FAIRDO BG example 3.2.cellml

Bond graph example: A mechanical system

Here we show a simple mechanical system with a spring for static energy storage (compliance C), a mass (L) for dynamic (inertial) energy storage, and a damper (R) for dissipating energy. The potentials umC, umR, umL (superscript ‘m’ for ‘mechanical’) are now the mechanical forces and the flow vm1 is the velocity of the displacement qm1. i.e., vm1 = (dqm1) ⁄ dt. There is one common point where energy is balanced (the 1:node) and in this system there is no need for a 0:node for mass conservation.

Schematic and bond graph of the model

A simple mechanical system (a) with spring C, damper R and mass L, and its bond graph representation (b). In this case the 1:node represents the physical point (indicated by the dotted line) at which energy is balanced (forces in equilibrium). Since there is only one displacement and hence flow (velocity) term, no 0:nodes are required.

The Views Available menu to the right provides various options to explore this model here in the Physiome Model Repository. Of particular interest is the Launch with OpenCOR menu item, which will load the simulation experiment shown below directly into the OpenCOR desktop application.

OpenCOR showing simulation experiment.

Showing the result of launching the simulation experiment from this exposure in OpenCOR and executing the simulation.