Localization and Navigation of the CoBots Over Long-term Deployments

For the last three years, we have developed and researched multiple collaborative robots, CoBots, which have been autonomously traversing our multi-floor buildings. We pursue the goal of long-term autonomy for indoor service mobile robots as the ability for them to be deployed indefinitely while they perform tasks in an evolving environment. The CoBots include several levels of autonomy, and in this paper we focus on their localization and navigation algorithms. We present the Corrective Gradient Refinement (CGR) algorithm, which refines the proposal distribution of the particle filter used for localization with sensor observations using analytically computed state space derivatives on a vector map. We also present the Fast Sampling Plane Filtering (FSPF) algorithm that extracts planar regions from depth images in real time. These planar regions are then projected onto the 2D vector map of the building, and along with the laser rangefinder observations, used with CGR for localization. For navigation, we present a hierarchical planner, which computes a topological policy using a graph representation of the environment, computes motion commands based on the topological policy, and then modifies the motion commands to side-step perceived obstacles. The continuous deployments of the CoBots over the course of one and a half years have provided us with logs of the CoBots traversing more than 130km over 1082 deployments, which we publish as a dataset consisting of more than 10 million laser scans. The logs show that although there have been continuous changes in the environment, the robots are robust to most of them, and there exist only a few locations where changes in the environment cause increased uncertainty in localization

Modelado de sensores piezoresistivos y uso de una interfaz basada en guantes de datos para el control de impedancia de manipuladores robóticos

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Arquitectura de Computadores y Automática, leída el 21-02-2014Sección Deptal. de Arquitectura de Computadores y Automática (Físicas)Fac. de Ciencias FísicasTRUEunpu

Development of a methodology for the human-robot interaction based on vision systems for collaborative robotics

L'abstract è presente nell'allegato / the abstract is in the attachmen

Smart working technologies in industry 4.0 : contributions to different manufacturing activities and workers’ skills

A Indústria 4.0 é considerada a quarta revolução industrial porque utiliza uma ampla integração de tecnologias de informação e de operação na fabricação industrial. Apesar dessa perspectiva tecnológica, diversos estudos vêm evidenciando a importância de considerar o fator humano para o desenvolvimento de um sistema de manufatura inteligente. Nesse sentido, a dimensão denominada como Smart Working precisa ser melhor investigada, uma vez que entender como as tecnologias afetam os trabalhadores e as habilidades desses são cruciais para o bom desempenho das fábricas. Em razão disso, o objetivo desta dissertação foi entender como as Smart Working Technologies (SWT) podem contribuir para as atividades e as habilidades dos trabalhadores da manufatura. Para tanto, primeiramente foi realizada uma análise abrangente da literatura para identificar as SWT e seus impactos nas capacidades dos trabalhadores em suas atividades de manufatura. Deste modo, foram analisados 80 artigos que relacionam as SWT em oito atividades de manufatura. Posteriormente, foi selecionada uma das SWT mais relevantes conforme a literatura, os robôs colaborativos, para identificar os efeitos das tecnologias nas habilidades dos trabalhadores. Deste modo, foram analisados 138 casos de aplicação reportados por uma das empresas fornecedoras líderes mundiais, bem como três entrevistas com empresas adotantes da tecnologia. Os resultados apontam que existem 15 SWT que podem ser implementadas nas atividades de manufatura e relacionadas às capacidades dos trabalhadores. Além disso, os resultados também apontam que podem existir quatro efeitos das SWT nas habilidades dos trabalhadores. Estes achados demonstram que de acordo com a estratégia da empresa uma SWT pode impactar de diferentes formas os trabalhadores.Industry 4.0 is considered the fourth industrial revolution because it uses a broad integration of information and operating technologies in industrial manufacturing. Despite this technological perspective, several studies have highlighted the importance of considering the human factor to develop a smart manufacturing system. In this sense, the Smart Working dimension needs to be further investigated since understanding how technologies affect workers and their skills are crucial for factories' good performance. Therefore, the objective of this dissertation was to understand how Smart Working Technologies (SWT) can contribute to the activities and skills of manufacturing workers. To this end, firstly a systematic literature review was carried out to identify SWTs and their impacts on workers' capabilities in their manufacturing activities. Thus, 80 articles relating to SWT in eight manufacturing activities were analyzed. Subsequently, one of the most relevant SWTs according to the literature, collaborative robots, was selected to identify the effects of technologies on workers' skills. In this way, 138 application cases reported by one of the world's leading supplier companies were analyzed, as well as three interviews with companies that adopted the technology. The results show that there are 15 SWT that can be implemented in manufacturing activities and related to workers' capabilities. In addition, the results also point out that there may be four effects of SWT on workers' skills. According to the company's strategy, these findings demonstrate that an SWT can impact workers in different ways

