A Bond Graph Approach to the Analysis of Prosthesis for a Partially Impaired Hand

2006 ◽  
Vol 129 (1) ◽  
pp. 105-113 ◽  
Author(s):  
Anand Vaz ◽  
Shinichi Hirai
Keyword(s):  
Bond Graph ◽  
Relative Orientation ◽  
Bond Graphs ◽  
Graph Models ◽  
Prosthetic Devices ◽  
Actuation Mechanism ◽  
Prosthetic Joints ◽  
System Equations ◽  
Analysis Of Dynamics ◽  
Prosthetic Finger

A system dynamics approach, based on bond graphs, is presented for the analysis of prosthetic devices for a partially impaired hand. The partial impairment implies that the hand has lost one or more fingers but retains the ability of its remaining natural fingers. It is shown that the existing natural joints can be used for the actuation of prosthetic finger joints and enable performance of tasks that would not have been possible otherwise. This is a challenging task as motion has to be transmitted from the remaining natural joints to the prosthetic joints. The joint axes move with respect to each other during performance of tasks and do not have any fixed relative orientation. In this work, basic concepts for the actuation of the prosthesis required for such tasks are developed systematically. Based on these concepts, Bowden cable based joint actuation mechanisms for transmission of motion from natural joints to corresponding prosthetic joints are presented and analyzed. The analysis of dynamics of the resulting under-actuated prosthesis with joint actuation mechanism is based on bond graph models that are systematically developed. Using these models, system equations are derived and numerical simulations performed for the analysis. One- and two-joint actuated prototypes of the prosthesis have been presented and effectively demonstrate the proposed concepts.

scholarly journals Analysing and simulating energy-based models in biology using BondGraphTools

2021 ◽  
Author(s):  
Peter Cudmore ◽  
Michael Pan ◽  
Peter J. Gawthrop ◽  
Edmund J. Crampin
Keyword(s):  
Systems Biology ◽  
Mathematical Models ◽  
Bond Graph ◽  
Experimental Measurements ◽  
Bond Graphs ◽  
Graph Models ◽  
Conservation Of Energy ◽  
Conservation Of Mass ◽  
Physical Systems ◽  
Complex Interactions

AbstractLike all physical systems, biological systems are constrained by the laws of physics. However, mathematical models of biochemistry frequently neglect the conservation of energy, leading to unrealistic behaviour. Energy-based models that are consistent with conservation of mass, charge and energy have the potential to aid the understanding of complex interactions between biological components, and are becoming easier to develop with recent advances in experimental measurements and databases. In this paper, we motivate the use of bond graphs (a modelling tool from engineering) for energy-based modelling and introduce, BondGraphTools, a Python library for constructing and analysing bond graph models. We use examples from biochemistry to illustrate how BondGraphTools can be used to automate model construction in systems biology while maintaining consistency with the laws of physics.

Open Systems Formulation and Gaining Insight Using Lagrangian Bond Graphs

2000 ◽  
Author(s):  
Robin C. Redfield
Keyword(s):  
System Dynamics ◽  
Open Systems ◽  
Classical Method ◽  
System Modeling ◽  
Bond Graph ◽  
Small Scale ◽  
Bond Graphs ◽  
Model Modification ◽  
System Equations ◽  
Insight Into

Abstract Models of a small-scale water rocket are developed as an example of open system modeling by both the bond graph approach and a more classical method. One goal of the development is to determine the benefits of the bond graph approach into affording insight into the system dynamics. Both modeling approaches yield equivalent differential equations as they should, while the bond graph approach yields significantly more insight into the system dynamics. If a modeling goal is to simply find the system equations and predict behavior, the classical approach may be more expeditious. If insight and ease of model modification are desired, the bond graph technique is probably the better choice. But then you have to learn it!

On Gyrobondgraphs and Their Uses

1978 ◽  
Vol 100 (1) ◽  
pp. 76-82 ◽  
Author(s):  
R. C. Rosenberg
Keyword(s):  
Bond Graph ◽  
Energy Structure ◽  
Engineering Systems ◽  
Graph Models ◽  
Point Of Interest ◽  
Lumped Parameter ◽  
Lumped Parameter Models ◽  
Five Elements ◽  
System Equations ◽  
Recent Arrival

