Guillermo Heredia

University of Seville | US · Robotics, Vision and Control Group

The paper introduces a novel framework for safe and autonomous aerial physical interaction in industrial settings. It comprises two main components: a neural network-based target detection system enhanced with edge computing for reduced onboard computational load, and a control barrier function (CBF)-based controller for safe and precise maneuverin...

This paper introduces a novel compliant mechanism combining lightweight and energy dissipation for aerial physical interaction. Weighting 400~g at take-off, the mechanism is actuated in the forward body direction, enabling precise position control for force interaction and various other aerial manipulation tasks. The robotic arm, structured as a cl...

Fully actuated aerial robot proved their superiority for Aerial Physical Interaction (APhI) over the past years. This work proposes a minimal setup for aerial telemanipulation, enhancing accessibility of these technologies. The design and the control of a 6-DoF joystick with 4-DoF haptic feedback is detailed. It is the first haptic device with stan...

Coaxial multirotors, characterized by overlapping rotors, represent a common solution to increasing payload capacity while maintaining a compact platform size. However, the overlap between motors generates airflow disturbances that, if not taken into account properly, may decrease the system’s overall performance. In this paper, aerodynamic interac...

This paper investigates the ground proximity effects of a fully-actuated multirotor unmanned aerial vehicle (UAV). Different configurations of tilted rotors and a wide range of UAV heights relative to the ground are considered. In order to characterize the effect, an extensive experimental study was conducted on a static test-bench. The experimenta...

In recent years, the fields of application of aerial manipulators have expanded, ranging from infrastructure inspection to physical interaction with flexible elements, such as branches and trees. This article presents the controlled shaking of a tree with an aerial manipulator. Our work aims at contributing to applications like the identification o...

The present work is aimed at analyzing and modelling the aerodynamic interactions of two small-scale tilted propellers operating at low Reynolds numbers near the ground. Two configurations of counter-rotating propellers found in fully-actuated multirotors are investigated: Face-to-Face, where the propeller flows are opposite and non-overlapping, an...

This book contains a selection of papers accepted for presentation and discussion at ROBOT 2022—Fifth Iberian Robotics Conference, held in Zaragoza, Spain, on November 23-25, 2022. ROBOT 2022 is part of a series of conferences that are a joint organization of SEIDROB—Sociedad Española para la Investigación y Desarrollo en Robótica/Spanish Society f...

This book contains a selection of papers accepted for presentation and discussion at ROBOT 2022—Fifth Iberian Robotics Conference, held in Zaragoza, Spain, on November 23-25, 2022. ROBOT 2022 is part of a series of conferences that are a joint organization of SEIDROB—Sociedad Española para la Investigación y Desarrollo en Robótica/Spanish Society f...

Control and stabilization of aerial manipulators is a challenging problem due to the effects of the relative movements of the arm and aerial platform on the dynamics. In many cases, conventional multirotor controllers and autopilots are based on the cascaded structure of underactuated mechanical systems, and consider these effects as perturbations....

In the last years, aerial manipulators, UAVs (Unmanned Aerial Vehicles) with robotic manipulators, have been used for several applications such as inspection tasks, systems monitoring or transportation of loads. In order to supervise the missions, a GCS (Ground Control Station) is used. However, the GCS of the commercial autopilots are just designe...

The use of multirotors has grown significantly in recent years. Understanding their operation and control is essential to continue developing the field of multirotors. Because of this, it is essential to introduce multirotor control in engineering classes in a simple and effective way. However, most multirotor simulators are designed for high-level...

This work proposes a novel proportional-derivative (PD)-type state-dependent Riccati equation (SDRE) approach with iterative learning control (ILC) augmentation. On the one hand, the PD-type control gains could adopt many useful available criteria and tools of conventional PD controllers. On the other hand, the SDRE adds nonlinear and optimality ch...

The inspection and maintenance of power lines with aerial robots requires to decrease as much as possible the performance time given the limited capacity of the batteries and the vast extension of this kind of infrastructure. In order to avoid the waste of time associated to the take-off and landing maneuvers, this paper proposes the use of aerial...

In recent years, aerial manipulators with fully-actuated capabilities are gaining popularity for being used in aerial manipulation operations such as critical infrastructure inspection or aerial manipulation tasks. Those scenarios usually demand the aerial platform to operate in constrained and narrow scenarios. It is well known that in these situa...

