Redundant robotic systems, in terms of manipulators with one or twoarms, mobile manipulators, and multi-agent systems, have received an in-creasing amount of attention in recent years. In this thesis we describe severalways to improve robotic system performance by exploiting the redundancy. As the robot workspace becomes increasingly dynamic, it is common towork with imperfect geometric models of the robots or its workspace. Inorder to control the robot in a robust way in the presence of geometric uncer-tainties, we propose to assess the stability of our controller with respect to acertain task by deriving bounds on the geometric uncertainties. Preliminaryexperimental results support the fact that stability is ensured if the proposedbounds on the geometric uncertainties are fulfilled. As a non-contact measurement, computer vision could provide rich infor-mation for robot control. We introduce a two step method that transformsthe position-based visual servoing problem into a quadratic optimization prob-lem with linear constraints. This method is optimal in terms of minimizinggeodesic distance and allows us to integrate constraints, e.g. visibility con-straints, in a natural way. In the case of a single robot with redundant degrees of freedom, we canspecify a family of complex robotic tasks using constraint based programming(CBP). CBP allows us to represent robotic tasks with a set of equality andinequality constraints. Using these constraints we can formulate quadraticprogramming problems that exploit the redundancy of the robot and itera-tively resolve the trade-off between the different constraints. For example, wecould improve the velocity or force transmission ratios along a task-dependent direction using the priorities between different constraints in real time. Using the reactiveness of CBP, we formulated and implemented a dual-armpan cleaning task. If we mount a dual-arm robot on a mobile base, we proposeto use a virtual kinematic chain to specify the coordination between the mobilebase and two arms. Using the modularity of the CBP, we can integrate themobility and dual-arm manipulation by adding coordination constraints intoan optimization problem where dual-arm manipulation constraints are alreadyspecified. We also found that the reactiveness and modularity of the CBPapproach is important in the context of teleoperation. Inspired by the 3Ddesign community, we proposed a teleoperation interface control mode thatis identical to the ones being used to locally navigate the virtual viewpoint ofmost Computer Aided Design (CAD) softwares. In the case of multiple robots, we combine ideas from multi-agent coopera-tive coverage control, with problem formulations from the resource allocationfield, to create a distributed convergent approach to the resource positioningproblem. / <p>QC 20160224</p>

Synchronizing hand and foot movements under reactive versus predictive control results in differential timing structures between the responses. Under reactive control, where the movement is externally triggered, the electromyographic (EMG) responses are synchronized, resulting in the hand displacement preceding the foot. Under predictive control, where the movement is self-paced, the motor commands are organized such that the displacement onset occurs relatively synchronously, requiring the EMG onset of the foot to precede that of the hand. The current study used a startling acoustic stimulus (SAS), which is known to involuntarily trigger a prepared response, to investigate whether these results are due to differences in the pre-programmed timing initiation structure of the responses. Participants (n=17) performed isolated and synchronous movements of the right heel and right hand under both reactive and predictive modes of control. The reactive condition involved a simple reaction time (RT) task where participants performed the required movement in response to a visual go-signal. The predictive condition involved an anticipation-timing task where participants initiated the required movement coincidently with a sweeping clock hand reaching a target. On a subset of trials, a SAS (114 dB) was presented 150 ms prior to the imperative stimulus. Results from the SAS trials revealed that while the differential timing structures between the responses was maintained under both reactive and predictive control, the EMG onset asynchrony under predictive control was significantly smaller following the SAS. Additionally, there was no difference in the effect of the SAS when the movements were performed in isolation versus synchronously. Together, these results suggest that the timing between the responses, which differs between the two control modes, is pre-programmed; however, under predictive control, an increase in cortical activation from the SAS may have shortened the between-limb delay.

