Labor shortage has prompted researchers to develop robot platforms for agriculture field scouting tasks. Sensor-based automatic topographic mapping and scouting algorithms for rough and large unstructured environments were presented. It involves moving an image sensor to collect terrain and other information and concomitantly construct a terrain map in the working field. In this work, a triangular mesh map was first used to represent the rough field surface and plan exploring strategies. A 3D image sensor model was used to simulate collection of field elevation information.<p>A two-stage exploring policy was used to plan the next best viewpoint by considering both the distance and elevation change in the cost function. A greedy exploration algorithm based on the energy cost function was developed; the energy cost function not only considers the traveling distance, but also includes energy required to change elevation and the rolling resistance of the terrain. An information-based exploration policy was developed to choose the next best viewpoint to maximise the information gain and minimize the energy consumption. In a partially known environment, the information gain was estimated by applying the ray tracing algorithm. The two-part scouting algorithm was developed to address the field sampling problem; the coverage algorithm identifies a reasonable coverage path to traverse sampling points, while the dynamic path planning algorithm determines an optimal path between two adjacent sampling points.<p>The developed algorithms were validated in two agricultural fields and three virtual fields by simulation. Greedy exploration policy, based on energy consumption outperformed other pattern methods in energy, time, and travel distance in the first 80% of the exploration task. The exploration strategy, which incorporated the energy consumption and the information gain with a ray tracing algorithm using a coarse map, showed an advantage over other policies in terms of the total energy consumption and the path length by at least 6%. For scouting algorithms, line sweeping methods require less energy and a shorter distance than the potential function method.

Labor shortage has prompted researchers to develop robot platforms for agriculture field scouting tasks. Sensor-based automatic topographic mapping and scouting algorithms for rough and large unstructured environments were presented. It involves moving an image sensor to collect terrain and other information and concomitantly construct a terrain map in the working field. In this work, a triangular mesh map was first used to represent the rough field surface and plan exploring strategies. A 3D image sensor model was used to simulate collection of field elevation information.<p>A two-stage exploring policy was used to plan the next best viewpoint by considering both the distance and elevation change in the cost function. A greedy exploration algorithm based on the energy cost function was developed; the energy cost function not only considers the traveling distance, but also includes energy required to change elevation and the rolling resistance of the terrain. An information-based exploration policy was developed to choose the next best viewpoint to maximise the information gain and minimize the energy consumption. In a partially known environment, the information gain was estimated by applying the ray tracing algorithm. The two-part scouting algorithm was developed to address the field sampling problem; the coverage algorithm identifies a reasonable coverage path to traverse sampling points, while the dynamic path planning algorithm determines an optimal path between two adjacent sampling points.<p>The developed algorithms were validated in two agricultural fields and three virtual fields by simulation. Greedy exploration policy, based on energy consumption outperformed other pattern methods in energy, time, and travel distance in the first 80% of the exploration task. The exploration strategy, which incorporated the energy consumption and the information gain with a ray tracing algorithm using a coarse map, showed an advantage over other policies in terms of the total energy consumption and the path length by at least 6%. For scouting algorithms, line sweeping methods require less energy and a shorter distance than the potential function method.

[pt] Há uma crescente demanda pela criação de modelos computacionais representativos de objetos reais para projetos de engenharia. Uma alternativa barata e eficaz consiste na utilização de técnicas de Visão Computacional baseada em câmeras e projetores disponíveis no mercado de computadores pessoais. Este trabalho avalia um sistema óptico estéreo ativo para capturar formas geométricas de objetos utilizando um par de câmeras e um projetor digital. O sistema se baseia em idéias de trabalhos anteriores, com duas contribuições nesta dissertação. A primeira é uma técnica mais robusta de detecção de pontos notáveis em padrões de calibração das câmeras. A segunda contribuição consiste num novo método de ajuste de cilindros que visa aplicar o sistema estudado na inspeção de instalações de dutos industriais. As conclusões apresentadas procuram avaliar a robustez e precisão do sistema proposto como um instrumento de medidas em Engenharia. / [en] There has been a growing demand for creation of computer models based on real models for engineering projects. A cheap and effective alternative consists in using Computer Vision techniques based on cameras and projectors available at the personal computer market. This work evaluates a stereo optic system for capturing geometric shapes from objects using a pair of cameras and a single digital projector. The system is based on former works and a pair of contributions is obtained at this dissertation. The first contribution is a more robust technique for finding corners and points at cameras calibration patterns. And the second one consists on a new method for cylinder fit for inspecting industrial piping facilities with the studied system. The final conclusions evaluate the robustness and precision from the proposed system as a measurement tool for Engineering.

