André Schneider de Oliveira - Academia.edu (original) (raw)

Papers by André Schneider de Oliveira

IEEE Access, 2020

This paper addresses the control of a fleet of unmanned aerial systems (UAVs), termed as drones, ... more This paper addresses the control of a fleet of unmanned aerial systems (UAVs), termed as drones, for flight formation problems. Getting drones to fly in formation is a relevant problem to be solved when cooperative cargo transportation is desired. A general approach for this problem considers the coordination of a fleet of UAVs, by fusing all information coming from several individual sensors posed on each UAVs. However, this approach induces a high cost as every UAV should have its advanced perception system. As an alternative, this paper proposes the use of a single perception system by a fleet composed of several elementary drones (workers) with primitive low-cost sensors and a leader drone carrying a 3D perception source. We propose a Quadral-Fuzzy approach to ensure that all drones fly in formation and will not collide with each other or with environment obstacles. We also develop a new way to compute potential fields based on possibility fuzzy (fuzziness) measure with the focus of avoiding collisions between the drones. The proposed approach encompasses four high-coupled intelligent controllers that respectively control the leader and worker drones' motion and implement obstacle and collision avoidance procedures. Simulation results using a fleet of four aerial drones are presented, showing the potential for solving usual problems to flights in formation, such as dodging obstacles, avoiding collisions between the drones, among others. INDEX TERMS Unmanned aerial vehicles (UAVs), multi-agent systems, distance-based formation, flight-formation control, autonomous flight.

Studies in Computational Intelligence

The objective of this chapter is to provide a simple tutorial on how to use a virtual reality tag... more The objective of this chapter is to provide a simple tutorial on how to use a virtual reality tag (VR-TAG) tool and a Robot Operating System–compatible simulated multirotor vehicle to achieve the position of a small mobile ground robot, making possible the creation of a cooperative schema among them. The great novelty of the proposed architecture is that the ground robots do not have any onboard odometry, and all the position information is provided by the multirotor using a camera and the VR-TAGs to evaluate it. This kind of architecture poses value for real-world cooperative multiple robot research, in which the cost of constructing a large number of small robots makes practical applications inviable. In such cases, simple robots with minimal control hardware and sensors are a good alternative, and offboard positioning and control of these robots can be effective.

This paper introduces the mobile robot CRAS (Climbing Robot for Autonomous inSpection) for autono... more This paper introduces the mobile robot CRAS (Climbing Robot for Autonomous inSpection) for autonomous NDT inspection of weld beads from industrial super-duplex steel vessels. The surfaces to be inspected are under high temperature (80 \(^\circ \)C–135 \(^\circ \)C) and the inspection is based on ultrasound. CRAS presents magnetic wheels as adhesion method and a perception system able to identify and follow weld beads. This paper approaches some current challenges for such inspection mainly due high temperatures and adopted solutions as well as future steps of CRAS development.

The advancement of technology and techniques applied to robotics contributes to increasing the qu... more The advancement of technology and techniques applied to robotics contributes to increasing the quality of life and safety of humanity. One of the most widespread applications of mobile robotics is related to monitoring indoor environments. However, due to factors such as the size of the environment impacting the monitoring response, battery autonomy, and autonomous navigation in environments with unknown obstacles, they are still significant challenges in the diffusion of mobile robotics in these areas. Strategy adopting multiple robots can overcome these challenges. This work presents an approach to use multi-robots in hazardous environments with gas leakage to perform spatial mapping of the gas concentration. Obstacles arranged in the environment are unknown to robots, then a fuzzy control approach is used to avoid the collision. As a result of this paper, spatial mapping of an indoor environment was carried out with multi-robots that reactively react to unknown obstacles consider...

2017 Latin American Robotics Symposium (LARS) and 2017 Brazilian Symposium on Robotics (SBR), 2017

This work presents a new concept of environment mapping aiming to identify dynamic objects in the... more This work presents a new concept of environment mapping aiming to identify dynamic objects in the scene, and then estimate their direction and future position. The motion analysis is performed directly in the traditional 2D costmap through three different map frames. Costmap is a traditional mapping technique that uses an occupation grid is used, where each cell has a degree of uncertainty about whether it is occupied or not. The future pose of mobile object is estimated through its motion' behavior, analyzing its previous poses. A representation map called RGB-costmap is created by using the three layers of a traditional RGB image, where each layer has a different meaning. The red layer has the estimation of future position of the object and the current position, in the green layer are added the static objects of the map and in the blue layer there is the past positions of the dynamic object.

