This work addresses the problem of localizing an impact in a dispersive medium (waveguide) using a network of vibration sensors (accelerometers), distributed at various locations in the waveguide, measuring (and detecting the arrival of) the impact-generated seismic wave. In particular, the last part of this document focuses on the problem of localizing footsteps using underfloor accelerometers. The author believes the outcomes of this work pave the way for realizing real-time indoor occupant tracking using underfloor accelerometers; a system that is tamper-proof and non-intrusive compared to occupant tracking systems that rely on video image processing. A dispersive waveguide (e.g., a floor) causes the impact-generated wave to distort with the traveled distance and renders conventional time of flight localization methods inaccurate. Therefore, this work focuses on laying the foundation of a new alternative approach to impact localization in dispersive waveguides. In this document, localization algorithms, including wave-signal detection and signal processing, are developed utilizing the fact that the generated wave's energy is attenuated with the traveled distance. The proposed localization algorithms were evaluated using simulations and experiments of hammer impacts, in addition to occupant tracking experiments. The experiments were carried out on an instrumented floor section inside a smart building. As will be explained in this document, energy-based localization will turn out to be computationally cheap and more accurate than conventional time of flight techniques. / PHD

This work demonstrates an application of Vibration-Based Occupant Inference (VBOI) in frailty analysis. The rise of both Internet-of-Things (IoT) and VBOI provide new techniques to perform gait analysis via footstep-induced vibration which can be analyzed for early detection of human frailty. Thus, this work provides an application of VBOI to passively track gait parameters (e.g., gait speed) using floor-mounted accelerometers as opposed to using a manual chronometer as it is commonly performed by healthcare professionals. The first part of this thesis describes the techniques used for footstep detection by measuring the power of the footstep-generated vibration waves. The extraction of temporal gait parameters from consecutive footsteps can then be used to estimate temporal features such as cadence and stride time variation. VBOI provides many algorithms to accurately detect when a human-induced vibration event happened, however, spatial information is also needed for many gait parameters used in frailty diagnosis. Detecting where an event happened is a complicated problem because footsteps waves travel and decay in different ways according to the medium (floor system), the number of people walking, and even the walking speed. Therefore, the second part of this work will utilize an energy-based approach of footstep localization in which it is assumed that footstep waves decay exponentially as they travel across the medium. The results from this approach are then used to calculate spatial and tempo-spatial parameters. The main goal of this study is to understand the applicability of VBOI algorithms in gait analysis for frailty detection in a healthcare setting. / Master of Science / Human frailty is responsible for one of the highest healthcare costs and the death of many people every year. Although anyone suffering from frailty has a higher chance of death, it is particularly dangerous for the elderly population and for those suffering from other comorbidities. Diagnosing frailty is hard because it usually happens slowly over time. However, it has been shown that changes in some walking parameters (such as gait speed) can be an early indication of frailty. Many technologies have been created in order to track gait parameters, many of which either require expensive equipment (e.g., force plates) or the use of wearable devices, which can introduce privacy concerns. It has been proposed in the literature that Vibration-Based Occupant Inference (VBOI) techniques could be used in healthcare applications. Such algorithms measure footstep-induced vibration waves in order to detect and track footsteps. This system can provide several advantages in frailty analysis because of its affordability, ease of use, and little impact on patients' privacy. Therefore, the aim of this study is to understand the applicability of VBOI algorithms in gait analysis for frailty detection to be used in a healthcare setting. This thesis will proceed as follows: 1- The demonstration of an energy-based footstep detection and localization algorithm in VBOI. 2 - The application of such algorithms for gait parameters extraction with simulated frail walkers. 3 - Finally, an analysis of the proposed VBOI techniques for deployment in a real hospital setting.

Title: Dependance of the gait parameters on a stature of an adult Objectives: The main aim of this study is to find out how the gait parameters depends on a stature of an adult. Another aim of this study is to compare these parameters between group of men and group of women. Methods: This thesis is type of descriptive - association research. In the practical part was used method of comparison for locomotion of people. As an objectification method was chosen 3D kinematic analysis of gait, which was performed using the Qualisys. Results: It was found that the dependence on a stature subject to the step length, pelvic rotation, flexion of a front knee, frequency and walking speed. Linear dependence on a stature is not subject to the the angle between femurs and flexion of a back knee. It was also found that the values of parameters which have the highest rate of variability reach a relatively low angular values. These parameters include the angle of rotation of a pelvis and the angle of flexion of a front knee. Opposite qualities shows the angle between femurs, which reaches the highest value, but clearly has the lowest rate of variability. Keywords: gait, footstep lenght, double support, stature

Dans cette thèse nous nous intéressons à deux types d'approches pour la planification de pas pour robots humanoïdes : d'une part les approches discrètes où le robot n'a qu'un nombre fini de pas possibles, et d'autre part les approches où le robot se base sur des zones de faisabilité continues. Nous étudions ces problèmes à la fois du point de vue théorique et pratique. En particulier nous décrivons deux méthodes originales, cohérentes et efficaces pour la planification de pas, l'une dans le cas discret (chapitre 5) et l'autre dans le cas continu (chapitre 6). Nous validons ces méthodes en simulation ainsi qu'avec plusieurs expériences sur le robot HRP-2. / In this thesis we investigate two types of approaches for footstep planning for humanoid robots: on one hand the discrete approaches where the robot has only a finite set of possible steps, and on the other hand the approaches where the robot uses continuous feasibility regions. We study these problems both on a theoretical and practical level. In particular, we describe two original, coherent and efficient methods for footstep planning, one in the discrete case (chapter 5), and one in the continuous case (chapter 6). We validate these methods in simulation and with several experiments on the robot HRP-2.