La déformation de torsion que subit un profil aérodynamique a une importance capitale car elle a une influence directe sur la valeur des incidences locales et donc sur la valeur locale des densités de portance et de traînée. L'amélioration des performances aérodynamiques passe donc par la connaissance et la maîtrise de ce vrillage. Cette thèse se propose d'y contribuer. Une des méthodes développées actuellement par de nombreux auteurs consiste à munir le profil d'actionneurs permettant de le déformer en torsion de manière à compenser tout ou partie, voire même contrer, la déformation « naturelle » de la structure. Cette méthode, dite de contrôle actif, est certes très efficace, mais elle présente des limitations car elle nécessite l'introduction d'une quantité d'énergie qui peut être importante. La méthode que nous proposons ici pour maîtriser le vrillage du profil consiste à modifier ses conditions d'équilibre interne. En solidarisant ou en désolidarisant des cloisons à l'intérieur du profil, il est possible de déplacer le centre de torsion des sections du profil sans modifier sa forme extérieure. Ces modifications internes induisent donc une modulation du moment de torsion et donc une modulation du vrillage. Ce processus ne demande que très peu d'énergie. A partir d'un profil simple, des simulations ont permis de montrer le potentiel théorique du système proposé. Trois démonstrateurs, de complexité croissante, ont également été réalisés pour évaluer les capacités du contrôle « réactif » de la torsion. La technique a été validée par la deuxième démonstration. Malheureusement, le troisième démonstrateur, beaucoup plus complexe, n'a pas permis, à l’heure actuelle, d'obtenir la validation finale. / The torsional deformation of aerodynamic profiles has to be considered with care because it induces a change in the angle of attack and therefore changes in the local densities of lift and drag forces. The improvement of the aerodynamic performances does require a good knowledge and control of the twist of the airfoil. A method currently developed by a lot of authors consists in inserting in the airfoil some actuators whose action tends to increase or reduce the ‘natural’ deformation of the structure. This method, named active control, is very effective but it has some limitations because it needs a level of energy which can be high. The method we propose to control the twist of the airfoil consists in modifying the internal elastic equilibrium of the structure. By joining or disjoining some walls inside the profile, it is possible to shift the shear center of the profile without any change of its external shape. So, these internal modifications induce variations of the torsional moment and therefore a variation of the twist angle. The process is no energy consuming. By means of a simple profile, simulations have been performed to show the theoretical potential of the proposed system. Three demonstrators have also been designed with increasing complexity to evaluate the feasibility of the ‘reactive’ control of the twist. The technique has been validated by the second demonstrator. Unfortunately, the third demonstrator, much more complex, has not shown the final demonstration.

In autonomous navigation of mobile robots the dynamic environment is a source of problems. Because it is not possible to model all the possible conditions, the key point in the robot control is to design a system that is adaptable to different conditions and robust in dynamic environments. This study presents a reactive control system for a Khepera robot with the ability to navigate in a dynamic environment for reaching goal objects. The main motivation of this research is to design a robot control, which is robust to sensor errors and sudden changes and adaptable to different environments and conditions. Behavior based approach is used with taking the advantage of fuzzy reasoning in design. Experiments are made on Webots, which is a simulation environment for Khepera robot.

