Force Chains

hello
I noticed that in the Tools folder of ESyS-Particle2.1 tree there is a folder called "ForceChains".
 i wanna know how to use it .
 i want to output forcechian graph by using paraview, and how to get a vtkfile about forcechain?
 I added the following code (#92702)to my simulation:
sim.createFieldSaver (
    InteractionVectorFieldSaverPrms (
       interactionName="friction",
       fieldName="force",
       fileName="force_data",
       fileFormat="RAW2",
       beginTimeStep=0,
       endTimeStep=100000,
       timeStepIncr=1
    )
 )
and then using the following command line(#91547) to get a vtk file
fcconv -i <input file name> -o <output file name> -vtk
but it doesn't work.
tks