Modélisation de la précision micrométrique des robots manipulateurs pilotés à l'aide d'informations extéroceptives

L'auteur propose une modélisation stochastique de la précision des robots manipulateurs lorsqu'il est possible d'acquérir des informations dans un repère local à l'aide de capteurs à résolution micrométrique. Dans cette configuration, il est démontré que ni la répétabilité, ni l'exactitude de pose ne permettent d'évaluer l'erreur finale de positionnement et que dans certains cas, il est possible de positionner le robot avec une erreur finale inférieure à la valeur de la répétabilité. Des résultats expérimentaux sont présentés à l'appui de cette modélisation

Development of a Fabrication Technique for Soft Planar Inflatable Composites

Soft robotics is a rapidly growing field in robotics that combines aspects of biologically inspired characteristics to unorthodox methods capable of conforming and/or adapting to unknown tasks or environments that would otherwise be improbable or complex with conventional robotic technologies. The field of soft robotics has grown rapidly over the past decade with increasing popularity and relevance to real-world applications. However, the means of fabricating these soft, compliant and intricate robots still poses a fundamental challenge, due to the liberal use of soft materials that are difficult to manipulate in their original state such as elastomers and fabric. These material properties rely on informal design approaches and bespoke fabrication methods to build soft systems. As such, there are a limited variety of fabrication techniques used to develop soft robots which hinders the scalability of robots and the time to manufacture, thus limiting their development. This research focuses towards developing a novel fabrication method for constructing soft planar inflatable composites. The fundamental method is based on a sub-set of additive manufacturing known as composite layering. The approach is designed from a planar manner and takes layers of elastomeric materials, embedded strain-limiting and mask layers. These components are then built up through a layer-by-layer fabrication method with the use of a bespoke film applicator set-up. This enables the fabrication of millimetre-scale soft inflatable composites with complex integrated masks and/or strain-limiting layers. These inflatable composites can then be cut into a desired shape via laser cutting or ablation. A design approach was also developed to expand the functionality of these inflatable composites through modelling and simulation via finite element analysis. Proof of concept prototypes were designed and fabricated to enable pneumatic driven actuation in the form of bending soft actuators, adjustable stiffness sensor, and planar shape change. This technique highlights the feasibility of the fabrication method and the value of its use in creating multi-material composite soft actuators which are thin, compact, flexible, and stretchable and can be applicable towards real-world application

Techniques, Circuits and Devices for Noncontact Sensing through Wireless Coupling

