27 research outputs found
Non-Monotonic Reasoning on Board a Sony AIBO
Griffith Sciences, School of Information and Communication TechnologyFull Tex
Artificial Vision in the Nao Humanoid Robot
Projecte Final de Màster UPC realitzat en col.laboració amb l'Universitat Rovira i Virgili. Departament d'Enginyeria Informàtica i MatemàtiquesRobocup is an international robotic soccer competition held yearly to promote
innovative research and application in robotic intelligence. Nao humanoid robot
is the new RoboCup Standard Platform robot. This platform is the new Nao
robot designed and manufactured by the french company Aldebaran Robotics.
The new robot is an advanced platform for developing new computer vision and
robotics methods. This Master Thesis is oriented to the study of some fundamental
issues for the artificial vision in the Nao humanoid robots. In particular,
color representation models, real-time segmentation techniques, object detection
and visual sonar approaches are the computer vision techniques applied to Nao
robot in this Master Thesis. Also, Nao’s camera model, mathematical robot
kinematic and stereo-vision techniques are studied and developed. This thesis
also studies the integration between kinematic model and robot perception
model to perform RoboCup soccer games and RoboCup technical challenges.
This work is focused in the RoboCup environment but all computer vision and
robotics algorithms can be easily extended to another robotics fields
RoboCup@Home: commanding a service robot by natural language.
It was in the ancient Greece that myths were written and, among already there one
could nd the human desire of robotic servants. It was Hephaestus, god of technology,
blacksmiths, craftsmen and artisans who is said to have built robots to help him on
his workshop. This show how deep in our thoughts was this desire that one could nd
stories and tales of human-shaped machines that danced in china or inanimate materials
like mud that gave shape to golems in Jewish tradition.
In the renaissance, a lot of automata began to arise, beginning by Leonardo Da Vinci to
the artisans from China and Japan, mankind was trying to produce automatic machines,
sometimes for their own bene t, some other times to their delight and fascination.
But it wasn't until the digital era that the dream began to seem feasible. After millennia
of wondering of automated robots, computers showed that automatic calculus was
possible and from this, ideas of an automated mind arose. Theories for cognitive architectures
are born since the early stages of arti cial intelligence, cognitive architectures
that now are a reality.
Thanks to the technological advances and the knowledge about the mind, what once
was material for ctional tales, now is feasible and only matter of time. There is a lot of
research on robotics and cognition that is beginning to get coupled into what are called
"service robots".
In this thesis, I present a system that participates in a competition designed for this kind of robots. A competition that have on its basis the same dream that humans have had
all around the world for centuries: the cohabitation of humans and service automatons
Perceção e arquitectura de software para robótica móvel
Doutoramento em Ciências da ComputaçãoWhen developing software for autonomous mobile robots, one has to inevitably
tackle some kind of perception. Moreover, when dealing with agents
that possess some level of reasoning for executing their actions, there is the
need to model the environment and the robot internal state in a way that
it represents the scenario in which the robot operates.
Inserted in the ATRI group, part of the IEETA research unit at Aveiro
University, this work uses two of the projects of the group as test bed, particularly
in the scenario of robotic soccer with real robots. With the main
objective of developing algorithms for sensor and information fusion that
could be used e ectively on these teams, several state of the art approaches
were studied, implemented and adapted to each of the robot types.
Within the MSL RoboCup team CAMBADA, the main focus was the perception
of ball and obstacles, with the creation of models capable of providing
extended information so that the reasoning of the robot can be ever more
e ective. To achieve it, several methodologies were analyzed, implemented,
compared and improved.
Concerning the ball, an analysis of ltering methodologies for stabilization
of its position and estimation of its velocity was performed. Also, with the
goal keeper in mind, work has been done to provide it with information of
aerial balls.
As for obstacles, a new de nition of the way they are perceived by the vision
and the type of information provided was created, as well as a methodology
for identifying which of the obstacles are team mates. Also, a tracking
algorithm was developed, which ultimately assigned each of the obstacles a
unique identi er. Associated with the improvement of the obstacles perception,
a new algorithm of estimating reactive obstacle avoidance was created.
In the context of the SPL RoboCup team Portuguese Team, besides the inevitable
adaptation of many of the algorithms already developed for sensor
and information fusion and considering that it was recently created, the objective
was to create a sustainable software architecture that could be the
base for future modular development.
The software architecture created is based on a series of di erent processes
and the means of communication among them. All processes were created
or adapted for the new architecture and a base set of roles and behaviors
was de ned during this work to achieve a base functional framework.
In terms of perception, the main focus was to de ne a projection model and
camera pose extraction that could provide information in metric coordinates.
