Hierarchical Reactive Control for Soccer Playing Humanoid Robots

What drives thousands of researchers worldwide to devote their creativity and energy t

Humanoid Robot Soccer Locomotion and Kick Dynamics: Open Loop Walking, Kicking and Morphing into Special Motions on the Nao Robot

Striker speed and accuracy in the RoboCup (SPL) international robot soccer league is becoming increasingly important as the level of play rises. Competition around the ball is now decided in a matter of seconds. Therefore, eliminating any wasted actions or motions is crucial when attempting to kick the ball. It is common to see a discontinuity between walking and kicking where a robot will return to an initial pose in preparation for the kick action. In this thesis we explore the removal of this behaviour by developing a transition gait that morphs the walk directly into the kick back swing pose. The solution presented here is targeted towards the use of the Aldebaran walk for the Nao robot. The solution we develop involves the design of a central pattern generator to allow for controlled steps with realtime accuracy, and a phase locked loop method to synchronise with the Aldebaran walk so that precise step length control can be activated when required. An open loop trajectory mapping approach is taken to the walk that is stabilized statically through the use of a phase varying joint holding torque technique. We also examine the basic princples of open loop walking, focussing on the commonly overlooked frontal plane motion. The act of kicking itself is explored both analytically and empirically, and solutions are provided that are versatile and powerful. Included as an appendix, the broader matter of striker behaviour (process of goal scoring) is reviewed and we present a velocity control algorithm that is very accurate and efficient in terms of speed of execution

Locomotion system for ground mobile robots in uneven and unstructured environments

One of the technology domains with the greatest growth rates nowadays is service robots. The extensive use of ground mobile robots in environments that are unstructured or structured for humans is a promising challenge for the coming years, even though Automated Guided Vehicles (AGV) moving on flat and compact grounds are already commercially available and widely utilized to move components and products inside indoor industrial buildings. Agriculture, planetary exploration, military operations, demining, intervention in case of terrorist attacks, surveillance, and reconnaissance in hazardous conditions are important application domains. Due to the fact that it integrates the disciplines of locomotion, vision, cognition, and navigation, the design of a ground mobile robot is extremely interdisciplinary. In terms of mechanics, ground mobile robots, with the exception of those designed for particular surroundings and surfaces (such as slithering or sticky robots), can move on wheels (W), legs (L), tracks (T), or hybrids of these concepts (LW, LT, WT, LWT). In terms of maximum speed, obstacle crossing ability, step/stair climbing ability, slope climbing ability, walking capability on soft terrain, walking capability on uneven terrain, energy efficiency, mechanical complexity, control complexity, and technology readiness, a systematic comparison of these locomotion systems is provided in [1]. Based on the above-mentioned classification, in this thesis, we first introduce a small-scale hybrid locomotion robot for surveillance and inspection, WheTLHLoc, with two tracks, two revolving legs, two active wheels, and two passive omni wheels. The robot can move in several different ways, including using wheels on the flat, compact ground,[1] tracks on soft, yielding terrain, and a combination of tracks, legs, and wheels to navigate obstacles. In particular, static stability and non-slipping characteristics are considered while analyzing the process of climbing steps and stairs. The experimental test on the first prototype has proven the planned climbing maneuver’s efficacy and the WheTLHLoc robot's operational flexibility. Later we present another development of WheTLHLoc and introduce WheTLHLoc 2.0 with newly designed legs, enabling the robot to deal with bigger obstacles. Subsequently, a single-track bio-inspired ground mobile robot's conceptual and embodiment designs are presented. This robot is called SnakeTrack. It is designed for surveillance and inspection activities in unstructured environments with constrained areas. The vertebral column has two end modules and a variable number of vertebrae linked by compliant joints, and the surrounding track is its essential component. Four motors drive the robot: two control the track motion and two regulate the lateral flexion of the vertebral column for steering. The compliant joints enable limited passive torsion and retroflection of the vertebral column, which the robot can use to adapt to uneven terrain and increase traction. Eventually, the new version of SnakeTrack, called 'Porcospino', is introduced with the aim of allowing the robot to move in a wider variety of terrains. The novelty of this thesis lies in the development and presentation of three novel designs of small-scale mobile robots for surveillance and inspection in unstructured environments, and they employ hybrid locomotion systems that allow them to traverse a variety of terrains, including soft, yielding terrain and high obstacles. This thesis contributes to the field of mobile robotics by introducing new design concepts for hybrid locomotion systems that enable robots to navigate challenging environments. The robots presented in this thesis employ modular designs that allow their lengths to be adapted to suit specific tasks, and they are capable of restoring their correct position after falling over, making them highly adaptable and versatile. Furthermore, this thesis presents a detailed analysis of the robots' capabilities, including their step-climbing and motion planning abilities. In this thesis we also discuss possible refinements for the robots' designs to improve their performance and reliability. Overall, this thesis's contributions lie in the design and development of innovative mobile robots that address the challenges of surveillance and inspection in unstructured environments, and the analysis and evaluation of these robots' capabilities. The research presented in this thesis provides a foundation for further work in this field, and it may be of interest to researchers and practitioners in the areas of robotics, automation, and inspection. As a general note, the first robot, WheTLHLoc, is a hybrid locomotion robot capable of combining tracked locomotion on soft terrains, wheeled locomotion on flat and compact grounds, and high obstacle crossing capability. The second robot, SnakeTrack, is a small-size mono-track robot with a modular structure composed of a vertebral column and a single peripherical track revolving around it. The third robot, Porcospino, is an evolution of SnakeTrack and includes flexible spines on the track modules for improved traction on uneven but firm terrains, and refinements of the shape of the track guidance system. This thesis provides detailed descriptions of the design and prototyping of these robots and presents analytical and experimental results to verify their capabilities