2018 Latin American Robotic Symposium, 2018 Brazilian Symposium on Robotics (SBR) and 2018 Workshop on Robotics in Education (WRE), 2018

The cooperation between multiple mobile robots is a robust method to reach various objectives or ... more The cooperation between multiple mobile robots is a robust method to reach various objectives or expand system capabilities. A unified approach to control of robot swarm allows the perception sharing, not requiring the use of an expensive system in each agent. Thus, the information acquired by perception system of robot leader can introduce the autonomy capability in a significant number of mobile robots, sharing resources. This work discusses the use of a robot swarm to cleaning tasks with formation maintaining and obstacle avoidance, aiming to perform the job more quickly and efficiently than using only one robot or several in a disorderly way. The approach is based on a leader agent that executes the autonomous navigation through a LIDAR perception system and follower agents which are responsible for maintaining formation concerning its leader. A Fuzzy intelligent behavior commands the dynamic formation adaptation of robot swarm aiming to overcome obstacles.

2019 Latin American Robotics Symposium (LARS), 2019 Brazilian Symposium on Robotics (SBR) and 2019 Workshop on Robotics in Education (WRE), 2019

AIR is a climbing robot designed for nondestructive testing and inspection of weld seams in tanks... more AIR is a climbing robot designed for nondestructive testing and inspection of weld seams in tanks and vessels of the oil and gas industry. In this paper a Fuzzy control system is proposed to a optimal selection of Levels of Autonomy (LoA) at each moment, mixing joystick inputs from an operator and sensor information from the environment to ensure that the movement of tracking weld seams is being achieved while allowing the operator to have full control of the robot's movements without having to control each maneuver manually. Experiments were executed in a simulator environment and are presented along with future ideas for research.

2020 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2020

This work presents multiple small robots in an unhealthy industrial environment responsible for d... more This work presents multiple small robots in an unhealthy industrial environment responsible for detecting harmful gases to humans, avoiding possible harmful effects on the body. Mixed reality is widely used, considering that the environment and gases are virtual and real small robots. Essential components for the experiments are virtual, such as gases and BioCyber-Sensors. The results establish the great potential for applications in several areas, such as industrial, biomedical, and services. The entire system was developed based on ROS (Robot Operating System), thus the ease in diversifying different applications and approaches with multiple agents. The main objective of small robots is to guaranty a healthy work environment.

This paper aims to present an automated experimentation platform designed to work with multiple m... more This paper aims to present an automated experimentation platform designed to work with multiple mobile robots into industrial scenarios using Robot Operating System (ROS). Robot swarm is a system with complexity proportional of group size, expensive and with arduous setup. Virtual environments can be used to expedite the testing, but also are very difficult due to a hard-work to configure each robot. The proposed platform is a tool set to easily configure the experimentation environment, aiming the swarm tasks, with most popular perception systems, absolute or relative localization reference, and position controllers. The user specifies in tool only the amount of robots required, sensor and function, without having to configure each robot individually for the simulation. This paper presents examples to multi-robot setup in industrial scenarios, through a simple parameterization script. The memory consumption is demystified to given to allow the estimation of computational resources ...

2020 IEEE International Conference on Industrial Technology (ICIT), 2020

In this paper is presented the design, construction and evaluation of an autonomous mobile robot,... more In this paper is presented the design, construction and evaluation of an autonomous mobile robot, designed to outdoor competitions. The category of outdoor competition, in Brazil named Trekking Pro, is based on a mobile robot in an open field, which must pass through preset coordinates. A commercial (at first remote controlled) robot was adapted for autonomous operation. The perception of the robot consists of 9-axis Absolute Orientation Sensor and an encoder. At fist, the system was simulated in a ROS (Robotic Operation System) environment integrated with a scene V-REP (Virtual Robot Experimentation Platform). PID controllers, were used in implementation. Afterwards, a prototype was built, that participated in a competition with success, winning the first place. Both simulation and real-world experimental results of the constructed prototype are shown in detail. The robot described in this paper was the champion of the Winter Challenge 2018 (Robocore - Brazil) in the Trekking Pro c...

