Analysing multi-person timing in music and movement : event based methods

Accurate timing of movement in the hundreds of milliseconds range is a hallmark of human activities such as music and dance. Its study requires accurate measurement of the times of events (often called responses) based on the movement or acoustic record. This chapter provides a comprehensive over - view of methods developed to capture, process, analyse, and model individual and group timing [...] This chapter is structured in five main sections, as follows. We start with a review of data capture methods, working, in turn, through a low cost system to research simple tapping, complex movements, use of video, inertial measurement units, and dedicated sensorimotor synchronisation software. This is followed by a section on music performance, which includes topics on the selection of music materials, sound recording, and system latency. The identification of events in the data stream can be challenging and this topic is treated in the next section, first for movement then for music. Finally, we cover methods of analysis, including alignment of the channels, computation of between channel asynchrony errors and modelling of the data set

Multi-agent Collision Avoidance Using Interval Analysis and Symbolic Modelling with its Application to the Novel Polycopter

Coordination is fundamental component of autonomy when a system is defined by multiple mobile agents. For unmanned aerial systems (UAS), challenges originate from their low-level systems, such as their flight dynamics, which are often complex. The thesis begins by examining these low-level dynamics in an analysis of several well known UAS using a novel symbolic component-based framework. It is shown how this approach is used effectively to define key model and performance properties necessary of UAS trajectory control. This is demonstrated initially under the context of linear quadratic regulation (LQR) and model predictive control (MPC) of a quadcopter. The symbolic framework is later extended in the proposal of a novel UAS platform, referred to as the ``Polycopter" for its morphing nature. This dual-tilt axis system has unique authority over is thrust vector, in addition to an ability to actively augment its stability and aerodynamic characteristics. This presents several opportunities in exploitative control design. With an approach to low-level UAS modelling and control proposed, the focus of the thesis shifts to investigate the challenges associated with local trajectory generation for the purpose of multi-agent collision avoidance. This begins with a novel survey of the state-of-the-art geometric approaches with respect to performance, scalability and tolerance to uncertainty. From this survey, the interval avoidance (IA) method is proposed, to incorporate trajectory uncertainty in the geometric derivation of escape trajectories. The method is shown to be more effective in ensuring safe separation in several of the presented conditions, however performance is shown to deteriorate in denser conflicts. Finally, it is shown how by re-framing the IA problem, three dimensional (3D) collision avoidance is achieved. The novel 3D IA method is shown to out perform the original method in three conflict cases by maintaining separation under the effects of uncertainty and in scenarios with multiple obstacles. The performance, scalability and uncertainty tolerance of each presented method is then examined in a set of scenarios resembling typical coordinated UAS operations in an exhaustive Monte-Carlo analysis

Textured insoles affect the plantar pressure distribution while elite rowers perform on an indoor rowing machine

Introduction: During rowing, foot positioning on the foot stretcher is critical to optimise muscle force transmission and boat propulsion. Following the beneficial effects of textured insoles on gait and balance, this study aims at investigating whether passive stimulation of foot mechanoreceptors induced by these insoles may contribute to improving foot loading pattern and symmetry during indoor rowing. Methods: Eleven elite rowers were assessed during controlled training on a standard rowing machine while wearing control, low-density or high-density textured insoles. Plantar pressure and knee and trunk kinematics were measured; performance data were recorded from the machine. Insole effect on kinematic parameters, peak and average values of foot force, contact area and position of centre of pressure was assessed with ANOVA and Bonferroni correction for pair-wise comparisons. Results: A main effect was observed for force and contact area, with the high-density insoles providing greatest values (P0.190), even though symmetry was higher with high-density insoles. Kinematics (P = 0.800) and rowing performance were not affected by insole type; a consistent though not statistically significant increase in mean travelled distance was observed for denser insoles (P>0.21). Conclusion: The high-density textured insoles affected foot loading distribution during indoor rowing. Rowers applied greater foot force and over a greater foot stretcher area with the high-density than the low-density and control insoles. These findings and the methodology applied may be relevant for the understanding and monitoring of rowing performance. © 2017 Vieira et al

