scholarly journals Validation of the Inverse Dynamic Analysis of Human Gait Using a Forward Dynamics Approach

2013 ◽  
Author(s):  
Rosa Pàmies-Vilà ◽  
Josep M. Font-Llagunes
Keyword(s):  
Dynamic Analysis ◽  
Degrees Of Freedom ◽  
Inverse Dynamics ◽  
Human Gait ◽  
Intermediate Step ◽  
Inverse Dynamic ◽  
Joint Forces ◽  
Simulated Motion ◽  
Dynamical Consistency ◽  
Inverse Dynamics Analysis

One of the aims of the dynamic analysis of human gait is to know the joint forces and torques that the musculoskeletal system produces during the motion. For this purpose, an 18 segment 3D model with 57 degrees of freedom is implemented. The analysis of a captured motion can be addressed by means of forward or inverse dynamic analyses. In this work, both analyses are computed using multibody dynamics techniques. The forward dynamic analysis is carried out with the aim of simulating the movement of the multibody system using the results of the inverse problem as input data. Since the inverse analysis is solved using a dynamically consistent methodology, the forward dynamic analysis allows us to simulate up to the 90% of the gait cycle without any controller. After that, a proportional derivative (PD) controller is implemented to stabilize the system, which gets to simulate the complete captured motion. Moreover, the dynamic contribution of the controller is really low and the simulated motion is extremely close to the original one. The methodology presented allows us to validate the correctness of the inverse dynamics analysis and it is an intermediate step towards the prediction problem: it requires dynamical consistency too, but the uncertainties involved in the problem are lower than in a predictive approach.

Virtual Design and Inverse Dynamics Analysis of Aircraft Taxi-Mover Lifting Unit

2011 ◽  
Vol 121-126 ◽  
pp. 1545-1549
Author(s):  
Xu Dong Shi ◽  
Shou Wen Shi ◽  
Jian Li Li
Keyword(s):  
Dynamic Analysis ◽  
Inverse Dynamics ◽  
Dynamics Analysis ◽  
Virtual Design ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis ◽  
Parameterized Model ◽  
Inverse Dynamics Analysis

A new holding-lifting autosteer mechanism (HAM) is introduced which is fit for aircraft taxi-mover. The relation between the Multi-bar mechanism and tug operation of the aircraft on the taxiway is also discussed. With this understanding , a virtual parameterized model of holding-lifting autosteer mechanism is established by Pro/E . Based on Single-opened-chain , inverse dynamic analysis for planar parallel lifting unit is presented .

Inverse Dynamic Analysis and Linearisation of a High Speed Parallel Mechanism

2005 ◽  
Author(s):  
M. Necip Sahinkaya ◽  
Yanzhi Li
Keyword(s):  
Dynamic Analysis ◽  
Parallel Mechanism ◽  
High Speed ◽  
Inverse Dynamics ◽  
Motion Path ◽  
Model Parameters ◽  
Control Input ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis ◽  
Dynamics Models

Inverse dynamic analysis of a three degree of freedom parallel mechanism driven by three electrical motors is carried out to study the effect of motion speed on the system dynamics and control input requirements. Availability of inverse dynamics models offer many advantages, but controllers based on real-time inverse dynamic simulations are not practical for many applications due to computational limitations. An off-line linearisation of system and error dynamics based on the inverse dynamic analysis is developed. It is shown that accurate linear models can be obtained even at high motion speeds eliminating the need to use computationally intensive inverse dynamics models. A point-to-point motion path for the mechanism platform is formulated by using a third order exponential function. It is shown that the linearised model parameters vary significantly at high motion speeds, hence it is necessary to use adaptive controllers for high performance.

scholarly journals Control of the boundary conditions of a dynamic knee simulator

2015 ◽  
Vol 6 (2) ◽  
pp. 7 ◽  
Author(s):  
Jan Tiré ◽  
Jan Victor ◽  
Patrick De Baets ◽  
Matthias Verstraete
Keyword(s):  
Boundary Conditions ◽  
Dynamic Analysis ◽  
Ankle Joint ◽  
Hip Joint ◽  
Degrees Of Freedom ◽  
Muscle Forces ◽  
Inverse Dynamic ◽  
Human Knee ◽  
Inverse Dynamic Analysis ◽  
Knee Simulator