IEEE Sensors Journal, 2021

This paper discusses a novel collective sensing approach using autonomous sensors specially desig... more This paper discusses a novel collective sensing approach using autonomous sensors specially designed to monitor gas leaks and search for gas sources. The proposed collective behavior aims to improve the gas-source search by sharing information between mobile sensors and reducing the risks associated with gas leakage. The group acts as a composite sensor that can move independently to search for an optimal sensing zone. The autonomous searching behavior is bio-inspired by colonies of bacteria that continuously seek energy sources throughout their existence. Each sensor makes its own autonomous search decision, considering the group sense, to move in the direction of a better energy source. The collective approach is based on autonomous agents sharing information to achieve a collective sense of gas perception and utilizes more intelligent searching. The method is evaluated in a cyber-physical system specially developed to safely experiment with gases and mobile sensors while reproduc...

2020 IEEE 18th International Conference on Industrial Informatics (INDIN), 2020

Modern industry demands techniques that ensure the operability of its processes, and even though ... more Modern industry demands techniques that ensure the operability of its processes, and even though the exponential technological advance in the last two decades in the manufacturing field, failures, waste, and unexpected interruptions are still present in this sector's daily routine. Within the Industry 4.0 context, fault-tolerant (FT) production systems remain a complex issue and sometimes represent a vulnerable aspect. Fault-tolerance techniques dedicated to autonomous and distributed systems, in a cyber-physical system (CPS) perspective, need to be investigated to follow the evolutionary pace of the manufacturing scenarios. This paper overviews these concepts and analyses the current situation in developing FT for CPS systems through a systematic literature review. The paper also discusses the research challenges in this new kind of FT systems due to new distributed architectures and emerging technologies, matching the several fault- tolerance phases.

Abstract. This paper discusses an improvement for an autonomous robot’s magnetic climbing system ... more Abstract. This paper discusses an improvement for an autonomous robot’s magnetic climbing system necessary to perform the inspection of metal plates and weld beads in internal/external LPG storage sphere’s surfaces. This task typically covers up to 360◦ in the roll-pitch-yaw angles navigation with respect to the Earth‘s surface plan. Also, the storage spheres’ metal surfaces present non-modeled disturbances (such as surface irregularities, rust dust, welding seams...) that can change the adhesion force, requiring an active control to maintain the force balance needed for trajectory tracking. Classic approaches utilize distance sensors to detect gaps between the wheel and the surface, providing a low-level feedback to the control system that, generally, does not have an active compensation of adhesion, thus, disturbing the robot navigation. Unfortunately this method is inappropriate due to the adhesion system’s nonlinear behavior (adhesion force between wheel and surface decreases ra...

This chapter aims to present a new ROS package to automate experimentation with multiple mobile r... more This chapter aims to present a new ROS package to automate experimentation with multiple mobile robots. A robot swarm is a specific system that requires a complicated setup and has a high cost with regard to experimentation. Virtual environments can be used to expedite testing; however, these also are very laborious. This package is a tool set to easily configure the experimentation environment for swarm tasks with the most popular perception systems and absolute or relative localization references. The user specifies in the tool only the number of robots required, sensors, and functions without having to configure each robot individually for the simulation. This chapter presents two examples of the developed package to show how the new package simplifies working with swarms of robots and focuses on the application rather than the required configuration. An example of a formation maintained through the fuzzy approach is developed to demonstrate the potential of the proposed package....

Sensors

Realizing autonomous inspection, such as that of power distribution lines, through unmanned aeria... more Realizing autonomous inspection, such as that of power distribution lines, through unmanned aerial vehicle (UAV) systems is a key research domain in robotics. In particular, the use of autonomous and semi-autonomous vehicles to execute the tasks of an inspection process can enhance the efficacy and safety of the operation; however, many technical problems, such as those pertaining to the precise positioning and path following of the vehicles, robust obstacle detection, and intelligent control, must be addressed. In this study, an innovative architecture involving an unmanned aircraft vehicle (UAV) and an unmanned ground vehicle (UGV) was examined for detailed inspections of power lines. In the proposed strategy, each vehicle provides its position information to the other, which ensures a safe inspection process. The results of real-world experiments indicate a satisfactory performance, thereby demonstrating the feasibility of the proposed approach.