ESTCube-1 asendi määramine

Väitekirja elektrooniline versioon ei sisalda publikatsioone.Uuring viidi läbi Tartu Ülikoolis, Tartu Observatooriumis, Soome Meteoroloogia instituudis ja Eesti tudengisatelliidi programmis. Doktoritöös tutvustatakse satelliidi ESTCube-1 asendi määramise süsteemi, mille otstarve on satelliidi orientatsiooni kindlakstegemine erinevate taustsüsteemide suhtes. ESTCube-1 on ehitatud vastavalt CubeSat standardi nõuetele (≈ 10 cm × 10 cm × 10 cm) ja saadeti orbiidile 2013. aasta mais, kus see tegutses kuni 2015. aasta maini. Selle põhimissiooniks oli katsetada Maa orbiidil elektrilise päikesepurje tehnoloogiaid. Elektriline päikesetuulepuri on uudne Päikesesüsteemis liikumise moodus, mis kasutab tõukejõu saamiseks Päikeselt väljapursatavate elektriliselt laetud osakeste voogu ehk päikesetuult. ESTCube-1 asendi määramise süsteemi põhieesmärgiks on leida satelliidi orientatsioon parema täpsusega kui 2° järgmiste tegevuste jaoks: satelliidi suure kiirusega pöörlema panemisel (sajad kraadid sekundis) tsentrifugaaljõu abil purje väljakerimiseks ja selle protsessi jälgimiseks, päikesepurje elektrilisel laadimisel sünkroonis satelliidi pöörlemisega ning mõõtmaks nurkkiiruse muutumist laetud päikesepurje ja ionosfääri plasma vahelise elektrostaatiline jõu tulemusel. Asendi määramise süsteem koosneb magnetomeetridest, nurkkiiruseanduritest ja Päikese suuna anduritest. Maa magnetvälja ja Päikese asukoha mudeleid kasutati vastavate andurite mõõtmistega võrdlemiseks. Asendi määramiseks kasutati Kalmani filtrit. Süsteem karakteriseeriti laboratooriumis ja simulatsioonidega enne starti. Orbiidil parendati süsteemi oluliselt tarkvara uuenduste ja uuesti karakteriseerimisega. Sõltumatuks valideerimiseks kasutati satellidi poolt tehtud fotodel põhinevat orientatsiooni leidmise meetodit. Süsteemi karakteriseerimise ja valideerimisega näidati, et asendi määramise täpsus on parem kui 1,75° mis täidab eksperimendi poolt seatud nõudeid.This research was carried out at the University of Tartu, Tartu Observatory, the Finnish Meteorological Institute and the Estonian Student Satellite Programme. This thesis presents the ESTCube-1 attitude determination system. The attitude is the satellite's orientation is space. ESTCube-1 is a satellite built according to the one-unit CubeSat standard (≈ 10 cm × 10 cm × 10 cm). The satellite was launched in May 2013 and operated until May 2015. The main scientific mission of ESTCube-1 was to perform the first in-orbit electric solar wind sail demonstration. The electric solar wind sail is a propellantless propulsion technology concept. The sail consists of long, thin, centrifugally stretched and positively charged tethers that deflect charged particles in the solar wind, hence generate spacecraft thrust. The main requirement of the ESTCube-1 attitude determination system is to determine the attitude with an accuracy better than 2° for the following purposes: high rate spin control (hundreds of degrees per second) for centrifugal tether deployment; monitoring of tether deployment; to trigger the charging of the tether in synchronisation with the satellite spin; to measure angular velocity changes caused by the Coulomb drag interaction between the charged tether and the surrounding ionospheric plasma. The attitude determination system has Sun sensors, magnetometers and gyroscopic sensors. A geomagnetic field model and a Sun position model were used to reference the respective sensor measurements. A Kalman filter was used to estimate the attitude. Before the launch, the system was characterised in the laboratory and by simulations. With in-orbit recalibration and validation, the system was significantly improved. For validation, an independent attitude determined from on-board images was used. By characterising and validating the system, it was shown that attitude determination accuracy is better than 1.75°, hence fulfils the requirement set by the electric solar wind sail experiment.

Body sensor networks: smart monitoring solutions after reconstructive surgery

Advances in reconstructive surgery are providing treatment options in the face of major trauma and cancer. Body Sensor Networks (BSN) have the potential to offer smart solutions to a range of clinical challenges. The aim of this thesis was to review the current state of the art devices, then develop and apply bespoke technologies developed by the Hamlyn Centre BSN engineering team supported by the EPSRC ESPRIT programme to deliver post-operative monitoring options for patients undergoing reconstructive surgery. A wireless optical sensor was developed to provide a continuous monitoring solution for free tissue transplants (free flaps). By recording backscattered light from 2 different source wavelengths, we were able to estimate the oxygenation of the superficial microvasculature. In a custom-made upper limb pressure cuff model, forearm deoxygenation measured by our sensor and gold standard equipment showed strong correlations, with incremental reductions in response to increased cuff inflation durations. Such a device might allow early detection of flap failure, optimising the likelihood of flap salvage. An ear-worn activity recognition sensor was utilised to provide a platform capable of facilitating objective assessment of functional mobility. This work evolved from an initial feasibility study in a knee replacement cohort, to a larger clinical trial designed to establish a novel mobility score in patients recovering from open tibial fractures (OTF). The Hamlyn Mobility Score (HMS) assesses mobility over 3 activities of daily living: walking, stair climbing, and standing from a chair. Sensor-derived parameters including variation in both temporal and force aspects of gait were validated to measure differences in performance in line with fracture severity, which also matched questionnaire-based assessments. Monitoring the OTF cohort over 12 months with the HMS allowed functional recovery to be profiled in great detail. Further, a novel finding of continued improvements in walking quality after a plateau in walking quantity was demonstrated objectively. The methods described in this thesis provide an opportunity to revamp the recovery paradigm through continuous, objective patient monitoring along with self-directed, personalised rehabilitation strategies, which has the potential to improve both the quality and cost-effectiveness of reconstructive surgery services.Open Acces