Este trabalho apresenta um sistema de rastreamento de obstáculos, utilizando sensor laser 2D e filtro de Kalman. Este filtro não é muito eficiente em situações em que ocorrem severas perturbações na posição medida do obstáculo, como, por exemplo, um objeto rastreado passando por trás de uma barreira, interrompendo o feixe de laser por alguns instantes, tornando impossível receber do sensor as informações sobre sua posição. Este trabalho sugere um método de minimizar esse problema com o uso de um algoritmo denominado Corretor de Discrepâncias. / An obstacle detection and tracking system using a 2D laser sensor and the Kalman filter is presented. This filter is not very efficient in case of severe disturbances in the measured position of the obstacle, as for instance, when an object being tracked is behind a barrier, thus interrupting the laser beam, making it impossible to receive the sensor information about its position. This work suggests a method to minimize this problem by using an algorithm called Corrector of Discrepancies.

Este trabalho apresenta um sistema de rastreamento de obstáculos, utilizando sensor laser 2D e filtro de Kalman. Este filtro não é muito eficiente em situações em que ocorrem severas perturbações na posição medida do obstáculo, como, por exemplo, um objeto rastreado passando por trás de uma barreira, interrompendo o feixe de laser por alguns instantes, tornando impossível receber do sensor as informações sobre sua posição. Este trabalho sugere um método de minimizar esse problema com o uso de um algoritmo denominado Corretor de Discrepâncias. / An obstacle detection and tracking system using a 2D laser sensor and the Kalman filter is presented. This filter is not very efficient in case of severe disturbances in the measured position of the obstacle, as for instance, when an object being tracked is behind a barrier, thus interrupting the laser beam, making it impossible to receive the sensor information about its position. This work suggests a method to minimize this problem by using an algorithm called Corrector of Discrepancies.

A participação econômica da cana-de-açúcar (Saccharum spp.) é expressiva no agronegócio brasileiro, especialmente no estado de São Paulo. O monitoramento de produtividade para essa cultura é escasso de soluções consolidadas no nível de pesquisa e comercialmente. Tal monitoramento auxilia na identificação das variabilidades espacial e temporal, além de fornecer subsídio ao gerenciamento agrícola. Como uma alternativa os sensores a laser, abrangidos pela tecnologia LiDAR (Light Detection and Ranging), têm sido utilizados por meio de plataformas aéreas ou terrestes para a estimativa de produtividade de culturas de grãos como milho e trigo, e para o monitoramento de florestas de modo não invasivo. O objetivo deste estudo é a investigação de aplicação do sensor a laser para a cana-de-açúcar em período pré-colheita a partir do desenvolvimento de um sistema de mensuração. O sistema é composto por um sensor a laser, receptor GNSS (Global Navigation Satellite System), uma unidade inercial e um computador portátil. O sensor a laser emite feixes de luz (905 nm) na forma de um único pulso em um plano 2D, a partir desses feixes os valores de distância entre o sensor e o dossel de plantas são calculados durante a trajetória do veículo agrícola. O receptor GNSS com sinal RTK (Real Time Kinematic) foi sincronizado ao sensor a laser para a obtenção da nuvem de pontos, a qual é caracterizada pela alocação de cada ponto impactado pelo feixe de luz nas respectivas coordenadas geográficas. A unidade inercial fornece informações relacionadas à influência da vibração a partir dos dados de oscilação na transversal (roll), lateral (pitch) e longitudinal (yaw). Os equipamentos foram instalados em um suporte de estrutura metálica no trator agrícola e conectados ao computador por meio de protocolos de comunicação. O desenvolvimento do sistema de mensuração envolve a avaliação de sua acurácia utilizando objetos de dimensões pré-estabelecidas e a sua aplicação em áreas experimentais de cana-de-açúcar. São abrangidos dois períodos de estudo, sendo um em 2015 para a área I (0,77 ha) e o segundo em 2016 utilizando as áreas I e II (0,56 ha). A aquisição de dados ocorreu cerca de 10 dias antes da colheita e, em paralelo, foram realizadas as medidas de biometria das plantas. Em 2015 a produtividade foi estimada pela biometria e em 2016 ocorreu a pesagem do material para cada parcela das áreas I e II. Os resultados referentes à avaliação da acurácia do sistema de mensuração demonstraram erros de até 13,0%, o qual não compromete o seu desempenho. A partir dos procedimentos de aquisição e processamento de dados foi possível