Robot 2019: Fourth Iberian Robotics Conference, Nov 20, 2019

Sensors

This work proposes a novel semantic perception system based on computer vision andmachine learnin... more This work proposes a novel semantic perception system based on computer vision andmachine learning techniques. The main goal is to identify objects in the environment and extracttheir characteristics, allowing a dynamic interaction with the environment. The system is composedof a GPU processing source and a 3D vision sensor that provides RGB image and PointCloud data.The perception system is structured in three steps: Lexical Analysis, Syntax Analysis and finallyan Analysis of Anticipation. The Lexical Analysis detects the actual position of the objects (ortokens) in the environment, through the combination of RGB image and PointCloud, surveying theircharacteristics. All information extracted from the tokens will be used to retrieve relevant featuressuch as object velocity, acceleration and direction during the Syntax Analysis step. The anticipationstep predicts future behaviors for these dynamic objects, promoting an interaction with them interms of collisions, pull, and push actio...

Journal of Intelligent & Robotic Systems

This work presents a novel method to quasi-omnidirectional control of an intelligent inspection r... more This work presents a novel method to quasi-omnidirectional control of an intelligent inspection robot designed to work inside and outside spherical storage tanks. The main objective is to promote a stable and smooth navigation during inspection tasks, ensuring the safety motion under adhesion and kinematic constraints. The robot is designed with four independent steerable magnetic wheels and a mechanical topology that allows the correct adjustment of adhesion system. A scheduled Fuzzy control is developed to achieve an optimal behavior and maximize the robot’s maneuverability, considering the magnetic restrictions of adhesion system and kinematic constraints of the inspection robot. The high adaptability of its mechanical topology (i.e., wheel misalignment, magnetic adhesion system, wheel camber and flexibilities in mechanical structure) and gravitational disturbance introduce many nonlinear characteristics in dynamic behavior that cannot be neglected, making the determination of its dynamic model a complex task. The Fuzzy approach allows to project a control system without a depth knowledge of its dynamic properties, to minimize the dynamic disturbances found in robot structure. Thus, the proposed motion control works according to the robot specific characteristics to ensure the quasi-omnidirectional motion over a reliable adhesion to tank surface and to minimize the effects of wheels kinematic constraints.

Journal of Intelligent & Robotic Systems

This paper presents a novel approach to environment mapping prediction with focus on autonomous c... more This paper presents a novel approach to environment mapping prediction with focus on autonomous climbing robot to NDT (Non-Destructive Technique) inspection. In industrial installations, the inspection of non-planar surfaces requires that NDT probes passe on whole surface, while the autonomous robot navigates over an unknown environment based only on its perception abilities. However, the path planning of inspection is not a trivial task specially when there is no precise information about environment. In this work, a special kind of climbing robot is used to inspect large metallic surfaces such as spherical pressure vessels used to store Liquified Petroleum Gas (LPG). The robot has adherence skills that allow it to safely navigate through the internal and external surface of the vessel. As a result, robot mobility suffers from hard magnetic adhesion constraints. A new approach is proposed to environment detailed prediction, including specific characteristic (like weld beads and plates) of inspected surface. The goal is the automatic extraction of some environment characteristics to predict the storage tank dimensions and robot localization, based on a group of 3D perception sources (laser rangefinder, light detection and ranging and depth camera) mounted over a rolling platform to improve its reach. The environment prediction is carried out after the robot visually detects two or more weld beads corners. A multi-measuring environment is firstly build by Fuzzy data fusion of the different perception measurements allowing to estimate plates and weld beads based on design and safety standards. Virtual and real experiments are carried out to illustrate proposed method performance.

Robotica, 2015

SUMMARY Differential kinematics is a traditional approach to linearize the mapping between the wo... more SUMMARY Differential kinematics is a traditional approach to linearize the mapping between the workspace and joint space. However, a Jacobian matrix cannot be inverted directly in redundant systems or in configurations where kinematic singularities occur. This work presents a novel approach to the solution of differential kinematics through the use of dual quaternions. The main advantage of this approach is to reduce “drift” error in differential kinematics and to ignore the kinematic singularities. An analytical dual-quaternionic Jacobian is defined, which allows for the application of this approach in any robotic system.

