A pesquisa na área de robótica espacial lida com problemas exclusivos, acarretados pela natureza e características dinâmicas dos sistemas. Isso torna a modelagem uma área de extrema importância para garantir um desempenho satisfatório. A maior característica dos braços robóticos espaciais é que seu movimento perturba a espaçonave na qual está acoplado. Essa propriedade deve ser levada em consideração, especialmente no caso de robôs de base livre flutuante que não possuem controle de posição ou atitude na base. A maior destreza e flexibilidade de manipuladores de múltiplos braços faz com que sua pesquisa seja colocada em foco. Eles possuem maior possibilidade de lidar com cargas maiores e fornecer maior acurácia em tarefas como montagens, reparos, abastecimento, etc. Nesse contexto, o presente trabalho tem como objetivo o desenvolvimento do modelo de um manipulador espacial de base livre flutuante de dois braços. Esse modelo, então, foi aplicado no desenvolvimento de um sistema de controle. A metodologia sugerida facilita, não só a obtenção do modelo, como também a especificação de controladores. Dois esquemas de controle foram desenvolvidos: um no espaço da tarefa e outro no espaço das juntas, com diferentes especificações de trajetórias. A simulação do sistema foi realizada no ambiente Simulink (MATLAB) e os resultados são discutidos, indicando as situações de falha dos controladores especificados. / Space robotics research faces unique problems, which are mainly related to the intrinsic nature and dynamic characteristics of its systems. As a consequence, modelling becomes essential to guarantee the best system result. A important characteristic of space robotic arms is that their movements affect their bases position and attitude. This property must be taken into account, specially in the case of free floating space manipulators which have no control system for the base. High dexterity and flexibility of multi-arm manipulators cause their research to be a focus for the community. With higher loads and accuracy demands, they are more likely to suceed in tasks such as maintenance, assembly, refueling, among others. In that context, this thesis aims to develop a model for a dual-arm free-floating space manipulator. The model, then, is used in the design of a control system. The suggested methodology makes the process easier not only the modelling, but also the controller design. Two control schemes were developed: one in joint and the other in task space, with different trajectories. System simulations were run on Simulink (MATLAB) and the obtained results were discussed, with comments regarding fault situations for the specified control systems.

A pesquisa na área de robótica espacial lida com problemas exclusivos, acarretados pela natureza e características dinâmicas dos sistemas. Isso torna a modelagem uma área de extrema importância para garantir um desempenho satisfatório. A maior característica dos braços robóticos espaciais é que seu movimento perturba a espaçonave na qual está acoplado. Essa propriedade deve ser levada em consideração, especialmente no caso de robôs de base livre flutuante que não possuem controle de posição ou atitude na base. A maior destreza e flexibilidade de manipuladores de múltiplos braços faz com que sua pesquisa seja colocada em foco. Eles possuem maior possibilidade de lidar com cargas maiores e fornecer maior acurácia em tarefas como montagens, reparos, abastecimento, etc. Nesse contexto, o presente trabalho tem como objetivo o desenvolvimento do modelo de um manipulador espacial de base livre flutuante de dois braços. Esse modelo, então, foi aplicado no desenvolvimento de um sistema de controle. A metodologia sugerida facilita, não só a obtenção do modelo, como também a especificação de controladores. Dois esquemas de controle foram desenvolvidos: um no espaço da tarefa e outro no espaço das juntas, com diferentes especificações de trajetórias. A simulação do sistema foi realizada no ambiente Simulink (MATLAB) e os resultados são discutidos, indicando as situações de falha dos controladores especificados. / Space robotics research faces unique problems, which are mainly related to the intrinsic nature and dynamic characteristics of its systems. As a consequence, modelling becomes essential to guarantee the best system result. A important characteristic of space robotic arms is that their movements affect their bases position and attitude. This property must be taken into account, specially in the case of free floating space manipulators which have no control system for the base. High dexterity and flexibility of multi-arm manipulators cause their research to be a focus for the community. With higher loads and accuracy demands, they are more likely to suceed in tasks such as maintenance, assembly, refueling, among others. In that context, this thesis aims to develop a model for a dual-arm free-floating space manipulator. The model, then, is used in the design of a control system. The suggested methodology makes the process easier not only the modelling, but also the controller design. Two control schemes were developed: one in joint and the other in task space, with different trajectories. System simulations were run on Simulink (MATLAB) and the obtained results were discussed, with comments regarding fault situations for the specified control systems.

