Mid-span connection of a deployable tensegrity footbridge

This paper describes a near full-scale deployable tensegrity footbridge. Tensegrity structures are pre-stressed structures composed of tension elements (cables) surrounded by compression elements (struts) in equilibrium. Deployment of two bridge halves is assisted by the energy stored in spring elements. Five active cables control the deployment of each half. This paper presents a two-stage control methodology for determining control commands for mid-span connection of the two bridge halves. The control methodology determines active cable length changes based on computational control on a simplified analytical model and including measurement of the structural response to cable-length changes. Both halves are successfully connected at the end of deployment. Active control strategies provide effective solutions for completing deployment of multi-degree-of-freedom structures.