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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Individualized Motion Monitoring by Wearable Sensor : Pre-impact fall detection using SVM and sensor fusion / Individanpassad rörelsemonitorering med hjälp av bärbara sensorer

Carlsson, Tor January 2015 (has links)
Among the elderly, falling represents a major threat to the individual health, and is considered as a major source of morbidity and mortality. In Sweden alone, three elderly are lost each day in accidents related to falling. The elderly who survive the fall are likely to be suffering from decreased quality of life. As the percentage of elderly increase in the population worldwide, the need for preventive methods and tools will grow drastically in order to deal with the increasing health-care costs. This report is the result of a conceptual study where an algorithm for individualized motion monitoring and pre-impact fall detection is developed. The algorithm learns the normal state of the wearer in order to detect anomalous events such as a fall. Furthermore, this report presents the requirements and issues related to the implementation of such a system. The result of the study is presented as a comparison between the individualized system and a more generalized fall detection system. The conclusion is that the presented type of algorithm is capable of learning the user behaviour and is able to detect a fall before the user impacts the ground, with a mean lead time of 301ms. / Bland äldre är risken för att drabbas av fallrelaterade skador överhängande, ofta med svåra fysiska skador och psykiska effekter som följd. Med en ökande andel äldre i befolkningsmängden beräknas även samhällets kostnad för vård att stiga. Genom aktiva samt preventiva åtgärder kan graden av personligt lidande och fallre- laterade samhällskostnader reduceras. Denna rapport är resultatet av en konceptuell studie där en algoritm för aktiv, individanpassad falldetektion utvecklats. Algoritmen lär sig användarens normala rörelsemönster och skall därefter särskilja dessa från onormala rörelsemönster. Rapporten beskriver de krav och frågeställningar som är relevanta för utvecklingen av ett sådant system. Vidare presenteras resultatet av studien i form av en jämförelse mellan ett individanpassat och generellt system. Resultatet av studien visar att algoritmen kan lära sig användarens vanliga rörelsemönster och därefer särskilja dessa från ett fall, i medelvärde 301ms innan användaren träffar marken.
82

IoT smart athletics : Boxing glove sensors implementing machine learning for an integrated training solution

Sosopoulos, Konstantinos, Woldu, Michael Tareke January 2021 (has links)
It is very common in everyday life for people to use data generated by sensors like accelerometers and gyroscopes, whether they are on the mobile phone, smartwatch or other smart devices, for analysis of their movement or tracking their habits. This study is focused on boxing, and proposes a test where the generated data are put through machine learning algorithms in order to output information on the type of punch thrown by the user. Furthermore, the possibility of implementing ML on Android is examined. This thesis was performed by conducting a literature study, and an experimental study. For the literature study, researches similar to this were examined to gather information and insight on what the most common practices are, regarding the setup of the device used to collect the data, both in terms of sensor placement on the body and sensor setup like the optimal data output rates. The experimental part was conducted using custom hardware implementing an accelerometer and a gyroscope in which the wearer of this device would proceed to throw 6 types of punches (jab, cross, left & right uppercut, and left & right hook) to generate the data to be analyzed. It was technically possible to use Android for ML, but it was the least optimum way to execute the algorithms, so a PC was used instead. After putting the data through multiple ML algorithms, the results show that with our current hardware set up it was not possible for the ML algorithms to adequately classify the type of punches with mediocre accuracy scores ranging from 37.37% - 59.16% depending on the algorithm.
83

Acceleration sensitivity study on coupled resonators for designing anti-shock tuning fork gyroscopes / 耐衝撃性を有する音叉型ジャイロスコープ設計のための結合共振子の加速度感度に関する研究

Praveen Singh Thakur 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18588号 / 工博第3949号 / 新制||工||1607(附属図書館) / 31488 / 京都大学大学院工学研究科マイクロエンジニアリング専攻 / (主査)教授 田畑 修, 教授 西脇 眞二, 准教授 土屋 智由, 教授 引原 隆士 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
84

Gyrolösning för samtliga maskiner / Gyrosolution for all machines

Ali, Heja, Sivarajah, Jayaravi Jedusan January 2020 (has links)
Detta examensarbete syftar till att hitta ett MEMS-gyroskop till W2000, en rengöringsrobot som finns hos Weda AB. Gyroskopet ska användas för att korrigera rengöringsrobotens kurs när den avviker från sin bestämda rutt. I dagsläget har inte W2000 någon sensor för att kunna rätta till sig. För att hitta det lämpligaste för rengöringsroboten så undersöktes ett antal MEMS-gyroskop genom att samla information och fakta samt kontakta olika företag för vägledning med vårt problem. Det MEMS-gyroskop som hittades och implementerades i W2000 var OMNI LPMS-CU2. Gyroskopet valdes på grund av att den hade samma utgångstyp och kommunikationsspråk som PLC:n som var inbyggd i W2000. Ett test utfördes för att se om det implementerade gyroskopet kunde kurskorrigera när den vreds från programmerade väg. Det blev ett lyckat resultat av testandet, W2000 kunde justera sig när den avvek. Examensarbetet föreslår rekommendationer och förbättringar för vidare arbete med det här projektet. Anledningen är att trots att det var ett tillfredställande resultat så var det bara det första steget för att göra W2000 optimal för att kunna använda gyroskopet och dess funktioner till fullo. Det måste göras ett antal mer tester och undersökningar på W2000 för att kunna implementera MEMS-gyroskopet i helhet. / The thesis work aims to find a MEMS gyroscope for the W2000, a cleaning robot available at Weda AB. The gyroscope will be used to correct the course of the cleaning robot when it deviates from its specified route. Currently the W2000 does not have a sensor to adjust. To find the most suitable gyroscope for the cleaning robot, several MEMS gyroscopes were examined by gathering information and contacting various companies for guidance with our situation. The MEMS gyroscope which was found and implemented in W2000 was OMNI LPMS-CU2. The gyroscope was chosen because it had the same output type and communication protocol as the PLC built into the W2000. A test was performed to see if the implemented gyroscope could correct the course as it was turned from programmed path. The result of testing was successful which shows that the W2000 was able to adjust when it deviated. The degree project proposes recommendations and improvements for further work on this project. Although it was a satisfying result, it was only the first step in making it functional. Several tests and investigations must be done on the W2000 in order to implement the MEMS gyroscope as a whole.to insert text
85