The second main objective was to adapt the CAMBADA localization algorithm
to work on the NAO robots, considering all the limitations it presents
when comparing to the MSL team, especially in terms of computational
resources.
A set of support tools were developed or improved in order to support the
test and development in both teams.
In general, the work developed during this thesis improved the performance
of the teams during play and also the e ectiveness of the developers team
when in development and test phases.Durante o desenvolvimento de software para robôs autónomos móveis, e
inevitavelmente necessário lidar com algum tipo de perceção. Al em disso,
ao lidar com agentes que possuem algum tipo de raciocínio para executar
as suas ações, há a necessidade de modelar o ambiente e o estado interno
do robô de forma a representar o cenário onde o robô opera.
Inserido no grupo ATRI, integrado na unidade de investigação IEETA da
Universidade de Aveiro, este trabalho usa dois dos projetos do grupo como
plataformas de teste, particularmente no cenário de futebol robótico com
robôs reais. Com o principal objetivo de desenvolver algoritmos para fusão
sensorial e de informação que possam ser usados eficazmente nestas equipas,
v arias abordagens de estado da arte foram estudadas, implementadas e
adaptadas para cada tipo de robôs.
No âmbito da equipa de RoboCup MSL, CAMBADA, o principal foco foi a
perceção da bola e obstáculos, com a criação de modelos capazes de providenciar
informação estendida para que o raciocino do robô possa ser cada
vez mais eficaz. Para o alcançar, v arias metodologias foram analisadas, implementadas,
comparadas e melhoradas.
Em relação a bola, foi efetuada uma análise de metodologias de filtragem
para estabilização da sua posição e estimação da sua velocidade. Tendo
o guarda-redes em mente, foi também realizado trabalho para providenciar
informação de bolas no ar.
Quanto aos obstáculos, foi criada uma nova definição para a forma como
são detetados pela visão e para o tipo de informação fornecida, bem como
uma metodologia para identificar quais dos obstáculos são colegas de equipa.
Além disso foi desenvolvido um algoritmo de rastreamento que, no final,
atribui um identicador único a cada obstáculo. Associado a melhoria na
perceção dos obstáculos foi criado um novo algoritmo para realizar desvio
reativo de obstáculos.
No contexto da equipa de RoboCup SPL, Portuguese Team, al em da inevitável adaptação de vários dos algoritmos j a desenvolvidos para fusão
sensorial e de informação, tendo em conta que foi recentemente criada, o
objetivo foi criar uma arquitetura sustentável de software que possa ser a
base para futuro desenvolvimento modular.
A arquitetura de software criada e baseada numa série de processos diferentes
e métodos de comunicação entre eles. Todos os processos foram
criados ou adaptados para a nova arquitetura e um conjunto base de papeis
e comportamentos foi definido para obter uma framework funcional base.
Em termos de perceção, o principal foco foi a definição de um modelo
de projeção e extração de pose da câmara que consiga providenciar informação em coordenadas métricas. O segundo objetivo principal era adaptar
o algoritmo de localização da CAMBADA para funcionar nos robôs NAO,
considerando todas as limitações apresentadas quando comparando com a
equipa MSL, principalmente em termos de recursos computacionais.
Um conjunto de ferramentas de suporte foram desenvolvidas ou melhoradas
para auxiliar o teste e desenvolvimento em ambas as equipas.
Em geral, o trabalho desenvolvido durante esta tese melhorou o desempenho
da equipas durante os jogos e também a eficácia da equipa de programação
durante as fases de desenvolvimento e teste
General Concepts for Human Supervision of Autonomous Robot Teams
For many dangerous, dirty or dull tasks like in search and rescue missions, deployment of autonomous teams of robots can be beneficial due to several reasons. First, robots can replace humans in the workspace. Second, autonomous robots reduce the workload of a human compared to teleoperated robots, and therefore multiple robots can in principle be supervised by a single human. Third, teams of robots allow distributed operation in time and space. This thesis investigates concepts of how to efficiently enable a human to supervise and support an autonomous robot team, as common concepts for teleoperation of robots do not apply because of the high mental workload. The goal is to find a way in between the two extremes of full autonomy and pure teleoperation, by allowing to adapt the robots’ level of autonomy to the current situation and the needs of the human supervisor. The methods presented in this thesis make use of the complementary strengths of humans and robots, by letting the robots do what they are good at, while the human should support the robots in situations that correspond to the human strengths.
