15 research outputs found
Cooperative coevolution of morphologically heterogeneous robots
Morphologically heterogeneous multirobot teams have
shown significant potential in many applications. While cooperative coevolutionary algorithms can be used for synthesising controllers for heterogeneous multirobot systems, they
have been almost exclusively applied to morphologically homogeneous systems. In this paper, we investigate if and
how cooperative coevolutionary algorithms can be used to
evolve behavioural control for a morphologically heterogeneous multirobot system. Our experiments rely on a simulated task, where a ground robot with a simple sensor-actuator
configuration must cooperate tightly with a more complex
aerial robot to find and collect items in the environment. We
first show how differences in the number and complexity of
skills each robot has to learn can impair the effectiveness of
cooperative coevolution. We then show how coevolutionâs
effectiveness can be improved using incremental evolution or
novelty-driven coevolution. Despite its limitations, we show
that coevolution is a viable approach for synthesising control
for morphologically heterogeneous systems.info:eu-repo/semantics/publishedVersio
A Survey and Analysis of Cooperative Multi-Agent Robot Systems: Challenges and Directions
Research in the area of cooperative multi-agent robot systems has received wide attention among researchers in recent years. The main concern is to find the effective coordination among autonomous agents to perform the task in order to achieve a high quality of overall performance. Therefore, this paper reviewed various selected literatures primarily from recent conference proceedings and journals related to cooperation and coordination of multi-agent robot systems (MARS). The problems, issues, and directions of MARS research have been investigated in the literature reviews. Three main elements of MARS which are the type of agents, control architectures, and communications were discussed thoroughly in the beginning of this paper. A series of problems together with the issues were analyzed and reviewed, which included centralized and decentralized control, consensus, containment, formation, task allocation, intelligences, optimization and communications of multi-agent robots. Since the research in the field of multi-agent robot research is expanding, some issues and future challenges in MARS are recalled, discussed and clarified with future directions. Finally, the paper is concluded with some recommendations with respect to multi-agent systems
FODEFU : formaciones defensivas para fĂștbol robĂłtico
En los sistemas multiagentes se necesita que los agentes tengan dos caracterĂsticas, que actĂșen de manera autĂłnoma y de manera cooperativa para cumplir las metas del sistema. En este documento se presenta una nueva implementaciĂłn para el caso de estudio del equipo de fĂștbol robĂłtico Bochica de la Pontificia universidad Javeriana. En esta implementaciĂłn se encuentran diseñadas nuevas formaciones defensivas con el fin de mejorar el orden y la estructura de juego del equipo y tambiĂ©n nuevos roles para los agentes con el fin de mejorar la autonomĂa y la toma de decisiones por parte de los agentes en diferentes situaciones de juego.Ingeniero (a) de SistemasPregrad
Decentralized Autonomous Navigation Strategies for Multi-Robot Search and Rescue
In this report, we try to improve the performance of existing approaches for
search operations in multi-robot context. We propose three novel algorithms
that are using a triangular grid pattern, i.e., robots certainly go through the
vertices of a triangular grid during the search procedure. The main advantage
of using a triangular grid pattern is that it is asymptotically optimal in
terms of the minimum number of robots required for the complete coverage of an
arbitrary bounded area. We use a new topological map which is made and shared
by robots during the search operation. We consider an area that is unknown to
the robots a priori with an arbitrary shape, containing some obstacles. Unlike
many current heuristic algorithms, we give mathematically proofs of convergence
of the algorithms. The computer simulation results for the proposed algorithms
are presented using a simulator of real robots and environment. We evaluate the
performance of the algorithms via experiments with real robots. We compare the
performance of our own algorithms with three existing algorithms from other
researchers. The results demonstrate the merits of our proposed solution. A
further study on formation building with obstacle avoidance for a team of
mobile robots is presented in this report. We propose a decentralized formation
building with obstacle avoidance algorithm for a group of mobile robots to move
in a defined geometric configuration. Furthermore, we consider a more
complicated formation problem with a group of anonymous robots; these robots
are not aware of their position in the final configuration and need to reach a
consensus during the formation process. We propose a randomized algorithm for
the anonymous robots that achieves the convergence to a desired configuration
with probability 1. We also propose a novel obstacle avoidance rule, used in
the formation building algorithm.Comment: arXiv admin note: substantial text overlap with arXiv:1402.5188 by
other author
Behavior Classification, Security, and Consensus in Societies of Robots
This thesis addresses some fundamental issues toward the realization of "societies" of robots. This objective requires dealing with large numbers of heterogenous autonomous systems, differing in their bodies, sensing and intelligence, that are made to coexist, communicate, learn and classify, and compete fairly, while achieving their individual goals.
