Effects of pipe vibration on roll angle of a quadrotor system with a vertical cantilever pipe conveying fluid

A quadrotor + liquid conveying pipe system is used to transport liquids in applications where direct human intervention is impractical, such as firefighting, precision agriculture, industrial maintenance and cleaning. While the quadrotor provides mobility, the pipe acts as a conduit for continuous liquid transport from a reservoir. In this study, the coupled dynamics between quadrotor system and a vertical cantilever pipe conveying fluid were investigated. For this purpose, a coupled model was developed by connecting the pipe and the quadrotor model. It was assumed that the pipe vibrations affect the quadrotor but not the other way around. The effects of fluid speed and distribution impacts based uncontrolled pipe vibrations on the uncontrolled and PD controlled quadrotor were determined. The results show that fluid speed and pipe excitation significantly affect the stability of the quadrotor and cause variations in the roll angle and displacement at the free end of the pipe. It is observed that the pipe vibration and the torque applied to the quadrotor decrease as the fluid speed is increased until the critical speed is reached. It is observed that the flow velocity and the type of disturbance excitation affect the time domain performance criteria of the roll angle.