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In this study, the results of experimental and analytical study on shape control of a composite beam with embedded shape memory alloy wire actuators are presented. The effects of the reactive moment of the SMA wire actuators on the shape control test are observed in detail. In shape control of a flexible composite structure, the reactive moment by SMA wire actuators can alter the deformed shape of composite beams which are subjected to external and thermal loads. The results obtained from the shape control test confirm that the deflected shape of a composite beam with embedded SMA wire actuators can be controlled by electrical resistance heating. An analytical model describing the snapthrough of composite beams is also presented.

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In this paper, the thermal buckling and postbuckling behaviours of a composite beam with embedded shape memory alloy (SMA) wires are investigated experimentally and analytically. For the purpose of enhancing the critical buckling temperature and reduction of the lateral deflection on thermal buckling and postbuckling, the characteristics of thermal buckling are investigated through the use of the shape recovery force. The results of thermal buckling tests using uniformly heated and clamped composite beam specimens with embedded SMA wire actuators are discussed. The temperature-load-deflection behaviour records present quantitatively how the shape recovery force affects the thermal buckling behaviour. For this experiment, we considered the initial geometric imperfections, the slenderness ratio of the beam and the embedding position of the SMA wire actuators. The experimental results show that the shape recovery force reduces the thermal expansion of the composite laminated beam. This results in an increase of the critical buckling temperature and a reduction of the lateral deflection of the beams.

In this paper, an experimental study on the buckling and postbuckling control of a laminated composite beam with eccentrically embedded NiTi actuators is performed. For the purpose of enhancing the critical buckling load, buckling control is investigated through the use of reactive moment associated with the shape recovery force of NiTi actuators. To improve the control authority for the buckling and postbuckling control of the NiTi-composite beam, closed-loop control is used. The buckling and postbuckling control behaviours are presented and discussed qualitatively and quantitatively on load-deflection plots considering stacking sequence of the laminate, slenderness ratio of the beam and activation conditions of the NiTi actuators. The experimental results show that the buckling control can be extended to the postbuckling of the NiTi-composite beam with the proper reactive moment.