First, as in human or animal societies, robots must be able to perform cooperative "behaviors" that involve coordination of their actions, based on their own goals, proprioceptive sensing, and information they can receive from other neighboring robots. An effective way to successfully achieve cooperation is obtained by requiring that robots share a set of decentralized motion "rules" involving only locally available data. A first contribution of the thesis consists in showing how these behaviors can be nicely described by a suitable hybrid formalism, including the heterogenous dynamics of every robots and the above mentioned rules that are based on events.
A second contribution deals with the problem of classifying a set of robotic agents, based on their dynamics or the interaction protocols they obeys, as belonging to different "species". Various procedures are proposed allowing the construction of a distributed classification system, based on a decentralized identification mechanism, by which every agent classifies its neighbors using only locally available information. By using this mechanism, members of the society can reach a consensus on the environment and on the integrity of the other neighboring robots, so as to improve the overall security of the society. This objective involves the study of convergence of information that is not represented by real numbers, as often in the literature, rather by sets. The dynamics of the evolution of information across a number of robots is described by set-valued iterative maps. While the study of convergence of set-valued iterative maps is highly complex in general, this thesis focuses on Boolean maps, which are comprised of arbitrary combinations of unions, intersections, and complements of sets.
Through the development of an industrial robotic society, it is finally shown how the proposed technique applies to a real and commercially relevant case-study. This society sets the basis for a full-fledged factory of the future, where the different and heterogeneous agents operate and interact using a blend of autonomous skills, social rules, and central coordination
A Complexity-Based Approach to Intra-Organizational Team Selection
Early studies recognized the significance of team's work capacity and suggested the selection of team members based on individual skills and performance in alignment with task characteristics. The equitable team selection method, for example, assigns people to different tasks with even skill distributions for the best overall performance. Recent advancement in organization science also identifies the importance of contextual skills. However, work teams are complex adaptive systems with interdependence between workers and social environment, and exhibit surprising, nonlinear behavior. Optimizing individual stages without taking organizational complexity into account is unlikely to yield a high performing new combination of teams. The objectives of this study can be stated as: a) Utilizing complex system theory to better understand the processes of team selection including forming teams with considering worker's interdependence and replacing the unsuitable members through a time frame; b) Comparing different team selection methods, including random selection, equity method, using knowledge of interdependence in different economic conditions through simulation; c) Comparing different policies of replacing members of teams. This study utilizes a computational model to understand the complexity of project team selection and to examine how diversity of capability and interdependence between workers to effect team performance in different economic conditions. The NK model, a widely used theory for complex systems is utilized here to illustrate the worker's interdependence and fed into an Agent-Based Model. This study uses a small design firm as a case implementation to examine the performance of a variety of team selection approaches and replacement policies. Project data, task assignment, and individual and team performance information were collected for the period of 2009-2011. The simulation results show that while the equity selection method can increase the diversity of capabilities of teams, the net performance is often worse than optimizing worker interdependencies. This study suggests that managers should protect their higher-performing workers with minimal interdependence disruption when they considered team selection. Thus taking the advantages and disadvantages of all three policies into account, transferring low contributors or least supported members are recommended to be enacted before hiring new workers to avoid this last policy's especially large additional costs
Trajectory solutions for a game-playing robot using nonprehensile manipulation methods and machine vision
The need for autonomous systems designed to play games, both strategy-based and
physical, comes from the quest to model human behaviour under tough and
competitive environments that require human skill at its best. In the last two decades,
and especially after the 1996 defeat of the world chess champion by a chess-playing
computer, physical games have been receiving greater attention. Robocup TM, i.e.
robotic football, is a well-known example, with the participation of thousands of
researchers all over the world. The robots created to play snooker/pool/billiards are
placed in this context. Snooker, as well as being a game of strategy, also requires
accurate physical manipulation skills from the player, and these two aspects qualify
snooker as a potential game for autonomous system development research. Although
research into playing strategy in snooker has made considerable progress using
various artificial intelligence methods, the physical manipulation part of the game is
not fully addressed by the robots created so far. This thesis looks at the different ball
manipulation options snooker players use, like the shots that impart spin to the ball in
order to accurately position the balls on the table, by trying to predict the ball
trajectories under the action of various dynamic phenomena, such as impacts.
