Command-Filtered Backstepping Redesign for Aerial Manipulators Under Aerodynamic and Operational Disturbances

Abstract

The complexity of autonomous Aerial Manipulators (AMs), i.e. Unmanned Aerial Vehicle (UAV) + Robot Manipulator (RM), is growing faster as per our demand of being able to perform complex tasks. This complexity makes the control system to have to take into account somehow the RM dynamics, otherwise the overall behaviour of the system could be compromised. In this work, we thoroughly analyse the overall performance of the AM with a widespread controller designed neglecting the RM dynamics. In particular, the performances under the induced forces/torques provided by a compound interaction of movements of the RM (vibrations) and aerodynamical effects. For the case of study, we consider an UAV multicopter and a generic redundant RM. A complete analysis with realistic simulations on a benchmark is reported.

High-Level Modular Autopilot Solution for Fast Prototyping of Unmanned Aerial Systems

“…This type of controllers -together with the cascade PIDs-are the most commonly used in this kind of multi-rotor platform. Although standard in aerial robotics, the one implemented here is an adapted version of [48] -and references therein-, being briefly summarised next. Thus, let U =col(U 1 ,U 2 ,U 3 ) ∈ R 3 be the virtual command in the Cartesian position outer loop of the cascade, hence becoming the feedback-linearisation controller…”

“…where m ∈ R is the UAV mass, g ∈ R 3 the gravity acceleration vector, T ∈ R the total thrust and ψ ∈ R the yaw angle. On the other hand, the attitude controller of the inner loop is formulated using the command-filtered backstepping technique (see references therein [48]), yielding…”