Dans cette thèse, un stabilisateur actif est conçu pour être embarqué sur la plate-forme d'un Robot Parallèle à Câbles (RPC) et compenser les vibrations de la plate-forme en produisant un torseur d’effort sur celle-ci. Tout d’abord, une modélisation mécanique de divers dispositifs de stabilisation actifs permet de choisir une solution appropriée à la compensation des vibrations. La solution sélectionnée consiste en un stabilisateur composé de bras en rotation. Ensuite, ce modèle est utilisé pour optimiser la structure du stabilisateur en recherchant quelle disposition de ses bras permet de maximiser la puissance fournie par le stabilisateur à la plate-forme mobile du RPC.Une stratégie de commande est alors proposée pour contrôler le système composé de la plate-forme mobile du RPC et du stabilisateur actif embarqué. Ce système étant constitué de deux parties fonctionnant à des échelles de temps différentes, la théorie de la perturbation singulière est utilisée pour prouver la stabilité de la commande proposée.Enfin, des expériences en simulation permettent de valider l’utilisation d’un stabilisateur actif embarqué pour la compensation des vibrations de la plate-forme mobile d’un RPC et commandé avec la loi de commande proposée dans cette thèse. / In this thesis, an active stabilizer is designed to be embedded on the platform of a Cable-Driven Parallel Robot (CDPR) and to damp vibrations affecting the platform by producing a wrench on it.First, a mechanical modeling of various active stabilization devices allows the choice of an appropriate solution for vibration damping. The selected solution consists of a stabilizer composed of rotating arms. Then, this model is used to optimize the stabilizer structure by looking at which arm arrangement maximizes the power delivered by the stabilizer to the CDPR mobile platform.A control strategy is then proposed for the system consisting of the CDPR mobile platform and the embedded active stabilizer. As this system consists of two parts operating at different time scales, the singular perturbation theory is used to prove the stability of the proposed control.Finally, simulation experiments make it possible to validate the use of an on-board active stabilizer to damp the vibrations of the mobile platform of a CDPR, and controlled with the control law proposed in this thesis.

A Robótica tem avançando significativamente nas últimas décadas, chegando a apresentar produtos comerciais, como robôs aspiradores de pó e quadricópteros. Com a integração cada vez maior de robôs em nossa sociedade, mostra-se necessário o desenvolvimento de métodos de interação entre pessoas e robôs para gerenciar o convívio e trabalho mútuo. Existem alguns trabalhos na literatura que consideram o posicionamento socialmente aceitável de um robô, acompanhando um indivíduo, mas não consideram o caso de uma equipe de robôs navegando com uma pessoa considerando aspectos de proxêmica. Nesta tese, são propostas várias estratégias de acompanhamento de um humano por um time de robôs social, que são bioinspiradas por serem baseadas em técnicas de inteligencia coletiva e comportamento social. Experimentos simulados são apresentados visando comparar as técnicas propostas em diversos cenários, destacando-se as vantagens e desvantagens de cada uma delas. Experimentos reais permitiram uma análise da percepção das pessoas em interagir com um ou mais robôs, demonstrando que nenhuma diferença na impressão dos indivíduos foi encontrada. / The field of Robotics have been advancing significantly on the last few decades, presenting commercial products like vacuum cleaning robots and autonomous quadcopter drones. With the increasing presence of robots in our routine, it is necessary to develop human-robot interaction schemes to manage their relationship. Works that deal with a single robot doing a socially acceptable human following behavior are available, but do not consider cases where a robot team walks with a human In this thesis, it is presented a solution for social navigation between a human and a robot team combining socially aware human following techniques with a multirobot escorting method, generating four bioinspired navigation strategies based on collective intelligence and social behavior. Experiments comparing these four strategies on a simulated environment in various scenarios highlighted advantages and disadvantages of each strategy. Moreover, an experiment with real robots was made to investigate the difference on perception of people when interacting with one or three robots, and no difference was found.

