Embryonic biopsy routinely involves the removal of one or two blastomeres in the preimplantation genetic diagnosis (PGD) procedure to determine the presence of a specific disease. The rapid development of the PGD technique and stem cell research has led to great demand for highly automated high precision equipment for cellular component micro-extraction. This thesis presents the development of an automated microsurgery system for embryo biopsy. While the ultimate objective of this research is to improve the so called “take-home-baby rate”, the primary focus of this research, however, is devoted to demonstrate the automation of the first two steps in the embryo biopsy procedure: embryo immobilization and embryo perforation with a piezoelectric actuated micro-cutter mounted on a five DOF micromanipulator. A biological embryo holding device incorporating a unique configuration of fluidic channels is designed to increase embryo mobility in order to overcome friction force while maintaining a low suction flow rate and pressure. The validity of this design is demonstrated by good qualitative agreement between the experimental and simulation results. 3D nonlinear equations of motion of a micro-needle driven longitudinally by a piezoelectric actuator are developed based on Kane’s method . The longitudinal vibration of a micro-needle results in excitation of its out-of-plane, lateral eigenmodes at low damping coefficients. The dynamic model is in good agreement with experimental observations. This model is exploited further to describe the response of an immersed glass micropipette with imbedded mercury in piezo-assisted intracytoplasmic sperm injection (ICSI). Furthermore, piezoelectric actuator dynamic nonlinearity introduced by hysteresis is addressed in this research. A new model is proposed to characterize the rate-dependent hysteresis based on Duffing's equation. A nonlinear capacitor element is incorporated into a linear second-order system to predict the relationship between an input state and a hysteretic output. The proposed hysteresis model is verified experimentally. Based on this approach, a new electromechanical piezoelectric actuator model is proposed. A vision-assisted controller for embryo perforation is proposed by implementing a vision tracking and robust autofocusing algorithm using the particle swarm optimization (PSO) method. The performance of the proposed visual-based controller demonstrated experimentally to be effective in providing accurate embryo and micro-needle 3D positioning. Finally, an automated embryo perforation with the proposed mechanical approach was conducted successfully.

Embryonic biopsy routinely involves the removal of one or two blastomeres in the preimplantation genetic diagnosis (PGD) procedure to determine the presence of a specific disease. The rapid development of the PGD technique and stem cell research has led to great demand for highly automated high precision equipment for cellular component micro-extraction. This thesis presents the development of an automated microsurgery system for embryo biopsy. While the ultimate objective of this research is to improve the so called “take-home-baby rate”, the primary focus of this research, however, is devoted to demonstrate the automation of the first two steps in the embryo biopsy procedure: embryo immobilization and embryo perforation with a piezoelectric actuated micro-cutter mounted on a five DOF micromanipulator. A biological embryo holding device incorporating a unique configuration of fluidic channels is designed to increase embryo mobility in order to overcome friction force while maintaining a low suction flow rate and pressure. The validity of this design is demonstrated by good qualitative agreement between the experimental and simulation results. 3D nonlinear equations of motion of a micro-needle driven longitudinally by a piezoelectric actuator are developed based on Kane’s method . The longitudinal vibration of a micro-needle results in excitation of its out-of-plane, lateral eigenmodes at low damping coefficients. The dynamic model is in good agreement with experimental observations. This model is exploited further to describe the response of an immersed glass micropipette with imbedded mercury in piezo-assisted intracytoplasmic sperm injection (ICSI). Furthermore, piezoelectric actuator dynamic nonlinearity introduced by hysteresis is addressed in this research. A new model is proposed to characterize the rate-dependent hysteresis based on Duffing's equation. A nonlinear capacitor element is incorporated into a linear second-order system to predict the relationship between an input state and a hysteretic output. The proposed hysteresis model is verified experimentally. Based on this approach, a new electromechanical piezoelectric actuator model is proposed. A vision-assisted controller for embryo perforation is proposed by implementing a vision tracking and robust autofocusing algorithm using the particle swarm optimization (PSO) method. The performance of the proposed visual-based controller demonstrated experimentally to be effective in providing accurate embryo and micro-needle 3D positioning. Finally, an automated embryo perforation with the proposed mechanical approach was conducted successfully.

