Design and Construction of a Prototype Tensegrity Structure with Integrated Pretensioning and Instrumentation Features

Tensegrity structures have developed greatly in recent years due to their unique mechanical, structural, and mathematical properties. This study presents the design and fabrication of a tensegrity structure prototype. A pretensioning device is designed, and it is directly integrated into the tension element. This component enables precise application and regulation of cable pretension. Another instrumentation device was designed to enable internal force monitoring during structural testing. A physical prototype of the second member of the Octahedron family, known as the expanded octahedron, was constructed using 1 m long steel struts with a rigid auxiliary support frame specifically designed for this purpose. This frame allows the geometry of the tensegrity structure to be controlled at any stage of the fabrication process, and it proved highly effective—maximum nodal displacements were restricted to ±0.4 mm, and the final prestress state in all 24 cables was achieved within a tight tolerance of ±5% (i.e., 600 ± 30 N). This paper provides an essential methodological reference for the structure’s fabrication and assembly, supporting future experimental analysis of its mechanical response.