Det finns begränsad tillgång till pussel för personer med synfel (inklusive blinda personer). För att undersöka behovet av potentiella användare i 3D kartpussel och identifiera deras preferenser, behov och krav, användes en kvalitativ metod som på engelska kallas ”participatory design”. Projektet utfördes i Kreta och alla deltagare kom från ön. Då Icke-standardiserade subjekt användes i forskningsprojektet användes lämpliga tillgängliga metoder och kommunikationsvägar för att anpassa studien för denna grupp. Stor vikt lades ner på bakgrundsstudier, inklusive intervjuer med experter och undersökning av befintligt material inom detta ämne.  För att underlätta förståelsen av konceptet och skapa en gemensam referensram för alla deltagare gjordes funktionella 3D prototyper av  kartpussel föreställande Kreta. Prototyperna gjordes i trä, antingen tall eller MDF. Därefter organiserades fokusgrupper och intervjuer. I fokusgrupperna deltog vuxna och barn med synnedsättning. Aktiviteterna var scenariokreation, utvärdering av användarvänlighet och en enkätundersökning som fylldes in av de som kunde (personer med tillräckligt god syn).  Data som samlades analyserades med hjälp av kvalitativa och kvantitativa metoder. Resultatet av testerna visade potentiella användarvänlighetsproblem för prototyperna, de flesta relaterade till synskadade individers erfarenheter av linkande produkter. Dessutom identifierades deltagarnas preferenser och behov angående temat, storlek, material, typ av samband och andra faktorer av pusslet.  Resultaten visar att osäkerhet eller brist på bekräftelse huruvida pusselbitarna var lagda rätt eller fel var den största svårigheten bland deltagare med synnedsättning. Den mest populära metoden för låsning av pusselbitarna bland de med synnedsättning var ”fit in a frame” och ”magnets”. Majoriteten av deltagarna uppmuntrade att lägga till färger på pusslet och markera olika städer. Sex av åtta deltagare var intresserade av att köpa pussel liknande det som de testat. Av 22 icke synskadade personer svarade nio av dem att det är möjligt att de skulle köpa pusslet och elva svarade att det är väldigt möjligt att de skulle köpa tredimensionella pussel. Mer än hälften såg färger som ett tilläggselement på pusslet. De två mest populära låsningsmetoderna var ”loose contact” och ”fit in a frame”. Angående materialvalet, togs trä emot väl av både synskadade och icke-synskadade testpersoner. Träprototyper  var dock det enda tillgängliga under testet. Deltagare gav flera förslag angående temat, storlek och extra egenskaper för produkten. Det resulterade i att många idéer genererades under ”workshopen”. Utfall, problem och begränsningar relaterade till de använda metoderna diskuterades och rekommendationer för framtida studier gjordes. / There are a limited number of puzzles accessible to visually impaired people (including the blind population) and also limited 3D map-puzzles available in the market. In order to explore the interest of potential users in 3D map-puzzles and identify their preferences, needs and demands, a participatory design approach was adopted. The project took place in Crete and all participants came from the local population. Because of the non-standard population included in this research project (visually impaired people) accessible methods and means of communication had to be selected. Therefore an extensive background research was performed, including interviews with experts and a thorough study of existing knowledge and previous research in related fields.  Aiming to facilitate understanding of the concept and to provide a common point of reference for all participants, functional prototypes of a 3D map-puzzle of the island of Crete were developed and manufactured. Prototypes were made of wood, either Pine or MDF. Subsequently, focus group and interview sessions were organized. Visually impaired and sighted, adults and children, participated in these sessions which included usability testing of the prototypes, scenario creation and a questionnaire (for the sighted participants). Data collected in the conducted sessions were analyzed using qualitative and quantitative methods. The results revealed usability problems of the prototypes and provided signs of potential problems, most of them related to the use of similar products by visually impaired individuals. Additionally, preferences and needs of the participants about the theme, the