gerar a nuvem de pontos, realizar a filtragem de dados e extrair as medidas de alturas máxima, média e mediana da vegetação. A influência da vibração no conjunto de dados foi considerada mais expressiva para as condições da área I. A correlação entre o diâmetro de colmos e a produtividade estimada pela biometria na área I em 2015 foi de 0,80. Enquanto que, a correlação entre o diâmetro de colmos e a altura de vegetação indicada pelo sistema de mensuração foi moderada (r=-0,53). Em 2016, para a mesma área, a correlação entre as medidas de altura média e mediana de vegetação obtidas pelo sistema e a produtividade foi de 0,64. Para as condições da área II não foram verificadas correlações entre as medidas de biometria e as alturas de vegetação. O sistema de mensuração utilizando uma plataforma terrestre apresentou desempenho satisfatório em relação à capacidade de detecção da distribuição de plantas de cana-de-açúcar e condizente com as condições das áreas em ambos os períodos de estudo, porém a sua aplicação em áreas com pouca variabilidade espacial apresentou baixa capacidade preditiva de produção de biomassa de cana-de-açúcar. / The economic participation of sugarcane (Saccharum spp.) is significant in Brazilian agribusiness, especially in the state of São Paulo. The yield monitoring for this crop is scarce of solutions consolidated at the research and commercial levels. Such monitoring assists for identification of spatial and temporal variability, as well as providing support to the agricultural management. As an alternative laser sensors, covered by LiDAR (Light Detection and Ranging) technology, have been used by aerial or terrestrial platforms for estimating grain crops yield such as corn and wheat, and for noninvasive forest monitoring. The objective of this study is to investigate the laser sensor applications for sugarcane in the pre-harvest period from development of a measurement system. The measurement system consists of a laser sensor, a Global Navigation Satellite System (GNSS) receiver, an inertial unit and a computer. The laser sensor emits light beams (905 nm) in the form of a single pulse in a 2D plane, from these beams the distance values between sensor and canopy were calculated during the trajectory of the agricultural vehicle. The GNSS receiver with RTK (Real Time Kinematic) signal was synchronized to the laser sensor to obtain the point cloud, which is characterized by the allocation of each point impacted by the light beam in the respective geographical coordinates. The inertial unit provides information related to the data influence of the vibration from oscillation in the transversal (roll), lateral (pitch) and longitudinal (yaw). The equipment were installed in a support of metallic structure in the agricultural tractor and connected to the computer through communication protocols. The development of the measurement system involves evaluation of its accuracy using objects of pre-established dimensions and its application in experimental areas of sugarcane. Two periods are covered by this study, one in 2015 for area I (0.77 ha) and the second in 2016 using areas I and II (0.56 ha). The data acquisition occurred about 10 days before sugarcane harvest and, in parallel, the biometrics measurements were carried out. In 2015 sugarcane yield was estimated by biometry and in 2016 material was weighed for each plot of areas I and II. The results regarding evaluation of the measurement system accuracy showed errors up to 13.0%, which does not compromise its performance. From the data acquisition and processing procedures, it was possible the point cloud generation, data filtering performing and extraction of some measurements as maximum, average and median heights of vegetation. The influence of the vibration on data set was considered more expressive for area I conditions. The correlation between stem diameter and yield estimated by biometry in area I in 2015 was 0.80. Meanwhile, the correlation between stem diameter and vegetation height indicated by the measurement system was moderate (r=-0.53). In 2016, for the same area, the correlation between measurements of average and median heights of vegetation obtained by the system and sugarcane yield was 0.64. For area II conditions no correlations were verified between biometrics measurements and vegetation height. The measurement system using a terrestrial platform presented a satisfactory performance in relation to the capacity of detection of sugarcane plants distribution and consistent with areas conditions for both periods of study, however its application in areas with low spatial variability presented reduced predictive capacity of biomass production of sugarcane.