Transport coopératif d'un objet par deux robots humanoïdes dans un environnement encombré

Il y a présentement de la demande dans plusieurs milieux cherchant à utiliser des robots afin d'accomplir des tâches complexes, par exemple l'industrie de la construction désire des travailleurs pouvant travailler 24/7 ou encore effectuer des operation de sauvetage dans des zones compromises et dangereuses pour l'humain. Dans ces situations, il devient très important de pouvoir transporter des charges dans des environnements encombrés. Bien que ces dernières années il y a eu quelques études destinées à la navigation de robots dans ce type d'environnements, seulement quelques-unes d'entre elles ont abordé le problème de robots pouvant naviguer en déplaçant un objet volumineux ou lourd. Ceci est particulièrement utile pour transporter des charges ayant de poids et de formes variables, sans avoir à modifier physiquement le robot. Un robot humanoïde est une des plateformes disponibles afin d'effectuer efficacement ce type de transport. Celui-ci a, entre autres, l'avantage d'avoir des bras et ils peuvent donc les utiliser afin de manipuler précisément les objets à transporter. Dans ce mémoire de maîtrise, deux différentes techniques sont présentées. Dans la première partie, nous présentons un système inspiré par l'utilisation répandue de chariots de fortune par les humains. Celle-ci répond au problème d'un robot humanoïde naviguant dans un environnement encombré tout en déplaçant une charge lourde qui se trouve sur un chariot de fortune. Nous présentons un système de navigation complet, de la construction incrémentale d'une carte de l'environnement et du calcul des trajectoires sans collision à la commande pour exécuter ces trajectoires. Les principaux points présentés sont : 1) le contrôle de tout le corps permettant au robot humanoïde d'utiliser ses mains et ses bras pour contrôler les mouvements du système à chariot (par exemple, lors de virages serrés) ; 2) une approche sans capteur pour automatiquement sélectionner le jeu approprié de primitives en fonction du poids de la charge ; 3) un algorithme de planification de mouvement qui génère une trajectoire sans collisions en utilisant le jeu de primitive approprié et la carte construite de l'environnement ; 4) une technique de filtrage efficace permettant d'ignorer le chariot et le poids situés dans le champ de vue du robot tout en améliorant les performances générales des algorithmes de SLAM (Simultaneous Localization and Mapping) défini ; et 5) un processus continu et cohérent d'odométrie formés en fusionnant les informations visuelles et celles de l'odométrie du robot. Finalement, nous présentons des expériences menées sur un robot Nao, équipé d'un capteur RGB-D monté sur sa tête, poussant un chariot avec différentes masses. Nos expériences montrent que la charge utile peut être significativement augmentée sans changer physiquement le robot, et donc qu'il est possible d'augmenter la capacité du robot humanoïde dans des situations réelles. Dans la seconde partie, nous abordons le problème de faire naviguer deux robots humanoïdes dans un environnement encombré tout en transportant un très grand objet qui ne peut tout simplement pas être déplacé par un seul robot. Dans cette partie, plusieurs algorithmes et concepts présentés dans la partie précédente sont réutilisés et modifiés afin de convenir à un système comportant deux robot humanoides. Entre autres, nous avons un algorithme de planification de mouvement multi-robots utilisant un espace d'états à faible dimension afin de trouver une trajectoire sans obstacle en utilisant la carte construite de l'environnement, ainsi qu'un contrôle en temps réel efficace de tout le corps pour contrôler les mouvements du système robot-objet-robot en boucle fermée. Aussi, plusieurs systèmes ont été ajoutés, tels que la synchronisation utilisant le décalage relatif des robots, la projection des robots sur la base de leur position des mains ainsi que l'erreur de rétroaction visuelle calculée à partir de la caméra frontale du robot. Encore une fois, nous présentons des expériences faites sur des robots Nao équipés de capteurs RGB-D montés sur leurs têtes, se déplaçant avec un objet tout en contournant d'obstacles. Nos expériences montrent qu'un objet de taille non négligeable peut être transporté sans changer physiquement le robot

