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In old houses, the pipes can often be in poor conditions and require cleaning to improve air quality. There are robotic solutions to this problem but often only for large industrial pipes and not for regular pipes that you would find in your home. Pipes can often be hard to access and even harder to determine the pipe’s condition. This thesis aims to research and build a small robot that can travel through pipes, gather footage and attempt to clean them. The goal is to create a robot that can climb vertically in pipes, record video inside of the pipes and detect obstacles. After research was done a prototype was built. The prototype uses spring loaded pistons that pushes wheels against the walls of the pipes to provide friction for vertical travel. To be able to perform all these tasks, the robot uses tools that can be exchanged depending on what needs to done. The ability to turn in pipes has been ignored in this thesis due to time restrictions but could be done as future work. The resulting prototype is a robot that can steadily travel vertically through pipes, carry its own weight of 750 grams and an additional load of up to 500 grams. The robot is able to stop at pre-determined locations by measuring the distance it has travelled by using a hall-effect sensor. / I gamla hus kan ventilationsrör ofta vara i dåligt skick och vara i behov av städning eller reparation för att öka luftkvalitén. Det finns robotar som loser detta problem men de är ofta skapade för stora industriella rör och inte för rör som man hittar hemma. Rör kan ofta vara svåra att komma åt och det kan vara ännu svårare att veta vilket skick rören är i. Det här projektet ska ta fram en liten robot som kan färdas genom rör och spela in video. Om tid finns, ska den också städa upp i rören. Målet med projektet är att skapa en robot som kan klättra vertikalt i rör, spela in video inuti rören och upptäcka hinder. Efter forskning så byggdes en prototyp. Prototypen använder fjädrade kolvar som trycker hjulen mot väggarna i röret och utvecklar därmed friktion för att kunna färdas vertikalt. För att kunna utföra uppgifterna så kommer roboten att kunna använda olika verktyg som byts ut beroende på vad som behöver utföras. Möjligheten att kunna svänga i rören har ignorerats i det här projektet på grund av tidsbegränsning men bör ses över vid framtida utveckling. Den slutgiltiga prototypen är en robot som kan färdas stabilit vertikalt genom rör, lyfta sin egna vikt på 750 gram och en extra vikt på upp till 500 gram. Roboten kan också stanna vid förbestämda platser då den kan mäta hur långt den färdats genom att använda en hall effekt sensor.

This thesis explores the topic of light and migration and what actions through light can be done to improve the life quality of the inhabitants of temporary shelters/refugee camps. In this ambiance where there is the feeling of pain, destruction, unsafety, uncertainty and limited access to basic needs, only relying on the support of institutions. A wide range of needs need to be covered, however this thesis proposes to aid the migrants’ when they reach a refugee camp by the creation of Winkilab, a light post that becomes a universal communication tool and function simultaneously as light therapy to have a positive impact on the migrant’s emotions.

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In order to predict hydraulic jump characteristics for channel design, the jump height may be determined by calculating the subcritical sequent depth from momentum theory. In closed conduits, however, outlet submergence may fill the conduit entirely before the expected sequent depth is reached. This is called an incomplete or pressure jump (as opposed to a complete or free-surface jump), because pressure flow conditions prevail downstream. Since the momentum equation involves terms for the top width, area, and centroid of flow, the subcritical sequent depth is a function of the conduit shape in addition to the upstream depth and Froude number. This paper reviews momentum theory as applicable to closed-conduit hydraulic jumps and presents general solutions to the sequent depth problem for four commonly-shaped conduits: rectangular, circular, elliptical, and pipe arch. It also provides a numerical solution for conduits of any shape, as defined by the user. The solutions conservatively assume that the conduits are prismatic, horizontal, and frictionless within the jump length; that the pressure is hydrostatic and the velocity is uniform at each end of the jump; and that the effects of air entrainment and viscosity are negligible. The implications of these assumptions are briefly discussed. It was found that these solutions may be applied successfully to determine the subcritical sequent depth for hydraulic jumps in closed conduits of any shape or size. In practice, this may be used to quantify jump size, location, and energy dissipation.