A participação econômica da cana-de-açúcar (Saccharum spp.) é expressiva no agronegócio brasileiro, especialmente no estado de São Paulo. O monitoramento de produtividade para essa cultura é escasso de soluções consolidadas no nível de pesquisa e comercialmente. Tal monitoramento auxilia na identificação das variabilidades espacial e temporal, além de fornecer subsídio ao gerenciamento agrícola. Como uma alternativa os sensores a laser, abrangidos pela tecnologia LiDAR (Light Detection and Ranging), têm sido utilizados por meio de plataformas aéreas ou terrestes para a estimativa de produtividade de culturas de grãos como milho e trigo, e para o monitoramento de florestas de modo não invasivo. O objetivo deste estudo é a investigação de aplicação do sensor a laser para a cana-de-açúcar em período pré-colheita a partir do desenvolvimento de um sistema de mensuração. O sistema é composto por um sensor a laser, receptor GNSS (Global Navigation Satellite System), uma unidade inercial e um computador portátil. O sensor a laser emite feixes de luz (905 nm) na forma de um único pulso em um plano 2D, a partir desses feixes os valores de distância entre o sensor e o dossel de plantas são calculados durante a trajetória do veículo agrícola. O receptor GNSS com sinal RTK (Real Time Kinematic) foi sincronizado ao sensor a laser para a obtenção da nuvem de pontos, a qual é caracterizada pela alocação de cada ponto impactado pelo feixe de luz nas respectivas coordenadas geográficas. A unidade inercial fornece informações relacionadas à influência da vibração a partir dos dados de oscilação na transversal (roll), lateral (pitch) e longitudinal (yaw). Os equipamentos foram instalados em um suporte de estrutura metálica no trator agrícola e conectados ao computador por meio de protocolos de comunicação. O desenvolvimento do sistema de mensuração envolve a avaliação de sua acurácia utilizando objetos de dimensões pré-estabelecidas e a sua aplicação em áreas experimentais de cana-de-açúcar. São abrangidos dois períodos de estudo, sendo um em 2015 para a área I (0,77 ha) e o segundo em 2016 utilizando as áreas I e II (0,56 ha). A aquisição de dados ocorreu cerca de 10 dias antes da colheita e, em paralelo, foram realizadas as medidas de biometria das plantas. Em 2015 a produtividade foi estimada pela biometria e em 2016 ocorreu a pesagem do material para cada parcela das áreas I e II. Os resultados referentes à avaliação da acurácia do sistema de mensuração demonstraram erros de até 13,0%, o qual não compromete o seu desempenho. A partir dos procedimentos de aquisição e processamento de dados foi possível gerar a nuvem de pontos, realizar a filtragem de dados e extrair as medidas de alturas máxima, média e mediana da vegetação. A influência da vibração no conjunto de dados foi considerada mais expressiva para as condições da área I. A correlação entre o diâmetro de colmos e a produtividade estimada pela biometria na área I em 2015 foi de 0,80. Enquanto que, a correlação entre o diâmetro de colmos e a altura de vegetação indicada pelo sistema de mensuração foi moderada (r=-0,53). Em 2016, para a mesma área, a correlação entre as medidas de altura média e mediana de vegetação obtidas pelo sistema e a produtividade foi de 0,64. Para as condições da área II não foram verificadas correlações entre as medidas de biometria e as alturas de vegetação. O sistema de mensuração utilizando uma plataforma terrestre apresentou desempenho satisfatório em relação à capacidade de detecção da distribuição de plantas de cana-de-açúcar e condizente com as condições das áreas em ambos os períodos de estudo, porém a sua aplicação em áreas com pouca variabilidade espacial apresentou baixa capacidade preditiva de produção de biomassa de cana-de-açúcar. / The economic participation of sugarcane (Saccharum spp.) is significant in Brazilian agribusiness, especially in the state of São Paulo. The yield monitoring for this crop is scarce of solutions consolidated at the research and commercial levels. Such monitoring assists for identification of spatial and temporal variability, as well as providing support to the agricultural management. As an alternative laser sensors, covered by LiDAR (Light Detection and Ranging) technology, have been used by aerial or terrestrial platforms for estimating grain crops yield such as corn and wheat, and for noninvasive forest monitoring. The objective of this study is to investigate the laser sensor applications for sugarcane in the pre-harvest period from development of a measurement system. The measurement system consists of a laser sensor, a Global Navigation Satellite System (GNSS) receiver, an inertial unit and a computer. The laser sensor emits light beams (905 nm) in the form of a single pulse in a 2D plane, from these beams the distance values between sensor and canopy were calculated during the trajectory of the agricultural vehicle. The GNSS receiver with RTK (Real Time Kinematic) signal was synchronized to the laser sensor to obtain the point cloud, which is characterized by the allocation of each point impacted by the light beam in the respective