Hi, the paper "Multi-Scale Modeling of Tissues Using CompuCell3D" says, "The fixed discretization makes explicit modeling of fibers or membranes expensive, since the lattice constant must be set to the smallest scale to be explicitly represented. Cell membrane fluctuations are also caricatured as a result of the fixed spatial resolution. However, the latest versions of CC3D support a layer of finite-element links which have length but zero diameter. These can be used to represent fibers or membranes, allowing a simulation to combine the advantages of both methods at the cost of increased model complexity." How to realize it?
The layer fo finite-element-like links is essentially Focal Point Plasticity. It places a constraint on the distance between two centers of masses of the two cells. For example you can have a compartmentalized cell composed of many compartments and you can connect "outermost" compartments with a series of focal point plasticity links. This could provide contractile force, of similar type as membrane would exert.