We developed a motor driven wrist brace that can adjust its stiffness by changing its mesoscale geometry. The design involves a plate structure that folds from a flexible flat shape to a stiff corrugated shape by means of a motor driven tendon. The structure is built using a laminate of rigid and flexible layers, with embedded flexural hinges that allow it to fold. The paper proposes a simplified analytical model to predict stiffness, and physical three-point bending tests indicate that the brace can increase its stiffness up to fifty times by folding.

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