Le tecnologie per la misurazione di grandezze fisiche senza contatto sono diventate sempre più centrali in vari settori, che vanno dal monitoraggio industriale alle applicazioni sanitarie. In questo contesto, la tesi si concentra sullo sviluppo e l'implementazione di tecniche innovative, circuiti elettronici e dispositivi per la rilevazione senza contatto. L’analisi presentata all'interno di questa tesi considera lo scenario del rilevamento senza contatto a distanza nel campo elettromagnetico lontano (far-field) e al rilevamento senza contatto di prossimità, sfruttando le interazioni elettromagnetiche in campo vicino (near field). Nell’ambito del rilevamento senza contatto a distanza, la tesi indaga l'uso delle onde elettromagnetiche per il monitoraggio non invasivo del livello di solidi granulari all’interno di silos. Questo sistema, sviluppato impiegando un sensore radar commerciale a onda continua modulata in frequenza, dimostra il potenziale di questa tecnologia nel monitoraggio non invasivo e senza contatto in contesti agricoli e industriali. Considerando invece lo scenario del rilevamento senza contatto di prossimità, la tesi fornisce un'analisi dell'interrogazione senza contatto di sensori passivi e ne presenta diversi approcci e applicazioni. Vengono affrontate le problematiche delle misurazioni senza contatto, proponendo alcune soluzioni per migliorarne l'affidabilità e l'accuratezza, permettendo in particolare di renderle indipendenti dalla distanza di interrogazione. In particolare, la tesi presenta un sistema per la misurazione senza contatto della frequenza di risonanza di risonatori MEMS piezoelettrici. La tecnica proposta sfrutta l'accoppiamento magnetico tra un’unità di interrogazione ed un’unità sensore ed è applicata in modo innovativo per la rilevazione della temperatura, sfruttando le proprietà dei risonatori a disco in nitruro di alluminio (AlN) su silicio sottile piezoelettrico (TPoS) ed una tecnica di interrogazione senza contatto a tempo commutato. Inoltre, la tesi presenta un’etichetta flessibile per la misurazione della temperatura corporea, che combina il rilevamento a contatto della temperatura con una lettura senza contatto dell’unità sensore sfruttandone l'accoppiamento magnetico con un unità di interrogazione. L’etichetta flessibile, che costituisce l'unità sensore, è composta da una bobina induttiva che consente l'accoppiamento magnetico, un condensatore ceramico utilizzato come elemento sensibile alla temperatura, sfruttandone il coefficiente di temperatura della capacità, ed un induttore aggiuntivo utilizzato per rendere la frequenza di risonanza del circuito risonante RLC indipendente dalla flessione dell’etichetta. In modo analogo, le tecniche di interrogazione proposte sono state applicate ad un nuovo metodo per l'interrogazione senza contatto di un sensore induttivo, utilizzato per rilevare target conduttivi. Il sistema proposto presenta una bobina avvolta collegata con un condensatore per formare un circuito LC risonante, la cui frequenza di risonanza cambia quando un target conduttivo viene introdotto nel campo magnetico generato dalla bobina stessa. Attraverso una bobina di interrogazione esterna, accoppiata elettromagneticamente al sensore induttivo, è possibile interrogare senza contatto il sensore induttivo, permettendo quindi la rilevazione a distanza di target conduttivi. Infine, lo studio esposto in questa tesi introduce una tecnica avanzata per l'interrogazione senza contatto di sensori resistivi passivi, sfruttando risonatori a cristallo di quarzo come dispositivo risonante e basandosi sulla stima del fattore di qualità del circuito che costituisce l’unità sensore. Il metodo proposto supera i limiti delle tecniche basate su misure di ampiezza, legati in particolare all'influenza della distanza di interrogazioneNoncontact sensing technologies have become increasingly central in a variety of fields, ranging from industrial monitoring to healthcare applications. In this context, the thesis focuses on the development and implementation of innovative techniques, electronic circuits, and devices for contactless sensing via wireless coupling, responding to the growing interest in noncontact measurement methods. The themes treated in this thesis regard both the scenario of distant noncontact sensing in the electromagnetic far field, and proximate wireless sensing, leveraging on near-field electromagnetic interactions. Each domain is distinctly characterized by its specific technologies, applications, and methodologies, reflecting their operational ranges and fundamental principles. In the domain of distant wireless sensing, the thesis investigates the use of electromagnetic waves for unobtrusive level monitoring of granular solids in silos. This system, developed employing a commercial frequency-modulated continuous-wave radar sensor, demonstrates the potential of this technology in unobtrusive monitoring in agricultural and industrial environments. Considering the proximate wireless sensing domain, the thesis provides an analysis of noncontact interrogation of passive sensors and it presents different approaches and applications. It addresses the challenges and offers solutions for enhancing the reliability and accuracy of contactless measurements, which can be advantageously independent of the interrogation distance. This can path the way to the development of low-cost, disposable and sustainable devices for healthcare and industrial applications. In particular, the thesis presents a system for the noncontact measurement of the resonant frequency of piezoelectric MEMS resonators. The technique exploits magnetic coupling between interrogation and sensor units, and it is innovatively applied for temperature sensing exploiting a thin-film piezoelectric on silicon (TPoS) aluminium nitride (AlN) disk resonators and a contactless interrogation time-gated technique. Furthermore, the thesis presents a flexible patch for body temperature measurement, combining contact sensing with contactless readout, and exploiting magnetic coupling between interrogation and sensor units. The flexible patch, forming the sensor unit, is composed of an inductive coil for magnetic coupling, a ceramic capacitor used as the temperature sensing element exploiting its temperature coefficient of capacitance and an additional inductor to make the resonant frequency of the resulting resonant RLC circuit independent from the bending of the patch. Similarly, interrogation techniques have been applied to a novel method for contactless interrogation of an inductive sensor used for detecting conductive targets. The system features a solenoidal coil connected with a capacitor to form a resonating LC circuit, whose resonant frequency changes when a conductive target is introduced in the generated magnetic field. An external interrogation coil electromagnetically coupled to the inductive sensor enables the wireless measurement for conductive target detection. Lastly, the study introduces an advanced technique for the contactless interrogation of passive resistive sensors. The novel approach exploits the resonant frequency stability and the high quality factor of a quartz crystal resonator, used as a resonant element, with a series-connected resistor acting as the sensing element. This method overcomes the limitations of amplitude measurements techniques typically affected by the interrogation distance