size, the material, the type of connection and other elements of the puzzle, were identified. According to the findings, the most severe problem, occurring when visually impaired participants tried to assemble the puzzle, was the uncertainty or “lack of confirmation” whether pieces were assembled in the right way or not. The most popular connection types among visually impaired participants were “fit in a frame” and “magnet”. Additionally, the majority of visually impaired participants were in favor of adding colors on the puzzle and marks for the different cities. Regarding buying interest, six out of eight visually impaired participants stated that they would buy a puzzle like the one they tested. Out of the twenty-two sighted participants, nine answered that it is “possible” and eleven answered that it is “highly possible” to buy a 3D map-puzzle. More than half of the sighted participants selected colors as an additional element on the puzzle while the two most popular connection types were “loose contact” and “fit in a frame”. Regarding the material of the puzzle, wood was well accepted by both sighted and visually impaired participants. However, only prototypes made from wood were available to the participants.  Additionally, participants made various suggestions regarding the theme, the size and additional elements of a 3D puzzle. As a result, many ideas were produced during the sessions. Eventually, outcomes, problems and limitations related to the methods used during the study were discussed and recommendations for future work were made.

Det finns begränsad tillgång till pussel för personer med synfel (inklusive blinda personer). För att undersöka behovet av potentiella användare i 3D kartpussel och identifiera deras preferenser, behov och krav, användes en kvalitativ metod som på engelska kallas ”participatory design”. Projektet utfördes i Kreta och alla deltagare kom från ön. Då Icke-standardiserade subjekt användes i forskningsprojektet användes lämpliga tillgängliga metoder och kommunikationsvägar för att anpassa studien för denna grupp. Stor vikt lades ner på bakgrundsstudier, inklusive intervjuer med experter och undersökning av befintligt material inom detta ämne.  För att underlätta förståelsen av konceptet och skapa en gemensam referensram för alla deltagare gjordes funktionella 3D prototyper av  kartpussel föreställande Kreta. Prototyperna gjordes i trä, antingen tall eller MDF. Därefter organiserades fokusgrupper och intervjuer. I fokusgrupperna deltog vuxna och barn med synnedsättning. Aktiviteterna var scenariokreation, utvärdering av användarvänlighet och en enkätundersökning som fylldes in av de som kunde (personer med tillräckligt god syn).  Data som samlades analyserades med hjälp av kvalitativa och kvantitativa metoder. Resultatet av testerna visade potentiella användarvänlighetsproblem för prototyperna, de flesta relaterade till synskadade individers erfarenheter av linkande produkter. Dessutom identifierades deltagarnas preferenser och behov angående temat, storlek, material, typ av samband och andra faktorer av pusslet.  Resultaten visar att osäkerhet eller brist på bekräftelse huruvida pusselbitarna var lagda rätt eller fel var den största svårigheten bland deltagare med synnedsättning. Den mest populära metoden för låsning av pusselbitarna bland de med synnedsättning var ”fit in a frame” och ”magnets”. Majoriteten av deltagarna uppmuntrade att lägga till färger på pusslet och markera olika städer. Sex av åtta deltagare var intresserade av att köpa pussel liknande det som de testat. Av 22 icke synskadade personer svarade nio av dem att det är möjligt att de skulle köpa pusslet och elva svarade att det är väldigt möjligt att de skulle köpa tredimensionella pussel. Mer än hälften såg färger som ett tilläggselement på pusslet. De två mest populära låsningsmetoderna var ”loose contact” och ”fit in a frame”. Angående materialvalet, togs trä emot väl av både synskadade och icke-synskadade testpersoner. Träprototyper  var dock det enda tillgängliga under testet. Deltagare gav flera förslag angående temat, storlek och extra egenskaper för produkten. Det resulterade i att många idéer genererades under ”workshopen”. Utfall, problem och begränsningar relaterade till de använda metoderna diskuterades och rekommendationer för framtida studier gjordes. / There are a limited number of puzzles accessible to visually impaired people (including