Graphical representations of lumped-parameter models for physical and engineering systems have been in use for some time. A relatively recent arrival is the bond graph, which displays energy flow and energy structure explicitly. Bond graphs are finding increasing use in a variety of applications, including classical electromechanical, hydraulic, and thermal energy systems as well as chemical and biological processes. In addition, there has been some effort to extend the approach to energy-like macroeconomic systems. The standard bond graph approach uses the same basic elements commonly found in network theory, although the graphing scheme is different. This paper defines a specific type of bond graph—the gyrobondgraph—and shows how it serves as a canonical form for a large class of lumped-parameter multiport models. The gyrobondgraph is based on only five elements and a standard graph format. A transformation procedure is described for obtaining a gyrobondgraph from a standard bond graph. The formulation of system equations associated with a gyrobondgraph is discussed briefly, and, as a point of interest, Tellegen’s Theorem in quasi-power form is derived. The gyrobondgraph appears to be an important new tool for the exploration of multiport system theory; furthermore, it is a source of new techniques for the computer simulation of bond graph models.

Application of Vector Bond Graphs to the Modeling of a Class of Hand Prostheses

Volume 3 ◽  
2004 ◽  
Author(s):  
Anand Vaz ◽  
Shinichi Hirai
Keyword(s):  
Three Dimensional ◽  
Graph Model ◽  
Systems Design ◽  
Bond Graph ◽  
Bond Graphs ◽  
Prosthetic Joints ◽  
Angular Velocities ◽  
Control Systems Design ◽  
And Control ◽  
Systematic Derivation

Vector bond graphs have been systematically applied to the modeling of prosthesis for a partially impaired hand. The partial impairment considered covers a category of the hand that has lost one or more fingers but retains the ability of its remaining natural fingers. The fingers and their prosthetic extensions are considered as rigid links. Rotation matrices which specify orientation of finger links are obtained from respective angular velocities. String-tube mechanism used to actuate prosthetic joints is modeled with the connection to joint variables of the mechanism. The vector bond graph approach enables the modeling of three dimensional movement of the hand mechanism. An example of a two joint string-tube actuated prosthetic mechanism is presented to describe the construction of the vector bond graph model. Systematic derivation of dynamics from the vector bond graphs is shown. The approach based on vector bond graphs presented here is useful for simulations and control systems design of such biomechanical systems.

Singularly Perturbed Bond Graph Models for Simulation of Multibody Systems

1995 ◽  
Vol 117 (3) ◽  
pp. 401-410 ◽  
Author(s):  
A. A. Zeid ◽  
J. L. Overholt
Keyword(s):  
Time Scale ◽  
Multibody Systems ◽  
Graph Model ◽  
Bond Graph ◽  
Rigid Bodies ◽  
Singularly Perturbed ◽  
Bond Graphs ◽  
Graph Models ◽  
Multibody Modeling ◽  
Nonlinear Properties

This paper develops a bond graph-based formalism for modeling multibody systems in a singularly perturbed formulation. As opposed to classical multibody modeling methods, the singularly perturbed formulation is explicit, which makes it suitable for modular simulation. Kinematic joints that couple rigid bodies are described by a set of differential equations with an order of magnitude smaller time scale than that of the system. Singularly perturbed models of joints can be used to investigate nonlinear properties of joints, such as clearance and friction. The main restriction of this approach is that the simulation may need to be computed using 64 bits precision because of the two-time scale nature of the solution. The formalism is based on developing bond graph models of an elementary set of graphical velocity-based constraint functions. This set can be used to construct bond graphs of any type of mechanical joint. Here, this set is used to develop bond graphs of several joints used in multibody systems and spatial mechanisms. Complex models of multibody systems may now be built by graphically concatenating bond graphs of rigid bodies and bond graphs of joints. The dynamic equations of the system are automatically generated from the resulting bond graph model. The dynamic equation derived from the bond graph are in explicit state space form, ready for numerical integration, and exclude the computationally intensive terms that arise from acceleration analysis.

scholarly journals Bond graphs and object-oriented modelling—a comparison

2002 ◽  
Vol 216 (1) ◽  
pp. 21-33 ◽  
Author(s):  
W Borutzky
Keyword(s):  
Hydraulic Drive ◽  
Object Oriented ◽  
Bond Graph ◽  
Massachusetts Institute Of Technology ◽  
Bond Graphs ◽  
Graph Models ◽  
Electrical Systems ◽  
Generalized Networks ◽  
Institute Of Technology ◽  
Object Oriented Modelling

