Nonlinear observer-based impedance control of a fully-actuated hexarotor for accurate aerial physical interaction

Abstract

Purpose

Fully-actuated unmanned aerial vehicles (UAVs) are a growing and promising field of research, which shows advantages for aerial physical interaction. The purpose of this paper is to construct a force sensor-denied control method for a fully-actuated hexarotor to conduct aerial interaction with accurate force exerted outward.

Design/methodology/approach

First, by extending single-dimension impedance model to the fully-actuated UAV model, an impedance controller is designed for compliant UAV pose/force control. Then, to estimate the interaction force between UAV end-effector and external environment accurately, combined with super-twisting theory, a nonlinear force observer is constructed. Finally, based on impedance controller and estimated force from observer, an interaction force regulation method is proposed.

Findings

The presented nonlinear observer-based impedance control approach is validated in both simulation and environments, in which the authors try to use a fully-actuated hexarotor to accomplish the task of aerial physical interaction finding that a specified force is able to be exerted to environment without any information from force sensors.

Originality/value

A solution of aerial physical interaction for UAV system enabling accurate force exerted outward without any force sensors is proposed in this paper.

Citation

Wang, C., Jiao, R. and Zhang, J. (2024), "Nonlinear observer-based impedance control of a fully-actuated hexarotor for accurate aerial physical interaction", Industrial Robot, Vol. 51 No. 4, pp. 683-695. https://doi.org/10.1108/IR-11-2023-0268