Human movement is the result of a complex and synergistic interaction between the musculoskeletal and the central nervous system. As result, muscles contract coordinately to produce forces that are transmitted by tend...
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ISBN:
(纸本)9783319306148;9783319306124
Human movement is the result of a complex and synergistic interaction between the musculoskeletal and the central nervous system. As result, muscles contract coordinately to produce forces that are transmitted by tendons to the skeletal system, causing its movement or keeping its pose. Often neglected in current muscle models, the elastic properties of tendons play a significant role in the dynamic interaction between the muscular and skeletal systems, influencing the force transmission, energy storage and transfer, and joint control. The aim of this work is to present in detail the necessary steps to incorporate a musculotendon model in the framework of a multibody systems dynamics formulation. A methodology to compute the musculotendon forces and activations is presented based on the use of a Hill-type muscle model assembled in series with a spring-like element defined according to the elastic properties of the tendon. The proposed methodology can be applied, without significant changes, to both inverse and forward dynamic analyses of biomechanical systems. Three daily activities with different levels of musculotendon recruitment are analyzed from an inverse dynamics perspective. The selected activities are walking, running and jumping. The movement data characterizing these activities were acquired experimentally in a movement laboratory. A 3D biomechanical model of the human body, described with natural coordinates and encompassing 43 musculotendon actuators per leg, is proposed to assess the performance of the presented musculotendon model and of its incorporation on the referred multibody dynamics framework. The influence of the introduction of a compliant tendon model on the produced muscle forces and activation patterns is analyzed in face of those same results produced by the same biomechanical model defined with infinitely stiff (or rigid) tendons. Results revealed that the introduction of the tendon model allows muscles to work, predominantly, on their op
The scope of the present contribution is the derivation of the equations of motion and its field of application for humanoid robots, in particular legged robots. The derivation is performed in a modular and structured...
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ISBN:
(纸本)9783319306148;9783319306124
The scope of the present contribution is the derivation of the equations of motion and its field of application for humanoid robots, in particular legged robots. The derivation is performed in a modular and structured manner and it is shown how these equations can be exploited for the control of biped robots. The used methods allow to easily adopt the kinematic structure of single limbs and to reuse results obtained for limbs with similar kinematic structure but different inertial parameters such as in case the left leg is a mirrored version of the right one. After finding a recursive formulation to calculate the equations of motion we perform various state transformations and apply some model simplifications to obtain expressions that can be used to efficiently solve control problems. Two applications, compensating for the overall angular momentum and calculation of feed-forward torques, are shown. In both applications we can exploit the recursive calculation of the equations of motion used during the subsystem synthesis giving rise to real-time algorithms that can be used on a physical humanoid robot system.
A comprehensive analysis on the use of different friction force models on the dynamic simulations of multibody mechanical systems is investigated in this work. In this context, some of the most relevant approaches for...
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ISBN:
(纸本)9783319306148;9783319306124
A comprehensive analysis on the use of different friction force models on the dynamic simulations of multibody mechanical systems is investigated in this work. In this context, some of the most relevant approaches for dealing with friction available in the literature are revisited. In a broad sense, the friction models can be classified into the statics and dynamics models, as they describe the steady-state behavior or utilize extra state variable to capture the dynamic phenomena, respectively. In this process, the main limitations and implications of the friction force models are briefly analyzed. The dynamic responses of a single-mass one degree-of-freedom system with permanent contact, as well as a multibody model of double pendulum impacting the ground at its tip, are examined to analyze and compare the various friction laws. The obtained results suggest that the prediction of the dynamic behavior of multibody systems can strongly depend on the selection of the appropriate friction model as well as frictional parameters.
This volume contains selected papers in three closely related areas: mathematical modeling in mechanics, numerical analysis, and optimization methods. The papers are based upon talks presented on the International Con...
ISBN:
(纸本)331923563X;9783319235639
This volume contains selected papers in three closely related areas: mathematical modeling in mechanics, numerical analysis, and optimization methods. The papers are based upon talks presented on the International Conference for Mathematical Modeling and Optimization in Mechanics, held in Jyvskyl, Finland, March 6-7, 2014 dedicated to Prof. N. Banichuk on the occasion of his 70th birthday. The articles are written by well-known scientists working in computational mechanics and in optimization of complicated technical ***, the volume contains papers discussing the historical development, the state of the art, new ideas, and open problems arising in modern continuum mechanics and applied optimization problems. Several papers are concerned with mathematical problems in numerical analysis, which are also closely related to important mechanical models. The main topics treated include:* Computer simulation methods in mechanics, physics, and biology;* Variational problems and methods; minimization algorithms;* Optimal control problems with distributed and discrete control;* Shape optimization and shape design problems in science and engineering;* Sensitivity analysis and parameters optimization of complex systems.
