Learning, Moving, And Predicting With Global Motion Representations

In order to effectively respond to and influence the world they inhabit, animals and other intelligent agents must understand and predict the state of the world and its dynamics. An agent that can characterize how the world moves is better equipped to engage it. Current methods of motion computation rely on local representations of motion (such as optical flow) or simple, rigid global representations (such as camera motion). These methods are useful, but they are difficult to estimate reliably and limited in their applicability to real-world settings, where agents frequently must reason about complex, highly nonrigid motion over long time horizons. In this dissertation, I present methods developed with the goal of building more flexible and powerful notions of motion needed by agents facing the challenges of a dynamic, nonrigid world. This work is organized around a view of motion as a global phenomenon that is not adequately addressed by local or low-level descriptions, but that is best understood when analyzed at the level of whole images and scenes. I develop methods to: (i) robustly estimate camera motion from noisy optical flow estimates by exploiting the global, statistical relationship between the optical flow field and camera motion under projective geometry; (ii) learn representations of visual motion directly from unlabeled image sequences using learning rules derived from a formulation of image transformation in terms of its group properties; (iii) predict future frames of a video by learning a joint representation of the instantaneous state of the visual world and its motion, using a view of motion as transformations of world state. I situate this work in the broader context of ongoing computational and biological investigations into the problem of estimating motion for intelligent perception and action

Construction of camera motion with Pitagorean curves

V delu obravnavamo konstrukcije gibanja kamere okoli fiksnega objekta. Želimo si, da so gibanja opisana z racionalnimi krivuljami. Predstavljeno je, kako to naredimo z uporabo P-krivulj in kvaternionov. Opisani so Bernsteinovi bazni polinomi, pomen kontrolnih točk ter kontrolnega poligona in primerjava zapisa krivulje v Bernsteinovi bazi in standardni bazi. Definirana so prikrojena in usmerjena ogrodja ter razlika med njimi, opisana pa so tudi rotacijsko minimizirajoča ogrodja in pogoji za njihovo konstrukcijo. V zaključku je predstavljen preprost interpolacijski problem za konstrukcijo P-krivulje, ki interpolira začetno in končno točko in se jo da opremiti z rotacijsko minimizirajočim usmerjenim ogrodjem. Rezultati so prikazani na več numeričnih primerih.The present thesis deals with the construction of camera movements around a fixed object. The movements are described by means of rational curves. The thesis presents how that is performed by using P-curves and quaternions. It describes Bernstein basis polynomials, the meaning of control points and the control polygon, and also the comparison of curve representation in Bernstein basis and in standard basis. Adapted and directed frames are defined as well as the difference between them. In addition, rotation minimizing frames and the conditions for their constructions are described. In conclusion, a simple interpolation problem of a P-curve construction is presented, which interpolates the first and the last point and can be equipped with a rotation minimizing directed frame. The results are shown in several numerical examples

Applying BAT Evolutionary Optimization to Image-Based Visual Servoing

This paper presents a predictive control strategy for an image-based visual servoing scheme that employs evolutionary optimization. The visual control task is approached as a nonlinear optimization problem that naturally handles relevant visual servoing constraints such as workspace limitations and visibility restrictions. As the predictive scheme requires a reliable model, this paper uses a local model that is based on the visual interaction matrix and a global model that employs 3D trajectory data extracted from a quaternion-based interpolator. The work assumes a free-flying camera with 6-DOF simulation whose results support the discussion on the constraint handling and the image prediction scheme

Humanoid Robots

For many years, the human being has been trying, in all ways, to recreate the complex mechanisms that form the human body. Such task is extremely complicated and the results are not totally satisfactory. However, with increasing technological advances based on theoretical and experimental researches, man gets, in a way, to copy or to imitate some systems of the human body. These researches not only intended to create humanoid robots, great part of them constituting autonomous systems, but also, in some way, to offer a higher knowledge of the systems that form the human body, objectifying possible applications in the technology of rehabilitation of human beings, gathering in a whole studies related not only to Robotics, but also to Biomechanics, Biomimmetics, Cybernetics, among other areas. This book presents a series of researches inspired by this ideal, carried through by various researchers worldwide, looking for to analyze and to discuss diverse subjects related to humanoid robots. The presented contributions explore aspects about robotic hands, learning, language, vision and locomotion

Multidimensional Wavelets and Computer Vision

This report deals with the construction and the mathematical analysis of multidimensional nonseparable wavelets and their efficient application in computer vision. In the first part, the fundamental principles and ideas of multidimensional wavelet filter design such as the question for the existence of good scaling matrices and sensible design criteria are presented and extended in various directions. Afterwards, the analytical properties of these wavelets are investigated in some detail. It will turn out that they are especially well-suited to represent (discretized) data as well as large classes of operators in a sparse form - a property that directly yields efficient numerical algorithms. The final part of this work is dedicated to the application of the developed methods to the typical computer vision problems of nonlinear image regularization and the computation of optical flow in image sequences. It is demonstrated how the wavelet framework leads to stable and reliable results for these problems of generally ill-posed nature. Furthermore, all the algorithms are of order O(n) leading to fast processing