Deciding to use lethal force with a firearm is a critical decision that has major implications within society. In order to investigate racial bias in shooting decisions, the current dissertation uses the First-Person Shooter Task (FPST). Previous literature has shown that shooting decisions in this task are made faster and more often towards Black targets when compared to White targets. The relationship between this shooting bias and individual differences in cognitive ability is explored. The FPST was presented in three different conditions, each with trial proportions that varied in level of stereotype congruency (i.e., trials that are congruent with racial stereotypes). A Baseline condition presented an even distribution of Black Armed, Black Unarmed, White Armed, and White unarmed targets. A Mostly Congruent condition presented most (80%) of the Black targets as armed and most (80%) of the White targets as unarmed. A Mostly Incongruent condition presented most of the Black targets as unarmed and the White targets as mostly armed. Working memory, theoretically represented as a system of three separate components, was related to shooting behavior in these FPST conditions. The attentional control component of working memory was shown to be more related to shooting bias when compared to the capacity-related components, especially in the Mostly Incongruent condition (where most trials required making shooting decisions that go against racial stereotype). Study 2 used Confirmatory Factor Analysis to test whether attentional control ability was separate from proactive and reactive control strategy usage. Results showed that the attentional control ability was independent from which attentional control strategy was used. Finally, relating attentional control ability and attentional control strategies to shooting behavior, results showed that people with high attentional control and high proactive control usage were more likely to correctly adjust their expectations of threat in the Mostly Incongruent condition when compared to people with lower ability. People with low attentional control and high proactive control usage were more likely to adjust their expectations of threat based on racial stereotypes. Overall, these findings provide new insight into how cognitive ability interacts with shooting decisions in order to produce racial shooting bias.

In today's network-dependent society, cyber attacks with network worms have become the predominant threat to confidentiality, integrity, and availability of network computing resources. Despite ongoing research efforts, there is still no comprehensive network-security solution aimed at controling large-scale worm propagation. The aim of this work is fivefold: (1) Developing an accurate combinatorial model of worm propagation that can facilitate the analysis of worm control strategies, (2) Building an accurate epidemiological model for the propagation of a worm employing local strategies, (3) Devising distributed architecture and algorithms for detection of worm scanning activities, (4) Designing effective control strategies against the worm, and (5) Simulation of the developed models and strategies on large, scale-free graphs representing real-world communication networks. The proposed pair-approximation model uses the information about the network structure--order, size, degree distribution, and transitivity. The empirical study of propagation on large scale-free graphs is in agreement with the theoretical analysis of the proposed pair-approximation model. We, then, describe a natural generalization of the classical cops-and-robbers game--a combinatorial model of worm propagation and control. With the help of this game on graphs, we show that the problem of containing the worm is NP-hard. Six novel near-optimal control strategies are devised: combination of static and dynamic immunization, reactive dynamic and invariant dynamic immunization, soft quarantining, predictive traffic-blocking, and contact-tracing. The analysis of the predictive dynamic traffic-blocking, employing only local information, shows that the worm can be contained so that 40\% of the network nodes are not affected. Finally, we develop the Detection via Distributed Blackholes architecture and algorithm which reflect the propagation strategy used by the worm and the salient properties of the network. Our distributed detection algorithm can detect the worm scanning activity when only 1.5% of the network has been affected by the propagation. The proposed models and algorithms are analyzed with an individual-based simulation of worm propagation on realistic scale-free topologies.