To enable this type of collaboration between a human and a robot team, the human needs to have an adequate knowledge about the current state of the robots, the environment, and the mission. For this purpose, the concept of situation overview (SO) has been developed in this thesis, which is composed of the two components robot SO and mission SO. Robot SO includes information about the state and activities of each single robot in the team, while mission SO deals
with the progress of the mission and the cooperation between the robots. For obtaining SO a new event-based communication concept is presented in this thesis, that allows the robots to aggregate
information into discrete events using methods from complex event processing. The quality and quantity of the events that are actually sent to the supervisor can be adapted during runtime by defining positive and negative policies for (not) sending events that fulfill specific criteria. This reduces the required communication bandwidth compared to sending all available data.
Based on SO, the supervisor is enabled to efficiently interact with the robot team. Interactions can be initiated either by the human or by the robots. The developed concept for robot-initiated interactions is based on queries, that allow the robots to transfer decisions to another process or the supervisor. Various modes for answering the queries, ranging from fully autonomous to pure human decisions, allow to adapt the robots’ level of autonomy during runtime. Human-initiated interactions are limited to high-level commands, whereas interactions on the action level (e. g., teleoperation) are avoided, to account for the specific strengths of humans and robots. These commands can in principle be applied to quite general classes of task allocation methods for autonomous robot teams, e. g., in terms of specific restrictions, which are introduced into the system as constraints. In that way, the desired allocations emerge implicitly because of the introduced constraints, and the task allocation method does not need to be aware of the human supervisor in the loop. This method is applicable to different task allocation approaches, e. g.,
instantaneous or time-extended task assignments, and centralized or distributed algorithms.
The presented methods are evaluated by a number of different experiments with physical and simulated scenarios from urban search and rescue as well as robot soccer, and during robot competitions. The results show that with these methods a human supervisor can significantly improve the robot team performance
World Modeling for Intelligent Autonomous Systems
The functioning of intelligent autonomous systems requires constant situation awareness and cognition analysis. Thus, it needs a memory structure that contains a description of the surrounding environment (world model) and serves as a central information hub. This book presents a row of theoretical and experimental results in the field of world modeling. This includes areas of dynamic and prior knowledge modeling, information fusion, management and qualitative/quantitative information analysis
Collective cluster-based map merging in multi robot SLAM
New challenges arise with multi-robotics, while information integration is among the most important problems need to be solved in this field. For mobile robots, information integration usually refers to map merging . Map merging is the process of combining partial maps constructed by individual robots in order to build a global map of the environment.
Different approaches have been made toward solving map merging problem. Our method is based on transformational approach, in which the idea is to find regions of overlap between local maps and fuse them together using a set of transformations and similarity heuristic algorithms. The contribution of this work is an improvement made in the search space of candidate transformations. This was achieved by enforcing pair-wise partial localization technique over the local maps prior to any attempt to transform them. The experimental results show a noticeable improvement (15-20%) made in the overall mapping time using our technique
Marine Vessel Inspection as a Novel Field for Service Robotics: A Contribution to Systems, Control Methods and Semantic Perception Algorithms.
This cumulative thesis introduces a novel field for service robotics: the inspection of marine vessels using mobile inspection robots. In this thesis, three scientific contributions are provided and experimentally verified in the field of marine inspection, but are not limited to this type of application. The inspection scenario is merely a golden thread to combine the cumulative scientific results presented in this thesis. The first contribution is an adaptive, proprioceptive control approach for hybrid leg-wheel robots, such as the robot ASGUARD described in this thesis. The robot is able to deal with rough terrain and stairs, due to the control concept introduced in this thesis. The proposed system is a suitable platform to move inside the cargo holds of bulk carriers and to deliver visual data from inside the hold. Additionally, the proposed system also has stair climbing abilities, allowing the system to move between different decks. The robot adapts its gait pattern dynamically based on proprioceptive data received from the joint motors and based on the pitch and tilt angle of the robot's body during locomotion. The second major contribution of the thesis is an independent ship inspection system, consisting of a magnetic wall climbing robot for bulkhead inspection, a particle filter based localization method, and a spatial content management system (SCMS) for spatial inspection data representation and organization. The system described in this work was evaluated in several laboratory experiments and field trials on two different marine vessels in close collaboration with ship surveyors. The third scientific contribution of the thesis is a novel approach to structural classification using semantic perception approaches. By these methods, a structured environment can be semantically annotated, based on the spatial relationships between spatial entities and spatial features. This method was verified in the domain of indoor perception (logistics and household environment), for soil sample classification, and for the classification of the structural parts of a marine vessel. The proposed method allows the description of the structural parts of a cargo hold in order to localize the inspection robot or any detected damage. The algorithms proposed in this thesis are based on unorganized 3D point clouds, generated by a LIDAR within a ship's cargo hold. Two different semantic perception methods are proposed in this thesis. One approach is based on probabilistic constraint networks; the second approach is based on Fuzzy Description Logic and spatial reasoning using a spatial ontology about the environment