Virtuaalse proovikabiini 3D kehakujude ja roboti juhtimisalgoritmide uurimine

Väitekirja elektrooniline versioon ei sisalda publikatsiooneVirtuaalne riiete proovimine on üks põhilistest teenustest, mille pakkumine võib suurendada rõivapoodide edukust, sest tänu sellele lahendusele väheneb füüsilise töö vajadus proovimise faasis ning riiete proovimine muutub kasutaja jaoks mugavamaks. Samas pole enamikel varem välja pakutud masinnägemise ja graafika meetoditel õnnestunud inimkeha realistlik modelleerimine, eriti terve keha 3D modelleerimine, mis vajab suurt kogust andmeid ja palju arvutuslikku ressurssi. Varasemad katsed on ebaõnnestunud põhiliselt seetõttu, et ei ole suudetud korralikult arvesse võtta samaaegseid muutusi keha pinnal. Lisaks pole varasemad meetodid enamasti suutnud kujutiste liikumisi realistlikult reaalajas visualiseerida. Käesolev projekt kavatseb kõrvaldada eelmainitud puudused nii, et rahuldada virtuaalse proovikabiini vajadusi. Välja pakutud meetod seisneb nii kasutaja keha kui ka riiete skaneerimises, analüüsimises, modelleerimises, mõõtmete arvutamises, orientiiride paigutamises, mannekeenidelt võetud 3D visuaalsete andmete segmenteerimises ning riiete mudeli paigutamises ja visualiseerimises kasutaja kehal. Selle projekti käigus koguti visuaalseid andmeid kasutades 3D laserskannerit ja Kinecti optilist kaamerat ning koostati nendest andmebaas. Neid andmeid kasutati välja töötatud algoritmide testimiseks, mis peamiselt tegelevad riiete realistliku visuaalse kujutamisega inimkehal ja suuruse pakkumise süsteemi täiendamisega virtuaalse proovikabiini kontekstis.Virtual fitting constitutes a fundamental element of the developments expected to rise the commercial prosperity of online garment retailers to a new level, as it is expected to reduce the load of the manual labor and physical efforts required. Nevertheless, most of the previously proposed computer vision and graphics methods have failed to accurately and realistically model the human body, especially, when it comes to the 3D modeling of the whole human body. The failure is largely related to the huge data and calculations required, which in reality is caused mainly by inability to properly account for the simultaneous variations in the body surface. In addition, most of the foregoing techniques cannot render realistic movement representations in real-time. This project intends to overcome the aforementioned shortcomings so as to satisfy the requirements of a virtual fitting room. The proposed methodology consists in scanning and performing some specific analyses of both the user's body and the prospective garment to be virtually fitted, modeling, extracting measurements and assigning reference points on them, and segmenting the 3D visual data imported from the mannequins. Finally, superimposing, adopting and depicting the resulting garment model on the user's body. The project is intended to gather sufficient amounts of visual data using a 3D laser scanner and the Kinect optical camera, to manage it in form of a usable database, in order to experimentally implement the algorithms devised. The latter will provide a realistic visual representation of the garment on the body, and enhance the size-advisor system in the context of the virtual fitting room under study

KRISTINA: Kinematic RIb based STructural system for INnovative Adaptive trailing edges

L’obiettivo principale della Tesi di Dottorato, dal titolo "KRISTINA, Kinematic RIb based STructural system for INnovative Adaptive trailing edges", è stato quello di progettare, da un punto di vista strutturale, un bordo d’uscita alare adattivo, nell’ambito del progetto FP7 SARISTU. In particolare, l’implementazione della variazione della curvatura è stata realizzata attraverso la progettazione di centine articolate ad un singolo grado di libertà, integrate in una struttura dimensionata per sostenere le condizioni di carico limite di un velivolo della categoria CS 25. Particolare attenzione è stata posta nella verifica strutturale e funzionale, nonché nell’accertamento della rispondenza delle geometrie realizzate rispetto a quelle teoriche. Approcci sia teorici che sperimentali sono stati impiegati nella validazione del design. Ogni anno i trasferimenti aerei vengono utilizzati da oltre tre miliardi di persone nel mondo e per trasportare migliaia di miliardi di euro di beni. Questi valori sono in crescita secondo le statistiche e potrebbero raddoppiare entro pochi lustri. Con la crescita del numero dei voli, le sfide per l’industria aeronautica sono rappresentate dalla realizzazione di velivoli sempre più leggeri, più efficienti, in grado di mantenere bassi costi operativi e ridurre l’impatto ambientale in termini di inquinamento e rumore. In questo scenario, le strutture adattive sono state individuate dai ricercatori come un potenziale strumento per il raggiungimento di queste finalità, principalmente grazie ai vantaggi che un velivolo, in prospettiva totalmente adattabile alle diverse condizioni di volo, presenterebbe in termini di miglioramento delle prestazioni aerodinamiche e conseguentemente nell’ottimizzazione dei consumi. Nell’ambito del progetto SARISTU, il più grande progetto di ricerca finanziato dall’Unione Europea, è stata trattata l’integrazione fisica di strutture “intelligenti” sull’ala di un velivolo da trasporto civile, ed in particolare di un bordo d’uscita, un bordo d’attacco ed una winglet morphing. Nel presente lavoro di tesi è stato sviluppato il design della struttura primaria dell’”Adaptive Trailing Edge Device”, la sua integrazione con i sistemi di controllo e attuazione, la sua verifica strutturale, sia statica che aeroelastica e la validazione del design attraverso innovative tecniche low cost di reverse engineering. Le prove in galleria del vento hanno dimostrato un effettivo impatto, in particolare dell’ATED, sulle prestazioni dell’ala. I principali risultati includono la definizione di una strategia progettuale efficace, sia in fase preliminare che di dettaglio, di un dispositivo morphing ad alto TRL, nonché la dimostrazione della integrabilità di tale tecnologia in strutture reali. Tali risultati hanno ricadute applicative, prefigurando la possibilità di integrazione di un trailing edge adattivo sull’ala di un velivolo reale per la dimostrazione della sua efficacia attraverso prove di volo