Cette thèse vise à améliorer le positionnement statique et la précision de suivi de trajectoire des Robots Parallèles à Câbles (RPC) tout en prenant en compte leur élasticité globale. A cet effet, deux stratégies de commandes complémentaires valables pour toute configuration de RPC sont proposées.Tout d'abord, une analyse de robustesse est réalisée pour aboutir à une commande robuste des RPC référencée modèle. Un modèle de RPC approprié est défini en fonction de l'application visée et les principales sources d'erreurs de pose de la plate-forme mobile sont identifiées.Une première méthode de commande est proposée sur la base des résultats de l'analyse de robustesse. Cette première méthode réside dans le couplage d'une commande référencée modèle d’un contrôleur PID.Dans le cadre de cette thèse, un modèle élasto-dynamique de RPC est exprimé afin de compenser le comportement oscillatoire de sa plate-forme mobile dû à l'élongation des câbles et de son comportement dynamique.La deuxième méthode de commande utilise des filtres "input-shaping" dans la commande référencée modèle proposée afin d'annuler les mouvements oscillatoires de la plate-forme mobile. Ainsi, le signal d'entrée est modifié pour que le RPC annule automatiquement les vibrations résiduelles. Les résultats théoriques obtenus sont validés expérimentalement à l'aide d'un prototype de RPC non redondant en actionnement et en configuration suspendue. Les résultats expérimentaux montrent la pertinence des stratégies de commande proposées en termes d'amélioration de la précision de suivi de trajectoire et de réduction des vibrations. / This thesis aims at improving the static positioning and trajectory tracking accuracy of Cable- Driven Parallel Robots (CDPRs) while considering their overall elasticity. Accordingly, two complementary control strategies that are valid for any CDPR configuration are proposed.First, a robustness analysis is performed to lead to a robust model-based control of CDPRs. As a result, an appropriate CDPR model is defined as a function of the targeted application and the main sources of CDPR moving-platforms pose errors are identified.A first control method is determined based on the results of the robustness analysis. This first method lies in the coupling of a model-based feed-forward control scheme for CDPR with a PID feedback controller.Here, an elasto-dynamic model of the CDPR is expressed to compensate the oscillatory motions of its moving-platform due to cable elongations and its dynamic behavior.The second control method uses input-shaping filters into the proposed model-based feed-forward control in order to cancel the oscillatory motions the movingplatform. Thus, the input signal is modified for the CDPR to self-cancel residual vibrations.Experimental validations are performed while using suspended and non-redundant CDPR prototype. The proposed feed-forward model-based control schemes are implemented, and their effectiveness is discussed.Results show the relevance of the proposed control strategies in terms of trajectory tracking accuracy improvement and vibration reduction.

Les robots manipulateurs sont généralement des machines rigides, conçues pour que leurflexibilité ne perturbe pas leurs mouvements. En effet, des flexibilités mécaniques importantesdans la structure d’un système introduisent des degrés de liberté supplémentaires dont le comportementest complexe et difficile à maîtriser. Cependant, la réduction de la masse d’un systèmeest bénéfique du point de vue des coûts, de la performance énergétique, de la sécurité et des performancesdynamiques. Afin de faciliter l’accès aux nombreux avantages d’une structure légèremalgré la présence de fortes flexibilités, cette thèse porte sur la modélisation, la conception et lacommande de robots manipulateurs flexibles. Elle est motivée par le projet YAKA, dont l’applicationest le lancement et la récupération de drones à voilure fixe depuis un navire faisant route.Cette application nécessite une importante dynamique sur un vaste espace de travail, bien au-delàdes spécifications des robots rigides classiques. Les outils de modélisation, de conception et decommande proposés prennent en compte la flexibilité des segments et des articulations, pour unnombre quelconque de degrés de liberté et de segments flexibles. Le modèle dynamique flexibleest obtenu par le formalisme de Lagrange, les poutres flexibles sont représentées par le modèled’Euler-Bernoulli. Le schéma de commande proposé se décompose en une inversion de modèledynamique rigide et un bloc de précommande par Input Shaping adapté aux robots manipulateursflexibles. Les outils de conception proposés permettent de baser le processus de conceptionsur des performances prédites du système complet muni de ses actionneurs et de son contrôleuravec une simulation réaliste. Les validations expérimentales effectuées sur le robot YAKA permettentde valider la pertinence de la démarche suivie. Les résultats du projet YAKA confirment lafaisabilité de la mise en oeuvre d’un robot flexible de grande envergure et à forte dynamique dansun contexte industriel, en particulier pour le lancement et la récupération d’un drone à voilurefixe depuis un navire faisant route. / Robot manipulators are generally stiff machines, designed in a way that flexibility does not affecttheir movements. Indeed, significant flexibility introduces additional degrees of freedom witha complex behavior. However, reducing the mass of a system allows for costs, performance, andsafety improvements. In order to allow those benefits despite important flexibility, this thesis focuseson modeling, design and control of flexible robot manipulators. It is motivated by the YAKAproject, which aims at developing a robot to launch and recover fixed wing UAVs from a movingship. It implies reaching very high dynamics on a large workspace, way beyond the specificationsof common rigid robots. The proposed tools for modeling, design and control allow for taking intoaccount both joint and link flexibility, for any number of degrees of freedom and flexible links.The elastodynamic model is obtained with Lagrange principle, each flexible link being representedwith one ormany Euler-Bernouilli beams. The proposed control scheme uses a nonlinear rigiddynamic inversion and extends classical Input Shaping techniques to flexible robot manipulators.The proposed design tools allow for performance prediction of the system including its actuatorsand controllers thanks to a realistic simulation. Experiments conducted with the YAKA robot validatedthe proposed approach. The results of the YAKA project confirmed the feasibility of usinga large scale, highly dynamic flexible robot in an industrial context, in particular for UAVs launchand recovery operations from amoving ship.

