Diploma work describes in its theoretical part particular types of pairs of wheels used on railway vehicles in Czech Republic as well as their components and assembly instructions. Practical part describes workplace for wheels in reparation DPOV, a.s. at repairing centre Nymburk, its facilities and repairing possibilities by total repair of pairs of wheels. Practical part brings at the end particular report with results of pairs of wheels measuring.

This thesis is oriented to technological and design direction. It is focused on the upgrading of existing machinery from a structural perspective. There is studied the impact of design modifications to the existing production process from a technological point of view. This thesis is specifically concentrated on the technology division of the material, especially on the technology cutting-off in dry condition. There is examined the ability of self-sharpening cutting tools and the quality of the final product under varying input conditions. The job is finished by the carried out techno-economic evaluation, where are compared the costs of the structural adjustments in comparison with mechanical equipment, that could be purchased on the market. The thesis is finished with overall analysis of the optimal efficiency of the production process.

Older adults are living longer than ever before. By 2060, the U.S. population aged 65 or older is projected to reach 98 million. As adults age, the prevalence of chronic diseases and disabilities increases. The need for Meals on Wheels (MOW) services is growing alongside the aging population. Yet, little is known about the geographic variation of services. Little is documented about the organizational capacity of MOW organizations in terms of geography. The current policies supporting home-and community-based services, including MOW, may be insufficient to support all older adults in all types of communities. An analysis of the More Than a Meal® Comprehensive Network Study was conducted to determine geographic variation in services delivered through MOW programs and to document organizational capacity by geography. Chi-squared analyses were performed to identify relationships between twenty services offered through MOW organizations and categorial offerings within nutrition, in-home safety, socialization, and community connections categories. Spidergrams were created to document organizational capacity holistically and for three individual organizations for each of the geographic areas: Rural Only, Partial Rural, and Non-rural Service Areas. Using these findings, a policy analysis was conducted to determine policy recommendations to inclusively support rural older adults. Older adults living in rural areas access the full complement of services provided by MOW programs differently than do their non-rural counterparts. Specifically, a statistically significant relationship was found between the stratified component of in-home safety for rural, partial rural and non-rural service areas. When evaluated on the individual service offering level, statistically significant relationships between rurality and congregate meals, nutrition education, nutrition assessment, coordination of USDA food assistance programs, and telephone reassurance were seen. Spidergram documentation of capacity created visual representations of geographic similarities and differences. The policy analysis produced three potentially viable policy additions for the Older Americans Act around a provision for innovation programs, a report on in-home safety, and business acumen provisions. This work lays the foundation for further analysis of existing data with a lens of geographic specificity, as well as articulates the importance of looking at organizational capacity as a part of policy recommendations for understanding rural community-based organizations.

With growing space market and entry of more private companies into the industry, there arecompanies and stakeholders who would like to have a high order of accuracy mission outputrequirements. These requirements vary from mission to mission. This simply means that if acompany wants an Earth observation mission, the main requirement to be fulfilled would be tohave the highest resolution of image possible. In order to achieve this, the satellite carrying the camera payload would be required to bepointed in the right direction with utmost accuracy. For a satellite to be pointed in the rightdirection, the noise generated by the sensors and actuators on-board, which determines theattitude of the satellite and helps in changing it, should be minimized. The aim of this thesisis to design a method which could help in determining the right components to be procuredso that the pointing requirements of the satellite are fulfilled. This objective is achieved bydesigning algorithms in python and MATLAB. The values generated by these algorithms, ultimately describe the type of sensor or actuator to be procured. Finally, the noise generated bysuch individual components act as pointing error source and then PEET is used to translatethese error sources to platform error, to generate a pointing budget and ensure that all pointingrequirements are satisfied.