Development of behaviors for a simulated humanoid robot

Mestrado em Engenharia de Computadores e TelemáticaControlar um robô bípede com vários graus de liberdade é um desafio que recebe a atenção de vários investigadores nas áreas da biologia, física, electrotecnia, ciências de computadores e mecânica. Para que um humanóide possa agir em ambientes complexos, são necessários comportamentos rápidos, estáveis e adaptáveis. Esta dissertação está centrada no desenvolvimento de comportamentos robustos para um robô humanóide simulado, no contexto das competições de futebol robótico simulado 3D do RoboCup, para a equipa FCPortugal3D. Desenvolver tais comportamentos exige o desenvolvimento de métodos de planeamento de trajectórias de juntas e controlo de baixo nível. Controladores PID foram implementados para o controlo de baixo nível. Para o planeamento de trajectórias, quatro métodos foram estudados. O primeiro método apresentado foi implementado antes desta dissertação e consiste numa sequência de funções degrau que definem o ângulo desejado para cada junta durante o movimento. Um novo método baseado na interpolação de um seno foi desenvolvido e consiste em gerar uma trajectória sinusoidal durante um determinado tempo, o que resulta em transições suaves entre o ângulo efectivo e o ângulo desejado para cada junta. Um outro método que foi desenvolvido, baseado em séries parciais de Fourier, gera um padrão cíclico para cada junta, podendo ter múltiplas frequências. Com base no trabalho desenvolvido por Sven Behnke, um CPG para locomoção omnidireccional foi estudado em detalhe e implementado. Uma linguagem de definição de comportamentos é também parte deste estudo e tem como objectivo simplificar a definição de comportamentos utilizando os vários métodos propostos. Integrando o controlo de baixo nível e os métodos de planeamento de trajectórias, vários comportamentos foram criados para permitir a uma versão simulada do humanóide NAO andar em diferentes direcções, rodar, chutar a bola, apanhar a bola (guarda-redes) e levantar do chão. Adicionalmente, a optimização e geração automática de comportamentos foi também estudada, utilizado algoritmos de optimização como o Hill Climbing e Algoritmos Genéticos. No final, os resultados são comparados com as equipas de simulação 3D que reflectem o estado da arte. Os resultados obtidos são bons e foram capazes de ultrapassar uma das três melhores equipas simuladas do RoboCup em diversos aspectos como a velocidade a andar, a velocidade de rotação, a distância da bola depois de chutada, o tempo para apanhar a bola e o tempo para levantar do chão. ABSTRACT: Controlling a biped robot with several degrees of freedom is a challenging task that takes the attention of several researchers in the fields of biology, physics, electronics, computer science and mechanics. For a humanoid robot to perform in complex environments, fast, stable and adaptable behaviors are required. This thesis is concerned with the development of robust behaviors for a simulated humanoid robot, in the scope of the RoboCup 3D Simulated Soccer Competitions, for FCPortugal3D team. Developing such robust behaviors requires the development of methods for joint trajectory planning and low-level control. PID control were implemented to achieve low-level joint control. For trajectory planning, four methods were studied. The first presented method was implemented before this thesis and consists of a sequence of step functions that define the target angle of each joint during the movement. A new method based on the interpolation of a sine function was developed and consists of generating a sinusoidal shape during some amount of time, leading to smooth transitions between the current angle and the target angle of each joint. Another method developed, based on partial Fourier Series, generates a multi-frequency cyclic pattern for each joint. This method is very flexible and allows to completely control the angular positions and velocities of the joints. Based on the work of developed by Sven Behnke, a CPG for omnidirectional locomotion was studied in detail and implemented. A behavior definition language is also part of this study and aims at simplifying the definition of behaviors using the several proposed methods. By integrating the low-level control and the trajectory planning methods, several behaviors were created to allow a simulated version of the humanoid NAO to walk in different directions, turn, kick the ball, catch the ball (goal keeper) and get up from the ground. Furthermore, the automatic generation of gaits, through the use of optimization algorithms such as hill climbing and genetic algorithms, was also studied and tested. In the end, the results are compared with the state of the art teams of the RoboCup 3D simulation league. The achieved results are good and were able to overcome one of the state of the art simulated teams of RoboCup in several aspects such as walking velocity, turning velocity, distance of the ball when kicked, time to catch the ball and the time to get up from the ground

