System Specification by Linear Graph

A mechanical translational system with vibration absorbing elements, driven by a force source,  is shown below, along with its linear graph representation:

In the Maple-SYREP screen below, the elements are specified by their connection between the numbered nodes on the linear graph.  For example there is a viscous damper element, with viscous coefficient B2, connected between nodes 1 and 2, and it is specified as the list [1,2,damper,B2].  SYREP contains a "dictionary" of known energy storage and dissipative elements in several domains.  The procedure "LGraph_to_system" takes the lists of elements and output variables and  generates an internal system "object" in state-space form (in this case named "damped_system") from the graph structure.  

Notice that SYREP has chosen the state variables to be the power variables associated with energy storage elements (velocities of masses, and forces on springs in this case).  In the bottom part of the screen, values are assigned to the system elements and the system step response is computed.