A 3-degree of freedom robot, which can manipulate the snooker cue on a par with
humans, at high velocities, using a servomotor, and position the snooker cue on the
ball accurately with the help of a stepper drive, is designed and fabricated. [Continues.
SystÚme autonome de sécurité lors de la préparation d'un repas pour des personnes cognitivement déficientes dans un habitat intelligent pour la santé
Dans les pays dĂ©veloppĂ©s tels que le Canada ou la France, la population est vieillissante et le nombre de personnes atteintes de dĂ©ficiences cognitives augmente en consĂ©quence. Ces troubles ont des consĂ©quences sur les activitĂ©s de la vie quotidienne pour les personnes qui en souffrent. Selon lâautonomie de ces personnes et la sĂ©vĂ©ritĂ© de leur dĂ©ficience, un hĂ©bergement en centre spĂ©cialisĂ© peut ĂȘtre envisagĂ©. Ces centres spĂ©cialisĂ©s reprĂ©sentent souvent un coĂ»t financier Ă©norme tant pour la personne que pour la sociĂ©tĂ©. Afin de limiter ces coĂ»ts, une solution alternative a Ă©mergĂ© : les habitats domotiques. Ce sont des habitats dans lesquels un ensemble de technologies permet de pallier aux dĂ©ficiences des personnes et de leur donner une autonomie accrue. Pour ces personnes, certaines de ces activitĂ©s de la vie quotidienne peuvent reprĂ©senter des obstacles voire ĂȘtre dangereuses. Par exemple, lâactivitĂ© de prĂ©paration dâun repas est une activitĂ© complexe qui peut prĂ©senter des risques variĂ©s pour des personnes atteintes de dĂ©ficiences. Ces personnes sont alors assistĂ©es par des professionnels ou leurs aidants naturels lors de cette activitĂ© et peuvent perdre lâenvie de prĂ©parer Ă manger. Lâobjectif de cette thĂšse est de concevoir un systĂšme permettant Ă ces personnes de rĂ©aliser lâactivitĂ© de la prĂ©paration dâun repas en toute autonomie et en toute sĂ©curitĂ©. Dâune part, on retrouve la personne atteinte, qui selon sa dĂ©ficience, aura une façon unique pour rĂ©aliser cette activitĂ©. Ces personnes vivent rarement seules, il faut tenir compte quâun public variĂ© puisse bĂ©nĂ©ficier du systĂšme pour la prĂ©paration dâun repas. Dâautre part, cette activitĂ© aura lieu dans un environnement diffĂ©rent pour chaque habitat. Le systĂšme doit assurer la sĂ©curitĂ© lors de lâactivitĂ© de prĂ©paration de repas, par consĂ©quent, la fiabilitĂ© du systĂšme est un critĂšre important. Ces habitats sont gĂ©nĂ©ralement dĂ©jĂ Ă©quipĂ©s dâappareils, il devient nĂ©cessaire pour le systĂšme de pouvoir sâadapter Ă ces appareils existants. Lâobjectif de ces travaux est la rĂ©alisation dâun prototype permettant dâassurer la sĂ©curitĂ© lors de lâactivitĂ© de la prĂ©paration dâun repas par des personnes atteintes de la maladie dâAlzheimer et ses aidants (professionnels ou naturels). Ce prototype doit sâadapter aux besoins des usagers, de son environnement et du matĂ©riel sur lequel il est dĂ©ployĂ©.
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Pour ce faire, le systĂšme, basĂ© sur un systĂšme multi-agents, applique des rĂšgles de sĂ©curitĂ© qui se personnalisent par le biais du profil mĂ©dical des usagers. La rĂ©alisation de modĂšles pour chaque objectif a permis de rĂ©aliser une architecture dâun systĂšme flexible. Ces modĂšles ont Ă©tĂ© dĂ©ployĂ©s sur deux applications distinctes. Nos travaux ont Ă©tĂ© menĂ©s au sein de deux laboratoires, qui chacun, disposent dâappareils de cuisine diffĂ©rents dans leurs habitats intelligents pour la santĂ©. Les besoins en termes de capteurs et leur interfaçage avec le systĂšme sont prĂ©sentĂ©s. Enfin, le systĂšme a pu ĂȘtre testĂ© dans ces deux environnements, son adaptation vis-Ă -vis dâune clientĂšle variĂ©e et pour plusieurs risques de sĂ©curitĂ© Ă travers des scĂ©narios dâusage. Les rĂ©sultats de ces expĂ©rimentations ont Ă©tĂ© concluants et ont permis de montrer que le prototype rĂ©pond bien aux objectifs visĂ©s