3D point cloud registration based on a purpose-designed similarity measure

This article introduces a novel approach for finding a rigid transformation that coarsely aligns two 3D point clouds. The algorithm performs an iterative comparison between 2D descriptors by using a purpose-designed similarity measure in order to find correspondences between two 3D point clouds sensed from different positions of a free-form object. The descriptors (named with the acronym CIRCON) represent an ordered set of radial contours that are extracted around an interest-point within the point cloud. The search for correspondences is done iteratively, following a cell distribution that allows the algorithm to converge toward a candidate point. Using a single correspondence an initial estimation of the Euclidean transformation is computed and later refined by means of a multiresolution approach. This coarse alignment algorithm can be used for 3D modeling and object manipulation tasks such as "Bin Picking" when free-form objects are partially occluded or present symmetries

Working together: a review on safe human-robot collaboration in industrial environments

After many years of rigid conventional procedures of production, industrial manufacturing is going through a process of change toward flexible and intelligent manufacturing, the so-called Industry 4.0. In this paper, human-robot collaboration has an important role in smart factories since it contributes to the achievement of higher productivity and greater efficiency. However, this evolution means breaking with the established safety procedures as the separation of workspaces between robot and human is removed. These changes are reflected in safety standards related to industrial robotics since the last decade, and have led to the development of a wide field of research focusing on the prevention of human-robot impacts and/or the minimization of related risks or their consequences. This paper presents a review of the main safety systems that have been proposed and applied in industrial robotic environments that contribute to the achievement of safe collaborative human-robot work. Additionally, a review is provided of the current regulations along with new concepts that have been introduced in them. The discussion presented in this paper includes multidisciplinary approaches, such as techniques for estimation and the evaluation of injuries in human-robot collisions, mechanical and software devices designed to minimize the consequences of human-robot impact, impact detection systems, and strategies to prevent collisions or minimize their consequences when they occur

Dynamic positioning of floating caissons based on the UKF filter under external perturbances induced by waves

This paper presents a dynamic positioning control scheme for concrete caissons in an attempt to automate part of the manoeuvres which usually require a complex deploy of personnel and equipment for port infrastructures development. The aim of this paper is to propose a control scheme, which is able to provide a reduction in costs and an improvement in security for the dynamic positioning manoeuvres . To do so, a dual loop controller is developed and the unscented Kalman filter is applied for states and perturbances estimation. Furthermore, a control allocation algorithm is proposed based on anchoring lines and winches. Finally, some simulations are performed to verify the effectiveness of the proposed approach.The Spanish FEDER/Ministry of Science, Innovation and Universities — State Research Agency (Fig. 14) is greatly acknowledged for funding our research through SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), Grant Agreement: RTC-2017-6603-4. The authors would like to thank FCC CO as a collaborator in the development of the SAFE Project. R. Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities

LQG control for dynamic positioning of floating caissons based on the Kalman filter

This paper presents the application of an linear quadratic gaussian (LQG) control strategy for concrete caisson deployment for marine structures. Currently these maneuvers are carried out manually with the risk that this entails. Control systems for these operations with classical regulators have begun to be implemented. They try to reduce risks, but they still need to be optimized due to the complexity of the dynamics involved during the sinking process and the contact with the sea bed. A linear approximation of the dynamic model of the caisson is obtained and an LQG control strategy is implemented based on the Kalman filter (KF). The results of the proposed LQG control strategy are compared to the ones given by a classic controller. It is noted that the proposed system is positioned with greater precision and accuracy, as shown in the different simulations and in the Monte Carlo study. Furthermore, the control efforts are less than with classical regulators. For all the reasons cited above, it is concluded that there is a clear improvement in performance with the control system proposed.The Spanish FEDER/Ministry of Science, Innovation and Universities—State Research Agency is greatly acknowledged for partially funding our research through the SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), GrantAgreement: RTC-2017-6603-4. The Regional Ministry of Universities, Equality, Culture and Sports of the Gov-ernment of Cantabria has supported this work through the ControlFond project (Control De Ve-hículos Subacuáticos No Tripulados Para Supervisión De Estructuras Para Obras Marítimas Fondeadas). The authors would like to thank FCC Construcción CO as a collaborator in the de-velopment of the SAFE Project, specially Victor Florez Casillas and Nuria Cotallo Aguado (Tech-nical Direction/Hydraulic and Maritime Works) and Alvaro de Toro Mingo (Machinery Direction). R. Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities

