3D Graphic Statics by Ognjen Graovac is a structural form-finding method for generating compression-only spatial forms. This plug-in has been developed for Grasshopper. In 3D graphic statics, the static equilibrium of structures is described by using two reciprocal diagrams and their geometric relationship – form and force.

The change in one diagram will affect the geometry in other. Therefore, designers have direct control over the form and the forces at the same time. In short, the force diagram is represented as a set of closed convex polyhedral cells, and each polyhedron represents one node (within the form diagram).

Two polyhedral cells sharing the same brep face are equal to two adjacent nodes, interconnected by the rod. The intensity of the force in the rod is proportional to the area of the brep face, while the orientation is generated iteratively until its direction coincides with the normal vector of the face.

The main goal of developing this tool was to automate the process of generating force diagrams, to rapidly examine different design solutions as well as to explore the possibilities of connecting 3D Graphic Statics with other Grasshopper tools. The plug-in provides components for subdividing polyhedral cells, form-finding processes, computing forces, generating cross sections, etc.

With this digital tool architects, engineers, students and researchers can create a parametrically driven system that can generate optimal structures of a particular aesthetics. This tool has been developed for future academic research. Most of the algorithms are based on the scientific articles done by Block Research Group (http://www.block.arch.ethz.ch/brg/research).