IEEE Access, 2020

This paper addresses the control of a fleet of unmanned aerial systems (UAVs), termed as drones, ... more This paper addresses the control of a fleet of unmanned aerial systems (UAVs), termed as drones, for flight formation problems. Getting drones to fly in formation is a relevant problem to be solved when cooperative cargo transportation is desired. A general approach for this problem considers the coordination of a fleet of UAVs, by fusing all information coming from several individual sensors posed on each UAVs. However, this approach induces a high cost as every UAV should have its advanced perception system. As an alternative, this paper proposes the use of a single perception system by a fleet composed of several elementary drones (workers) with primitive low-cost sensors and a leader drone carrying a 3D perception source. We propose a Quadral-Fuzzy approach to ensure that all drones fly in formation and will not collide with each other or with environment obstacles. We also develop a new way to compute potential fields based on possibility fuzzy (fuzziness) measure with the focus of avoiding collisions between the drones. The proposed approach encompasses four high-coupled intelligent controllers that respectively control the leader and worker drones' motion and implement obstacle and collision avoidance procedures. Simulation results using a fleet of four aerial drones are presented, showing the potential for solving usual problems to flights in formation, such as dodging obstacles, avoiding collisions between the drones, among others. INDEX TERMS Unmanned aerial vehicles (UAVs), multi-agent systems, distance-based formation, flight-formation control, autonomous flight.

Studies in Computational Intelligence

The objective of this chapter is to provide a simple tutorial on how to use a virtual reality tag... more The objective of this chapter is to provide a simple tutorial on how to use a virtual reality tag (VR-TAG) tool and a Robot Operating System–compatible simulated multirotor vehicle to achieve the position of a small mobile ground robot, making possible the creation of a cooperative schema among them. The great novelty of the proposed architecture is that the ground robots do not have any onboard odometry, and all the position information is provided by the multirotor using a camera and the VR-TAGs to evaluate it. This kind of architecture poses value for real-world cooperative multiple robot research, in which the cost of constructing a large number of small robots makes practical applications inviable. In such cases, simple robots with minimal control hardware and sensors are a good alternative, and offboard positioning and control of these robots can be effective.

This paper introduces the mobile robot CRAS (Climbing Robot for Autonomous inSpection) for autono... more This paper introduces the mobile robot CRAS (Climbing Robot for Autonomous inSpection) for autonomous NDT inspection of weld beads from industrial super-duplex steel vessels. The surfaces to be inspected are under high temperature (80 \(^\circ \)C–135 \(^\circ \)C) and the inspection is based on ultrasound. CRAS presents magnetic wheels as adhesion method and a perception system able to identify and follow weld beads. This paper approaches some current challenges for such inspection mainly due high temperatures and adopted solutions as well as future steps of CRAS development.

The advancement of technology and techniques applied to robotics contributes to increasing the qu... more The advancement of technology and techniques applied to robotics contributes to increasing the quality of life and safety of humanity. One of the most widespread applications of mobile robotics is related to monitoring indoor environments. However, due to factors such as the size of the environment impacting the monitoring response, battery autonomy, and autonomous navigation in environments with unknown obstacles, they are still significant challenges in the diffusion of mobile robotics in these areas. Strategy adopting multiple robots can overcome these challenges. This work presents an approach to use multi-robots in hazardous environments with gas leakage to perform spatial mapping of the gas concentration. Obstacles arranged in the environment are unknown to robots, then a fuzzy control approach is used to avoid the collision. As a result of this paper, spatial mapping of an indoor environment was carried out with multi-robots that reactively react to unknown obstacles consider...

2017 Latin American Robotics Symposium (LARS) and 2017 Brazilian Symposium on Robotics (SBR), 2017

This work presents a new concept of environment mapping aiming to identify dynamic objects in the... more This work presents a new concept of environment mapping aiming to identify dynamic objects in the scene, and then estimate their direction and future position. The motion analysis is performed directly in the traditional 2D costmap through three different map frames. Costmap is a traditional mapping technique that uses an occupation grid is used, where each cell has a degree of uncertainty about whether it is occupied or not. The future pose of mobile object is estimated through its motion' behavior, analyzing its previous poses. A representation map called RGB-costmap is created by using the three layers of a traditional RGB image, where each layer has a different meaning. The red layer has the estimation of future position of the object and the current position, in the green layer are added the static objects of the map and in the blue layer there is the past positions of the dynamic object.