Hand function is of great importance in the many daily activities that require well-coordinated hand and arm movements. Measurement of hand function is an essential element in the rehabilitation process, in order to facilitate medical diagnosis and determine developmental stages, functional levels, and the efficacy of treatment interventions. Basic requirements for any measurement used in clinics are that they are easy to use, relevant to the function being assessed, and valid and reliable. When scrutinizing the literature on hand function, important gaps were found with regard to measurement. For example, the reliability of grip strength with the Grippit in children has yet to be determined, and there are few evaluations of hand function measurements in Charcot-Marie-Tooth disease (CMT). Furthermore, laboratory measurements of hand function, which have the potential to provide more detailed information and insight into hand control, such as the role of the cerebellum in reactive grip control – have not been fully explored. The overall aim of the thesis was to achieve more knowledge on hand function; on the evaluation of measurements in different target populations; and on movement control of the hand. In the first study, the aim was to evaluate the test-retest reliability of the peak and sustained grip strength with Grippit in a sample of healthy children (n=58, 6-, 10- and 14-y-olds). This was followed by two studies examining hand function in an adult sample (n=20) diagnosed with CMT. The test-retest reliability of grip and pinch strength using Grippit, sensation with the Shape Texture Identification test (STI) and dexterity with the Box and Block Test (BBT) and Nine-Hole Peg test (NHP) were studied. The impact of the disease on daily life, measured with the Disability of the Arm, Shoulder and Hand questionnaire (DASH), and correlations between disability and various aspects of hand function, were also explored in this condition. The aim of the fourth study was to examine grip force response to unpredictable loadings of an object held in a pinch grip in subjects (n=9, 22-48 yrs) who had been diagnosed with a cerebellar lesion, compared with a healthy control group (n=11). The first study showed that test-retest reliability was good for both peak and sustained grip strength in healthy children. The mean and best of three trials were equally reliable, but differences in reliability were detected within different age groups. For example, the peak grip strength, best of three trials, was more reliable for the 6-y-olds (intraclass correlation coefficient (ICC)=0.96, standard error of measurement in percentage (SEM%)=6.3) and 14-y-olds (ICC=0.96, SEM%=5.2) compared with the 10-y-olds (ICC=0.78, SEM%=12.5). In the second study, evaluating measurements of hand function in subjects with CMT, grip strength proved to be reliable (ICC=0.99, coefficient of repeatability (CR)=26.7 N, coefficient of variation (CV)=6.6 %), but pinch strength was less reliable. The reliability was also good for the BBT (ICC=0.95, CR=11.5 blocks/min, CV=8.4%) and the NHP (ICC=0.99, CR=4.3 s, CV=3.9 %). However, a bias towards higher values was noted on the second test occasion with the BBT. The reliability of the STI test (kappa=0.87) was also very good in subjects with CMT. A limitation in this latter test was noted in terms of its ability to describe subjects either performing very well or very poorly. The results of the third study showed that hand function in CMT was reduced (p&lt;0.001) to about 60% of that in healthy controls in each of the separate outcome measures, as well as by a constructed summary index of hand function. The median DASH score was 38.8 (range 0-66.7) and was clearly related to hand function (r=0.64-0.83). The results of the final study in subjects with cerebellar lesions showed that the ipsilateral hand had delayed and more variable response latencies e.g. 278±166 ms for loads delivered at 2 N/s, compared with healthy subjects (HS) 80±53 ms (p=0.005). The cerebellar subjects also used a higher pre-load grip force with the ipsilateral hand (1.6±0.8 N) than the HS (1.3±0.6 N (p=0.017)). Even the contralateral hand in subjects with unilateral cerebellar stroke showed a delayed onset of the grip response. In conclusion: Grip strength assessment in children with Grippit results in good reliability for peak and sustained grip strength, although the 10-y-olds were less reliable. In CMT the tested instruments can all be used to evaluate hand function, but certain factors, such as the number of trials used should be taken into consideration. The CMT subjects’ hand function was reduced and correlated with their self-experienced disability. However, clinicians should be aware that patients might score lower than expected on DASH, possibly due to a long process of adaptation. Cerebellar lesions can impair the reactive grip control in both the ipsilateral and the contralateral hand. These investigations have thus, as intended increased the knowledge of hand function. The studies have evaluated some measurements in different samples, which will help clinicians testing hand function.