geographical coordinates. The inertial unit provides information related to the data influence of the vibration from oscillation in the transversal (roll), lateral (pitch) and longitudinal (yaw). The equipment were installed in a support of metallic structure in the agricultural tractor and connected to the computer through communication protocols. The development of the measurement system involves evaluation of its accuracy using objects of pre-established dimensions and its application in experimental areas of sugarcane. Two periods are covered by this study, one in 2015 for area I (0.77 ha) and the second in 2016 using areas I and II (0.56 ha). The data acquisition occurred about 10 days before sugarcane harvest and, in parallel, the biometrics measurements were carried out. In 2015 sugarcane yield was estimated by biometry and in 2016 material was weighed for each plot of areas I and II. The results regarding evaluation of the measurement system accuracy showed errors up to 13.0%, which does not compromise its performance. From the data acquisition and processing procedures, it was possible the point cloud generation, data filtering performing and extraction of some measurements as maximum, average and median heights of vegetation. The influence of the vibration on data set was considered more expressive for area I conditions. The correlation between stem diameter and yield estimated by biometry in area I in 2015 was 0.80. Meanwhile, the correlation between stem diameter and vegetation height indicated by the measurement system was moderate (r=-0.53). In 2016, for the same area, the correlation between measurements of average and median heights of vegetation obtained by the system and sugarcane yield was 0.64. For area II conditions no correlations were verified between biometrics measurements and vegetation height. The measurement system using a terrestrial platform presented a satisfactory performance in relation to the capacity of detection of sugarcane plants distribution and consistent with areas conditions for both periods of study, however its application in areas with low spatial variability presented reduced predictive capacity of biomass production of sugarcane.

Hypersonic vehicles, based on scramjet engines, have the potential to deliver inexpensive access to space when compared with rocket propulsion. The technology, however, is in its infancy and there is still much to be learned from fundamental studies.¶ Flows that represent the conditions inside a scramjet engine can be generated in ground tests using a free-piston shock tunnel and a combustor model. These facilities provide a convenient location for fundamental studies and principles learned during ground tests can be applied to the design of a full-scale vehicle.¶ A wide range of diagnostics have been used for studying scramjet flows, including surface measurements and optical visualisation techniques.¶ The aim of this work is to test the effectiveness of tunable diode laser absorption spectroscopy (TDLAS) as a scramjet diagnostic.¶ TDLAS utilises the spectrally narrow emission from a diode laser to probe individual absorption lines of a target species. By varying the diode laser injection current, the laser emission wavelength can be scanned to rapidly obtain a profile of the spectral line. TDLAS has been used previously for gas-dynamic sensing applications and, in the configuration used in this work, is sensitive to temperature and water vapour concentration.¶ The design of the sensor was guided by previous work. It incorporated aspects of designs that were considered to be well suited to the present application. Aspects of the design which were guided by the literature included the laser emission wavelength, the use of fibre optics and the detector used. The laser emission wavelength was near 1390 nm to coincide with relatively strong water vapour transitions. This wavelength allowed the use of telecommunications optical fibre and components for light delivery. Detection used a dual-beam, noise cancelling detector.¶ The sensor was validated before deployment in a low-pressure test cell and a hydrogen–air flame. Temperature and water concentration measurements were verified to within 5% up to 1550 K. Verification accuracy was limited by non-uniformity along the beam path during flame measurements.¶ Measurements were made in a scramjet combustor operating in a flow generated by the T3 shock tunnel at the Australian National University. Within the scramjet combustor, hydrogen was injected into a flame-holding cavity and the sensor was operated downstream in the expanded, supersonic, post-combustion flow. The sensor was operated at a maximum repetition rate of 20 kHz and could resolve variation in temperature and water concentration over the 3ms running time of the facility.¶ Results were repeatable and the measurement uncertainty was smaller than the turbulent fluctuations in the flow. The scramjet was operated at two fuel-lean equivalence ratios and the sensor was able to show differences between the two operating conditions. In addition, vertical traversal of the sensor revealed variation in flow conditions across the scramjet duct.