This paper introduces a webbased interactive educational platform for 3D/polyhedral graphic statics (PGS) [1]. The Block Research Group (BRG) at ETH Zürich developed a dynamic learning and teaching platform for structural design. This tool is based on traditional graphic statics. It uses interactive 2D drawings to help designers and engineers with all skill levels to understand and utilize the methods [2]. However, polyhedral graphic statics is not easy to learn because of its characteristics in threedimensional. All the existing computational design tools are heavily dependent on the modeling software such as Rhino or the Pythonbased computational framework like Compass [3]. In this research, we start with the procedural approach, developing libraries using JavaScript, Three.js, and WebGL to facilitate the construction by making it independent from any software. This framework is developed based on the mathematical and computational algorithms deriving the global equilibrium of the structure, optimizing the balanced relationship between the external magnitudes and the internal forces, visualizing the dynamic reciprocal polyhedral diagrams with corresponding topological data. This instant opensource application and the visualization interface provide a more operative platform for students, educators, practicers, and designers in an interactive manner, allowing them to learn not only the topological relationship butmore »
Developing a polyhedral graphic statics formulation for tetrahedral truss systems
This paper presents procedures to generate truss topologies as an input form for polyhedral graphic statics and develops an algebraic formulation to construct their force diagrams. The study's ultimate goal is to extend the authors' previous research in 2D [1] to generate 3D strutandtie models and stress fields for reinforced concrete design. The recent algebraic formulation constructs reciprocal polyhedral diagrams of 3D graphic statics with either form or force as input [2]. However, the input is usually a set of polyhedrons or selfstressed networks [3]. Another implementation of polyhedral graphic statics [4] includes general truss topologies. But the starting geometry is usually the global force diagram, and based on its modification or subdivision, a form diagram is constructed. Therefore, currently, there exists no formulation to analyze a spatial truss using polyhedral graphic statics.
This paper develops an algorithm to build upon the algebraic 3D graphic statics formulation and notation [2, 5] to construct the force diagram for input geometries that do not include all closed cells. The article also shows how the proper definition of the external spaces between the applied loads and reaction forces and the tetrahedral subdivision of the truss makes it possible to construct the reciprocal force diagram. more »
 Award ID(s):
 1944691
 Publication Date:
 NSFPAR ID:
 10209910
 Journal Name:
 International Association of Shell and Spatial Structures
 Sponsoring Org:
 National Science Foundation
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