Nos travaux de recherches sont des travaux supports pour les gestionnaires de l’hôpital Robert Pax de Sarreguemines, et plus généralement de tout centre hospitalier pour développer des approches centrées sur le patient. Nous nous sommes inspirés des approches centrées sur le produit issues du domaine industriel qui ont été proposées pour répondre aux exigences croissantes de gestion des produits dans un environnement de plus en plus incertain. Par analogie, les systèmes de production de soins centrés patient peuvent être assimilés aux systèmes de production de biens centrés produit. Cependant, il ne faut pas perdre de vue la spécificité des systèmes de production de soins : le facteur humain. Cette spécificité est à l’origine de leur caractère complexe, aléatoire et imprévisible. Par ailleurs, les approches de pilotage, que ce soit dans le milieu industriel ou hospitalier, sont majoritairement des modèles mathématiques et des modèles de simulation utilisant une approche de gestion centrée sur une ou plusieurs ressources considérées comme critiques. C’est pourquoi il nous a paru judicieux d’opter pour une approche centrée patient basée sur le paradigme multi-agents. Nous proposons alors, un système multi-agents de pilotage réactif dynamique et distribué centré patient du parcours patient au sein des systèmes hospitaliers. L’alternative que nous proposons consiste à utiliser une approche centrée patient et basée sur les agents permettant de minimiser les délais d’attente, ainsi que la durée de séjour, et par conséquent les coûts des soins, tout en assurant un soin de qualité pour l’ensemble des patients et une meilleure gestion des ressources hospitalières / Through our research, we offer a support tool for the managers in Robert Pax hospital in Sarreguemine (France), and more generally any hospital center wishing to develop a patient centered approach. We were inspired by « product centered » approaches emerging from industrial domain which were proposed to answer the increasing requirements of products management. By analogy, health care systems patient centered can be assimilated to production systems product centered. However, it is important not to lose sight of the specificities of health care systems which is the human factor. This specificity makes this system complex, random and unpredictable. Besides, the approaches used in industrial or hospital environment, are mainly mathematical models and simulation approaches centered on one ore several resources categorized as critical. In that sense, it seemed judicious to choose a patient centered approach based on a multi-agent paradigm. We proposed a Reactive multi-agent control system of the patient flow in healthcare system. The proposed alternative is a patient centered approach allowing to minimize the patients waiting time and the length of their stay and consequently the care costs. The proposed approach also ensures the care quality and an optimal use of the hospital resources

A operação de um Sistema Elétrico de Potência é complexa, principalmente, devido ao grande número de restrições impostas às variáveis e às grandezas do sistema, sejam elas de natureza física ou de requisito para a qualidade e a continuidade do fornecimento de energia elétrica entregue aos consumidores. O gerenciamento das tensões e dos fluxos de potência, ativa e reativa, é crucial para que o SEP opere de modo seguro, com qualidade e com o menor custo. O gerenciamento, das tensões e das potências, é realizado através dos ajustes dos dispositivos de controle do SEP, contudo, determinar os estados dos dispositivos controlados do SEP não é uma tarefa trivial. A determinação dos estados dos dispositivos controlados torna-se ainda mais difícil, pois, para garantir o fornecimento, de energia elétrica, contínuo e de qualidade, diversos cenários (contingências) devem ser analisados e as ações de controle impostas ao SEP devem satisfazer todos os requisitos operacionais do SEP para todos os cenários. Diversos blecautes ocorreram devido à instabilidade de tensão no SEP e quando estão em condições de alto carregamento, o problema torna-se ainda mais evidente. Este trabalho propõe uma ferramenta computacional para o planejamento das ações de controles de reativo e tensão em Sistemas Elétricos de Potência que mantenham, ao longo do dia, as variáveis e as grandezas do sistema dentro da região factível de operação e, ainda, garantam margem de estabilidade de tensão suficiente para que o colapso de tensão seja evitado. Para desenvolver esta ferramenta, o problema de planejamento de controle de tensão e reativo foi formulado como um