Constructions primarily made from a grid of rods play an important role in the production of structures, such as bridges, and large technical appliances, such as cranes. A clever arrangement of the supports make it possible to construct large spatial structures whilst maintaining a low material weight. A favourable distribution of tensile and compressive stress between the load and the material weight are important planning goals. In der animation, these forces are visualised through colour changes, using the example of a simple bridge construction. In this way, one can identify the parts of the construction, which carry the greatest burden.