Sistema de visión ultrasónica para invidentes

Consiste en unas gafas en cuyas patillas van alojados unos pequeños sensores de ultrasonidos, que van conectados a una unidad autónoma que procesa la información de estos sensores y proporciona una señal, bien de presión, acústica o vibratoria, a la persona invidente que las lleva advirtiendo de la presencia y orientación de cualquier cuerpo u objeto situado en un entorno cercano, incluyendo estructuras tipo andamio que resultan muy peligrosas para estas personas.Solicitud: 009901199 (27.05.1999)Nº Pub. de Solicitud: ES2158786A1 (01.09.2001)Nº de Patente: ES2158786B1 (16.03.2002

Aplicación de inteligencia artificial en sistemas automatizados de producción

“Soy un gigante tan gigante que puedo grabar una rosa en la uña de un niño recién nacido”. Para solucionar el problema el personaje de García Lorca puede emplear diferentes métodos o múltiples paradigmas, como haría un sistema de inteligencia artificial. La inteligencia artificial es “simplemente” la transferencia de la inteligencia a las máquinas, es decir que el computador haga cosas inteligentes. Sin embargo la inteligencia humana es una función tan compleja que los científicos están solo empezando a comprender. Como los sistemas de inteligencia artificial, el personaje seguramente posee un conocimiento concreto de hechos y factores que afectan al problema y un conocimiento abstracto de reglas e ideas para solucionarlo, y su éxito depende de la habilidad de aplicar este conocimiento a cualquier situación, y de aprender continuamente de nuevas experiencias. Las reglas que relacionan todos los hechos conocidos están expresadas por relaciones condicionales y de la misma manera que el ser humano, puede procesar un gran número de impresiones sensoriales que le llegan al mismo tiempo y que son irrelevantes al problema. Mediante un sofisticado proceso de selección debe eliminar los caminos de razonamiento que no son vitales para resolver el problema concreto. El objetivo final se alcanza cumpliendo una serie de metas intermedias, ya que sin objetivos que lograr no existe razón para pensar, es decir, “no hacemos cosas porque pensamos sino que pensamos porque hay cosas que tenemos que hacer”. Las técnicas de inteligencia artificial son capaces tanto de sustituir elementos tradicionales de control como de realizar tareas que hasta el momento era imposible abordar sin la presencia del operador humano. Se presentan a continuación una serie de aplicaciones en las que el Grupo de Ingeniería de Control de la Universidad de Cantabria ha empleado herramientas de inteligencia artificial para aplicaciones de automatización y control de sistemas complejos

Técnicas avanzadas de identificación y reconstrucción de objetos mediante ultrasonidos

El presente trabajo se centra, apoyándose en la información proporcionada por los sensores de ultrasonidos, por una parte en la resolución de ciertos problemas habituales en los procesos automatizados en los que se requiere obtener información de determinados objetos para facilitar su manipulación, así como por otra parte en la resolución de problemas en el reconocimiento del entorno para su aplicación en la navegación autónoma de robots en entornos estructurados. Para las tareas de clasificación y reconstrucción de objetos se han empleado técnicas de inteligencia artificial tales como las redes neuronales y la lógica borrosa. Y para las tareas de reconocimiento y localización de paredes y esquinas se ha desarrollado un modelo que permite generar la respuesta espacial y temporal de los ultrasonidos ante este tipo de superficies y su aplicación, empleando algoritmos genéticos, para la resolución del problema inverso de localización de esquinas partiendo de la información ultrasónica recibida