At Ghent University a dynamic knee simulator to analyse the kinematics of a human knee has been developed. The rig is designed to perform tests on a mechanical hinge or on a human knee (with or without a prosthesis). The rig has one degree of freedom in a hip joint and four degrees of freedom in an ankle joint. There is currently one actuator that simulates the quadriceps forces. Two additional actuators are proposed in this paper to simulate the hamstrings forces. The magnitude and phase of the forces varies significantly during the movement (e.g. cycling or squatting). Literature indicates that the maximum muscle forces do not exceed 2000 N. An inverse dynamic analysis, using the musculoskeletal software AnyBody, is proposed to determine the evolution of these forces during the studied movements.

Influence of Modern Studded and Bladed Soccer Boots and Sidestep Cutting on Knee Loading during Match Play Conditions

2007 ◽  
Vol 35 (9) ◽  
pp. 1528-1536 ◽  
Author(s):  
Rajiv Kaila
Keyword(s):  
Inverse Dynamics ◽  
Cruciate Ligament ◽  
Three Dimensional ◽  
Match Play ◽  
Joint Forces ◽  
Significant Difference ◽  
Knee Loading ◽  
Anterior Cruciate ◽  
Inverse Dynamics Analysis ◽  
Straight Ahead

Background The influence of modern studded and bladed soccer boots and sidestep cutting on noncontact knee loading during match play conditions is not fully understood. Hypothesis Modern soccer boot type and sidestep cutting compared with straight-ahead running do not significantly influence knee internal tibia axial and valgus moments, anterior joint forces, and flexion angles. Study Design Controlled laboratory study. Methods Fifteen professional male outfield soccer players undertook trials of straight-ahead running and sidestep cutting at 30° and 60° with a controlled approach velocity on a Fédération Internationale de Football Association (FIFA) approved soccer surface. Two bladed and 2 studded soccer boots from 2 manufacturers were investigated. Three-dimensional inverse dynamics analysis determined externally applied internal/external tibia axial and valgus/varus moments, anterior forces, and flexion angles throughout stance. Results The soccer boot type imparted no significant difference on knee loading for each maneuver. Internal tibia and valgus moments were significantly greater for sidestep cutting at 30° and 60° compared with straight-ahead running. Sidestep cutting at 60° compared with straight-ahead running significantly increased anterior joint forces. Conclusion Varying soccer boot type had no effect on knee loading for each maneuver, but sidestep cutting significantly increased internal tibia and valgus moments and anterior joint forces. Clinical Relevance Sidestep cutting, irrespective of the modern soccer boot type worn, may be implicated in the high incidence of noncontact soccer anterior cruciate ligament injuries by significantly altering knee loading.

Estimation of Metabolical Costs for Human Locomotion

2005 ◽  
Author(s):  
Werner Schiehlen ◽  
Marko Ackermann
Keyword(s):  
Degrees Of Freedom ◽  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Human Locomotion ◽  
Human Gait ◽  
Joint Torques ◽  
Gait Quality ◽  
Analysis Laboratory ◽  
Muscle Models

Metabolical energy is the chemical energy consumed by skeletal muscles to generate force. This quantity is useful to understand the comfort of human gait and to evaluate, in terms of effort required, the performance of devices or therapies designed to improve gait quality of persons presenting gait disorders. Firstly, this paper presents the frequently used estimations of energy expenditure based lonely on joint torques and mechanical costs obtained by inverse dynamics of passive and active walking devices. Secondly, a more advanced approach is discussed consisting of modeling the musculoskeletal system with Hill-type phenomenological muscle models and computing the metabolical expenditure adopting expressions recently proposed in the literature. As an example a musculoskeletal model of the lower limb in the sagittal plane consisting of thigh, shank and foot with three degrees of freedom and actuated by eight muscles is considered. This model is used to estimate metabolical costs for known normal gait kinematical data obtained in a gait analysis laboratory.

scholarly journals Musculoskeletal Analysis of Driving Fatigue: The Influence of Seat Adjustments

2013 ◽  
Vol 10 ◽  
pp. 373-378 ◽  
Author(s):  
Noor Aliah binti Abdul Majid ◽  
Mohd Fareez Edzuan Abdullah ◽  
Mohd Syahmi Jamaludin ◽  
Mitsuo Notomi ◽  
John Rasmussen
Keyword(s):  
Human Body ◽  
Degrees Of Freedom ◽  
Muscle Activation ◽  
Inverse Dynamics ◽  
Spring Stiffness ◽  
Car Seat ◽  
Joint Forces ◽  
Rigid Body Model ◽  
Driving Fatigue ◽  
Anybody Modeling System