Cette thèse aborde la problématique du robot assistant et plus particulièrement les aspects décisionnels qui y sont liés. Un robot assistant est amené à interargir avec des hommes ce qui impose qu'il doit intègrer dans son processus décisionnel de haut-niveau les contraintes sociales inhérentes à un comportement acceptable par son(ses) partenaire(s) humain(s). Cette thèse propose une approche permettant de décrire de manière générique diverses règles sociales qui sont introduites dans le processus de planification du robot afin d'évaluer la qualité sociale des plans solutions et de ne retenir que le(s) plus approprié(s). Cette thèse décrit également l'implémentation de cette approche sous la forme d'un planificateur de tâches appelé HATP (Human Aware Task Planner en anglais). Enfin, cette thèse propose une validation de l'approche développée grâce à un scénario de simulation et à une mise en oeuvre sur un robot réel.

<p>Automation in manufacturing has come far by using industrial robots. However, industrial robots require tremendous efforts in static calibration due to their lack of senses. Force and vision are the most useful sensing capabilities for a robot system operating in an unknown or uncalibrated environment [4]and by integrating sensors in real-time with industrial robot controllers, dynamic processes need far less calibration which leads to reduced lead time. By using robot systems which are more dynamic and can perform complex tasks with simple instructions, the production efficiency will rise and hence also the profit for companies using them. </p><p>Although much research has been presented within the research community, current industrial robot systems have very limited support for external sensor feedback, and the state-of-the-art robots today have generally no feedback loop that can handle external force- or position controlled feedback. Where it exists, feedback at the rate of 10 Hz is considered to berare and is far from real-time control. </p><p>A new system where the feedback control can be possible within a real-time behavior, developed at Lund Institute of Technology, has been implemented and deployed at Linköping Institute of Technology. </p><p>The new system for rapid feedback control is a highly complex system, possible to install in existing robot cells, and enables real-time (250 Hz) sensor feedback to the robot controller. However, the system is not yet fully developed, and a lot of issues need to be considered before it can reach the market in other than specific applications. </p><p>The implementation and deployment of the new interface at LiTH shows that the potential for this system is large, since it makes production with robots exceedingly flexible and dynamic, and the fact that the system works with real- time feedback makes industrial robots more useful in tasks for manufacturing.</p>

This thesis explores the design and evaluation of human-robot communication for service robots that use natural language to interact with people.  The research is centred around three themes: design of human-robot communication; evaluation of miscommunication in human-robot communication; and the analysis of spatial influence as empiric phenomenon and design element.  The method has been to put users in situations of future use through means of Hi-fi simulation. Several scenarios were enacted using the Wizard-of-Oz technique: a robot intended for fetch- and carry services in an office environment; and a robot acting in what can be characterised as a home tour, where the user teaches objects and locations to the robot. Using these scenarios a corpus of human-robot communication was developed and analysed.  The analysis of the communicative behaviours led to the following observations: the users communicate with the robot in order to solve a main task goal. In order to fulfil this goal they overtake service actions that the robot is incapable of. Once users have understood that the robot is capable of performing actions, they explore its capabilities.  During the interactions the users continuously monitor the behaviour of the robot, attempting to elicit feedback or to draw its perceptual attention to the users’ communicative behaviour. Information related to the communicative status of the robot seems to have a fundamental impact on the quality of interaction. Large portions of the miscommunication that occurs in the analysed scenarios can be attributed to ill-timed, lacking or irrelevant feedback from the robot.  The analysis of the corpus data also showed that the users’ spatial behaviour seemed to be influenced by the robot’s communicative behaviour, embodiment and positioning. This means that we in robot design can consider the use strategies for spatial prompting to influence the users’ spatial behaviour.  The understanding of the importance of continuously providing information of the communicative status of the robot to it’s users leaves us with an intriguing design challenge for the future: When designing communication for a service robot we need to design communication for the robot work tasks; and simultaneously, provide information based on the systems communicative status to continuously make users aware of the robots communicative capability. / QC 20100714

