A decubitus preventing adaptive mat inspired by snail tentacles. - In: Bionik: Patente aus der Natur, (2013), S. 212-217
Control of chains of mass points in a frictional environment. - In: IUTAM Symposium on Nonlinear Dynamics for Advanced Technologies and Engineering Design, (2013), S. 421-433
Application of the TRIZ creativity enhancement approach to design of passively compliant robotic joint. - In: The international journal of advanced manufacturing technology, ISSN 1433-3015, Bd. 67 (2013), 1/4, S. 865-875
The essence of the conceptual design is getting the innovative projects or ideas to promise the products with best performance. It has been proved that the theory of inventive problem solution (TRIZ) is a systematic methodology for innovation. The design of a passively compliant robotic joint as an engineering example is illuminated in this paper to show the significance and approaches of applying TRIZ into getting the creative conceptual design ideas. In the robotic joints with passively compliance, the joints are composed of mechanical components such as springs and dampers as internal elements, which absorb the excessive collision force. Passive compliant joints with springs and dampers ensure a smooth contact with the surroundings, especially if robots are in contact with humans, but the passive compliant joints cannot determine precisely the position of the members of the joint or direction of the collision force. The main aim of this work is to show a systematic methodology for innovation as an effective procedure to enhance the capability of developing innovative passive compliant robotic joint and to overcome the main design problems. The TRIZ method will be utilized in order to eliminate the technical contradictions which appear in the passively compliant robotic joint.
https://doi.org/10.1007/s00170-012-4530-4
Identification of material defects in metallic materials using Lorentz force eddy current testing : fundamentals, metrological implementation and verification, 2013. - Online-Ressource (PDF-Datei: VII, 129 S., 18,71 MB) : Ilmenau, Techn. Univ., Diss., 2013
Parallel als Druckausg. erschienen
Der Einsatz von metallischen Werkstoffen ist in Industrie und Baugewerbe von enormer Bedeutung. Die immer stärkere Ausnutzung bis zur Grenze der Belastbarkeit eines Materials macht eine genaue Untersuchung des eingesetzten Metalls erforderlich. Um sicherzustellen, dass ein Bauteil fehlerfrei ist und den geforderten Belastungen standhalten wird, ist meist eine 100%ige Überprüfung notwendig. Dazu steht eine Auswahl an zerstörungsfreien Werkstoffprüfverfahren zur Verfügung. Die Anwendbarkeit ist oft begrenzt oder kostspielig. Die vorliegende Dissertation befasst sich mit der Beschreibung des zerstörungsfreien Werkstoffprüfverfahrens mit dem Namen "Lorentzkraft-Wirbelstromprüfung" und dem experimentellen Funktionsnachweis. Das kontaktlose Messverfahren wurde vor Kurzem an der Technischen Universität Ilmenau erfunden und im Rahmen des Graduiertenkollegs 1567 weiterentwickelt. Diese Arbeit fasst die Ergebnisse der Grundlagenforschung im Bereich experimenteller zerstörungsfreier Werkstoffprüfung mittels Lorentzkraft-Wirbelstromprüfung zusammen, ohne den Anspruch zu erheben, unmittelbar industrielle Anwendungen zu ermöglichen. Das Verfahren "Lorentzkraft-Wirbelstromprüfung" bietet durch die Nutzung von magnetischen Gleichfeldern höhere Eindringtiefen als klassische Wirbelstrommessverfahren unter gleichen Einsatzbedingungen, die magnetische Wechselfelder einsetzen. Dies ermöglicht die Detektion von tiefliegenden Defekten innerhalb eines elektrisch leitfähigen nichtferromagnetischen Werkstoffes. Es wird gezeigt, wie Defekte sicher mit der Lorentzkraft-Wirbelstromprüfung erkannt werden (Detektion), wo sie sich befinden (Lokalisation) und bereitet mit der Beschreibung des direkten Problems die Rekonstruktion vor (inverses Problem). Zur Beschreibung des direkten Problems ist es notwendig, zunächst das Verhalten eines bewegten Festkörpers ohne Defekt in Wechselwirkung mit einem Magnetfeld zu beschreiben. Die Einführung eines relativ simplen Prototypmodels soll Grenzen des Verfahrens aufzeigen und gleichzeitig die grundlegenden Gesetzmäßigkeiten erklären. Als Funktionsnachweis werden experimentelle Daten für künstliche Defekte vorgestellt. Eine Beschreibung der Grenzen des Messverfahrens und eine Analyse des Messsignals werden am genutzten Versuchsaufbau durchgeführt und Vorschläge zur Erweiterung des Messbereichs gegeben.