2018 Latin American Robotic Symposium, 2018 Brazilian Symposium on Robotics (SBR) and 2018 Workshop on Robotics in Education (WRE), 2018

The cooperation between multiple mobile robots is a robust method to reach various objectives or ... more The cooperation between multiple mobile robots is a robust method to reach various objectives or expand system capabilities. A unified approach to control of robot swarm allows the perception sharing, not requiring the use of an expensive system in each agent. Thus, the information acquired by perception system of robot leader can introduce the autonomy capability in a significant number of mobile robots, sharing resources. This work discusses the use of a robot swarm to cleaning tasks with formation maintaining and obstacle avoidance, aiming to perform the job more quickly and efficiently than using only one robot or several in a disorderly way. The approach is based on a leader agent that executes the autonomous navigation through a LIDAR perception system and follower agents which are responsible for maintaining formation concerning its leader. A Fuzzy intelligent behavior commands the dynamic formation adaptation of robot swarm aiming to overcome obstacles.

2019 Latin American Robotics Symposium (LARS), 2019 Brazilian Symposium on Robotics (SBR) and 2019 Workshop on Robotics in Education (WRE), 2019

AIR is a climbing robot designed for nondestructive testing and inspection of weld seams in tanks... more AIR is a climbing robot designed for nondestructive testing and inspection of weld seams in tanks and vessels of the oil and gas industry. In this paper a Fuzzy control system is proposed to a optimal selection of Levels of Autonomy (LoA) at each moment, mixing joystick inputs from an operator and sensor information from the environment to ensure that the movement of tracking weld seams is being achieved while allowing the operator to have full control of the robot's movements without having to control each maneuver manually. Experiments were executed in a simulator environment and are presented along with future ideas for research.

2020 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2020

This work presents multiple small robots in an unhealthy industrial environment responsible for d... more This work presents multiple small robots in an unhealthy industrial environment responsible for detecting harmful gases to humans, avoiding possible harmful effects on the body. Mixed reality is widely used, considering that the environment and gases are virtual and real small robots. Essential components for the experiments are virtual, such as gases and BioCyber-Sensors. The results establish the great potential for applications in several areas, such as industrial, biomedical, and services. The entire system was developed based on ROS (Robot Operating System), thus the ease in diversifying different applications and approaches with multiple agents. The main objective of small robots is to guaranty a healthy work environment.

This paper aims to present an automated experimentation platform designed to work with multiple m... more This paper aims to present an automated experimentation platform designed to work with multiple mobile robots into industrial scenarios using Robot Operating System (ROS). Robot swarm is a system with complexity proportional of group size, expensive and with arduous setup. Virtual environments can be used to expedite the testing, but also are very difficult due to a hard-work to configure each robot. The proposed platform is a tool set to easily configure the experimentation environment, aiming the swarm tasks, with most popular perception systems, absolute or relative localization reference, and position controllers. The user specifies in tool only the amount of robots required, sensor and function, without having to configure each robot individually for the simulation. This paper presents examples to multi-robot setup in industrial scenarios, through a simple parameterization script. The memory consumption is demystified to given to allow the estimation of computational resources ...

2020 IEEE International Conference on Industrial Technology (ICIT), 2020

In this paper is presented the design, construction and evaluation of an autonomous mobile robot,... more In this paper is presented the design, construction and evaluation of an autonomous mobile robot, designed to outdoor competitions. The category of outdoor competition, in Brazil named Trekking Pro, is based on a mobile robot in an open field, which must pass through preset coordinates. A commercial (at first remote controlled) robot was adapted for autonomous operation. The perception of the robot consists of 9-axis Absolute Orientation Sensor and an encoder. At fist, the system was simulated in a ROS (Robotic Operation System) environment integrated with a scene V-REP (Virtual Robot Experimentation Platform). PID controllers, were used in implementation. Afterwards, a prototype was built, that participated in a competition with success, winning the first place. Both simulation and real-world experimental results of the constructed prototype are shown in detail. The robot described in this paper was the champion of the Winter Challenge 2018 (Robocore - Brazil) in the Trekking Pro c...

