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Bond graphs are a well-established technique for the modelling of complex engineering systems. The subject of this book is integrated modelling and simulation of mechatronic systems in a visual computer environment. The modelling is based on system top-down and bottom-up approach. The mathematical models are generated in a form of differential-algebraic equations solved using numerical and symbolic algebra methods. The authors carefully explain a systematic procedure for developing the models using simple visual commands and construct a bond graph at every level of decomposition. The integrated approach they develop is applied to mechanical, electrical and control systems, multibody dynamics, and continuous systems. The book contains a powerful computer simulation package on the accompanying CD-ROM. The BondSim package supports top-down and bottom-up development using component libraries.

It is known that the friction coefficient between brushes sliding against wavy copper commutator surfaces in DC machines strongly depends on pulsating current amplitude. Physical mechanisms taking place are complex and are not studied much.In this paper the rheological model of the interaction in the region of interest based on adhesive theory of friction and viscoelastic behaviour of material is proposed. As it is well known from theory of friction there is a great rise of temperature at asperitis over which a mechanical contact is taking place. The current flowing through the contact increases this temperature even more and this way influence viscoelastic properties of the contact material. Proposed model is simulated and compared with experimental results. Results shows that a model can be used as solid basis for explanation of friction behaviour of the brushes conducting current and sliding against commutator.

The effects of flow disturbances on the performance of the Coriolis mass flowmeter(CMF) with two straight parallel tubes were invetigated numerically. Two types of flow disturbances were studied numerically using the bond-graph presentation. The first one represents a local restriction in one of the pipes that causes asymmeric flow in pipes. In the second case of operating conditions, uniformly obliterated tubes were considered. The effect of the obliterated layer thickness with different densities was analysed. It was found that the local restriction at the tube entrance does not effect the sensitivity coefficient, while the flowrate in the tube changes from zero to a rate equal to that in the parallel tube. The obliteration does not effect the sensitivity coefficient either, but changes the first natural mode of tube vibration. If the CMF is used for density measurement, the obliteration may cause significant error.

This paper describes the principle of operation of the Coriolis mass flowmeter (CMF). The principle of operation is explained by means of the rotating tube after which the vibrating tube is introduced. The advantages of mass measurement over volume measurement are discussed. The most important characteristics of the CMF from different manufactures are presented. The application of the CMF in the petroleum and natural gas industry is considered and how to cope with the eventual problems is shown. Local and international recommendations and standards relevant to the CMF are cited.

The Coriolis mass flowmeter (CMF) has been increasingly used over the last two decades for liquid and gas mass flow measurements. However, performances under real installation conditions have not yet been completely investigated. This paper briefly describes the effect of flow pulsations on the sensitivity coefficient. The CMF with two parallel elastic tubes was studied based on the distributed physical model. The model is presented in the form of bond graphs. It was found that the flow pulsations with specific frequencies equal to the sum and the difference of the frequencies of the first two natural modes cause significant errors in meter reading.

In this paper the CMF with elastic parallel tubes was modelled. The tube is divided into final elements (FE), presented in the form of bond graphs and simulated by BondSim (Bondgraph Simulation System). The direct numerical integration method was applied for prediction of a time difference and other effects for the commercially available CMF. The phase or time difference was found to be proportional to the mass flow rate. The agreement between the experimental data for the given CMF with theoretical results using the equivalent length is good.

The functional representation ol engineering systems is kind of represeniation that describes how a system works, or is intended to work. It can be used for simulating and verifying design and generating diagnostics. A new automated modelling approach is developed to address these issues. Modelling of a system is based on system decomposition. Band Graphs and Block Diagrams were chosen as model representation language. The basic item of a model is a component represented as an object which contains all information on its properties and behaviour. Editing of the model is made in a user friendly visual environment. The models are held in database which supports common model management operations. The study of the system behaviour can be conducted by simulation. Prior to sirnulation the model is to be processed. Integration of system equations was provided by suitable differential algebraic equation solver. The approach is applied to modelling and simulation of a robot system.

In this paper a unified approach to the analysis of Coriolis mass flowmeter and a fluid angular rate sensor has been presented. A new type of the fluid angular rate sensor is proposed. The operation of both sensors has been mathematically modelled. The system of equations was solved by the bond graph method using BondSim. The method of solution permits simulation of the complex metering systems. The results of simulation for the Coriolis mass flowmeter showed the linear relationship between the mass flow rate and the time difference of reference signals. In the simplest case of the angular rate sensor with the circulating flow the tube deformation was proportional to the angular rate.

Modelling has been traditionally regarded as a manual task. As such it has many drawbacks. Automated modelling is a research field developed to improve the model building process and to reduce human involvement. In this paper an automated modelling systems approach is given. Modelling of a system is based on system decomposition. Bond graphs and block diagrams were chosen as the model representation language. The basic item of a model is a component represented as an entity that contains all the information on its structure, properties and behaviour. Editing of the model is done in a user friendly visual environment. The models are held in a database which supports common model management operations. The study of the system behaviour can be conducted by simulation. The approach has been applied to the modelling and simulation of internal combustion engines.

In the first part an experimental investigation has been conducted to determine behaviour of the friction coefficient during transient conditions. Using results of the experimental investigation, a dynamic model of the friction process has been developed that help to predict behaviour of friction coefficient of brushes under real working conditions. The process has been simulated using bond graph modeling approach. The results of simulation are in good agreement with experimental results (under 5%).

In this paper the operation of fluid angular rate sensors (FARS) has been analysed. The fluid flow circuits have been proposed. The mathematical model was developed and discretized using the final element approach. The sensor is presented in the form of bond graphs and the mathematical model solved using RondSim (Microsoft-Windows based simulation program) The sensors with steady and oscillating flows were analysed. There were found the linear relationships between the input angular rate and tube deformation for wide range of input change.

The research reported in this paper represent the continuation of the revious work on the problem of the friction coefficient of brushes under a pulsating current. In the first part and experimental investigation has been conducted to determine the behaviour of the friction coefficient during transient conditions. Using the results of the experimental investigations, a dynamic model of the friction process has been developed that helps to predict behaviour of the friction coefficient of brushes under real working conditions. The process has been simulated using a bond graph based modelling approach.

This paper focuses on bond graph modelling of robot system based on bond graph approach. Problem that was addressed is dynamic of constrained motion of robots under hybrid control low. Model developed includes detailed description of both the system and environment as hierarchical multilevel model. Mathematical model was generated in the form of differential-algebraic system that was successfully solved. It was shown that bond graphs can be successfully used for solution of problems in robot dynamics and control.

An approach to simulation of mechanical system using bond graphs is presented. The mechanical system may consist of several rigid bodys connected by joints. Modelling of such a system can be developed by system decomposition. At each level of decomposition processes considered were described using bond graphs. In that way model of the system has been represented as a tree of models. Models in the tree represent objects that contain all informations on its functionality. The bond graph used are acausal not implying any specific input-output relationships. Description of the system motion apears as a system of the sparse nonlinear differention formula.The approach has been applied to simulation of the motion of the reciprocating mechanism.

In essence modelling of an engineering system consists of analysing the system and its environment, decomposing it on components, stating modelling hypothesis and representation of resulting model. Bond graphs are well suited for representation of physical processes in engineering systems. Word models with explicit defined ports can be used for representation of models as power and information exchanging objects. Using object programming approach in a visual environment enable systematic computer assisted decomposition, generation of system and component model libraries, and reuse of models in building up of new models. Models developed can be further parsed and corresponding simulation model can be created for execution of corresponding simulation experiments.