http://www.db-thueringen.de/servlets/DocumentServlet?id=21716
Dry electrodes for electroencephalography. - In: Neurophysiologie clinique, ISSN 1769-7131, Bd. 43 (2013), 1, S. 76-77
http://dx.doi.org/10.1016/j.neucli.2012.11.028
An approach to the dynamics of a vibration-driven robot. - In: Romansy 19 - robot design, dynamics and control, ISBN 978-3-7091-1378-3, (2013), S. 299-306
Dynamics of two interconnected mass points in a resistive medium. - In: Differential equations and dynamical systems, ISSN 0974-6870, Bd. 21 (2013), 1/2, S. 21-28
The problem of motion of two interconnected points in a resistive medium under periodic change of distance between them is considered. It is shown that a necessary condition for the locomotion (displacement of the center of mass) is the nonlinear law of resistance (dry or nonlinear viscous friction). If the mass points are identical, any periodic control law leads to a displacement of the center of mass only in the presence of anisotropic (asymmetrical) friction. If there are different masses, motion is possible also with isotropic friction law under the action of a periodic control law. In the paper such special laws for the control of the velocity and the direction of motion are presented. The friction is assumed to be small and the investigations are based on the method of averaging. By means of this method analytical dependence of the velocity of motion is obtained.
http://dx.doi.org/10.1007/s12591-012-0116-8
Adaptive control of singularly perturbed worm-like locomotion systems. - In: Differential equations and dynamical systems, ISSN 0974-6870, Bd. 21 (2013), 1/2, S. 59-69
We consider a certain type of a worm-like locomotion system: a three mass point system. We assume that this worm is towing a payload, so the masses differ extremely, and we have to deal with a singularly perturbed system. The dynamics equations are coupled via a small parameter $\varepsilon$, which is typical for singularly perturbed systems. In order to apply simple adaptive feedback mechanisms (to approach desired properties of the worm motion) we have to guarantee the minimum-phase property (among others) of such systems. We show that such properties are preserved under singular perturbation. This is done within a general system class via construction of a normal form to gain deeper insight and to analyze such systems. We present the general case and apply the basic transformations to the worm equations. We point out that we are able to classify all required assumptions and properties by system qualities as, e.g., zeros of the reduced model or boundary-layer system. This is in contrast to other authors.
http://dx.doi.org/10.1007/s12591-012-0123-9
Intelligent rotational direction control of passive robotic joint with embedded sensors. - In: Expert systems with applications, Bd. 40 (2013), 4, S. 1265-1273
Passive compliant joints with springs and dampers ensure a smooth contact with the surroundings, especially if robots are in contact with humans, but the passive compliant joints cannot determine precisely the position of the members of the joint or direction of the collision force. In this paper was proposed the structure of a passive compliant robotic joint with conductive silicone rubber elements as internal embedded sensors. The sensors can operate as absorbers of excessive external collision force instead of springs and dampers and can be used for some measurements. Therefore, this joint presents one type of safe robotic mechanisms with an internally measuring system. The sensors were made by press-curing from carbon-black filled silicone rubber which is an electro active material. Various compression tests of the sensors were done. The main task of this study is to investigate the application of a control algorithm for detecting the direction of the robotic joint angular rotation when subjected to an external collision force. Soft computing methodology, adaptive neuro fuzzy inference strategy (ANFIS), was used for the controller development. The simulation results presented in this paper show the effectiveness of the developed method.
http://dx.doi.org/10.1016/j.eswa.2012.08.064
Generation and shift of gaits in biomorphic systems. - In: Proceedings, ISBN 978-954-20-0550-6, (2012), S. 94-100