Conventional electrohydraulic solutions integrate easily into modern machine concepts by utilizing field bus technology. Nevertheless, most use cases are limited to machine automation concepts. Integration into higher-level data and IoT systems is the key for positioning of electrohydraulic solutions within the factory of the future. CytroConnect is a new approach for the integration of electrohydraulic systems into IoT environments and the corresponding market offerings. Bosch Rexroth decided not only to integrate IoT-ready features like pre-installed sensor packages but also a modular automation concept providing decentralized intelligence with an open multi-ethernet interface. An edge-to-cloud connectivity stack operated by Bosch turns the target into a Connected Product. The convergence of physical and digital product can be realized. Based on that the digital service CytroConnect solves concrete holistic use cases like visualization and condition monitoring by offering a web-based dashboard of all relevant sensor data that is accessible everywhere. Modular paid add-ons offered as risk-free monthly subscriptions address further smart maintenance and prediction use cases.

La qualité de la dérivation numérique en ligne d’un signal bruité joue un rôle primordial dans diverses applications touchant différents domaines (1D et 2D). Dans le travail présenté, nous nous sommes intéressés aux dérivateurs type "signal". Nos travaux s’inscrivent dans ce contexte et abordent des aspects théoriques et applicatifs. Du point de vue théorique, une étude de deux familles de dérivateurs a été effectuée. En premier lieu, nous avons étudié les dérivateurs de nature algébrique [travaux du projet INRIA-Non-A] et en deuxième lieu les différentiateurs modes glissants d’ordre supérieur [travaux de Levant]. Cette étude nous a permis de décrire les points forts et les points faibles de chacune de ces approches. Suite à cette étude, une nouvelle version des dérivateurs modes glissants a été proposée. Du point de vue applicatif, une première application dans le domaine 1D est présentée et qui consiste à utiliser le dérivateur proposé pour l’identification paramétrique en ligne d’un robot SCARA à deux axes. La méthode d’identification est validée expérimentalement par comparaison des résultats obtenus avec ceux donnés par d’autres méthodes (méthode en ligne et hors ligne). La deuxième application touche au domaine 2D. Dans ce cas, nous proposons l’application du différentiateur pour la détection des contours dans une image. Pour la validation des résultats, différents essais sont réalisés pour différents types de bruits. Une étude comparative avec des méthodes classiques est effectuée. Pour pouvoir tester l’efficacité du différentiateur dans des boucles de commande nous nous sommes intéressés aux systèmes électrohydrauliques. Le système physique étudié est un servo-vérin électrohydraulique à hautes performances ayant différents modes de fonctionnement. Après une succession d’hypothèses effectuées sur le modèle de simulation, des modèles de commande sont fournis. La dernière partie de ces travaux est dédiée à la synthèse de stratégie de commande via la technique du Backstepping pour le positionnement de l’axe électrohydraulique afin de tester l’efficacité l’algorithme proposé dans des boucles de commande. Comme base de comparaison, la version classique des algorithmes modes glissants est aussi utilisée. / The quality of the on-line differentiation with a noisy signal plays an important role in various applications involving different areas (1D and 2D). In the present work, we were interested particularly to differentiation method which requires a minimal knowledge on the noise and/or the input signal. Our work is registred in this context and address both aspects theoretical and applications. From the theoretical point of view, a study of two families of differentiation algorithm was performed. Firstly, we studied the algorithm based on the algebraic development [the work of the project INRIA-ALIEN] and secondly the differentiators of higher order sliding modes [work Levant] for detailed study. This study allowed us to describe the advantages and disadvantages of each approach. Following this study, a new version of sliding modes differentiator was proposed, this last one being the main theoretical contribution of this thesis. To test the efficiency of the proposed version, differents applications were carried out. The first application in 1D is shown, which consists in use the proposed differentiator for online parametric identification of a two-axis SCARA robot. The identification method is validated experimentally by comparing the results obtained with those given by other methods (method online and offline). The second application relates to the 2D domain. In this case, we propose the implementation of the differentiator for the edge detection in an image. To validate the results, various tests are carried out for different types of noise. In order to have some comparison basis, we use the filter Canny and Prewitt masks and the gradient. To test the effectiveness of the differentiator in control loops we are interested in electrohydraulic systems. For this, a model of the hydraulic and mechanical system is made. After a consideration of some assumptions on the simulation model, the control models are provided. To separate the dynamic servovalve/ actuator, a local study is performed. The last part of this work is dedicated to the synthesis of control strategy through the backstepping technique for the positioning of the electro-hydraulic axis in order to test the effectiveness of the proposed algorithm in the control loop. As a basis for comparison, the classic version of sliding mode algorithm is also used.