Command shaping creates reference commands that reduce residual vibrations in a flexible system. This thesis examines the use of command shaping for flexible system control in three industrial applications: cam-follower systems, sloshing liquids, and cherrypickers. One common type of command shaping is command smoothing which creates a smooth transition between setpoints. A specific type of command smoothing used in cam-follower systems is the polynomial profile. An alternative technique to reduce vibration in flexible systems is input shaping. In this thesis, input-shaped commands are compared to polynomial profiles for applications requiring both vibration suppression and fast motion. Simulation and experimental results show that input shaping is faster than polynomial profiles and provides a simple approach to suppressing residual vibration. Secondly, significant experimental contributions have been made in the area of slosh control. The oscillation of liquids in a container can cause liquid spillage or can cause stability issues, especially in space vehicles. In the past, a number of control techniques have been proposed, but only a few recommend the use of input shaping. This thesis describes the use of command shaping to limit slosh. Results are supported by numerical and experimental testing. Input-shaped commands reduce residual slosh amplitude compared to unshaped commands and polynomial profiles. Input-shaped commands can also accommodate uncertainties and changes in the sloshing frequencies. Lastly, a small-scale cherrypicker was constructed to study the use of input-shaping control on these types of aerial lifts. Cherrypickers have flexible dynamic effects that can cause dangerous and life-threatening situations. To study this class of machines and to provide future students an experimental testbed, several design criteria were established before construction began. The resulting machine achieved most design objectives, including a simple-to-use graphical user interface and accurate state measurements. Robust input-shaping controllers were implemented to limit endpoint vibration. The design of the cherrypicker is discussed and experimental results are reported.