Designing a robot to evaluate group formations

Robots are making their way in environments inhabited by people. Whether in domestic or public crowded environments, robots should take into consideration social norms and behaviors in order to become a social robot. This dissertation focuses on the problem of how to develop a robotic platform in order to validate human-robot interaction experiences in realistic environments. More specifically, we are concerned with social interactions in human-robot groups in public scenarios, where a variety of people can converge. Our final goal is the develop of a social robot based on certain theories of group behavior and the use of space, known as spatial relationships. The intermediate goals are related with the design and development of the experiences in the wild: as minor changes as possible in the scenario, definition of social tasks, gradual development of a robotic platform as transparent as possible from the robotic side. Initially, this research introduces several preliminary studies of human-robot interaction (HRI) with the PAL Robotics’ REEM robot at the CosmoCaixa Science Museum in Barcelona. Based on certain theories about the use of space as a form of social communication or interaction, the task under study with the commercial robot is as a museum guide, both when the group was in motion (\ie when it was being guided) as well as a group in a static place. Moreover, a second HRI study with REEM robot accomplishing the task of a teacher's assistant was carried out to analyze the perception of the robot's social presence and identity. Likewise, the development of a robotic platform, known as MASHI, for the study of HRI is presented. Based on the service to be completed by the robot, improvements in the experimental robotic platform (structure, morphology, head, face, arms) were carried out in continuous cycles following the development of HRI experiences. This structure should be hold as simple as possible in order to make it `transparent' in the social HRI study. Next, the field study of human-robot social interaction with the MASHI robot with the role of exhibition guide in a cultural center is presented. Based on direct observation techniques, a study is made of the different spatial relationships that are generated when a robot interacts with a person or groups of people. Finally, a novel approach to represent the spatial relationships of HRI in a qualitative way is introduced for future experiences. In this concluding study, we analyze different spatial arrangements generated in a social scenario with a robot within the guide role. As a main conclusion, it can be stated that people follow social norms, in the form of spatial relationships, when interacting with a robot that provide a social service in a public space. Children, however, recurrently challenge these social norms, probably because they are constantly learning about the norms that regulate our coexistence. Spatial relationships are clearly reinforced when the role assigned to the robot is more explicit and understood by people. Spatial relationships can be affected by the characteristics of the environment, either by the available space or by the elements arranged in it, as well as by the number of people who inhabit it. Overall, this dissertation points out that the provided service, and its understanding from the user’s side, is more important that the robotic skills of the robotic platform in order to improve user experiences in public environments.Los robots se abren paso en entornos habitados por personas. Ya sea en entornos domésticos o públicos, los robots