¶ The effectiveness of the diagnostic was tested by comparing results with those from other measurement techniques, in particular pressure and OH fluorescence measurements, as well as comparison with computational simulation.¶ Combustion was noted at both of the tested operating conditions in data from all three measurement techniques.¶ Computation simulation of the scramjet flow significantly under-predicted the water vapour concentration. The discrepancy between experiments and simulation was not apparent in either the pressure measurements or the OH fluorescence, but was clear in the diode laser results.¶ The diode laser sensor, therefore, was able to produce quantitative results which were useful for comparison with a CFD model of the scramjet and were complimentary to information provided by other diagnostics.

<p>The aim of the thesis has been to study methods to minimize the slosh when moving liquid-filled packages in packaging machines. An automatic method for generation of the movement of a package in a packaging machine is of growing importance. The main reason is that reduced slosh leads to increased production rate. Progress within measurement technology creates possibilities for new solutions. One purpose has been to find methods and equipment to detect the height of the wave, perhaps at several places or alternatively the entire liquid surface shape. When suitable equipment for detection of the wave movements was found, collected measurements were analyzed and criteria for describing improvements of the slosh properties have been formulated. </p><p>Initially a sensor specification was written in order to simplify the search for suitable equipment. Sources of information have mainly been catalogues and Internet. The search resulted in that a number of sensors were borrowed for tests. The results of the tests supported the choice of the most suitable sensor, in this case a laser sensor. The main reason is that the sensors detection ability is good compared to its price. An analysis of the sensors most important properties confirmed the choice of the laser sensor. To be able to compare waves, criteria for what is considered to be good wave properties have been formulated and evaluated. </p><p>The work has confirmed that it is difficult to find a simple and cheap solution for wave detection given that the solution should have good detection ability. It has also been difficult to formulate simple but working criteria for wave performance, and this has led to a compromise between the complexity of the criterion functions and the result of the wave score. Ideas about how an automatic method, based on the chosen sensor and the criterion functions, can be implemented, have been introduced. During the work, some interesting discoveries have been made. These have led to better understanding of how some parameters should be chosen, to better understanding of wave movements and to better choice of future work.</p>

The aim of the thesis has been to study methods to minimize the slosh when moving liquid-filled packages in packaging machines. An automatic method for generation of the movement of a package in a packaging machine is of growing importance. The main reason is that reduced slosh leads to increased production rate. Progress within measurement technology creates possibilities for new solutions. One purpose has been to find methods and equipment to detect the height of the wave, perhaps at several places or alternatively the entire liquid surface shape. When suitable equipment for detection of the wave movements was found, collected measurements were analyzed and criteria for describing improvements of the slosh properties have been formulated. Initially a sensor specification was written in order to simplify the search for suitable equipment. Sources of information have mainly been catalogues and Internet. The search resulted in that a number of sensors were borrowed for tests. The results of the tests supported the choice of the most suitable sensor, in this case a laser sensor. The main reason is that the sensors detection ability is good compared to its price. An analysis of the sensors most important properties confirmed the choice of the laser sensor. To be able to compare waves, criteria for what is considered to be good wave properties have been formulated and evaluated. The work has confirmed that it is difficult to find a simple and cheap solution for wave detection given that the solution should have good detection ability. It has also been difficult to formulate simple but working criteria for wave performance, and this has led to a compromise between the complexity of the criterion functions and the result of the wave score. Ideas about how an automatic method, based on the chosen sensor and the criterion functions, can be implemented, have been introduced. During the work, some interesting discoveries have been made. These have led to better understanding of how some parameters should be chosen, to better understanding of wave movements and to better choice of future work.