Cranes are widely used in material-handling and transportation applications, e.g. in shipyards, construction sites, and warehouses. As they are critical to the economic vitality of modern-day industries, improving crane performance and ease of use are important contributors to industrial productivity, low production costs, and workplace safety. In a typical crane operation, a payload is lifted, moved to its destination, and then lowered into place. This dissertation aims to improve crane performance and reduce task difficulty for the human operator in the movements mentioned above, namely: 1) Moving payloads laterally in the horizontal plane, 2) Lifting payloads off the ground, and 3) Lowering or laying down payloads on the ground. The design of a novel and intuitive human-machine control interface is the focus for improving operations that involve moving payloads laterally. The interface allows operators to drive a crane by simply moving a hand-held device through the desired path. The position of the device, which is tracked by sensors, is used to generate command signals to drive the crane. This command is then input-shaped such that payload oscillations are greatly reduced, making it much easier for the operator to drive the crane. Several facets of this crane control method are examined, such as control structure and stability, usability contexts, modes of operation, and quantitative measures (by means of human operator studies) of performance improvements over standard crane control interfaces. Lifting up a payload can be difficult for the operator, if the hoist is not properly centered above the payload. In these potentially dangerous and costly ``off-centered" lifts, the payload may slide on the ground and/or oscillate in the air after it is hoisted. Newtonian and Coulomb friction models that focus on the stiction-sliding-separation contact dynamics are derived and experimentally verified to study off-centered lifts. Then, with the goal of aiding operators during lift operations, simple but practical, self-centering solutions are proposed and implemented. Laying down or lowering a payload to the ground can also be challenging for operators in certain situations. For example, laying down a long, slender payload from a vertical orientation in the air, to a horizontal position on a flat surface. If the operator does not properly coordinate the motions of the crane in the vertical and horizontal directions simultaneously, then the potential hazards that may occur during these operations include: 1) slipping of the pivot about which the payload rotates, leading to sudden and dangerous payload movements; and 2) excessive hoist cable angles that lead to ``side-pull" problems. Newtonian and Coulomb friction models are derived to describe this lay-down scenario. The forces and motions experienced by the payload are then used to determine the motion trajectories that the crane and payload should follow to execute a successful lay-down maneuver. Finally, a special chapter is included to address the oscillation control of systems that have on-off nonlinear actuators, such as cranes powered by relay-controlled circuits. Due to their simplicity, ruggedness, and long service life, this type of crane can be commonly found in older factories or in applications where precise motion control is not a strict requirement. However, controlling payload oscillations on this type of crane is challenging for two reasons: 1) Relays that can only be turned on or off allow for only limited control over the crane velocity; and 2) These cranes typically have nonlinear asymmetrical acceleration and deceleration properties. Methods are derived for determining the relay switch-times that move single-pendulum and double-pendulum payloads with low residual oscillations.

Heavy-lifting machines such as cranes are widely used at ports, construction sites, and manufacturing plants in a variety of material-transporting applications. However, cranes possess inherent flexible dynamics that make fast and precise operation challenging. Most cranes are driven by human operators, which adds another element of complexity. The goal of this thesis is to develop controllers that allow human operators to easily and efficiently control machines with flexible dynamics. To improve the ease of human operation of these machines, various control structures are developed and their effectiveness in aiding the operator are evaluated. Cranes are commonly used to swing wrecking balls that demolish unwanted structures. To aid the operator in such tasks, swing-amplifying controllers are designed and their performance are evaluated through simulations and experiments with real operators. To make maneuvering of these machines in material-transporting operations easier, input-shaping control is used to reduce oscillation induced by operator commands. In the presence of external disturbances, input shaping is combined with a low-authority feedback controller to eliminate unwanted oscillations, while maintaining the human operator as the primary controller of the machine. The performance and robustness of the proposed controllers are thoroughly examined via numerical simulations and a series of experiments and operator studies on a small-scale mobile boom crane and a two-ton dual-hoist bridge crane.

Mobile boom cranes are used throughout the world to perform important and dangerous manipulation tasks. Given their mobility, these types of cranes can quickly be moved into position. Generally, their base is then fixed and stabilized before they start lifting heavy materials. The usefulness of these cranes can be greatly improved if they can utilize their mobile base during the lifting and transferring phases of operation. This ability greatly expands the workspace by combining base motion with the rotation, lifting, and luffing motions. Of course, the cranes lose some stability margin when a payload is attached. The stability is further degraded when the payload swings. This Master's Thesis presents a stability study of such cranes. As a first step, a static stability analysis of a boom crane is conducted in order to provide basic insights into the effects of the payload weight and crane configuration. Then, a semi-dynamic method is used to take the payload swing into account. As a final step, the results of a dynamic stability analysis obtained by using a multi-body simulation of the boom crane are compared to the outcomes of the previous approaches. This provides conclusions for the practical application of stability analysis. A control method that limits payload swing, and thereby improves stability, is also presented.

FDM 3D printing is an additive manufacturing technology that is widely used, mainly for rapid prototyping. It is also one of the cheapest and most accessible AM technologies for consumers. FDM printers, and especially cheaper alternatives, can have problems with creating high quality prints. Reasons include poor design, inaccurate construction, cheap components, and improper tuning. Input shaping is a control technique that may help mitigate defects caused by poor mechanical design or construction. The “ringing” defect may be eliminated by applying this solution. To perform an evaluation in sub-optimal mechanical conditions a 3D printer was constructed with a cantilever design mainly using plastic prints for mechanically important parts. Printing tests were done with and without input shaping. The results that were produced showed a direct effect of input shaping in 3d printers. / FDM 3D-printing är en additiv tillverkningsteknik som är mycket använd, främst för snabb prototypering. Det är också en av de billigaste och mest tillgängliga AM-teknikerna för konsumenter. FDM skrivare, och särskilt billigare alternativ, kan ha problem med att skapa högkvalitativa utskrifter. Orsaker inkluderar dålig design, konstruktionfel, billiga komponenter och felaktig justering. Input shaping är en kontrollteknik som kan hjälpa till att mildra defekter som orsakas av dålig mekanisk design eller konstruktion. "Ringning" defekten kan elimineras genom att tillämpa denna lösning. För att utföra en utvärdering i dåliga mekaniska förhållanden konstruerades en 3D-skrivare med en fribärande design som använder plastutskrifter för mekaniskt viktiga delar. Utskriftstester gjordes med och utan input shaping. Resultaten som framställdes visade på en uppenbar förbättring av print kvalité som en direkt effekt av input shaping.