deben tener en cuenta ciertas normas y comportamientos sociales para convertirse en un robot social. Esta disertación se centra en el problema de cómo desarrollar una plataforma robótica para validar experiencias de interacción humano-robot en entornos realistas. Más específicamente, nos preocupamos por las interacciones sociales en grupos humano-robot en escenarios públicos, donde una gran variedad de personas puede converger. Nuestro objetivo final es el desarrollo de un robot social basado en ciertas teorías de comportamiento grupal y el uso del espacio, conocidas como relaciones espaciales. Los objetivos intermedios están relacionados con el diseño y desarrollo de las experiencias `en la naturaleza': cambios mínimos como sea posible en el escenario, definición de tareas sociales, desarrollo gradual de una plataforma robótica lo más transparente posible desde el lado robótico. Inicialmente, esta investigación presenta varios estudios preliminares de interacción humano-robot (HRI) con el robot REEM de PAL Robotics en el Museo de Ciencias CosmoCaixa de Barcelona. Basado en ciertas teorías sobre el uso del espacio como una forma de comunicación o interacción social, la tarea en este estudio con el robot comercial es como guía de museo, tanto cuando el grupo estaba en movimiento (es decir, cuando estaba siendo guiado) como cuando el grupo estaba en un lugar estático. Además, se llevó a cabo un segundo estudio de HRI con un robot REEM que realizaba la tarea de un asistente de profesor para analizar la percepción de la presencia e identidad social del robot. Asimismo, se presenta el desarrollo de una plataforma robótica, conocida como MASHI, para el estudio de la HRI. En función del servicio que debe completar el robot, las mejoras en la plataforma robótica experimental (estructura, morfología, cabeza, cara, brazos) se llevaron a cabo en ciclos continuos siguiendo el desarrollo de las experiencias de HRI. Esta estructura debe mantenerse lo más simple posible para que sea 'transparente' en el estudio de HRI social. A continuación, se presenta el estudio de campo de la interacción social humano-robot con el robot MASHI con el papel de guía de exposición en un centro cultural. Con base en técnicas de observación directa, se realiza un estudio de las diferentes relaciones espaciales que se generan cuando un robot interactúa con una persona o grupos de personas. Finalmente, se introduce un enfoque novedoso para representar las relaciones espaciales de la HRI de forma cualitativa para las experiencias futuras. En este estudio final, analizamos diferentes arreglos espaciales generados en un escenario social con un robot con el rol de guía. Como conclusión principal, se puede afirmar que las personas siguen normas sociales, en forma de relaciones espaciales, cuando interactúan con un robot que brinda un servicio social en un espacio público. Los niños, sin embargo, desafían recurrentemente estas normas sociales, probablemente porque están aprendiendo constantemente sobre las normas que regulan nuestra convivencia. Las relaciones espaciales se refuerzan claramente cuando el rol asignado al robot es más explícito y entendido por las personas. Las relaciones espaciales pueden verse afectadas por las características del entorno, ya sea por el espacio disponible o por los elementos dispuestos en él, así como por el número de personas que lo habitan. En general, esta disertación señala que el servicio prestado, y su comprensión del lado del usuario, es más importante que las habilidades robóticas de la plataforma robótica con el fin de mejorar las experiencias del usuario en entornos público