Intuitive, iterative and assisted virtual guides programming for human-robot comanipulation

Pendant très longtemps, l'automatisation a été assujettie à l'usage de robots industriels traditionnels placés dans des cages et programmés pour répéter des tâches plus ou moins complexes au maximum de leur vitesse et de leur précision. Cette automatisation, dite rigide, possède deux inconvénients majeurs : elle est chronophage dû aux contraintes contextuelles applicatives et proscrit la présence humaine. Il existe désormais une nouvelle génération de robots avec des systèmes moins encombrants, peu coûteux et plus flexibles. De par leur structure et leurs modes de fonctionnement ils sont intrinsèquement sûrs ce qui leurs permettent de travailler main dans la main avec les humains. Dans ces nouveaux espaces de travail collaboratifs, l'homme peut être inclus dans la boucle comme un agent décisionnel actif. En tant qu'instructeur ou collaborateur il peut influencer le processus décisionnel du robot : on parle de robots collaboratifs (ou cobots). Dans ce nouveau contexte, nous faisons usage de guides virtuels. Ils permettent aux cobots de soulager les efforts physiques et la charge cognitive des opérateurs. Cependant, la définition d'un guide virtuel nécessite souvent une expertise et une modélisation précise de la tâche. Cela restreint leur utilité aux scénarios à contraintes fixes. Pour palier ce problème et améliorer la flexibilité de la programmation du guide virtuel, cette thèse présente une nouvelle approche par démonstration : nous faisons usage de l'apprentissage kinesthésique de façon itérative et construisons le guide virtuel avec une spline 6D. Grâce à cette approche, l'opérateur peut modifier itérativement les guides tout en gardant leur assistance. Cela permet de rendre le processus plus intuitif et naturel ainsi que de réduire la pénibilité. La modification locale d'un guide virtuel en trajectoire est possible par interaction physique avec le robot. L'utilisateur peut déplacer un point clé cartésien ou modifier une portion entière du guide avec une nouvelle démonstration partielle. Nous avons également étendu notre approche aux guides virtuels 6D, où les splines en déplacement sont définies via une interpolation Akima (pour la translation) et une 'interpolation quadratique des quaternions (pour l'orientation). L'opérateur peut initialement définir un guide virtuel en trajectoire, puis utiliser l'assistance en translation pour ne se concentrer que sur la démonstration de l'orientation. Nous avons appliqué notre approche dans deux scénarios industriels utilisant un cobot. Nous avons ainsi démontré l'intérêt de notre méthode qui améliore le confort de l'opérateur lors de la comanipulation.For a very long time, automation was driven by the use of traditional industrial robots placed in cages, programmed to repeat more or less complex tasks at their highest speed and with maximum accuracy. This robot-oriented solution is heavily dependent on hard automation which requires pre-specified fixtures and time consuming programming, hindering robots from becoming flexible and versatile tools. These robots have evolved towards a new generation of small, inexpensive, inherently safe and flexible systems that work hand in hand with humans. In these new collaborative workspaces the human can be included in the loop as an active agent. As a teacher and as a co-worker he can influence the decision-making process of the robot. In this context, virtual guides are an important tool used to assist the human worker by reducing physical effort and cognitive overload during tasks accomplishment. However, the construction of virtual guides often requires expert knowledge and modeling of the task. These limitations restrict the usefulness of virtual guides to scenarios with unchanging constraints. To overcome these challenges and enhance the flexibility of virtual guides programming, this thesis presents a novel approach that allows the worker to create virtual guides by demonstration through an iterative method based on kinesthetic teaching and displacement splines. Thanks to this approach, the worker is able to iteratively modify the guides while being assisted by them, making the process more intuitive and natural while reducing its painfulness. Our approach allows local refinement of virtual guiding trajectories through physical interaction with the robots. We can modify a specific cartesian keypoint of the guide or re- demonstrate a portion. We also extended our approach to 6D virtual guides, where displacement splines are defined via Akima interpolation (for translation) and quadratic interpolation of quaternions (for orientation). The worker can initially define a virtual guiding trajectory and then use the assistance in translation to only concentrate on defining the orientation along the path. We demonstrated that these innovations provide a novel and intuitive solution to increase the human's comfort during human-robot comanipulation in two industrial scenarios with a collaborative robot (cobot)

