An Active Deployable Tensegrity-Ring Footbridge System

Structural engineering is evolving towards tuned performance structures through the integration of active control. Tensegrity structures are cable-truss structures that can combine actuators, sensors and structural elements. A tensegrity-ring system that has been found viable for an active deployable footbridge application is presented in this paper. Active cables are employed to simultaneously adjust several degrees of freedom and enhance performance through independent actuation. Numerical results were validated experimentally on a near-full-scale actively controlled physical model. However, predefined actuation steps do not always result in the same position. Therefore, the configuration of the model is improved through a sequence of correction-control commands that are tested and selected according to direct measurements. The two-stage strategy is able to generate effective cable actuation for the mid-span connection of the deployable tensegrity-ring footbridge system and it is likely to be applicable for a range of complex structures where exact modelling of true behavior is difficult.