IEEE Sensors Journal, 2021

This paper discusses a novel collective sensing approach using autonomous sensors specially desig... more This paper discusses a novel collective sensing approach using autonomous sensors specially designed to monitor gas leaks and search for gas sources. The proposed collective behavior aims to improve the gas-source search by sharing information between mobile sensors and reducing the risks associated with gas leakage. The group acts as a composite sensor that can move independently to search for an optimal sensing zone. The autonomous searching behavior is bio-inspired by colonies of bacteria that continuously seek energy sources throughout their existence. Each sensor makes its own autonomous search decision, considering the group sense, to move in the direction of a better energy source. The collective approach is based on autonomous agents sharing information to achieve a collective sense of gas perception and utilizes more intelligent searching. The method is evaluated in a cyber-physical system specially developed to safely experiment with gases and mobile sensors while reproduc...

2020 IEEE 18th International Conference on Industrial Informatics (INDIN), 2020

Modern industry demands techniques that ensure the operability of its processes, and even though ... more Modern industry demands techniques that ensure the operability of its processes, and even though the exponential technological advance in the last two decades in the manufacturing field, failures, waste, and unexpected interruptions are still present in this sector's daily routine. Within the Industry 4.0 context, fault-tolerant (FT) production systems remain a complex issue and sometimes represent a vulnerable aspect. Fault-tolerance techniques dedicated to autonomous and distributed systems, in a cyber-physical system (CPS) perspective, need to be investigated to follow the evolutionary pace of the manufacturing scenarios. This paper overviews these concepts and analyses the current situation in developing FT for CPS systems through a systematic literature review. The paper also discusses the research challenges in this new kind of FT systems due to new distributed architectures and emerging technologies, matching the several fault- tolerance phases.

Abstract. This paper discusses an improvement for an autonomous robot’s magnetic climbing system ... more Abstract. This paper discusses an improvement for an autonomous robot’s magnetic climbing system necessary to perform the inspection of metal plates and weld beads in internal/external LPG storage sphere’s surfaces. This task typically covers up to 360◦ in the roll-pitch-yaw angles navigation with respect to the Earth‘s surface plan. Also, the storage spheres’ metal surfaces present non-modeled disturbances (such as surface irregularities, rust dust, welding seams...) that can change the adhesion force, requiring an active control to maintain the force balance needed for trajectory tracking. Classic approaches utilize distance sensors to detect gaps between the wheel and the surface, providing a low-level feedback to the control system that, generally, does not have an active compensation of adhesion, thus, disturbing the robot navigation. Unfortunately this method is inappropriate due to the adhesion system’s nonlinear behavior (adhesion force between wheel and surface decreases ra...

This chapter aims to present a new ROS package to automate experimentation with multiple mobile r... more This chapter aims to present a new ROS package to automate experimentation with multiple mobile robots. A robot swarm is a specific system that requires a complicated setup and has a high cost with regard to experimentation. Virtual environments can be used to expedite testing; however, these also are very laborious. This package is a tool set to easily configure the experimentation environment for swarm tasks with the most popular perception systems and absolute or relative localization references. The user specifies in the tool only the number of robots required, sensors, and functions without having to configure each robot individually for the simulation. This chapter presents two examples of the developed package to show how the new package simplifies working with swarms of robots and focuses on the application rather than the required configuration. An example of a formation maintained through the fuzzy approach is developed to demonstrate the potential of the proposed package....

Sensors

Realizing autonomous inspection, such as that of power distribution lines, through unmanned aeria... more Realizing autonomous inspection, such as that of power distribution lines, through unmanned aerial vehicle (UAV) systems is a key research domain in robotics. In particular, the use of autonomous and semi-autonomous vehicles to execute the tasks of an inspection process can enhance the efficacy and safety of the operation; however, many technical problems, such as those pertaining to the precise positioning and path following of the vehicles, robust obstacle detection, and intelligent control, must be addressed. In this study, an innovative architecture involving an unmanned aircraft vehicle (UAV) and an unmanned ground vehicle (UGV) was examined for detailed inspections of power lines. In the proposed strategy, each vehicle provides its position information to the other, which ensures a safe inspection process. The results of real-world experiments indicate a satisfactory performance, thereby demonstrating the feasibility of the proposed approach.