Monitoring bioinspired fibrillar grippers by contact observation and machine learning

The remarkable properties of bio-inspired microstructures make them extensively accessible for various applications, including industrial, medical, and space applications. However, their implementation especially as grippers for pick-and-place robotics can be compromised by multiple factors. The most common ones are alignment imperfections with the target object, unbalanced stress distribution, contamination, defects, and roughness at the gripping interface. In the present work, three different approaches to assess the contact phenomena between patterned structures and the target object are presented. First, in-situ observation and machine learning are combined to realize accurate real-time predictions of adhesion performance. The trained supervised learning models successfully predict the adhesion performance from the contact signature. Second, two newly developed optical systems are compared to observe the correct grasping of various target objects (rough or transparent) by looking through the microstructures. And last, model experiments are provided for a direct comparison with simulation efforts aiming at a prediction of the contact signature and an analysis of the rate and preload-dependency of the adhesion strength of a soft polymer film in contact with roughness-like surface topography. The results of this thesis open new perspectives for improving the reliability of handling systems using bioinspired microstructures.Durch die besonderen Eigenschaften bioinspirierter Mikrostrukturen können diese für verschiedene Anwendungen genutzt werden, einschließlich industrieller, medizinischer und Weltraumanwendungen. Ihre Implementierung, insbesondere als Greifer für Pick-and-Place-Robotiker, kann jedoch durch mehrere Faktoren beeinträchtigt werden. Am häufigsten sind Ausrichtungsmängel an das Zielobjekt, unausgeglichene Spannungsverteilungen, Defekte und Rauheit an der Greifschnittstelle. Die vorliegende Arbeit zeigt drei verschiedene Ansätze, um den Kontakt zwischen strukturierten Adhäsiven und Zielobjekten zu untersuchen. Zunächst werden in-situ Beobachtungen und maschinelles Lernen kombiniert, um Echtzeitvorhersagen der Adhäsionsleistung zu ermöglichen. Die trainierten Modelle werden verwendet, um die Haftungsleistung anhand der Kontaktsignatur des Pads erfolgreich zu prognostizieren. Anschließend werden zwei neu entwickelte, optische Systeme verglichen, mit denen das korrekte ” Greifen“ von verschiedenen Objekten (mit rauen oder undurchsichtigen Oberflächen) durch die Mikrostrukturen live verfolgt werden kann. Zuletzt werden Modellexperimente durchgeführt, die mit Simulationen der Signatur des Kontakts einer weichen Polymerschicht mit einer idealisierten rauen Gegenfläche direkt verglichen werden können. Die Ergebnisse dieser Arbeit eröffnen neue Perspektiven zur zuverlässigeren Verwendung von Handhabungssystemen mit bioinspirierten Mikrostrukturen.Leibniz Competition Grant MUSIGAND (No. K279/2019) awarded to Eduard Arz

Flexible Automation and Intelligent Manufacturing: The Human-Data-Technology Nexus

This is an open access book. It gathers the first volume of the proceedings of the 31st edition of the International Conference on Flexible Automation and Intelligent Manufacturing, FAIM 2022, held on June 19 – 23, 2022, in Detroit, Michigan, USA. Covering four thematic areas including Manufacturing Processes, Machine Tools, Manufacturing Systems, and Enabling Technologies, it reports on advanced manufacturing processes, and innovative materials for 3D printing, applications of machine learning, artificial intelligence and mixed reality in various production sectors, as well as important issues in human-robot collaboration, including methods for improving safety. Contributions also cover strategies to improve quality control, supply chain management and training in the manufacturing industry, and methods supporting circular supply chain and sustainable manufacturing. All in all, this book provides academicians, engineers and professionals with extensive information on both scientific and industrial advances in the converging fields of manufacturing, production, and automation

