Citation: González-García, J.;
Gómez-Espinosa, A.;
García-Valdovinos, L.G.;
Salgado-Jiménez, T.; Cuan-Urquizo,
E.; Cabello, J.A.E. Model-Free
High-Order Sliding Mode Controller
for Station-Keeping of an
Autonomous Underwater Vehicle in
Manipulation Task: Simulations and
Experimental Validation. Sensors
2022, 22, 4347. https://doi.org/
10.3390/s22124347
Academic Editors: Jacopo Aguzzi,
Giacomo Picardi,
Damianos Chatzievangelou,
Simone Marini, Sascha Flögel,
Sergio Stefanni, Peter Weiss and
Daniel Mihai Toma
Received: 7 May 2022
Accepted: 30 May 2022
Published: 8 June 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
Article
Model-Free High-Order Sliding Mode Controller for
Station-Keeping of an Autonomous Underwater Vehicle in
Manipulation Task: Simulations and Experimental Validation
Josué González-García
1
, Alfonso Gómez-Espinosa
1,
* , Luis Govinda García-Valdovinos
2,
* ,
Tomás Salgado-Jiménez
2
, Enrique Cuan-Urquizo
1
and Jesús Arturo Escobedo Cabello
1
1
Tecnologico de Monterrey, Escuela de Ingenieria y Ciencias, Av. Epigmenio González 500, Fracc. San Pablo,
Queretaro 76130, Mexico; a01208772@tec.mx (J.G.-G.); ecuanurqui@tec.mx (E.C.-U.);
arturo.escobedo@tec.mx (J.A.E.C.)
2
Center for Engineering and Industrial Development (CIDESI), Energy Division, Queretaro 76125, Mexico;
tsalgado@cidesi.edu.mx
* Correspondence: agomeze@tec.mx (A.G.-E.); ggarcia@cidesi.edu.mx (L.G.G.-V.);
Tel.: +52-442-238-3302 (A.G.-E.)
Abstract:
The use of autonomous underwater vehicles (AUVs) has expanded in recent years to
include inspection, maintenance, and repair missions. For these tasks, the vehicle must maintain
its position while inspections or manipulations are performed. Some station-keeping controllers for
AUVs can be found in the literature that exhibits robust performance against external disturbances.
However, they are either model-based or require an observer to deal with the disturbances. Moreover,
most of them have been evaluated only by numerical simulations. In this paper, the feasibility
of a model-free high-order sliding mode controller for the station-keeping problem is validated.
The proposed controller was evaluated through numerical simulations and experiments in a semi-
Olympic swimming pool, introducing external disturbances that remained unknown to the controller.
Results have shown robust performance in terms of the root mean square error (RMSE) of the vehicle
position. The simulation resulted in the outstanding station-keeping of the BlueROV2 vehicle, as the
tracking errors were kept to zero throughout the simulation, even in the presence of strong ocean
currents. The experimental results demonstrated the robustness of the controller, which was able to
maintain the RMSE in the range of 1–4 cm for the depth of the vehicle, outperforming related work,
even when the disturbance was large enough to produce thruster saturation.
Keywords: AUV; station-keeping; SMC; finite-time
1. Introduction
Autonomous underwater vehicles (AUVs) have been widely used in recent years as
an alternative to extremely costly, time-consuming, and risky human underwater oper-
ations [
1
]. Most of the tasks performed by these vehicles are for data-gathering applica-
tions [
2
]. However, there is an increasing interest for their use in inspection, maintenance,
and repair operations [
3
] that require manipulation and interaction with objects in the
underwater environment. Nowadays, this is mainly performed by remotely operated
vehicles (ROVs) equipped with sensors, actuators, or manipulators designed for these
specific tasks. Human intervention to remotely control the manipulator enables these
missions by allowing them to respond to changes caused by the unpredictable underwater
environment. Nevertheless, recent research has addressed the full automation of such
tasks [4–7], including the implementation of collaborative AUVs [8–12].
Regardless of whether the manipulation task is performed by humans or autonomously,
fulfilling some operations, such as precise navigation and station-keeping, is a challenge
for researchers. These operations are quite difficult to achieve due to unknown external
Sensors 2022, 22, 4347. https://doi.org/10.3390/s22124347 https://www.mdpi.com/journal/sensors