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The inherited rotation in a caster wheel allows movement in any direction, but pays at the expense of reaction torques. When implemented in a mobile robot, these forces have a negative impact in its performance. One approach is to restrict rotations on the spot by attaching a filter to the output of the motion planner. However, this formulation compromises the navigation’s completion in critical scenarios, such as parking, taking curves in narrow corridors or navigating at the presence of a high density of obstacles. Therefore, in this thesis we consider the influence of caster wheels in the motion planning stage, commonly presented as local planning. This work proposes a Model Predictive Control (MPC) based local planner that integrates the caster wheel physics into the motion planning stage. A caster wheel aware term is combined with a reference tracking based navigation, which leads to the formulation of the Caster Wheel Aware Local Planner (CWAWLP). Since this method requires knowing the caster wheel’s state and there is no sensor that provides this information, a caster wheel state observer is also formulated. In order to evaluate the impact of the caster wheel aware term, CWAWLP is compared to a Caster Wheel based Agnostic Local Planner (CWAGLP) and a Caster Wheel based Agnostic Planner Local Planner with Path Filter (CWPFLP). After running simulations for three case studies in a virtual framework, two experimental case studies are conducted in an intra-logistics robot. These are evaluated according to the navigation’s quality, motor torque usage and energy consumption. According to the patterns observed in the evaluation, CWAWLP covers a longer distance than CWAGLP wihout decreasing the navigation’s quality. At the same time, its motor torques are similar to the ones of CWPFLP. Therefore, CWAWLP is capable of considering caster wheel physics without sacrificing navigation capabilities. The formulated caster wheel aware term is compatible with any MPC based navigation algorithm and inherits the derivation of an observer capable of estimating caster wheel rotation angles and rolling speeds. Even if the caster wheel awareness has been implemented in a differential driven robot, this approach is also applicable to vehicles with an alternative drivetrain, such as car-like robots. / Den ärvda rotationen i ett hjul möjliggör rörelse i vilken riktning som helst, men fås på bekostnad av reaktionsmoment. När de implementeras i en mobil robot har dessa krafter en negativ inverkan på dess prestanda. Ett tillvägagångssätt är att begränsa rotationer på plats genom att applicera ett filter på rörelseplannerns utgång. Denna formulering komprometterar dock navigeringens slutförande i kritiska scenarier, såsom parkering, kurvor i smala korridorer eller navigering i närheten av höga hinder. Därför beaktar vi i denna avhandling påverkan av hjul på hjulplaneringen, som ofta presenteras som lokal planering. Detta arbete föreslår en Model Predictive Control (MPC) -baserad lokal planerare som integrerar svängbara länkhjuls fysik i rörelseplaneringsstadiet. En kugghjulmedveten term kombineras med en referensspårningsbaserad navigering, vilket leder till formuleringen av Caster Wheel Aware Local Planner (CWAWLP). Eftersom denna metod kräver kunskap om svängbara länkhjuls tillstånd och det inte finns någon sensor som ger denna information, formuleras också en hjulhjulstillståndsobservatör. För att utvärdera effekten av det medvetna begreppet svängbara änkhjul jämförs CWAWLP med en Caster Wheel-baserad Agnostic Local Planner (CWAGLP) och en Caster Wheel-baserad Agnostic Planner Local Planner with Path Filter (CWPFLP). Efter att ha kört simuleringar för tre fallstudier i ett virtuellt ramverk genomförs två experimentella fallstudier i en intra-logistikrobot. Dessa utvärderas enligt navigeringens kvalitet, vridmomentanvändning och energiförbrukning. Enligt de mönster som observerats i utvärderingen når CWAWLP ett längre avstånd än CWAGLP utan att sänka navigeringens kvalitet. Samtidigt liknar motorns vridmoment dem som CWPFLP. Därför kan CWAWLP ta hänsyn till svängbara länkhjuls fysik utan att offra navigationsfunktionerna. Den formulerade medhjulningsmedveten termen är kompatibel med vilken MPC-baserad navigationsalgoritm som helst och ärver härledningen av en observatör som kan uppskatta hjulets rotationsvinklar och rullningshastigheter. Även om hjulhjälpmedvetenheten har implementerats i en differentierad robot, är detta tillvägagångssätt också tillämpligt på fordon med ett alternativt drivsystem, såsom billiknande robotar.

The purpose of this project was to study how hand gesture control can be implemented on a vehicle that utilizes mecanum wheels in order to move in all directions. Furthermore, it was investigated how the steering of such a vehicle can be made wireless to increase mobility. A prototype vehicle consisting of four mecanum wheels was constructed. Mecanum wheels are such wheels that enable translation in all directions. By varying rotational direction of each wheel, the direction of the resulting force on the vehicle is altered, making it move in the desired direction. Hand gesture control was enabled by constructing another prototype, attached to the hand, consisting of an IMU (Inertial Measurement Unit) and a transceiver. With the IMU, the hand’s angle against the horizontal plane can be calculated and instructions can be sent over to the vehicle by making use of the transceiver. Those instructions contain a short message that specifies in what direction the vehicle should move. The vehicle rotates the wheels in the desired direction and move thereafter. The results show that wireless hand gesture based control of an omnidirectional vehicle works without any noticeable delay in the transmission and the signals that are sent contain the correct information about moving directions. / Syftet med detta projekt var att studera hur handstyrning kan implementeras på ett fordon som utnyttjar mecanumhjul för att röra sig i alla riktningar. Vidare undersöktes också hur styrningen av sådant fordon kan genomföras trädlöst för ökad mobilitet. En prototypfarkost bestående av fyra mecanumhjul konstruerades. Mecanumhjul är sådana hjul som möjliggör translation i alla riktningar. Genom att variera rotationsriktningen på vardera motor ändras riktningen av den resulterande kraften på farkosten, vilket gör att den kan förflytta sig i önskad riktning. Handstyrning möjliggjordes genom att konstruera en till prototyp, som fästs i anslutning till handen, bestående av en IMU och en transceiver. Med IMU:n kan handens vinkel gentemot horisontalplanet beräknas och instruktioner kan skickas över till farkosten med hjälp av transceivern. Dessa instruktioner innehåller ett kort meddelande som specificerar i vilken riktning farkosten ska röra sig i. Resultaten visar på att trädlös handstyrning av en farkost fungerar utan märkbar tidsfördröjning i signalöverföring och att signalerna som skickas till farkosten innehåller korrekta instruktioner gällande rörelseriktningar.

