The purpose of this paper is to design a laser scanning system for a high temperature and acidic environment to measure small-scale surface roughness of seabed and to collect information related to calcium carbonate debris. The study comprises two parts. One is to construct the hardware and software of the laser scanning system. Two is to test the system at sea. The system were tested at Kuishantao sea area, an area with many submarine springs. The temperature of the hot water from the submarine springs can be as high as 126¢XC. Key substances from this type of hot springs are surfur and air bubbles composed of CO2, N2, O2, SO2, and H2S. These chemicals make the sea water in this area acidic, and the pH value can be less than 2. In other words, this sea area is a high temperature and very acidic environment According the acidic resistant test result, the researchers decided to use Polypropylene (PP) as the material. The laser scanning system captures information automatically, and it uses industrial single board computer (PC104) as the control platform. The researchers selected red laser, which is monotonous, directional, and coherent Lithium batteries, can be recharged repetitively, were used to supply the power. High-precision positioning, high resolution, and with easy speed and angle control stepping motors were chosen for the system. For the software, the researchers chose the Window operating system. The hardware and software of this system are highly compatible. Operating the system is very intuitive because windows are used as the interface, and the hardware has high supporting capacity. This arrangement makes data analysis later on very convenient. Images acquired from conducting the actual experiment at sea that need to be processed. A CCD camcorder with fixed location and angle was used to capture images. With the high brightness characteristic of laser and simple threshold values for screening, the researchers got the pixel position of laser beans. Then a calibrated the camcorder was used to switch the pixel coordinates to obtain the actual size of the object.

To make a camera more user friendly or let it operate without an user the camera objective needs to be able to put thecamera lens in focus. This functionality requires a motor of some sort, due to its many benefits the ultrasonic motor is apreferred choice. The motor requires a driving circuit to produce the appropriate signals and this is what this thesis is about.Themain difficulty that needs to be considered is the fact that the ultrasonic motor is highly non-linear.This paper will give a brief walk through of how the ultrasonic motor works,its pros and cons and how to control it. How thedriving circuit is designed and what role the various components fills. The regulator is implemented in C-code and runs on amicro processor while the actual signal generation is done on a CPLD. The report ends with a few suggestions of how toimprove the system should the presented solution not perform at a satisfactory level.

[pt] Neste trabalho descreve-se as partes de potência e de controle de um inversor trifásico existente na PUC / RJ e o estudo, em pormenor, do sistema de controle com microcomputador. A seguir, são descritas as interfaces entre o micro e o inversor e faz-se a modelação do sistema para o controle. Baseado nesta modelagem é feito o programa de um controlador proporcional-integral (PI) e o estudo de estabilidade do sistema. Os testes das interfaces projetadas e do controle PI acionando o inversor são apresentados e discutidos. Finalmente, são apresentadas as conclusões do trabalho desenvolvido. / [en] This work begins with a description of the power and the control section of a three-phase inverter, and a discussion of the control system with microcomputer. The microcomputer-inverter interfaces are described and a model for the system is developed. Based on this model, a proportional-integral (PI) controller algorithm is presented and the system stability is studied. The results of testes on the interfaces and the complete system are discussed, and the conclusions of this work are presented.

Hip-knee-ankle-foot (HKAF) prostheses are full lower limb devices for people with hip amputations. They are designed to enable individuals to regain their mobility and move freely with little restriction. HKAFs typically have high rejection rates among users, as well as gait asymmetry and increased trunk anterior-posterior lean and pelvic tilt. In this thesis, a novel integrated hip-knee (IHK) unit was designed and evaluated to address the limitations of existing solutions. This IHK combines powered hip and microprocessor controlled knee joints into one structure, with shared electronics, sensors, and batteries. The unit is also adjustable to the user leg length by a prosthetist. ISO-10328 standard mechanical testing demonstrated acceptable structural safety and rigidity. Successful functional testing involved three able-bodied participants walking with the IHK in a hip prosthesis simulator. Hip and knee joint angles and pelvic tilt angles were recorded, gait characteristics were analyzed using video recordings. Testing showed that the participants were able to walk using the IHK, and data showed that participants used different walking strategies. Points of improvement were identified for future development of the thigh unit, including completion of a synergistic gait control system, improved battery holding mechanism, and amputee user testing.

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