Main causes for discomfort experienced by vehicle drivers during driving were investigated using a rigid-body model originally developed in the AnyBody Modeling System [. The interactions between the human body and the car-seat in various combinations of seat-pan/backrest inclinations and the effect of pedal spring stiffness were analyzed using an inverse dynamics approach. To deal with the muscle redundancy problem, (i.e. the problem with the human-body containing more muscles than necessary to drive its degrees of freedom) a minimum-fatigue criterion [ was utilized. The results show that various seat adjustments (e.g., seat-pan and backrest inclinations) and the pedal spring stiffness have complex influences on the muscle activation and spinal joint forces of the human body. From the results, an optimal adjustment for the car-seat is proposed, i.e. the backrest inclination is 10° and the seat-pan inclination is between 0o to 5 o. This study can in general capture the overall interactions between human body and environment (i.e. the maximum muscle activity and spine forces), which is thought to be the factors of driving fatigue.

FEM Based Numerical Simulation of Delta Parallel Mechanism

2013 ◽  
Vol 690-693 ◽  
pp. 2978-2981 ◽  
Author(s):  
Jian Zhong Zhang ◽  
Xin Peng Xie ◽  
Chuan Jin Li ◽  
Ying Ying Xin ◽  
Zhao Ming He
Keyword(s):  
Inverse Kinematics ◽  
Degrees Of Freedom ◽  
Inverse Dynamics ◽  
Theoretical Foundation ◽  
Future Research ◽  
Element Analysis ◽  
Pick And Place ◽  
Integral Structure ◽  
Inverse Dynamics Analysis ◽  
Three Degrees Of Freedom

This paper describes a parallel three degrees of freedom delta mechanism used for pick-and-place. It has the advantages of simple integral structure, strong bearing capacityhigh precisionkinematics and dynamics performance. According to this mechanism wide development prospect, the company study on the inverse kinematics inverse dynamics analysis and the static analysis by using ANSYS finite element analysis Software of Delta. These analyses have laid a good theoretical foundation for future research. These researches provide possible for widely used in foodpackingautomated assembly line occasions of small and medium-sized enterprises.

Analysis of different uncertainties in the inverse dynamic analysis of human gait

2012 ◽  
Vol 58 ◽  
pp. 153-164 ◽  
Author(s):  
Rosa Pàmies-Vilà ◽  
Josep M. Font-Llagunes ◽  
Javier Cuadrado ◽  
F. Javier Alonso
Keyword(s):  
Dynamic Analysis ◽  
Human Gait ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis

Three-Dimensional Knee Joint Loading in Alpine Skiing: A Comparison Between a Carved and a Skidded Turn

2012 ◽  
Vol 28 (6) ◽  
pp. 655-664 ◽  
Author(s):  
Miriam Klous ◽  
Erich Müller ◽  
Hermann Schwameder
Keyword(s):  
Knee Joint ◽  
Inverse Dynamics ◽  
Small Sample Size ◽  
Three Dimensional ◽  
Small Sample ◽  
High Rate ◽  
Joint Loading ◽  
Joint Forces ◽  
Inverse Dynamics Analysis ◽  
Knee Joint Loading

Limited data exists on knee biomechanics in alpine ski turns despite the high rate of injuries associated with this maneuver. The purpose of the current study was to compare knee joint loading between a carved and a skidded ski turn and between the inner and outer leg. Kinetic data were collected using Kistler mobile force plates. Kinematic data were collected with five synchronized, panning, tilting, and zooming cameras. Inertial properties of the segments were calculated using an extended version of the Yeadon model. Knee joint forces and moments were calculated using inverse dynamics analysis. The obtained results indicate that knee joint loading in carving is not consistently greater than knee joint loading in skidding. In addition, knee joint loading at the outer leg is not always greater than at the inner leg. Differentiation is required between forces and moments, the direction of the forces and moments, and the phase of the turn that is considered. Even though the authors believe that the analyzed turns are representative, results have to be interpreted with caution due to the small sample size.

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