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In this thesis, several aspects of GPR data processing for RC bridge decks are studied. First, autofocusing techniques are proposed to replace the previous expensive and unreliable human visual inspections during the iterative migration process for the estimation of the velocity/dielectric permittivity distribution from GPR data. Second, F-K filtering with dip relaxation is proposed for interference removal that is important for both imaging and the performance of post-processing techniques including autofocusing techniques and CS-based migration studied in this thesis. The targeted interferes here are direct waves and cross rebar reflections. The introduced dip relaxation is for accommodating surface roughness and medium inhomogeneity. Third, the newly developed CS-based migration is modified and evaluated on GPR data from RC bridge decks. A more accurate model by accounting for impulse waveform distortion that leads to less modeling errors is proposed. The impact of the selection of the regularization parameter on the comparative amplitude reservation and the imaging performance is also investigated, and an approach to preserve the comparative amplitude information while still maintaining a clear image is proposed. Moreover, the potential of initially sampling the time-spatial data with uniform sampling rates lower than that required by traditional migration methods is evaluated.

Dans le circuit de la greffe de cornée, l'endothélium de chaque greffon est observé en microscopie optique conventionnelle afin de vérifier que sa densité cellulaire est suffisante pour maintenir une bonne transparence après l'opération. Les greffons étant conservés dans un milieu spécifique, ils sont imprégnés de liquide et présentent donc des plis qui perturbent l'observation et le comptage des cellules. Ce problème pratique est à l'origine d’une étude théorique sur les concepts de profondeur de champ étendue et de shape-from-focus. A partir d'une séquence d'images acquise par sectionnement optique, les informations les plus nettes permettent d'une part d'accéder à la topographie de la surface observée et d'autre part de restaurer l'image de sa texture. Une reconstruction surfacique 3-D est alors obtenue en projetant la texture sur la topographie. Cette thèse considère essentiellement l’étape fondamentale de mesure de netteté du processus de reconstruction. Des nouvelles mesures génériques offrant une haute sensibilité à la netteté sont introduites. De par une stratégie 3-D originale au travers de la séquence d'images, une autre mesure très robuste au bruit est proposée. Toutes ces mesures sont testées sur des données simulées puis diverses acquisitions réelles en microscopie optique conventionnelle et comparées aux méthodes de la littérature. Par ailleurs, la mesure 3-D améliore nettement les reconstructions d'endothéliums cornéens à partir de leurs acquisitions particulièrement perturbées (inversions de contraste). Un processus itératif complet de reconstruction 3-D d’endothéliums cornéens est finalement décrit, aboutissant à des résultats solides et exploitables. / In the cornea transplant process, each graft endothelium is observed by conventional optical microscopy to check that its cell density is sufficient to maintain a proper transparency after the transplantation. The grafts are stored in a specific preservation medium, they are thus impregnated with fluid and therefore exhibit folds which make cell observation and counting difficult. This practical issue led to the following theoretical study about the so-called concepts: extended-depth-of-field and shape-from-focus. Throughout a sequence of images acquired by optical sectioning, the in-focus information allows on the one hand to recover the topography of the observed surface and on the other hand to restore the image of its texture. A 3-D reconstruction is then obtained by mapping the texture onto the topography. This thesis basically considers the fundamental step of the reconstruction process that is the focus measurement. New generic focus measurements exhibiting high sharpness sensitivity are introduced. Another one offering high noise robustness is proposed, due to an original 3-D strategy through the image sequence, unlike traditional methods that operate in 2-D. All of them are tested on simulated data and various real acquisitions, and compared to the state-of-the-art methods. Furthermore, the aforementioned 3-D focus measurement clearly improves the 3-D surface reconstructions of the corneal endotheliums from their particularly disturbed acquisitions (contrast reversals). A complete iterative process of 3-D reconstruction of the corneal endothelial surfaces is finally described, resulting in solid results that can already be transferred to cornea banks.