Dynamic stability of the flying cantilevered pipe conveying and emitting water

Abstract

A cantilevered pipe conveying fluid causes unsuitable motion as flow speed increases, such as fluttering and divergence because of fluid structure interactions. On the other hand, although continuum flying robots actuated by expelling fluid jets are developed by several researchers, they have not taken the interactions into account to design the controller. This study proposes controller for the cantilevered pipe to fly stably, whose tip emits water jets to gain controllable net force, by taking the fluid structure interactions into account. First, the pipe model with nozzles on the head is designed based on some assumptions. Then, the proportional derivative controller to the head position is proposed to dissipate an energy function regardless of the flow speed. If there is no gravity, the controller ensures Lyapunov stability of the system regardless of the flow speed. Finally, the simulation with the proposed controller verifies that the pipe can keep stable even when the flow speed increases. In addition, the stability analysis with various control parameters shows that the stability of the system can be improved by tuning the control parameters.