The city of Shanghai was transformed from a treaty port of around half a million people when the British first arrived after the end of the Opium War to become the most populous, prosperous, and cosmopolitan metropolis in China by the early 20th century. The development of public transportation systems contributed significantly to the urban expansion and growth of the city, as well as in reshaping the city's identity. This dissertation examined the impact of public transportation on the urban landscape of Shanghai by focusing on three major issues: "tradition versus modernity", state and society relations, and the relationship between technology and society. As a divided city governed by three separate political jurisdictions, Shanghai offered a unique perspective in understanding the roles public transportation and urban planning played in changing a city's layout. This dissertation addressed the specific differences in the development of urban infrastructure and its impact on population growth, mobility and accessibility, and economic prosperity of the British controlled International Settlement, the French Concession, and the Chinese city. The first half of the dissertation analyzed the roles in which "traditional" man-powered vehicles such as the wheelbarrow, sedan chair, horse-drawn carriage, and rickshaw played, before delving into the arrival of "modern" machine-powered vehicles such as automobiles, trams, trolleys, and buses in the early 20th century. Each form of transportation vehicle is discussed for its specific role, and the type of clientele it catered. This dissertation argued that man-powered vehicles and machine-powered vehicles did not necessarily compete with each other for passengers, as each type of vehicle served its specific purposes and clients. Public transportation; just like food, clothing, or housing is a form of material culture where one's socioeconomic or class status is revealed by the type of transport one chooses. Because the different types of vehicles did not directly compete with each other, they all saw significant increases in ridership. The 'tradition versus modernity" theme is aimed at addressing the bigger picture of "continuity and change", where Shanghai was transformed by foreign influences yet at the same time it still retained traditional Chinese characteristics to form a complex identity. The second half of the dissertation dealt with state and society relations, and the relationship of technology and society. The issue of public versus private responsibility is addressed with historical analysis of government orchestrated urban planning and the private sector providing the services to fulfill the people's needs and demands. In focusing on these two themes, this dissertation argued that technology has inherent political agenda attached to it, as government policies specifically created areas of the city which had better public transportation infrastructure, which led to these parts of the city being more commercially prosperous and vibrant than others. Routes, lines, and stops were designated with specific political purposes in mind, and public transportation accessibility contributed to the uneven economic developments across the city. The Greater Shanghai Project of 1927-1937 was a specific attempt by the Chinese government to create a new city center that could shift the population away from the foreign concessions into the Chinese territories. This dissertation argued that this campaign would not have been feasible even without the Japanese attack due to insufficient public funds. The findings in this dissertation will hopefully add to the scholarship on the history of Shanghai and the history of technology in China.

This study evaluated the impact of receiving a home-delivered meal on the quality of life and nutritional risk of elders who were unable to attend congregate meal sites and who were unable to safely prepare a hot meal. Forty-three subjects on a waiting list were matched with a group currently receiving home-delivered meals. Matching criteria were functional needs measure, age, gender, and living arrangement.Home visits were conducted to collect the data and verify demographic information. Nutritional risk was assessed by the Nutrition Screening Initiative's Determine Checklist. Quality of life was measured across various domains including a global quality of life self-rating, mental health appraisal, functional ability, and food enjoyment. Two tailed t-tests failed to show differences in quality of life and nutritional risk between the groups at the 0.05 level of significance.In addition, the study reviewed the resources for meal preparation and grocery shopping possessed by the meal non-recipients that allowed them to remain at home without a meal provided. A significant difference was seen in the number of resources reported for meal preparation assistance with the meal non-recipient group reporting more informal resources. / Department of Family and Consumer Sciences