L'alimentation en composants est un problème majeur dans la conception des systèmes de production et plus particulièrement d'assemblage. Un système d'alimentation doit garantir la position et l'orientation des composants qu'il fournit au système d'assemblage, quelle que soit la taille des composants. En revanche, le niveau de précision sera généralement d'autant plus important que les composants sont petits. Nos travaux ont été réalisés dans le contexte de l'alimentation en composants de taille millimétrique à microscopique avec des objectifs de modularité et de haute précision de positionnement. La première contribution de la thèse a consisté à élaborer une stratégie pour l'alimentation de haute précision en composants millimétriques pour une architecture ouverte, flexible et standardisée, proposée par un projet européen EUPASS (Evolvable Ultra Precision ASembly System). Un système standard a ainsi été développé. Il est modulaire, reconfigurable pour différents types de minicomposants et permet leur maintien micrométrique. Sur la base de ces travaux, nous avons étendu notre étude aux systèmes de micro-assemblage (microusine). L'objectif était de déplacer dans un plan des micro-objets jusqu'à une position donnée. L'idée retenue se fonde sur l'utilisation des vibrations pour entraîner ces micro-objets par inertie. Il a donc été nécessaire de caractériser les interactions entre la surface du système d'alimentation et la surface du micro-objet. Pour cela nous avons élaboré une méthode pour évaluer directement la force concernée qui est la force de friction. Le contrôle des vibrations du système a ensuite été conçu. Le pas de déplacement d'un micro-objet en fonction de ses caractéristiques est alors maîtrisé. Enfin, une boucle d'asservissement permet de contrôler le déplacement des micro-objets jusqu'à une position consigne.

Helicopters are often used to transport supplies and equipment. When a heavy load is carried via suspension cables below a helicopter, the load oscillates in response to helicopter motion and disturbance forces, such as wind. This oscillation is dangerous and adversely affects control of the helicopter, especially when carrying large or heavy loads. By adding input shaping to the helicopter's flight controller, the suspended load oscillation caused by helicopter motion is greatly reduced. A significant benefit of this approach is that it does not require measurement of the load position. This thesis contains derivations and analysis of simple planar helicopter-load dynamic models, and these models are verified using experimental data from model-scale, radio-controlled helicopters. The effectiveness of input shaping at eliminating suspended load oscillation is then demonstrated on this experimental hardware. In addition, the design of an attitude command, near-hover flight controller that combines input shaping and a common flight control architecture is illustrated using dynamic models of a Sikorsky S-61 helicopter, and simulation results are shown for example lateral and longitudinal repositioning movements. Results show that applying input shaping to simulated pilot commands greatly improves performance when carrying a suspended load.

Bridge and gantry cranes are crucially important elements in the industrial complex; they are used in many areas such as shipping, building construction, steel mills, and nuclear facilities, just to name a few. These types of systems tend to be highly flexible in nature, generally responding to commanded motion with oscillations of the payload and hook. The response of these systems to external disturbances, such as wind, is also oscillatory in nature. Often, the oscillations of the hook and payload have undesirable consequences. For instance, precise manipulation of payloads is difficult when cable sway is present. Oscillation of the hook can also present a safety hazard. For these reasons, the ability to successfully negate these detrimental dynamics can result in improved positioning, quicker settling time, and improved safety. This thesis addresses the dynamic properties of bridge and gantry cranes in an effort to develop a control scheme that enables strides to be made in these areas of positioning, efficiency, and safety. The fundamental advancement arising from this thesis is the development of a control scheme that enables precise positioning of the payload while motion and disturbance-induced oscillations are eliminated. A command generation technique uniquely suited for reducing oscillation in low-frequency flexible systems is examined and utilized in the control. The control scheme is implemented on a 10-ton bridge crane for validation purposes.