Robot 2019: Fourth Iberian Robotics Conference, Nov 20, 2019

Sensors

This work proposes a novel semantic perception system based on computer vision andmachine learnin... more This work proposes a novel semantic perception system based on computer vision andmachine learning techniques. The main goal is to identify objects in the environment and extracttheir characteristics, allowing a dynamic interaction with the environment. The system is composedof a GPU processing source and a 3D vision sensor that provides RGB image and PointCloud data.The perception system is structured in three steps: Lexical Analysis, Syntax Analysis and finallyan Analysis of Anticipation. The Lexical Analysis detects the actual position of the objects (ortokens) in the environment, through the combination of RGB image and PointCloud, surveying theircharacteristics. All information extracted from the tokens will be used to retrieve relevant featuressuch as object velocity, acceleration and direction during the Syntax Analysis step. The anticipationstep predicts future behaviors for these dynamic objects, promoting an interaction with them interms of collisions, pull, and push actio...

Journal of Intelligent & Robotic Systems

This work presents a novel method to quasi-omnidirectional control of an intelligent inspection r... more This work presents a novel method to quasi-omnidirectional control of an intelligent inspection robot designed to work inside and outside spherical storage tanks. The main objective is to promote a stable and smooth navigation during inspection tasks, ensuring the safety motion under adhesion and kinematic constraints. The robot is designed with four independent steerable magnetic wheels and a mechanical topology that allows the correct adjustment of adhesion system. A scheduled Fuzzy control is developed to achieve an optimal behavior and maximize the robot’s maneuverability, considering the magnetic restrictions of adhesion system and kinematic constraints of the inspection robot. The high adaptability of its mechanical topology (i.e., wheel misalignment, magnetic adhesion system, wheel camber and flexibilities in mechanical structure) and gravitational disturbance introduce many nonlinear characteristics in dynamic behavior that cannot be neglected, making the determination of its dynamic model a complex task. The Fuzzy approach allows to project a control system without a depth knowledge of its dynamic properties, to minimize the dynamic disturbances found in robot structure. Thus, the proposed motion control works according to the robot specific characteristics to ensure the quasi-omnidirectional motion over a reliable adhesion to tank surface and to minimize the effects of wheels kinematic constraints.

Journal of Intelligent & Robotic Systems

This paper presents a novel approach to environment mapping prediction with focus on autonomous c... more This paper presents a novel approach to environment mapping prediction with focus on autonomous climbing robot to NDT (Non-Destructive Technique) inspection. In industrial installations, the inspection of non-planar surfaces requires that NDT probes passe on whole surface, while the autonomous robot navigates over an unknown environment based only on its perception abilities. However, the path planning of inspection is not a trivial task specially when there is no precise information about environment. In this work, a special kind of climbing robot is used to inspect large metallic surfaces such as spherical pressure vessels used to store Liquified Petroleum Gas (LPG). The robot has adherence skills that allow it to safely navigate through the internal and external surface of the vessel. As a result, robot mobility suffers from hard magnetic adhesion constraints. A new approach is proposed to environment detailed prediction, including specific characteristic (like weld beads and plates) of inspected surface. The goal is the automatic extraction of some environment characteristics to predict the storage tank dimensions and robot localization, based on a group of 3D perception sources (laser rangefinder, light detection and ranging and depth camera) mounted over a rolling platform to improve its reach. The environment prediction is carried out after the robot visually detects two or more weld beads corners. A multi-measuring environment is firstly build by Fuzzy data fusion of the different perception measurements allowing to estimate plates and weld beads based on design and safety standards. Virtual and real experiments are carried out to illustrate proposed method performance.

Robotica, 2015

SUMMARY Differential kinematics is a traditional approach to linearize the mapping between the wo... more SUMMARY Differential kinematics is a traditional approach to linearize the mapping between the workspace and joint space. However, a Jacobian matrix cannot be inverted directly in redundant systems or in configurations where kinematic singularities occur. This work presents a novel approach to the solution of differential kinematics through the use of dual quaternions. The main advantage of this approach is to reduce “drift” error in differential kinematics and to ignore the kinematic singularities. An analytical dual-quaternionic Jacobian is defined, which allows for the application of this approach in any robotic system.