Les systèmes électro-hydrauliques sont largement utilisés dans l’industrie pour des contrôles de position ou d’effort. Cependant, à cause des non-linéarités du système électro-hydraulique, il est difficile d’établir un modèle précis valable sur une large bande de fréquences et de grands mouvements. Le travail de cette thèse concerne un banc d’essai électro-hydraulique qui comporte trois composants hydrauliques principaux, à savoir deux servovalves haute performance, un vérin à double tige, et une embase spécifique qui relie les servovalves et le vérin. Ce banc d’essai a été conçu pour tester des composants aéronautique et automobile dans des conditions réelles (par exemple, tests d'usure ou de vieillissement). Le premier objectif principal de cette thèse concerne la mise en œuvre d’un prototype virtuel basé sur un modèle précis issu de considérations physiques et d'un travail expérimental afin d'identifier les paramètres et de valider le réalisme du prototype virtuel. Le deuxième objectif est d'élaborer des lois de commande non-linéaires sophistiquées avec une large plage de fonctionnement et une bonne robustesse aux perturbations. Le modèle proposé basé sur le Bond Graph montre une très bonne adéquation entre les résultats de simulation et les résultats expérimentaux non seulement en basses fréquences, mais également en fréquences élevées. En particulier, les performances en hautes fréquences sont nettement améliorées par l'introduction des effets dynamiques liés à l’embase. En outre, des lois de commande, respectivement basées sur le backstepping et sur la commande sans modèle, ont été élaborées et mises en œuvre sur le banc d’essai. Toutes les lois de commande proposées ont été validées à la fois en simulation et expérimentalement. Les résultats montrent qu’ils conduisent à de meilleures performances en suivi de position et en robustesse par rapport aux lois de commande classiques. / Hydraulic systems are widely applied in industry for position or force control. However, due to hydraulic system nonlinearities, it is difficult to achieve a precise model valid over a large range of frequencies and movements. The work in this dissertation focuses on a high performance hydraulic test bench which involves three main hydraulic components, i.e. two high performance servovalves, a double rod actuator, and a specific intermediate block connecting the servovalves and actuator. This rig has been designed for testing aerospace or automotive components in real conditions (e.g. wear and ageing effects). The main objectives of this dissertation are first the development of a virtual prototype based on a precise model which is derived from the physical principles and experimental works, and then second the synthesis of several nonlinear control laws of this actuation system in a large operating range with a good robustness to the perturbations. The proposed model based on Bond Graph shows a very good agreement with experimental results not only at low frequencies, but also at high frequencies. Moreover, its performances are improved at high frequencies by introducing the dynamic effects due to the intermediate block. Besides, multivariable and monovariable control strategies, based on respectively the backstepping and the model-free method, are developed and implemented on the test bench. All the control strategies proposed have been validated by simulations and experiments. Results show they lead to better tracking precision and robustness performance compared to the conventional control techniques.

The diploma thesis is focused on design of electrohydraulic system for nose gear control on small civil airliners. First part consists of brief review of small civil airliners, nose gears and CS 23 restrictions relevant for the design. In practical part a typical small civil airliner is defined and kinematic of landing gear mechanisms is designed. Then the electrohydraulic system itself is designed and parameters of some components are suggested. The wheel steering mechanism is simulated and, in conclusion, the whole system is evaluated.

In recent years, additive manufacturing (AM) has become one of the most revolutionary and promising technologies in manufacturing. The process of making a product layer by layer is also often referred to as 3D printing. Once employed purely for prototyping, AM is now increasingly used for small series production, for example in aerospace applications. The paper starts with a motivation for AM in hydraulic applications and the development of an AM internal gear pump. For a better understanding of the manufacturing process, a brief introduction to AM highlighting the advantages and challenges is given. The AM internal gear pump is part of an electrohydraulic power pack, which is used to power an electrohydraulic actuator (EHA). The power pack contains all necessary peripherals to realise the hydraulic system of the EHA. The AM process allows for new design possibilities, but the process differs strongly compared to subtractive manufacturing processes and therefore is outlined here. The paper concludes by presenting measurement results of the AM internal gear pump.

Virtualization of products means the representation of some of their properties by models. In a stronger digitalized world, these models will gain a much broader use than models had in engineering so far. Even for one modelling aspect different models of the same product will be used, depending on the specific need of the model user. That need may change in the course of product life, between first product concepts till over the different phases of development, to product use, maintenance, or even recycling. Since a digitalized world use of these diverse models will not be limited to experts model consistency will play a much stronger role. Model hierarchies will play a stronger role and can serve also as means for teaching product users a deeper understanding of product properties. A consistent model hierarchy leading from a simple to a more advanced property representation can support this learning process. In this paper perturbation methods are analyzed as a means for setting up model hierarchies in a consistent manner. This is studied by models for the behavior of a electrohydraulic drive, which consists of a variable speed motor, a pump, a double stroke cylinder and a counterbalance valve. Model hierarchy is achieved by model reduction in the sense of perturbation theory. The use of these different models for different questions in a system design context and their interrelations are exemplified.