Based on the Lyapunov stability theorem, two design methodologies of adaptive block backstepping controller is proposed in this thesis for a class of multi-input systems with matched and mismatched perturbations to solve regulation problems. The main difference between these two method is that perturbation estimations are only employed in each virtual control input in the second method, whereas in the first method, the perturbation estimation is only employed in the last block. According to the number of block (m) in the dynamic equations of plant to be controlled, m-1 virtual input controllers are designed from the first block to the (m-1)th block, and the proposed robust controller is designed from the last block. Adaptive mechanisms are employed in each of the virtual input controllers as well as the robust controller, so that the least upper bounds of perturbations and perturbation estimation errors are not required. Furthermore, the dynamic equations of the plant do not need to satisfy the block strict feedback form, and the resultant control system can achieve asymptotic stability or uniformly ultimately boundedness. Finally, a numerical example and a practical example are given for demonstrating the feasibility of the proposed control schemes.

In this thesis, digital controller design methods for sampled-data nonlinear systems are considered. Although sampled-data nonlinear control has attracted much attention in recent years, the controller design methods for sampled-data nonlinear systems are still limited. Therefore, a range of controller design methods for sampled-data nonlinear systems are developed such as backstepping, adaptive and robust backstepping, reduced-order observer-based output feedback controller design methods based on the Euler approximate model. These controllers are designed to compensate the effects of the discrepancy between the Euler approximate model and exact discrete time model, parameter estimation error in adaptive control and observer error in output feedback control which behave as disturbance. A dual-rate control scheme is presented for output-feedback stabilization of sampled-data nonlinear systems. It is shown that the designed controllers semiglobally practically asymptotically (SPA) stabilize the closed-loop sampled-data nonlinear system. Moreover, various applications of these methods are given and their performances are analyzed with simulations.

Based on the Lyapunov stability theorem, a design methodology of adaptive block backstepping controller is proposed in this thesis for a class of multi-input systems with mismatched perturbations to solve regulation problems. According to the number of block (m) in the plant to be controlled, m-1 virtual input controllers are designed from the first block to the (m-1)th block. Then the proposed robust controller is designed from the last block. Adaptive mechanisms are employed in each of the virtual input controllers as well as the robust controller, so that the knowledge of the least upper bounds of mismatched perturbations is not required. The resultant control system can achieve asymptotic stability. Finally, a numerical example and a practical example are given for demonstrating the feasibility of the proposed control scheme.

No description available.

Le développement de la commande d’un véhicule à pile à combustible et supercondensateurs doit prendre en compte les contraintes liées à l’association de ses composants. La commande par inversion apporte une solution. Elle utilise une approche systémique et cognitive afin d’identifier la cause qui produit l’effet désiré et inverse les modèles des éléments associés pour obtenir une structure de commande. Ainsi, les commandes déduites de la Représentation Energétique Macroscopique (REM) et du Backstepping font partie de la catégorie des commandes par inversion. Le Backstepping déduit une commande stable de la plupart des systèmes non-linéaires. Cependant, il ne permet pas de gérer de façon claire et efficace les couplages énergétiques. Il est alors possible de décomposer physiquement le système suivant les règles de la REM. La REM permet également de séparer explicitement la commande et la stratégie de gestion de l’énergie. Dans cette thèse en cotutelle franco-québécoise, les caractéristiques des deux commandes ont été soulignées. Les deux méthodes apparaissent alors complémentaires. L’intégration du Backstepping apporte à la REM l’assurance d’une stabilité intrinsèque. Les principes de la REM, quant à eux, permettent au Backstepping de gérer les couplages énergétiques. Le développement d’une commande par inversion stable d’un véhicule à pile à combustible et supercondensateurs est donc proposé par la combinaison de ces deux méthodes de commande, suivant une procédure d’inversion combinée. La répartition des puissances du véhicule est ainsi réalisée en temps réel, sur dispositif expérimental, suivant une stratégie de filtrage et la commande stable par inversion combinée développée. / The development of the control of a fuel cell/supercapacitor vehicle must take into account the constraints related to the associations of its components. Inversion based control can solve this problems. This use a systemic and cognitive approach to find the cause which produce the desired effect and inverse the associated component models to obtain a control structure. In this way, Energetic Macroscopic Representation (EMR) and Backstepping have inversion based control approach. The Backstepping method deduces stable control of most classes of nonlinear systems. However, it don’t effectively and simply manage the energetic couplings. A physical decomposition of the studied system following the EMR rules bring a solution. EMR enables a systematic deduction of control schemes, specifically a clear distinction between the local control and the energy management strategy level. In this franco-quebecer co-tutorial thesis, similarities between the both control methods has been shown. EMR and Backstepping can complement each other. The integration of the Backstepping bring intrinsic stability to the EMR. The Backstepping can manage the energetic couplings thanks to EMR. The development of a fuel cell/supercapacitor vehicle stable inversion based control is then proposed using the combination of the both control methods. Thus, the power distribution is achieve in real time using a filtering strategy and the stable proposed combined inversion based control.