problema de otimização, onde, neste problema, dois objetivos e metodologias foram realizados. No primeiro, buscou-se determinar os estados dos dispositivos controlados que minimizassem as perdas nas linhas de transmissão dentro de um intervalo de tempo e de potência e, no segundo, determinar os estados dos dispositivos controlados que mantivessem as variáveis e grandezas do sistema dentro da região factível durante o maior intervalo de potência, minimizando, assim, as mudanças nas ações de controle do SEP. Também foi proposta, neste trabalho, uma metodologia para identificação de contingências críticas do SEP. Os resultados obtidos através das resoluções dos problemas indicaram que as formulações propostas são capazes de determinar os estados dos dispositivos controlados do sistema ao longo do dia, de modo a garantir que não ocorressem violações nas restrições operacionais do sistema enquanto houvesse medidas de controle, onde foi considerado o caso base e uma lista de contingências. Além disso, as margens de estabilidade de tensão do caso base e das contingências foram sempre mantidas acima do valor de segurança especificado. Os resultados também mostraram que a metodologia para identificação da contingência crítica proposta é capaz de identificar a contingência que limita o crescimento de carga do sistema, de modo a garantir que o SEP esteja operando com o menor risco à instabilidade de tensão, mantendo as variáveis e as grandezas do sistema dentro da região factível para o maior número de cenários. / The operation of an Electric Power System is complex, mainly due to the great number of restrictions imposed on the variables and the magnitudes of the system, whether of a physical nature or a requirement for the quality and continuity of the electricity supply delivered to consumers. The management of voltage and the power flow, active and reactive, is crucial for the safely operation of the Electric Power System, with quality and low cost. The management of the voltages and powers is performed through the adjustments of the Electric Power System control devices, however, determine the states of the Electric Power System controlled devices is not a trivial task. The determination of the states of the controlled devices becomes even more difficult, since, to guarantee the supply of electricity, continuous and of quality, several scenarios (contingencies) must be analyzed and the control actions imposed on the Electric Power System must satisfy all the Electric Power System operational requirements for all scenarios. Several blackouts occurred due to the voltage instability in the Electric Power System and when they are in high load conditions, the problem becomes even more evident. This work proposes a computational tool for the planning of the actions of reactive and voltage controls in Electric Power Systems that maintain, throughout the day, the variables and the magnitudes of the system within the feasible region of operation and, also, guarantee voltage stability margin sufficient to avoid the voltage collapse. To develop this tool, the planning problem of voltage control and reactive control was formulated as an optimization problem, where, in this problem, two objectives and methodologies were used. In the first one, it was tried to determine the controlled devices states that minimize the transmission lines losses at a time and power interval, and, in the second, to determine the controlled devices states that maintain the variables and quantities of the system within feasible region during the largest power interval, thus the control actions changes in the Electric Power Systems are minimize. Was also proposed, in this work, a methodology for identify the critical contingencies of Electric Power Systems. The results obtained through problem resolutions indicated that the proposed formulations are able to determine the controlled devices states of the system throughout the day, so that there were no violations of the system\'s operational constraints while there were control measures, assessment the base case and a list of contingencies. In addition, the base case and contingencies voltage stability margins have always been maintained above the specified safety value. The results also showed that the methodology for the identification of the critical contingency is able to identify the contingency that limits the system load growth, in order to ensure that the Electric Power Systems is operating with the lowest risk to voltage instability, maintaining the system variables and magnitudes within the feasible region for the largest number of scenarios.

