“Structure-borne travelling waves (SBTW) have been observed throughout nature in the locomotive behaviour of creatures on land with snakes and snails, and in water in the swimming modes of fish and rays. It has been shown that structure-borne travelling waves can be excited in mechanical structures to drive the motion of particles (sand, salt, etc.) and fluid on actuated surfaces of beams and plates. An effective tool for the generation of SBTW in finite structures utilizes the modal properties of the structure itself by using the superposition of standing waves with a phase offset which forms travelling waves without reflections at the boundaries. This method has been used to generate SBTW suitable for wave-driven motion in beams and plates, but the waves up to now these methods have only been driven along a single axis. This work investigates the use of superimposing SBTW that propagates orthogonally. By adjusting the excitation conditions of the constituent SBTW, the overall wavefront can be redirected to propagate in any prescribed direction. These superimposed STBW could be used to drive the motion of particulates in industrial settings for material transport applications. These SBTW can also be used to propel the active structure in two dimensions while suspended in a fluid.
Fusion of Analysis, Simulation, & Testing
innovation through vibration