En este artículo se describen los primeros robots manipuladores aéreos dotados con brazos robóticos de seis grados de libertad y capacidades de percepción y planificación que se han desarrollado en el mundo. Estos robots son el resultado del proyecto ARCAS (Aerial Robotics Cooperative Assembly System) coordinado por el primero de los autores y fina...

This paper investigates the inspection-of-pipe topic in a new framework, by rotation around a pipe, peculiar to industrial sites and refineries. The evolution of the ultimate system requires prototype design and preliminary tests. A new benchmark has been designed and built to mimic the rotation around a pipe, with the main purpose of assessing the...

Inspection and maintenance tasks are increasingly being carried out by multi-rotor platforms in order to avoid certain risks being taken by humans. In this way, it is necessary to have a good knowledge of the aerodynamic effects that occur when tasks are performed in confined environments. In addition, the use of tilted rotors is becoming more and...

This paper presents a localization system for Unmanned Aerial Vehicles (UAVs) especially designed to be used in infrastructure inspection, where the UAVs have to fly in challenging conditions, such as relatively high altitude (e.g., 15 m), eventually with poor or absent GNSS (Global Navigation Satellite System) signal reception, or the need for a B...

Extreme weather conditions, climate change, damages to the infrastructure (caused by natural and man-made hazards) and traffic impediments negatively impact the reliability of mobility solutions. Risk analysis, adaptation measures and strategies that enable minimizing the impact of both natural and man-made extreme events on seamless transport oper...

This paper presents an aerial manipulation robot consisting of a hexa-rotor equipped with a 2-DOF (degree of freedom) Cartesian base (XY–axes) that supports a 1-DOF compliant joint arm that integrates a gripper and an elastic linear force sensor. The proposed kinematic configuration improves the positioning accuracy of the end effector with respect...

This paper considers the problem of performing bimanual aerial manipulation tasks in grabbing conditions, with one of the arms grabbed to a fixed point (grabbing arm) while the other conducts the task (operation arm). The goal was to evaluate the positioning accuracy of the aerial platform and the end effector when the grabbing arm is used as posit...

In this paper, we propose a new concept of robot which is hybrid, including aerial and crawling subsystems and an arm, and also modular with interchangeable crawling subsystems for different pipe configurations, since it has been designed to cover most industrial oil & gas end-users' requirements. The robot has the same ability than aerial robots t...

This paper presents a novel method for motion planning of aerial long-reach manipulators that considers the aerodynamic effects generated by close surfaces in the trajectory generation process. The aerial manipulation system consists of a multirotor equipped with a robotic long-reach arm that enables multidirectional inspection and also increases c...

This paper considers the inspection by contact of long arrays of pipe structures in hard-to-reach places, typical of chemical plants or oil and gas industries, presenting the design of a hybrid rolling-aerial platform capable of landing and moving along the pipes without wasting energy in the propellers during the inspection. The presented robot ov...

This paper presents the design, modeling and control of a fully actuated aerial robot for infrastructure contact inspection as well as its localization system. Health assessment of transport infrastructure involves measurements with sensors in contact with the bridge and tunnel surfaces and the installation of monitoring sensing devices at specific...

This paper presents the design and development of a winged aerial robot with bimanual manipulation capabilities, motivated by the current limitations of aerial manipulators based on multirotor platforms in terms of safety and range/endurance. Since the combination of gliding and flapping wings is more energy efficient in forward flight, we propose...

On‐site inspection of large‐scale infrastructure often involves high risks for the operators and high insurance costs. Despite several safety measures already in place to avoid accidents, an increasing concern has brought the need to remotely monitor hard‐to‐reach locations, for which the use of aerial robots able to interact with the environment h...

The ability of aerial manipulation robots to reach and operate in high altitude workspaces may result of interest in a wide variety of applications and scenarios that nowadays cannot be accessed easily by human operators. Consider for example the installation of sensors in polluted areas, the insulation of leaks in pipe structures, or the corrosion...

This letter is devoted to benchmarks for aerial manipulation robots (drones equipped with robotic arms), which are demonstrating their potential to conduct tasks involving physical interactions with objects or the environment in high altitude workspaces, being a cost effective solution for example in inspection and maintenance operations. Thus, the...