the blind population) and also limited 3D map-puzzles available in the market. In order to explore the interest of potential users in 3D map-puzzles and identify their preferences, needs and demands, a participatory design approach was adopted. The project took place in Crete and all participants came from the local population. Because of the non-standard population included in this research project (visually impaired people) accessible methods and means of communication had to be selected. Therefore an extensive background research was performed, including interviews with experts and a thorough study of existing knowledge and previous research in related fields.  Aiming to facilitate understanding of the concept and to provide a common point of reference for all participants, functional prototypes of a 3D map-puzzle of the island of Crete were developed and manufactured. Prototypes were made of wood, either Pine or MDF. Subsequently, focus group and interview sessions were organized. Visually impaired and sighted, adults and children, participated in these sessions which included usability testing of the prototypes, scenario creation and a questionnaire (for the sighted participants). Data collected in the conducted sessions were analyzed using qualitative and quantitative methods. The results revealed usability problems of the prototypes and provided signs of potential problems, most of them related to the use of similar products by visually impaired individuals. Additionally, preferences and needs of the participants about the theme, the size, the material, the type of connection and other elements of the puzzle, were identified. According to the findings, the most severe problem, occurring when visually impaired participants tried to assemble the puzzle, was the uncertainty or “lack of confirmation” whether pieces were assembled in the right way or not. The most popular connection types among visually impaired participants were “fit in a frame” and “magnet”. Additionally, the majority of visually impaired participants were in favor of adding colors on the puzzle and marks for the different cities. Regarding buying interest, six out of eight visually impaired participants stated that they would buy a puzzle like the one they tested. Out of the twenty-two sighted participants, nine answered that it is “possible” and eleven answered that it is “highly possible” to buy a 3D map-puzzle. More than half of the sighted participants selected colors as an additional element on the puzzle while the two most popular connection types were “loose contact” and “fit in a frame”. Regarding the material of the puzzle, wood was well accepted by both sighted and visually impaired participants. However, only prototypes made from wood were available to the participants.  Additionally, participants made various suggestions regarding the theme, the size and additional elements of a 3D puzzle. As a result, many ideas were produced during the sessions. Eventually, outcomes, problems and limitations related to the methods used during the study were discussed and recommendations for future work were made.

A highly accurate sensor for measuring distances, used for creating high-resolution 3D maps of the environment, utilize “Light Detection And Ranging” (LiDAR) technology. This degree project aims to investigate the implementation of 3D LiDAR sensors into off-highway vehicle display computers, called CCpilots. This involves a study of available low-cost 3D LiDAR sensors on the market and development of an application for visualizing real time data graphically, with room for optimization algorithms. The selected LiDAR sensor is “Livox Mid-360”, a hybrid-solid technology and a field of view of 360° horizontally and 59° vertically. The LiDAR application was developed using Livox SDK2 combined with a C++ back-end, in order to visualize data using Qt QML as the Graphical User Interface design tool. A filter was utilized from the Point Cloud Library (PCL), called a voxel grid filter, for optimization purpose. Real time 3D LiDAR sensor data was graphically visualized on the display computer CCpilot X900. The voxel grid filter had a few visual advantages, although it consumed more processor power compared to when no filter was used. Whether a filter was used or not, all points generated by the LiDAR sensor could be processed and visualized by the developed application without any latency.