Cette thèse porte sur la réalisation des tâches avec la locomotion sur des robots humanoïdes. Grâce à leurs nombreux degrés de liberté, ces robots possèdent un très haut niveau de redondance. D’autre part, les humanoïdes sont sous-actionnés dans le sens où la position et l’orientation ne sont pas directement contrôlées par un moteur. Ces deux aspects, le plus souvent étudiés séparément dans la littérature, sont envisagés ici dans un même cadre. En outre, la génération d’un mouvement complexe impliquant à la fois des tâches de manipulation et de locomotion, étudiée habituellement sous l’angle de la planification de mouvement, est abordée ici dans sa composante réactivité temps réel. En divisant le processus d’optimisation en deux étapes, un contrôleur basé sur la notion de pile de tâches permet l’adaptation temps réel des empreintes de pas planifiées dans la première étape. Un module de perception est également conçu pour créer une boucle fermée de perception-décision-action. Cette architecture combinant planification et réactivité est validée sur le robot HRP-2. Deux classes d’expériences sont menées. Dans un cas, le robot doit saisir un objet éloigné, posé sur une table ou sur le sol. Dans l’autre, le robot doit franchir un obstacle. Dans les deux cas, les condition d’exécution sont mises à jour en temps réel pour faire face à la dynamique de l’environnement : changement de position de l’objet à saisir ou de l’obstacle à franchir. / This thesis focuses on realization of tasks with locomotion on humanoid robots. Thanks to their numerous degrees of freedom, humanoid robots possess a very high level of redundancy. On the other hand, humanoids are underactuated in the sense that the position and orientation of the base are not directly controlled by any motor. These two aspects, usually studied separately in manipulation and locomotion research, are unified in a same framework in this thesis and are resolved as one unique problem. Moreover, the generation of a complex movement involving both tasks and footsteps is also improved becomes reactive. By dividing the optimization process into appropriate stages and by feeding directly the intermediate result to a task-based controller, footsteps can be calculated and adapted in real-time to deal with changes in the environment. A perception module is also developed to build a closed perception-decision-action loop. This architecture combining motion planning and reactivity validated on the HRP-2 robot. Two classes of experiments are carried out. In one case the robot has to grasp an object far away at different height level. In the other, the robot has to step over an object on the floor. In both cases, the execution conditions are updated in real-time to deal with the dynamics of the environment: changes in position of the target to be caught or of the obstacle to be stepped over.

Digital forensics is a niche field of study that encompasses such things as extraction, analysis and presentation of digital information, that could be used to produce forensic evidence. There are several companies whose sole specialization is providing technical software solutions to detectives to help them quickly analyze retrieved devices that might contain evidence, instead of having to send the devices to forensic labs. However, there are still many areas that aren’t fully explored within the digital forensics industry, such as using personal health data. A factor that confounds this problem is that there are many different mobile devices running different operating systems and different versions of different applications. This report examines footstep data extraction and visualization on Android. Whether this data could be used as evidence according to law enforcement agencies is also investigated. Following a literature study to gain knowledge of the field of digital forensics, an experiment was conducted to gather data on a device through the Samsung Health application. This data was extracted and converted into a database, which was visualized using a prototype in the form of charts. Finally a technical trainer and former police officer was interviewed regarding whether the prototype could be seen as a proof-of-concept for future implementation among digital forensics solution providers. It was concluded that step data visualized in the form of graphs would be useful as forensic evidence for law enforcement detectives and juries. / Digital forensik är ett studieområde som omfattar extraktion, analys och presentation av digital information, som kan användas för att producera forensiskt bevis. Det finns flera firmor som specialiserar i att utrusta detektiver med mjukvarulösningar som kan analysera enheter som kan innehålla bevis, istället för att skicka enheten till ett forensiskt lab. Det finns dock många områden som inte är helt utforskade inom digital forensik, som användning av personlig hälsodata. En faktor som utökar detta problem är att det finns många olika mobila enheter som kör olika operativsystem med olika versioner av olika applikationer. Denna rapport undersöker fotstegsdata extraktion och visualisering på Android. Om denna data kan användas som bevis av rättsväsende blir också utforskat. Efter en litteraturstudie för att få mer kunskap inom digital forensik, utfördes ett experiment för att samla data på en enhet genom Samsung Health- applikationen. Detta data extraherades och konverterades till en databas, som visualiserades genom en prototyp i form av grafer. Slutligen intervjuades en teknisk tränare och ex-polis för att se om prototypen skulle kunna ses som ett bevis på att digital forensik skulle kunna implementera stöd för fotstegsdata i framtiden. Slutsatsen drogs att stegsdata visualiserat i form av grafer skulle vara användbara som forensiskt bevis för detektiver och juryer.