This paper aims to model the aerodynamic effects in the flight of aerial robots close to obstacles in the oil and gas industries. These models are presented in the form of an aerodynamic effects map which represents the changes in the thrust when an aerial vehicle flies very close to different obstacles. Although there are works related to the fly...

This paper presents a UAV (Unmanned Aerial Vehicle) with intrinsic safety which can interact with people and obstacles while flying in an indoor environment in an autonomous way. A system description including mechanical features, the design of the external protective case, electrical connections and the communication using the Robot Operating Syst...

This paper describes a positioning system for aerial robots consisting of a linear array of time-of-flight (ToF) sensors whose orientation angle is controlled with micro servo, allowing the detection and accurate localization of the contour of a pipe to be inspected. The system, integrated in a hexarotor vehicle, has three operation modes: searchin...

This work is motivated by the need to improve existing systems of interception of drones by using other drones. Physical neutralization of malicious drones is recently reaching interest in the field of counter-drone technologies. The exposure time of these threats is a key factor in environments of high population densities such as cities, where th...

This paper presents the design, modelling and control of a multirotor for inspection of bridges with full contact. The paper analyzes the aerodynamic ceiling effect when the aerial robot approaches the bridge surface from below, including its aerodynamic characterization using Computational Fluid Dynamics (CFD). The proposed multirotor design takes...

This chapter presents the dynamic model of multirotors with multiple arms, which will be used for controller development in Part III and planning in Part V. It first presents the modeling of multirotors and arms individually, and them the coupled kinematic and dynamic model of the aerial robot with multiple arms. The chapter also presents the metho...

This chapter presents the aerodynamic effects that appear when multirotors fly close to different structures, which is a common situation in aerial manipulation. The classical theory used to solve this problem in helicopters is explained, and a generalization of this method to quadrotors is introduced. The chapter also presents validation experimen...

Multirotors with manipulator arms are multibody systems whose mass characteristics (position of center of mass and moments of inertia) change with time when the arms move and bear reaction torques generated by the arm servos. This chapter presents a control system for aerial manipulators based on integral backstepping that estimates all these effec...

The chapter presents the design and modelling of compliant dual arms for aerial manipulation. Physical compliance in the arm joints contributes to increase safety, reliability and robustness of the system during its operation on flight, especially during interaction tasks. The chapter also presents validation experiments of the arms mounted on mult...

A wide range of applications for which Unmanned Aerial Vehicles (UAVs) are ideally suited rely on the development of manipulators capable of exchanging forces with the environment. One such application is the installation and retrieval of intelligent sensors for monitoring wide-spread areas and locations that are difficult to access by any other me...

This paper presents a robotic system using Unmanned Aerial Vehicles (UAVs) for bridge-inspection tasks that require physical contact between the aerial platform and the bridge surfaces, such as beam-deflection analysis or measuring crack depth with an ultrasonic sensor. The proposed system takes advantage of the aerodynamic ceiling effect that aris...

Ground effect on rotary aircraft has been studied for many decades. Although a large body of research results is now available for conventional helicopters, this topic is just beginning to receive attention in the unmanned aerial vehicles community, particularly for small size UAVs. The objective of this papers is to assess the applicability on sma...

The proximity between the multirotor blades and the environmental obstacles restricts the application of aerial manipulators in inspection tasks due to the risk of impacts, the limitation in the reach of the arm, and the physical interactions. This paper presents a long reach aerial manipulator consisting of a hexarotor platform equipped with a 2-D...

This paper summarizes new aerial robotic manipulation technologies and methods, required for outdoor industrial inspection and maintenance, developed in the AEROARMS project. It presents aerial robotic manipulators with dual arms and multi-directional thrusters. It deals with the control systems, including the control of the interaction forces and...

Dual arm aerial manipulation requires the design and development of high performance robotic arms in terms of safety, robustness, and force/torque/impedance control, taking into account the integration in the aerial platform, the strong weight constraints, and the technological limitations of the servo actuators. A compliant joint arm also improves...

This paper presents an anthropomorphic, compliant and lightweight dual arm manipulator designed and developed for aerial manipulation applications with multi-rotor platforms. Each arm provides four degrees of freedom (DOF) in a human-like kinematic configuration for end effector positioning: shoulder pitch, roll and yaw, and elbow pitch. The dual a...