With global emission regulations becoming stringent, development of new combustion technologies that meet future emission regulations is essential. In this vein, this dissertation presents the application of sensitive diagnostic tools to validate and improve chemical kinetic mechanisms that play a fundamental role in the design of new combustion technologies. First, a novel high sensitivity laser-based sensor with a wide frequency tuning range (900 – 1000 cm-1) was developed utilizing pulsed cavity ringdown spectroscopy (CRDS) technique. The novel laser-based sensor was illustrated by measuring trace amounts of multiple combustion intermediates, namely ethylene, propene, allene, and 1-butene in a static cell at ambient conditions. Subsequently, pulsed CRDS technique was utilized to develop an ultra-fast, high sensitivity diagnostic to monitor trace concentrations of ethylene in shock tube pyrolysis experiments. This diagnostic represented the first ever successful application of CRDS technique to transient species measurements in a shock tube. The high sensitivity and fast time response (10μs) diagnostic may be utilized for measuring other key neutrals and radicals which are crucial in the oxidation chemistry of practical fuels. Secondly, a quadrupole mass spectrometer (QMS) was employed to measure relative cation mole fractions in atmospheric and low-pressure (30 Torr) flames of methane/oxygen diluted in argon. Lean, stoichiometric and rich flames were 4 examined to evaluate the dependence of ion chemistry on flame stoichiometry. Spatial distribution of cations was compared with predictions of an existing ion chemistry model. Based on the extensive measurements carried out in this work, modifications were suggested to improve the ion chemistry model to enhance the fidelity of such mechanisms. In-depth understanding of flame ion chemistry is vital to model the interaction of flames with electric fields and thereby pave the way to enable active combustion control for increased efficiency and reduced emissions. Finally, a compact fast time-response time-of-flight mass spectrometer (TOFMS) was coupled to the shock tube through a pin-hole end-wall to enable timeresolved species concentration measurements. This diagnostic tool was demonstrated by investigating the decomposition of 1,3,5-trioxane over a wide range of shock conditions. Reaction rate coefficients were extracted by the best fit to the experimentally measured species time-histories. TOF-MS coupled to the shock tube is an ideal diagnostic tool for developing kinetic mechanisms for future fuels due to its ability to simultaneously measure several species during fuel pyrolysis/oxidation processes.

Robot manipulators are considered as the key element in flexible manufacturing systems. Nonetheless, for a successful accomplishment of robot integration, the robots need to be accurate. The leading source of inaccuracy is the mismatch between the prediction made by the robot controller and the actual system. This work presents techniques for identification of actual kinematic parameters and pose accuracy compensation using a laser-based 3-D measurement system. In identification stage, both direct search and gradient methods are utilized. A computer simulation of the identification is performed using virtual position measurements. Moreover, experimentation is performed on industrial robot FANUC Robot R-2000iB/210F to test full pose and relative position accuracy improvements. In addition, accuracy obtained by classical parametric methodology is improved by the implementation of artificial neural networks. Neuro-parametric method proves an enhanced improvement in simulation results. The whole proposed theory is reflected by developed simulation software throughout this work while achieving accuracy nine times better when comparing before and after implementation.

This thesis describes basic concepts, principles and properties of optical fibers. Considerable part is devoted to fiber gratings that are created by a change in the refractive index in the optical fiber core. In this work is described description, principle, method od production and distribution of gratings on Bragg gratings, gratings with long period and chirped gratings. In this thesis are also presented different types of lasers and their advantages over other lasers. A large part deals with the description of the femtosecond laser, with which the structures will be later made into the material. In addition, the laser modes are differentiated, this is a mode of micro-machining and modification or a change in refractive index of the material. The last part deals with change the refractive index in planar technology, the creation of a groove for fastening the fiber and attempts to write the gratings into the optical fiber. Created fiber sensor are tested for temperature and tensile changes. Finally, the practical use of sensors made by femtosecond laser and the advantages over UV laser and phase mask techniques are presented.