This book assembles, identifies and highlights the most recent developments in Rehabilitation and retrofitting of historical and heritage structures. This is an issue of paramount importance in countries with great bu...
ISBN:
(数字)9783319161297
ISBN:
(纸本)9783319161297;9783319161303
This book assembles, identifies and highlights the most recent developments in Rehabilitation and retrofitting of historical and heritage structures. This is an issue of paramount importance in countries with great built cultural heritage that also suffer from high seismicity, such as the countries of the eastern Mediterranean basin. Heritage structures range from traditional residential constructions to monumental structures, ancient temples, towers, castles, etc. It is generally recognized that these structures present particular difficulties in seismic response calculation through computer simulation due to the complexity of the structural system which is, generally, inhomogeneous, with several contact problems, gaps/joints, nonlinearities and brittleness in material constituents. This book contains selected papers from the ECCOMAS Thematic Conferences on computationalmethods in Structural Dynamics & Earthquake Engineering (COMPDYN) that were held in Corfu, Greece in 2011 and Kos, Greece in 2013. The Conferences brought together the scientific communities of computational Mechanics, Structural Dynamics and Earthquake Engineering in an effort to facilitate the exchange of ideas in topics of mutual interest and to serve as a platform for establishing links between research groups with complementary activities.
This book focuses on civil and structural engineering and construction management applications. The contributions constitute modified, extended and improved versions of research presentedat the minisymposium organized...
ISBN:
(数字)9783319204062
ISBN:
(纸本)9783319204055;9783319204062
This book focuses on civil and structural engineering and construction management applications. The contributions constitute modified, extended and improved versions of research presentedat the minisymposium organized by the editors at the ECCOMAS conference on this topic in Barcelona 2014.
The chapters which appear in this volume are selected studies presented at the First International Conference on Engineering and appliedsciences Optimization (OPT-i), Kos, Greece, 4-6 June 2014 and works written by f...
ISBN:
(数字)9783319183206
ISBN:
(纸本)9783319183190;9783319183206
The chapters which appear in this volume are selected studies presented at the First International Conference on Engineering and appliedsciences Optimization (OPT-i), Kos, Greece, 4-6 June 2014 and works written by friends, former colleagues and students of the late Professor M. G. Karlaftis; all in the area of optimization that he loved and published so much in himself. The subject areas represented here range from structural optimization, logistics, transportation, traffic and telecommunication networks to operational research, metaheuristics, multidisciplinary and multiphysics design optimization, *** volume is dedicated to the life and the memory of Professor Matthew G. Karlaftis, who passed away a few hours before he was to give the opening speech at OPT-i. All contributions reflect the warmth and genuine friendship which he enjoyed from his associates and show how much his scientific contribution has been appreciated. He will be greatly missed and it is hoped that this volume will be received as a suitable memorial to his life and achievements.
This volume contains thirteen articles on advances in applied mathematics and computing methods for engineering problems. Six papers are on optimization methods and algorithms with emphasis on problems with multiple c...
ISBN:
(数字)9789401790543
ISBN:
(纸本)9789401790536
This volume contains thirteen articles on advances in applied mathematics and computing methods for engineering problems. Six papers are on optimization methods and algorithms with emphasis on problems with multiple criteria; four articles are on numerical methods for applied problems modeled with nonlinear PDEs; two contributions are on abstract estimates for error analysis; finally one paper deals with rare events in the context of uncertainty quantification. Applications include aerospace, glaciology and nonlinear elasticity. Hereinis a selection of contributions from speakers at two conferences on applied mathematics held in June 2012 at the University of Jyvskyl, Finland. The first conference, Optimization and PDEs with Industrial Applications celebrated the seventieth birthday of Professor Jacques Priaux of the University of Jyvskyl and Polytechnic University of Catalonia (Barcelona Tech) and the second conference, Optimization and PDEs with Applications celebrated the seventy-fifth birthday of Professor Roland Glowinski of the University of Houston. This work should be of interest to researchers and practitioners as well as advanced students or engineers in computational and applied mathematics or mechanics.
This book presents and discusses mathematical models, numerical methods and computational techniques used for solving coupled problems in science and engineering. It takes a step forward in the formulation and solutio...
ISBN:
(数字)9783319061368
ISBN:
(纸本)9783319061368
This book presents and discusses mathematical models, numerical methods and computational techniques used for solving coupled problems in science and engineering. It takes a step forward in the formulation and solution of real-life problems with a multidisciplinary vision, accounting for all of the complex couplings involved in the physical description. Simulation of multifaceted physics problems is a common task in applied research and industry. Often a suitable solver is built by connecting together several single-aspect solvers into a network. In this book, research in various fields was selected for consideration: adaptive methodology for multi-physics solvers, multi-physics phenomena and coupled-field solutions, leading to computationally intensive structural analysis. The strategies which are used to keep these problems computationally affordable are of special interest, and make this an essential book.
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