The use and practical applications of small UAV systems has continually grown in the past several years in both the public and private sectors. These UAV systems are used for not only defensive purposes, but for commercial applications such as exterior bridge and home inspections, wildlife/wildfire management and observation, conservation exercises, law-enforcement, radio-repeating operations, and a wide variety of other uses that may not warrant the use, expense, space constraints, or risk of a manned aircraft. This thesis focuses on the design of a fixed pitch multirotor UAV system for use in furthering research projects and facilitating payload data collection from a flying platform without the expense or risk of testing with available larger UAV systems. The design of a multirotor UAV system with a flight control scheme, communication architecture and hardware, electrical architecture and hardware, and mechanical design is presented. An Extended Kalman Filter (EKF) strategy is implemented aboard a developed Inertial Measurement Unit (IMU) to estimate vehicle state. Experiments then validated the estimates from the EKF through a comparative approach between the developed unit and a commercial unit. A nonlinear flight control system is implemented based on an Integral-Backstepping control strategy. The flight control strategy was then fully simulated and exhaustively tested under a variety of external disturbances and initial conditions from a fully dynamic modeled environment. Parameters about the vehicle were experimentally determined to increase the accuracy of the model which would increase the chances of successful flight operations. Flight demonstrations were conducted to evaluate the abilities and performance of the control system, along with testing the interface abilities and reliability between a universal ground control station (UGCS) and the aircraft. Lastly, the model was revisited with the input data from the flight control experiment and the output captured was evaluated against the output of the model system to evaluate effectiveness, reliability, and accuracy of the model. The results of the comparison showed that the computer simulation was accurate in predicting attitude and altitude of the vehicle to that of the realized system. / Master of Science

The work in this thesis is on two topics. The first topic focuses on collaboration between a UAV and a UGV to track a moving ground target. The second topic focuses on deriving a guidance law for a small-scale controllable projectile to be guided into a target. For the first topic, we implement a path planning algorithm in a hardware system for a UAV and UGV to track a ground target. The algorithm is designed for urban environments where it is common for objects to obstruct sensors located on the UAV and the UGV. During the hardware system's implementation, multiple problems prevented the hardware system from functioning properly. We will describe solutions to these problems. For the second topic, we develop a guidance law for a small-scale controllable projectile using Lyapunov analysis techniques. We implement a PID controller on the body-axes pitch rate and yaw rate of the projectile such that the behavior of the pitch rate and yaw rate can be approximated as a second order system. We derive inputs for the pitch rate and yaw rate using backstepping and adaptive control techniques. The guidance law we develop guarantees the rocket will point at its intended destination. Additionally, we present expressions for the kinematics and dynamics of the rocket's motion and define the forces and moments that act on the rocket's body.

No description available.

No description available.

Yes / In this technical note, stochastic coupling attenuation is investigated for a class of multi-variable bilinear stochastic systems and a novel output feedback m-block backstepping controller with linear estimator is designed, where gradient descent optimization is used to tune the design parameters of the controller. It has been shown that the trajectories of the closed-loop stochastic systems are bounded in probability sense and the stochastic coupling of the system outputs can be effectively attenuated by the proposed control algorithm. Moreover, the stability of the stochastic systems is analyzed and the effectiveness of the proposed method has been demonstrated using a simulated example.