Factories of the Future

Engineering; Industrial engineering; Production engineerin

DEVELOPMENT OF FUNCTIONAL NANOCOMPOSITE MATERIALS TOWARDS BIODEGRADABLE SOFT ROBOTICS AND FLEXIBLE ELECTRONICS

World population is continuously growing, as well as the influence we have on the ecosystem\u2019s natural equilibrium. Moreover, such growth is not homogeneous and it results in an overall increase of older people. Humanity\u2019s activity, growth and aging leads to many challenging issues to address: among them, there are the spread of suddenly and/or chronic diseases, malnutrition, resource pressure and environmental pollution. Research in the novel field of biodegradable soft robotics and electronics can help dealing with these issues. In fact, to face the aging of the population, it is necessary an improvement in rehabilitation technologies, physiological and continuous monitoring, as well as personalized care and therapy. Also in the agricultural sector, an accurate and efficient direct measure of the plants health conditions would be of help especially in the less-developed countries. But since living beings, such as humans and plants, are constituted by soft tissues that continuously change their size and shapes, today\u2019s traditional technologies, based on rigid materials, may not be able to provide an efficient interaction necessary to satisfy these needs: the mechanical mismatch is too prohibitive. Instead, soft robotic systems and devices can be designed to combine active functionalities with soft mechanical properties that can allow them to efficiently and safely interact with soft living tissues. Soft implantable biomedical devices, smart rehabilitation devices and compliant sensors for plants are all applications that can be achieved with soft technologies. The development of sophisticated autonomous soft systems needs the integration on a unique soft body or platform of many functionalities (such as mechanical actuation, energy harvesting, storage and delivery, sensing capabilities). A great research interest is recently arising on this topic, but yet not so many groups are focusing their efforts in the use of natural-derived and biodegradable raw materials. In fact, resource pressure and environmental pollution are becoming more and more critical problems. It should be completely avoided the use of in exhaustion, pollutant, toxic and non-degradable resources, such as lithium, petroleum derivatives, halogenated compounds and organic solvents. So-obtained biodegradable soft systems and devices could then be manufactured in high number and deployed in the environment to fulfil their duties without the need to recover them, since they can safely degrade in the environment. The aim of the current Ph.D. project is the use of natural-derived and biodegradable polymers and substances as building blocks for the development of smart composite materials that could operate as functional elements in a soft robotic system or device. Soft mechanical properties and electronic/ionic conductive properties are here combined together within smart nanocomposite materials. The use of supersonic cluster beam deposition (SCBD) technique enabled the fabrication of cluster-assembled Au electrodes that can partially penetrate into the surface of soft materials, providing an efficient solution to the challenge of coupling conductive metallic layers and soft deformable polymeric substrates. In this work, cellulose derivatives and poly(3-hydroxybutyrate) bioplastic are used as building blocks for the development of both underwater and in-air soft electromechanical actuators that are characterized and tested. A cellulosic matrix is blended with natural-derived ionic liquids to design and manufacture completely biodegradable supercapacitors, extremely interesting energy storage devices. Lastly, ultrathin Au electrodes are here deposited on biodegradable cellulose acetate sheets, in order to develop transparent flexible electronics as well as bidirectional resistive-type strain sensors. The results obtained in this work can be regarded as a preliminary study towards the realization of full natural-derived and biodegradable soft robotic and electronic systems and devices

Flexible Automation and Intelligent Manufacturing: The Human-Data-Technology Nexus

This is an open access book. It gathers the first volume of the proceedings of the 31st edition of the International Conference on Flexible Automation and Intelligent Manufacturing, FAIM 2022, held on June 19 – 23, 2022, in Detroit, Michigan, USA. Covering four thematic areas including Manufacturing Processes, Machine Tools, Manufacturing Systems, and Enabling Technologies, it reports on advanced manufacturing processes, and innovative materials for 3D printing, applications of machine learning, artificial intelligence and mixed reality in various production sectors, as well as important issues in human-robot collaboration, including methods for improving safety. Contributions also cover strategies to improve quality control, supply chain management and training in the manufacturing industry, and methods supporting circular supply chain and sustainable manufacturing. All in all, this book provides academicians, engineers and professionals with extensive information on both scientific and industrial advances in the converging fields of manufacturing, production, and automation