Bond graph modelling was devised by Professor Paynter at the Massachusetts Institute of Technology in 1959 and subsequently developed into a methodology for modelling multidisciplinary systems at a time when nobody was speaking of object-oriented modelling. On the other hand, so-called object-oriented modelling has become increasingly popular during the last few years. By relating the characteristics of both approaches, it is shown that bond graph modelling, although much older, may be viewed as a special form of object-oriented modelling. For that purpose the new object-oriented modelling language Modelica is used as a working language which aims at supporting multiple formalisms. Although it turns out that bond graph models can be described rather easily, it is obvious that Modelica started from generalized networks and was not designed to support bond graphs. The description of bond graph models in Modelica is illustrated by means of a hydraulic drive. Since VHDL-AMS as an important language standardized and supported by IEEE has been extended to support also modelling of non-electrical systems, it is briefly investigated as to whether it can be used for description of bond graphs. It turns out that currently it does not seem to be suitable.

HYBRSIM—a modelling and simulation environment for hybrid bond graphs

2002 ◽  
Vol 216 (1) ◽  
pp. 35-46 ◽  
Author(s):  
P. J. Mosterman
Keyword(s):  
Numerical Analysis ◽  
Event Detection ◽  
Bond Graph ◽  
Modelling And Simulation ◽  
Simulation Environment ◽  
Dynamic Coupling ◽  
Bond Graphs ◽  
Switching Element ◽  
Graph Models ◽  
Physical Systems

Bond graphs are a powerful formalism to model continuous dynamics of physical systems. Hybrid bond graphs introduce an ideal switching element, the controlled junction, to approximate continuous behaviour that is too complex for numerical analysis (e.g. because of non-linearities or steep gradients). HYBRSIM is a tool for hybrid bond graph modelling and simulation implemented in Java and is documented in this paper. It performs event detection and location based on a bisectional search, handles run-time causality changes, including derivative causality, performs physically consistent (re-)initialization and supports two types of event iteration because of dynamic coupling. It exports hybrid bond graph models in Java and C/C++ code that includes discontinuities as switched equations (i.e. pre-enumeration is not required).

scholarly journals Simulation methods of rigid holonomic multibody systems with bond graphs

2019 ◽  
Vol 11 (3) ◽  
pp. 168781401983415 ◽  
Author(s):  
Benjamin Boudon ◽  
Thu Thuy Dang ◽  
Rebecca Margetts ◽  
Wolfgang Borutzky ◽  
François Malburet
Keyword(s):  
Software Package ◽  
Multibody Systems ◽  
Three Dimensional ◽  
Bond Graph ◽  
Compact Model ◽  
Simulation Methods ◽  
Bond Graphs ◽  
Graph Models ◽  
The Past ◽  
Practical Guidance

Bond graph software can simulate bond graph models without the user needing to manually derive equations. This offers the power to model larger and more complex systems than in the past. Multibond graphs (those with vector bonds) offer a compact model which further eases handling multibody systems. Although multibond graphs can be simulated successfully, the use of vector bonds can present difficulties. In addition, most qualitative, bond graph–based exploitation relies on the use of scalar bonds. This article discusses the main methods for simulating bond graphs of multibody systems, using a graphical software platform. The transformation between models with vector and scalar bonds is presented. The methods are then compared with respect to both time and accuracy, through simulation of two benchmark models. This article is a tutorial on the existing methods for simulating three-dimensional rigid and holonomic multibody systems using bond graphs and discusses the difficulties encountered. It then proposes and adapts methods for simulating this type of system directly from its bond graph within a software package. The value of this study is in giving practical guidance to modellers, so that they can implement the adapted method in software.

Bond Graph Models for Fluid Networks Using Modal Approximation

1985 ◽  
Vol 107 (3) ◽  
pp. 169-175 ◽  
Author(s):  
D. L. Margolis ◽  
W. C. Yang
Keyword(s):  
Transmission Lines ◽  
Bond Graph ◽  
Bond Graphs ◽  
Graph Models ◽  
Graph Representations ◽  
Approximation Techniques ◽  
Fluid Networks ◽  
Simulation Results ◽  
Dissipative Model ◽  
Modal Approximation

Modal bond graph representations of the dissipative model of rigid, cylindrical fluid transmission lines with laminar flow are developed. Modal approximation techniques are used for both hydraulic and pneumatic lines. The modeling and simulation procedures for fluid networks coupled with nonlinear and dynamic systems are greatly facilitated using bond graphs. The physical interpretation of the model is preserved in this approach. Simulation results for hydraulic single lines are compared with results derived by the quasi-method of characteristics. The simulation results for fluid networds for various line and termination configurations are illustrated.

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