This thesis presents results of an experimental investigation that characterizes the wall vibration of a pipe with turbulent flow passing through it. Specifically, experiments were conducted using a water flow loop to address three general phenomena. The topics of investigation were: 1) How does the pipe wall vibration depend on the average flow speed, pipe diameter, and pipe thickness for an unsupported pipe? 2) How does the behavior change if the pipe is clamp supported at various clamping lengths? 3) What influence does turbulence generation caused by holed baffle plates exert on the pipe response? A single pipe material (PVC) was used with a range of internal diameters from 5.08 cm to 10.16 cm and diameter to thickness ratios ranging from 8.90 to 16.94. The average flow speed that the experiments were conducted at ranged from 0 to 11.5 m/s. Pipe vibrations were characterized by accelerometers mounted on the pipe wall at several locations along the pipe length. Rms values of the pipe wall acceleration and velocity time series were measured at various flow speeds. Power spectral densities of the accelerometer data were computed and analyzed. Concurrent wall pressure fluctuation measurements were also obtained. The results show that for a fully developed turbulent flow, the rms of the wall pressure fluctuations is proportional to the rms of the wall acceleration and each scale nominally as the square of the average fluid velocity. Also, the rms of the pipe wall acceleration increases with decreasing pipe wall thickness. When changes were made in the pipe support length, it was observed that, in general, pipe support length exercises little influence on the pipe wall acceleration. The influence of pipe support length on the pipe wall velocity is much more pronounced. A non-dimensional parameter describing the pipe wall acceleration is defined and its dependence on relevant independent non-dimensional parameters is presented. Turbulence was induced using baffle plates with various sizes (2.54 cm to 0.159 cm) and numbers of holes drilled through them to provide a constant through area of 35.48 cm2 for each plate. Cavitation exists at high speeds for the largest holed baffle plates and this significantly increases the rms of the pipe wall acceleration. As the baffle plate hole size decreases, vibration levels were observed to return to levels that were observed when no baffle plate was employed. Power spectral densities of the accelerometer data from each baffle plate scenario were also computed and analyzed.

In this paper our goal is to describe how to find the growth of Thompson's group F with generators a and b. Also, by studying elements through pipe systems, we describe how adding a third generator c affects geodesic length. We model the growth of Thompson's group F by producing a grammar for reduced pairs of trees based on Blake Fordham's tree structure. Then we change this grammar into a system of equations that describes the growth of Thompson's group F and simplify. To complete our second goal, we present and discuss a computer program that has led to some discoveries about how generators affect the pipe systems. We were able to find the growth function as a system of 11 equations for generators a and b.

The market for maintenance of dwellings in the construction industry is only getting more significant due to the time factor. Dwellings are only getting older, and demands for refurbishment are getting more obligatory for tenant-owned cooperatives.  This study examines the project manager’s approach when dealing with tenant-owned cooperatives and the management of pipe replacement. What risks and factors that are important to identify to achieve a possible decrease in disturbances in pipe replacement projects. To answer the purpose and the research questions asked, eight interviews were conducted.  The interviews were project managers with different experience level in the field of pipe replacement. The questions asked were based on the theoretical aspect of this study to examine further strategies that could help to achieve a successful project. The result from the interviewees was then analyzed and compressed to understand main factors and identify strategies to decrease disturbance during a pipe replacement project. The result from this master thesis indicates that a well-functioned communication prevents unpredictable risks together with a comprehensive pre-study. When dealing with a non-professional client, the right approach and educational level have to be established in the first interaction. When asked to rank the critical success factors, the most important ones were; Human-related factors, Project procedures, and Project-related factors. This consequently, implies which areas that are important for a project manager. As for the result of using risk management in pipe replacement projects, it could be regarded as either the most important or one very important tool to generate a successful project. / Marknaden för underhåll av bostadsrättföreningars bostäder i byggbranschen blir bara allt större på grund av tidsfaktorn. Bostäder blir bara äldre och krav på renovering blir mer obligatorisk för bostadsrättsföreningarna.   Denna studie undersöker projektledarens synsätt om hur man hanterar bostadsrättföreningar och projektledningen av stambyte. Vilka risker och faktorer som är viktiga att identifiera för att uppnå så nära som möjligt ett störningsfritt projekt. För att svara på syftet och frågeställningar har åtta intervjuer genomförts. Intervjuerna var med projektledare med olika erfarenhetsnivåer inom stambyte. Frågorna var baserad på den teoretiska aspekten av denna studie för att undersöka strategier som skulle kunna bidra till att uppnå ett framgångsrikt projekt. Resultatet från intervjuerna analyserades och undersöktes för att sedan förstå huvudfaktorerna och därmed identifieringsstrategier för att minska störningarna under ett stambytesprojekt. Resultatet av detta examensarbete visar att en väl fungerande kommunikation hindrar oförutsägbara risker med en djup förstudie. När projekt ledarna arbetar med en icke-professionell beställare måste man redan från början etablera rätt inställning. När de som intervjuades frågades om att rangordna vilka av de kritiska framgångsfaktorerna som var de viktigaste, var följande resultat; Mänskliga faktorer, upphandlingsprocesser och Projektrelaterade faktorer. Följaktligen, innebär vilket område som är viktigt för en projektledare. När det gäller resultatet av att använda riskhantering i rörbytesprojekt, kan det betraktas som antingen det viktigaste eller ett mycket viktigt verktyg för att skapa ett framgångsrikt projekt.

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