REDUCTION OF THE PERIODIC THERMOELASTIC DEFORMATION IN TRUSS-STRUCTURES BY DESIGN REFINEMENTS AND ACTIVE LOADS

The study presented in this paper addresses the problem of reducing th e periodic thermoelastic deformation in typical space truss-structures . Emphasis is placed on the exploration of the effectiveness of two di fferent ways of coping with the undesired deformation. In the first wa y, different types of designs were examined. The designs were selected in such a way that the various structures differ only by the layout o f the basic cells from which they are constructed and, therefore, thes e variations do not change the original functioning qualities of the s tructure. Different material types were also examined. In the second a pproach, the effectiveness of applying external periodic loads at some a priori defined locations over the structure was examined. Various o bjective functions were tested, including local and global considerati ons. The results show the favored combination of design modes and mate rials and demonstrate the ability of external control loads to reduce the deformation level over the entire structure or at some selected lo cations.