Design of a multi-vectored thrust aerostat with a reconfigurable control system

Abstract

This paper presents an aerostat developed in the shape of an ellipsoid, which is a cross between a ball and a water droplet. This aerostat is equipped with four vectored thrusters. Its coefficient of forward drag is smaller than that of the spherical aerostat, and its lift efficiency is higher than that of the conventional airship. To allocate control among the multi-vectored thrusters, a control system based on pseudo-inverse dynamics is designed. A reconfiguration strategy is also proposed to reallocate actuators in case of control actuator failure. Three diagonal weight matrices are combined to represent all possible failure situations occurred on vectored thruster, they make the reconfigurable controller more general. Based on simulation results under different fault situations, the reconfigurable control system performs more effectively than a normal control system in cases of actuator failure, even when more than one actuator fails. Reconfigurable ability of controller also validated in real flight experiment.

Nonlinear MPC for a Sensorless Multi‐Vectored Propeller Airship Based on Sliding Mode Observer with Saturation

“…The combined force of the buoyancy and the gravity are presented in Equation (3). Where , and are the pitch, yaw, and roll angles, respectively.…”

“…Affected by unpredictable harsh weather, heat flow, and wind field during flying, the internal parameters of the airship may change, and the control performance deteriorate , so that some failure may occur. Therefore, the primary goal is to design a fault tolerant control to maintain stability and controllability under harsh environments . Meanwhile, strong robustness is required.…”

Three-Dimensional Path-Following Control of a Robotic Airship with Reinforcement Learning

“…The lift of an airship mainly comes from the buoyancy of the gas, and therefore, it does not have to do continuous movement to balance gravity, which makes it a promising platform for long-endurance and low-energy consumption. In the last two decades, airships such as heavy-duty airships and stratospheric airships [1] have gained increasing interest given their potential in communication relay, space observation, and military reconnaissance. Control strategy has always been an important subject in airship research.…”

Degraded Planary Tracking Control of an Omnidirectional Vectored-Thruster Aerostat

“…The ellipsoidal shape displays a reduced lateral profile in crosswinds and has a higher lift efficiency. Therefore, this shape is advantageous for a platform hovering at a given altitude (Chen et al (2016)). The efficiency of a conventional actuator, such as an aerodynamic control surface for stratospheric platforms is decreased by the low-atmospheric density and flight speed (Yang and Yan (2018); Azinheira et al (2015); Yang and Yan (2016); Yang (2018)).…”