation to the existing model by adding small longitudinal segments simulating the currents flowing and triggering APs in later portions of the cell. If no adjustments to the single compartment HH parameters are made, adding increasing longitudinal segments leads to a very poor simulation of the AP shape. The simulated AP is too wide, and the peak voltage is too low. However, very few clear links between the number of segments and changes in specific HH parameter values were identified. Each parameter was found to vary by at least a factor of 2 between similar data sets. It is clear that multiple parameter sets are allowable, obscuring direct links between segments and parameter values. In order to further understand the robustness of the found parameter sets and to identify what regions of parameter space is allowable in order to achieve a well fit AP a confidence interval test was completed. Scanning through each parameter and fitting the rest revealed that each of [alpha]h_bar, [beta]h_bar, k[beta]h, V_n_bar, k[alpha]n, [alpha]n _bar, [beta]n_bar, and Na permeability hold a well-defined interval in which near perfect fits can be found. While for k[alpha]h, k[beta]n, and k[beta]m no upper-bound was identified, and for K permeability, V_h_bar, k[alpha]m, [beta]m_bar, [alpha]m_bar, V_m_bar the patterns where unclear.
Download or read book Muscle Contraction written by Clive R. Bagshaw and published by Springer. This book was released on 1982-10-21 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: The student of biolo,gical science in his final years as an undergraduate and his first years as a graduate is expected to gain some familiarity with current research at the frontiers of his discipline. New research work is published in a perplexing diversity of publications and is inevitably concerned with the minutiae of the subject. The sheer number of research journals and papers also causes confusion and difficulties of assimilation. Review articles usually presuppose a background knowledge of the field and are inevitably rather restricted in scope. There is thus a need for short but authoritative introductions to those areas of modern biological research which are either not dealt with in standard introductory textbooks or are not dealt with in sufficient detail to enable the student to go on from them to read scholarly reviews with profit. This series of books is designed to satisfy this need. The authors have been asked to produce a brief outline of their subject assuming that their readers will have read and remembered much of a standard introductory textbook of biology. This outline then sets out to provide by building on this basis, the conceptual framework within which modern research work is progressing and aims to give the reader an indication of the problems, both conceptual and practical, which must be overcome if progress is to be maintained.
Download or read book Modeling of Excitation in Skeletal Muscle written by Sabrina Kinzie Metzger and published by . This book was released on 2021 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent experimental findings in the Rich lab suggest there are important gaps in our understanding of muscle excitability in various disease states. To generate and test hypotheses as well as to determine whether our current understanding of various aspects of muscle excitation can fully explain experimental findings, an accurate model of muscle excitation was needed. Previous studies have modeled excitation of muscle, but in each case, important aspects were omitted. One reason for this is that little effort has been made to accurately simulate muscle action potentials. In this thesis I present progress made towards generation of a model of muscle excitation that more accurately simulates experimental data than any model to date. I began by accurately simulating the spatial arrangement of t-tubules based on recent detailed imaging studies of t-tubules performed in the Voss lab. This allowed examination of whether the reduction in t-tubule diameter in muscle from a mouse model of Huntington's disease could account for the reduction in muscle capacitance. My simulations indicate the reduction in t-tubule diameter is insufficient to explain the reduction in capacitance and suggest there is an alteration of muscle membrane itself in Huntington's disease. I next derived parameters used to simulate the behavior of ion channels involved in generation of action potentials. I did this by reverse engineering the parameters from action potentials recorded in the Rich lab. The derived parameters led to more accurate modeling of action potentials than previously possible. In addition, sensitivity analysis was performed to identify the key parameters that govern action potential characteristics. Finally, I combined t-tubule geometry with the accurately simulated action potentials to explore the currently accepted idea that action potential propagation into t-tubules is necessary for the process of excitation contraction coupling. My simulations suggest action potential-induced depolarization may spread to the center of fibers intracellularly such that action potential propagation into t-tubules is not necessary for excitation contraction coupling. If true, this would be a significant departure from the current understanding of the role of t-tubules in excitation contraction coupling. My model opens the way for future studies of dysregulation of muscle excitability in a number of different muscle diseases.
Download or read book Closed Loop Control of Electrically Stimulated Skeletal Muscle Contractions written by Cheryl L. Lynch and published by . This book was released on 2011 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than one million people are living with spinal cord injury (SCI) in North America alone. Restoring lost motor function can alleviate SCI-related health problems, as well as markedly increase the quality of life enjoyed by individuals with SCI. Functional electrical stimulation (FES) can replace motor function in individuals with SCI by using short electrical pulses to generate contractions in paralyzed muscles. A wide range of FES applications have been proposed, but few application are actually available for community use by SCI consumers. A major factor contributing to this shortage of real-world FES applications is the lack of a feasible closed-loop control algorithm. The purpose of this thesis is to develop a closed-loop control algorithm that is suitable for use in practical FES applications.This thesis consists of three separate studies. The first study examined existing closed-loop control algorithms for FES applications, and showed that a method of testing FES control algorithms under realistic conditions is needed to evaluate their likely real-world performance. The second study provided such a testing method by developing a non-idealities block that can be used to modify the nominal response of electrically stimulated muscle in simulations of FES applications. Fatigue, muscle spasm, and tremor non-idealities are included in the block, which allows the user to specify the severity level for each type of non-ideal behaviour. This non-idealities block was tested in a simulation of electrically induced knee extension against gravity, and showed that the nominal performance of the controllers was substantially better than their performance in the realistic case that included the non-idealities model. The third study concerned the development and testing of a novel observer-based sliding mode control (SMC) algorithm that is suitable for use in real-world FES applications. This algorithm incorporated a fatigue minimization objective as well as co-contraction of the antagonist muscle group to cause the joint stiffness to track a desired value. The SMC algorithm was tested in a simulation of FES-based quiet standing, and the non-idealities block was used to determine the probable performance of the controller in the real world. This novel controller performed very well in simulation, and would be suitable for use in selected practical FES applications. The work contained in this thesis can easily be extended to a wide range of FES applications.This work represents a significant step forward in closed-loop control for FES applications, and will facilitate the development of sophisticated new electrical stimulation systems for use by consumers in their homes and communities.