ADAPTIVE SLIDING MODE CONTROL WITH APPLICATION TO A MEMS VIBRATORY GYROSCOPE

Fei, Juntao January 2007 (has links)
No description available.
86

Techniques to Characterize Vapor Cell Performance for a Nuclear-Magnetic-Resonance Gyroscope

Mirijanian, James Julian 01 May 2012 (has links) (PDF)
Research was performed to improve the procedures for testing performance parameters of vapor cells for a nuclear-magnetic-resonance gyroscope. In addition to summarizing the theoretical infrastructure of the technology, this research resulted in the development and successful implementation of new techniques to characterize gyro cell performance. One of the most important parameters to measure for gyro performance is the longitudinal spin lifetime of polarized xenon atoms in the vapor cell. The newly implemented technique for measuring these lifetimes matches results from the industry standard method to within 3.5% error while reducing the average testing time by 76% and increasing data resolution by 54%. The vapor cell test methods were appended with new software to expedite the analysis of test data and to investigate more subtle details of the results; one of the two isotopes of xenon in the cells tends to exhibit troublesome second-order effects during these tests due to electric-quadrupole coupling, but now the added analysis capabilities can accurately extract relevant results from such data with no extra effort. Some extraneous lifetime measurement techniques were explored with less substantial results, but they provided useful insight into the complex workings of the gyro cell test system. New criteria were established to define the signal to noise ratio on a consistent basis from cell to cell across various parameters such as cell volume, temperature, and vapor pressure. A technique for measuring gas pressures inside the sealed cells helped link cell performance to cell development processes. This led to informed decisions on filling and sealing methods that consistently yielded cells with better performance in the last few months of this work. When this research began, cells with xenon lifetimes over ten seconds were rare in our lab; by the end, anything under 30 seconds was a disappointment. Not only did the test procedures improve, but so did the parameters being tested, and quite significantly at that. At the same time, many new avenues for continued progress have been opened; the work presented here, while instrumental, is only the beginning.
87

The Water Entry of Slender Axisymmetric Bodies: Forces, Trajectories and Acoustics

Bodily, Kyle Gordon 08 July 2013 (has links) (PDF)
Free surface water entry of various objects has been studied using high-speed images and image processing techniques for decades. This thesis studies the forces, velocities, and trajectories of slender axisymmetric projectiles using an embedded inertial measurement unit (IMU). Three nose shapes (cone, ogive, and flat) were used in the study. Additionally, the projectiles were tested at vertical and oblique impact angles with different surface conditions. One-half of each projectile was coated down the centerline with a hydrophobic spray, creating a half hydrophobic, half hydrophilic case. The trajectory of this half-and-half case impacting vertically was compared to the trajectory of symmetrically coated projectiles impacting the free surface at oblique angles. The oblique impact cases showed significantly more final lateral displacement than the half-and-half case over the same depth. The amount of lateral displacement was also affected by the nose shape, with the cone nose shape achieving the largest lateral displacement for the oblique entry case. Instantaneous lift and drag coefficients were calculated using data from the IMU for the vertical, half-and-half, and oblique entry cases. Impact forces were calculated for each nose shape and the flat nose shape experienced impulsive forces between 25 N and 37 N when impacting vertically. The impact force for the flat nose decreased for the oblique entry case. Acoustic spectrograms showed that the sound produced during the water entry event predominately arises from the pinch-off for the cone and ogive nose shapes, with additional sound production from impact for the flat nose shape.
88

Attitude Reference Devices for Gun-Launched Rocket Vehicles

Hill, William Barry 10 1900 (has links)
<p> A proposal is made to extend the present capabilities of gun-launched rocket vehicles to include attitude control during flight. The problems involved are stated and design criteria for possible sensors are listed. A review of presently available sensing devices is made and rejection of unsuitable instruments is based on fundamentals of their design and operation. </p> <p> A report is made upon the sensors which most adequately fulfil the harsh environmental requirements of gun-launch. These sensors are infrared-horizon sensors and a tuning fork vibratory gyroscope. A preliminary design is given for the tuning fork gyroscope a well as a summary of fundamental design considerations. </p> / Thesis / Master of Engineering (ME)
89

Design and Analysis of Wafer-Level Vacuum-Encapsulated Disk Resonator Gyroscope Using a Commercial MEMS Process

Uppalapati, Balaadithya 20 December 2017 (has links)
No description available.
90

A System for Collecting Data to Characterize a Pre-Fall Change in Sway: Development and Proof-of-Concept Analyses

Sipp, Amy Renae 12 May 2008 (has links)
No description available.

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