Collaborative Robotic Path Planning for Industrial Spraying Operations on Complex Geometries

Implementation of automated robotic solutions for complex tasks currently faces a few major hurdles. For instance, lack of effective sensing and task variability – especially in high-mix/low-volume processes – creates too much uncertainty to reliably hard-code a robotic work cell. Current collaborative frameworks generally focus on integrating the sensing required for a physically collaborative implementation. While this paradigm has proven effective for mitigating uncertainty by mixing human cognitive function and fine motor skills with robotic strength and repeatability, there are many instances where physical interaction is impractical but human reasoning and task knowledge is still needed. The proposed framework consists of key modules such as a path planner, path simulator, and result simulator. An integrated user interface facilitates the operator to interact with these modules and edit the path plan before ultimately approving the task for automatic execution by a manipulator that need not be collaborative. Application of the collaborative framework is illustrated for a pressure washing task in a remanufacturing environment that requires one-off path planning for each part. The framework can also be applied to various other tasks, such as spray-painting, sandblasting, deburring, grinding, and shot peening. Specifically, automated path planning for industrial spraying operations offers the potential to automate surface preparation and coating in such environments. Autonomous spray path planners in the literature have been limited to generally continuous and convex surfaces, which is not true of most real parts. There is a need for planners that consistently handle concavities and discontinuities, such as sharp corners, holes, protrusions or other surface abnormalities when building a path. The path planner uses a slicing-based method to generate path trajectories. It identifies and quantifies the importance of concavities and surface abnormalities and whether they should be considered in the path plan by comparing the true part geometry to the convex hull path. If necessary, the path is then adapted by adjusting the movement speed or offset distance at individual points along the path. Which adaptive method is more effective and the trade-offs associated with adapting the path are also considered in the development of the path planner

The design and control of an actively restrained passive mechatronic system for safety-critical applications

Development of manipulators that interact closely with humans has been a focus of research in fields such as robot-assisted surgery and haptic interfaces for many years. Recent introduction of powered surgical-assistant devices into the operating theatre has meant that robot manipulators have been required to interact with both patients and surgeons. Most of these manipulators are modified industrial robots. However, the use of high-powered mechanisms in the operating theatre could compromise safety of the patient, surgeon, and operating room staff. As a solution to the safety problem, the use of actively restrained passive arms has been proposed. Clutches or brakes at each joint are used to restrict the motion of the end-effector to restrain it to a pre-defined region or path. However, these devices have only had limited success in following pre-defined paths under human guidance. In this research, three major limitations of existing passive devices actively restrained are addressed. [Continues.