A operação de um Sistema Elétrico de Potência é complexa, principalmente, devido ao grande número de restrições impostas às variáveis e às grandezas do sistema, sejam elas de natureza física ou de requisito para a qualidade e a continuidade do fornecimento de energia elétrica entregue aos consumidores. O gerenciamento das tensões e dos fluxos de potência, ativa e reativa, é crucial para que o SEP opere de modo seguro, com qualidade e com o menor custo. O gerenciamento, das tensões e das potências, é realizado através dos ajustes dos dispositivos de controle do SEP, contudo, determinar os estados dos dispositivos controlados do SEP não é uma tarefa trivial. A determinação dos estados dos dispositivos controlados torna-se ainda mais difícil, pois, para garantir o fornecimento, de energia elétrica, contínuo e de qualidade, diversos cenários (contingências) devem ser analisados e as ações de controle impostas ao SEP devem satisfazer todos os requisitos operacionais do SEP para todos os cenários. Diversos blecautes ocorreram devido à instabilidade de tensão no SEP e quando estão em condições de alto carregamento, o problema torna-se ainda mais evidente. Este trabalho propõe uma ferramenta computacional para o planejamento das ações de controles de reativo e tensão em Sistemas Elétricos de Potência que mantenham, ao longo do dia, as variáveis e as grandezas do sistema dentro da região factível de operação e, ainda, garantam margem de estabilidade de tensão suficiente para que o colapso de tensão seja evitado. Para desenvolver esta ferramenta, o problema de planejamento de controle de tensão e reativo foi formulado como um problema de otimização, onde, neste problema, dois objetivos e metodologias foram realizados. No primeiro, buscou-se determinar os estados dos dispositivos controlados que minimizassem as perdas nas linhas de transmissão dentro de um intervalo de tempo e de potência e, no segundo, determinar os estados dos dispositivos controlados que mantivessem as variáveis e grandezas do sistema dentro da região factível durante o maior intervalo de potência, minimizando, assim, as mudanças nas ações de controle do SEP. Também foi proposta, neste trabalho, uma metodologia para identificação de contingências críticas do SEP. Os resultados obtidos através das resoluções dos problemas indicaram que as formulações propostas são capazes de determinar os estados dos dispositivos controlados do sistema ao longo do dia, de modo a garantir que não ocorressem violações nas restrições operacionais do sistema enquanto houvesse medidas de controle, onde foi considerado o caso base e uma lista de contingências. Além disso, as margens de estabilidade de tensão do caso base e das contingências foram sempre mantidas acima do valor de segurança especificado. Os resultados também mostraram que a metodologia para identificação da contingência crítica proposta é capaz de identificar a contingência que limita o crescimento de carga do sistema, de modo a garantir que o SEP esteja operando com o menor risco à instabilidade de tensão, mantendo as variáveis e as grandezas do sistema dentro da região factível para o maior número de cenários. / The operation of an Electric Power System is complex, mainly due to the great number of restrictions imposed on the variables and the magnitudes of the system, whether of a physical nature or a requirement for the quality and continuity of the electricity supply delivered to consumers. The management of voltage and the power flow, active and reactive, is crucial for the safely operation of the Electric Power System, with quality and low cost. The management of the voltages and powers is performed through the adjustments of the Electric Power System control devices, however, determine the states of the Electric Power System controlled devices is not a trivial task. The determination of the states of the controlled devices becomes even more difficult, since, to guarantee the supply of electricity, continuous and of quality, several scenarios (contingencies) must be analyzed and the control actions imposed on the Electric Power System must satisfy all the Electric Power System operational requirements for all scenarios. Several blackouts occurred due to the voltage instability in the Electric Power System and when they are in high load conditions, the problem becomes even more evident. This work proposes a computational tool for the planning of the actions of reactive and voltage controls in Electric Power Systems that maintain, throughout the day, the variables and the magnitudes of the system within the feasible region of operation and, also, guarantee voltage stability margin sufficient to avoid the voltage collapse. To develop this tool, the planning problem of voltage control and reactive control was formulated as an optimization problem, where, in this problem, two objectives and methodologies were used. In the first one, it was tried to determine the controlled devices states that minimize the transmission lines losses at a time and power interval, and, in the second, to determine the controlled devices states that maintain the variables and quantities of the system within feasible region during the largest power interval, thus the control actions changes in the Electric Power Systems are minimize. Was also proposed, in this work, a methodology for identify the critical contingencies of Electric Power Systems. The results obtained through problem resolutions indicated that the proposed formulations are able to determine the controlled devices states of the system throughout the day, so that there were no violations of the system\'s operational constraints while there were control measures, assessment the base case and a list of contingencies. In addition, the base case and contingencies voltage stability margins have always been maintained above the specified safety value. The results also showed that the methodology for the identification of the critical contingency is able to identify the contingency that limits the system load growth, in order to ensure that the Electric Power Systems is operating with the lowest risk to voltage instability, maintaining the system variables and magnitudes within the feasible region for the largest number of scenarios.