Tensegrity Active Control: Multiobjective Approach

Abstract

A multiobjective search method is adapted for supporting structural control of an active tensegrity structure. Structural control is carried out by modifying the self-stress state of the structure in order to satisfy a serviceability objective and additional robustness objectives. Control commands are defined as sequences of contractions and elongations of active struts to modify the self-stress state of the structure. A two step multiobjective optimization method involving Pareto filtering with hierarchical selection is implemented to determine control commands. Experimental testing on a full-scale active tensegrity structure demonstrates validity of the method. In most cases, control commands are more robust when identified by a multiobjective optimization method as compared to a single objective one. This robustness leads to better control over successive loading events. Evaluation of multiple objectives provides a more global under- standing of tensegrity structure behavior than any single objective. Finally, results reveal opportunities for self-adaptive structures that evolve in unknown environments.