Design and Development of a Novel Controller for Robust Attitude Stabilisation of an Unmanned Air Vehicle for Nuclear Environments

Abstract

This study presents two new robust nonlinear control algorithms based on the theory of time-varying sliding mode control (TVSMC) strategy to stabilize the attitude of an unmanned aerial vehicle (UAV) for nuclear decommissioning applications. Constant radiation affects the UAV performance. For instance, its parameters are time-varying and subject to uncertainty all the time. This is especially important in designing sliding mode control as the motion of the control system in the reaching phase is highly sensitive against environmental disturbances and parameter uncertainties. In this study, two types of time-varying sliding manifolds are proposed to eliminate the reaching phase and to enhance the robust performance in the aforementioned phase. Therefore, two novel types of time-varying sliding surfaces are introduced based on the initial condition as intercept-varying sliding mode control (IVSMC) approaches. In the first proposed method, the reaching time from initial manifold to the desired one is similar to that of the conventional SMC method. While in the second proposed IVSMC scheme, one can accelerate or decelerate the motion of the time-varying sliding manifolds at any selected time. Furthermore, chattering phenomenon can be avoided using two techniques known as boundary layer and continuous SMC. Finally, to highlight the robust performance of the proposed methods, a quadrotor UAV subject to external disturbances is simulated.

Real-time Nonlinear Parameter Estimation and Tracking Control of Unmanned Aerial Vehicles in Closed-Loop

“…Chattering is a common issue in designing SMC for the autonomous system. Several studies have been investigated to reduce the chattering as well as to compensate the effect of unmodelled dynamics as presented in [10][11][12] .…”

A fast L1 adaptive constrained back-stepping controller using barrier Lyapunov function for anuncertain submersible vehicle

“…The use of robotics and autonomous systems in hazardous environments, which are not easily accessible to human have been the subject of study in various fields 1,2,3 . One of the hazardous environments that human being has not been able to discover effectively is the deep see and ocean surfaces.…”

An Adaptive Scheme to Estimate Unknown Parameters of an Unmanned Aerial Vehicle

“…Robotics and autonomous systems have recently drawn the attention of academics and industries in various fields to assist human in challenging environments such as off-shore and underwater applications, space exploration, mining and volcanic fields, and nuclear decommissioning. For example, in [9,13] the use of robotic manipulator and quadcopter for the nuclear decommissioning application was investigated. Improving autonomy and cognition of robotic systems can unlock their potential for hazard monitoring.…”

“…To address the chattering problem in sliding mode control techniques, significant effort has been made in the literature. In the context of UAV application, the interested reader is referred to [12,13].…”