Educación en automática e industria 4.0 mediante la aplicación de tecnologías 3D

[Resumen] El presente trabajo se centra en la utilización de tecnologías 3D, y más concretamente de sistemas de gestión de ciclo de vida del producto (sistemas PLM) de tipo industrial, como plataformas de enseñanza virtual colaborativa para la formación en automática de estudiantes de las titulaciones universitarias de grado y/o máster con contenidos en automática y, especialmente, para las titulaciones relacionadas con la ingeniería industrial. Se muestra como los modernos sistemas PLM no solo permiten desarrollar competencias vinculadas al trabajo en grupo colaborativo y concurrente, si no que, además, permiten diseñar y experiencias prácticas formativas vinculadas con los contenidos propios de las asignaturas de ingeniería de sistemas y automática, al tiempo que se está formando al alumno un entorno cada vez más empleado en ingeniería y que es pieza clave en la industria del futuro (IoF) o industria 4.0 (I4.0)

Gain scheduling model predictive control for dynamic positioning of floating caissons at different draughts

This article presents a model predictive control for dynamic positioning (DP) of floating caisson at different draughts. This article focuses on the maneuvres related to the control of the spatial situation of the caisson in connexion with the final caisson reference point and the process of descending to the seabed desired location. Different models of the caisson in order to perform realistic simulations and to test the robustness of the controller are considered. A gain scheduling model predictive control (GSMPC) has been implemented, with parameter switch among four model predictive control (MPC) controllers. In this way, a specific MPC for the dynamics of each draught will be used in each caisson model corresponding to a draught. Furthermore, a Kalman filter has been implemented to remove the disturbances. Finally, in the simulations results it is compared the performance of the proposed controller with a clasic one and also it is checked how the proposed controller is able to position the system in all draughts with stability and accurate dynamic control of the system.The Spanish FEDER/Ministry of Science, Innovation and Universities–State Research Agency has partially supported through the SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), Grant Agreement: Proyecto RTC-2017-6603-4 financiado por MCIN/AEI/10.13039/501100011033 y FEDER “Una manera de hacer Europa”. The Regional Ministry of Universities, Equality, Culture and Sports of the Government of Cantabria has provided partial support through the ControlFond project (Control De Vehículos Subacuáticos No Tripulados Para Supervisión De Estructuras Para Obras Marítimas Fondeadas). The authors would like to thank FCC Construcción S.A. as a collaborator in the development of the SAFE Project, specially Victor Florez Casillas and Nuria Cotallo Aguado (Technical Direction/Hydraulic and Maritime Works) and Alvaro de Toro Mingo (Machinery Direction). Raul Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities. Ayuda RYC-2017- 23260 financiada por MCIN/AEI/10.13039/501100011033 y FSE “El FSE invierte en tu futuro”

Design and Validation of a Questionnaire on Risk Perception, Coping Behaviors and Preventive Knowledge against COVID-19 among Nursing Students

As shown in the previous literature, in view of the future responsibilities of nursing professionals and the consequences for healthcare, it is of great interest to examine their risk perceptions, coping behaviors, and sense of coherency during the COVID-19 pandemic. The purpose of this study is to design and to validate a specific questionnaire that evaluates the factors relating to perceived risk, coping behaviors, and preventive knowledge against COVID-19 infection among nursing students from Spain. This is a psychometric study of a questionnaire's design and its validation in 1562 nursing students at 16 undergraduate nursing institutions in Spain. An ad-hoc survey was designed by a panel of six experts drawing from the literature. After a trial test, the questionnaire was formed with four scales (perception, risk, coping, and knowledge of preventive practices for COVID-19), with a total of 69 items. The final questionnaire was composed of 52 items grouped into four scales, with good psychometric properties to measure risk perception (Cronbach's alpha 0.735), factors related to perceived risk (Cronbach's alpha 0.653), coping behaviors (Cronbach's alpha 0.80), and knowledge of preventive practices against COVID-19 (Cronbach's alpha 0.77). This questionnaire, specifically designed and validated for nursing students, is the first to address four important areas in the development of preventive measures against COVID-19.This research was funding by the Fundación Instituto de InvestigaciónMarqués De Valdecilla.Nursing educationNursing studentsRisk assessmen