This paper considers the problem of fault detection and identification (FDI) in applications carried out by a group of unmanned aerial vehicles (UAVs) with visual cameras. In many cases, the UAVs have cameras mounted onboard for other applications, and these cameras can be used as bearing-only sensors to estimate the relative orientation of another...

This paper presents the development and experimental validation of a low weight and inertia, human-size and highly dexterous dual arm system designed for aerial manipulation with multirotor platform. The arms, weighting 1.8 kg in total and with a maximum lift load per arm around 0.75 kg, provide five degrees of freedom (DOF) for end-effector positi...

This paper proposes the application of a stereo vision system for estimating and controlling the Cartesian and joint deflection in an anthropomorphic, compliant and ultra-lightweight dual arm designed for aerial manipulation. Each arm provides four degrees of freedom (DOF) for end-effector positioning in a human-like kinematic configuration. A simp...

This paper analyzes the ground effect in multirotors, that is, the change in the thrust generated by the rotors when flying close to the ground due to the interaction of the rotor airflow with the ground surface. This effect is well known in single-rotor helicopters but has been assumed erroneously to be similar for multirotors in many cases in the...

Abstract: The inspection of bridges and other infrastructure with UAVs when the sensors need to be in contact with the surface (i.e. ultrasound for crack inspection or reflector prism for beam deflection) is a great challenge due to the coupling which occurs between the aerial and the inspection problems. This paper presents a new design of a multi...

This paper addresses the problem of collision avoidance in scenarios with multiple aerial vehicles and proposes a method based on a Legendre pseudospectral collocation in order to compute the solution trajectories and guarantee that the safety distance between them is always maintained. The method uses a rolling horizon policy in which trajectories...

This paper presents a reactive method for collision avoidance with multiple aerial vehicles that has been applied in real time considering industrial environments. The proposed method is based on the 3D-Optimal Reciprocal Collision Avoidance algorithm. The main contribution of the proposed method is that it takes into consideration 3D modeled stati...

Increasing flight endurance of Unmanned Aerial Vehicles (UAVs) is a main issue for many applications of these aircrafts. This paper deals with air to air refueling between UAVs. Relative estimation using only INS/GPS system is not sufficiently accurate to accomplish an autonomous dock for aerial refueling using a boom system in the tanker. In this...

This paper presents a efficent conflict detection and resolution (CDR) method for an aerial vehicle sharing airspace with other aerial vehicles. It is based on a conflict detection (CD) algorithm (axis-aligned minimum bounding box) and conflict resoluction (CR) algorithm (genetic algorithms) to find safe trajectories. Monte-Carlo estimation is used...

In this paper, a single DOF anthropomorphic finger module specifically designed for aerial manipulation and grasping is presented, where low weight and compliance are required features for safer performance of the aerial platform. The under-actuated mechanism consists of a high torque micro motor with a small reel for driving a tendon that moves th...

This chapter focuses on the optimal trajectory generation for multiple autonomous vehicles. Nowadays, there are many outdoor and indoor applications where teams of robots and unmanned vehicles are very useful. In these cases the ability of autonomous navigation and adaptive motion control is given by trajectory planning methods. Furthermore, trajec...

This paper presents techniques for GPS based autonomous navigation of heavy vehicles at high speed. The control system has two main functions: vehicle position estimation and generation of the steering commands for the vehicle to follow a given path autonomously. Position estimation is based on fusion of measurements from a carrier-phase differenti...

This article deals with aerial manipulators consisting of unmanned helicopters equipped with robotic multi-link arms. This setup has strong potentialities for structure assembly and manipulation tasks, which makes it a valuable resource in outdoor industrial environments. The article presents an elaborate model of the entire system as well as metho...

Increasing flight endurance of Unmanned Aerial Vehicles (UAVs) is a main issue for many applications of these aircrafts. This paper deals with air to air refueling between UAVs. Relative estimation using only INS/GPS system is not sufficiently accurate to accomplish an autonomous dock for aerial refueling. In this paper we propose a relative state...

This paper presents a system for collision-free trajectory planning with multiple Unmanned Aerial Vehicles (UAVs) which automatically identifies conflicts among them. After detecting conflicts between UAVs, the system resolves them cooperatively using a collision-free trajectory planning algorithm based on a stochastic optimization technique named...