Noninvasive liquid level sensing technique using laser generated ultrasound (Conference Presentation)

Shape morphing is one of the most appealing applications of adaptive structures. Among the various means of achieving shape morphing, origami-inspired folding is particularly advantageous, because folding is a powerful approach to induce three-dimensional and sophisticated shape changes. However, attaining large-amplitude folding is still a challenge in origami engineering. While promising, the use of active materials as a folding activation strategy is limited due to the constant voltage supply that is required to maintain the desired configuration of the structure. One possible solution is to embed bi-stability into the structure. Bi-stability can play two significant roles here: first, it can significantly reduce the actuation requirement to induce shape morphing, and second, it can maintain the shape change without demanding sustained energy supply. In a previous study by the authors, a unique shape morphing (or self-folding) method using harmonic excitation has been proposed for a bi-stable water-bomb base. However, this approach has some drawbacks because the nonlinear dynamic behaviors of origami are quite sensitive to different design parameters, such as initial conditions, excitation parameters, and inaccuracies in manufacturing. In this study, via numerical simulations, we show that by harnessing the intra-well resonance of the water-bomb structure and incorporating a relatively simple feedback control strategy, one can achieve a rapid and robust morphing using relatively low actuation magnitude. The results of this study can lay the foundation of a new category of morphing origami mechanisms with efficient and reliable embedded actuation.