In this thesis we present a hybrid control methodology using Artificial Potential Fields (APF) integrated with a modified Simulated Annealing (SA) optimization algorithm for motion planning of a multi-link robots team. The principle of this work is based on the locomotion of a snake where subsequent links follow the trace of the head. The proposed algorithm uses the APF method which provides simple, efficient and effective path planning and the modified SA is applied in order for the robots to recover from a local minima. Modifications to the SA algorithm improve the performance of the algorithm and reduce convergence time. Validation on a three-link snake robot shows that the derived control laws from the motion planning algorithm that combine APF and SA can successfully navigate the robot to reach its destination, while avoiding collisions with multiple obstacles and other robots in its path as well as recover from local minima. To improve the performance of the algorithm, the gradient descent method is replaced by Newton’s method which helps in reducing the zigzagging phenomenon in gradient descent method while the robot moves in the vicinity of an obstacle. / UOIT

Controlling systems with multiple robots is quickly becoming the next large hurdle that must be overcome for groups of robots to successfully function as a team. An agent oriented approach for this problem is presented in this thesis. By using an agent oriented method, the robots can act independently yet still work together. To be able to establish communities of robots, a basic agent oriented control system for each robot must first be implemented. This thesis introduces a novel method to create Physical Robot Agents, promoting a separation of cognitive and reactive behaviours into a two layer system. These layers are further abstracted into key subsections that are required for the Physical Robot Agents to function. To test this architecture, experiments are performed with physical robots to determine the feasibility of this approach. <br /><br /> A real-time implementation of a Physical Robot Agent would greatly expand its field of use. The speed of internal communication is analyzed to validate the application of this architecture to real-time tasks. <br /><br /> It is concluded that the Physical Robot Agents are well suited for multiple robot systems and that real-time applications are feasible.

Teams of mobile robots have numerous applications, such as space exploration, underground mining, warehousing, and building security. Multi-robot teams can provide a number of practical benefits in such applications, including simultaneous presence in multiple locations, improved system performance, and greater robustness and redundancy compared to individual robots. This thesis addresses three aspects of coordination and navigation for teams of mobile robots: localization, the estimation of the position of each robot in the environment; motion planning, the process of finding collision-free trajectories through the environment; and task allocation, the selection of appropriate goals to be assigned to each robot. Each of these topics are investigated in the context of many robots working in a common environment. A particle-filter based system for cooperative global localization is presented. The system combines the sensor data from three robots, including measurements of the distances between robots, to cooperatively estimate the global position of each robot in the environment. The method is developed for a single triad of robots, then extended to larger groups of robots. The algorithm is demonstrated in a simulation of robots equipped with only simple range sensors, and is shown to successfully achieve global localization of robots that are unable to localize using only their own local sensor data. Motion planning is investigated for large teams of robots operating in tunnel and corridor environments, where coordinated planning is often required to avoid collision or deadlock conditions. A complete and scalable motion planning algorithm is presented and evaluated in simulation with up to 150 robots. In contrast to popular decoupled approaches to motion planning (which cannot guarantee a solution), this algorithm uses a multi-phase approach to create and maintain obstacle-free paths through a graph representation of the environment. The resulting plan is a set of collision-free trajectories, guaranteeing that every robot will reach its goal. The problem of task allocation is considered in the same type of tunnel and corridor environments, where tasks are defined as locations in the environment that must be visited by one of the robots in the team. To find efficient solutions to the task allocation problem, an optimization approach is used to generate potential task assignments, and select the best solution. The multi-phase motion planner is applied within this system as an efficient method of evaluating potential task assignments for many robots in a large environment. The algorithm is evaluated in simulations with up to 20 robots in a map of large underground mine. A real-world implementation of 3 physical robots was used to demonstrate the implementation of the multi-phase motion planning and task allocation systems. A centralized motion planning and task allocation system was developed, incorporating localization and time-dependent trajectory tracking on the robot processors, enabling cooperative navigation in a shared hallway environment.