Embedded avionics with Kalman state estimation for a novel micro-scale unmanned aerial vehicle

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis. "June 2013."Includes bibliographical references (pages 107-109).An inertial navigation system leveraging Kalman estimation techniques and quaternion dynamics is developed for deployment to a micro-scale unmanned aerial vehicle (UAV). The capabilities, limitations, and requirements of existing navigation solutions motivate the need for an integrated solution that can be readily applied to small embedded systems and still provide reasonably accurate results. Methods to calibrate and compensate systemic inaccuracies in microelectromechanical systems (MEMS) sensors, commonly used in micro-scale UAV applications, are also developed. The problems associated with attitude determination and system localization are analyzed in isolation with incremental simulation and field testing. Performance is evaluated against commercially available inertial navigation system solutions. The result is a capable navigation system that, by its structure, trades a small measure of accuracy in order to be easily adapted to the embedded computing constraints of unmanned vehicles in the micro-scale.by Theodore Tzanetos.M. Eng

Factors associated with the subspecialty choices of internal medicine residents in Canada

<p>Abstract</p> <p>Background</p> <p>Currently, there are more residents enrolled in cardiology training programs in Canada than in immunology, pharmacology, rheumatology, infectious diseases, geriatrics and endocrinology combined. There is no published data regarding the proportion of Canadian internal medicine residents applying to the various subspecialties, or the factors that residents consider important when deciding which subspecialty to pursue. To address the concern about physician imbalances in internal medicine subspecialties, we need to examine the factors that motivate residents when making career decisions.</p> <p>Methods</p> <p>In this two-phase study, Canadian internal medicine residents participating in the post graduate year 4 (PGY4) subspecialty match were invited to participate in a web-based survey and focus group discussions. The focus group discussions were based on issues identified from the survey results. Analysis of focus group transcripts grew on grounded theory.</p> <p>Results</p> <p>110 PGY3 residents participating in the PGY4 subspecialty match from 10 participating Canadian universities participated in the web-based survey (54% response rate). 22 residents from 3 different training programs participated in 4 focus groups held across Canada. Our study found that residents are choosing careers that provide intellectual stimulation, are consistent with their personality, and that provide a challenge in diagnosis. From our focus group discussions it appears that lifestyle, role models, mentorship and the experience of the resident with the specialty appear to be equally important in career decisions. Males are more likely to choose procedure based specialties and are more concerned with the reputation of the specialty as well as the anticipated salary. In contrast, residents choosing non-procedure based specialties are more concerned with issues related to lifestyle, including work-related stress, work hours and time for leisure as well as the patient populations they are treating.</p> <p>Conclusion</p> <p>This study suggests that internal medicine trainees, and particularly males, are increasingly choosing procedure-based specialties while non-procedure based specialties, and in particular general internal medicine, are losing appeal. We need to implement strategies to ensure positive rotation experiences, exposure to role models, improved lifestyle and job satisfaction as well as payment schedules that are equitable between disciplines in order to attract residents to less popular career choices.</p

Investigation of the negative influence of cooling lubricants on the deformation of the machine tool structure

Cooling lubricants have a significant influence on the thermal state of a machine tool. The fluid absorbs the thermal energy of the cutting process and dissipates it to prevent wear of the tool and distortion of the work piece. However, the unpredictable flow of the cooling lubricant also transfers the energy to the machine tool structure and can thus have a negative impact on the produced work piece quality. While the thermal behaviour of machine tools under the influence of thermal environmental conditions is already the subject of ongoing research projects, the influence of cooling lubricants on the thermal state of the machine tool and thus the achievable manufacturing accuracy is still largely unexplored. This paper investigates the thermally induced deformations of the machine tool structure, as well as the impact on the Tool Centre Point (TCP)

Les patients comme enseignants : évaluer les expériences des patients hospitalisés bénévoles durant la formation sur les habiletés cliniques des étudiants en médecine

Purpose: Early patient exposure in medical education is an important element of clinical skill development. This study explores the experiences of volunteer inpatients (VIPs) participating in clinical skills training with junior medical students (JMS) solely for educational purposes. Methods: Following first-year medical students practicing history taking and clinical examinations on VIPs at Toronto General Hospital (TGH) and Toronto Western Hospital (TWH), patients completed a questionnaire and a short audio-recorded interview. This study used a mixed methodological approach. A 5-point Likert-scaled survey queried satisfaction regarding the recruitment process, student and faculty interactions and patient demographics (e.g. age and educational background). A 10-minute follow-up interview investigated patient perspectives. Survey responses were correlated to patient demographics and descriptive thematic analysis summarized trends in patient perspectives. Results: Of 93 consenting VIPs, 66% were male and 58% participated at TGH. The mean overall experience was positive (4.76 and 4.93 at TGH and TWH, respectively). Three themes emerging through thematic analysis were Not “Just” a Medical Student, Patient as Teacher, and Promoting Best Practices. VIPs had positive experiences when students communicated effectively through active listening and engaging patients, and when the VIP role was adequately explained during recruitment. Conclusion: Study results provide clarity about VIP experiences with JMS and lay a foundation for improved patient satisfaction and best practices within clinical skills curricula in the health professions.Objectif&nbsp;: L’exposition clinique précoce en éducation médicale est un élément important du développement des habiletés cliniques. Cette étude explore les expériences de patients hospitalisés bénévoles (PHB) qui participent à la formation sur les habiletés cliniques des étudiants de 1re année en médecine (ÉJM) à des fins purement éducatives. Méthodes&nbsp;: Après que les étudiants de première année aient effectué des anamnèses et des examens cliniques auprès de PHB à la Toronto General Hospital (TGH) et à la Toronto Western Hospital (TWH), les patients ont répondu à un questionnaire et ont fait une courte entrevue audio qui a été enregistrée. Cette étude a utilisé une approche méthodologique mixte. Un sondage basé sur l’échelle de Likert à 5 points a évalué le degré de satisfaction en ce qui a trait au processus de recrutement, aux interactions entre les étudiants et le corps professoral et aux caractéristiques démographiques des patients (p. ex. âge et niveau d’instruction). Une entrevue de suivi de dix minutes a permis d’examiner le point de vue des patients. Les réponses du sondage ont été mises en corrélation avec les caractéristiques démographiques des patients et une analyse thématique descriptive a résumé les tendances liées aux perspectives des patients. Résultats&nbsp;: Sur les 93 PHB consentants, 66 % étaient des hommes et 58 % d’entre eux ont participé à la TGH. En moyenne, l’expérience générale s’est avérée positive (4,76 et 4,93 à la TGH et à la TWH, respectivement). Les trois thèmes qui ont émergé de l’analyse thématique sont: pas « seulement » un étudiant en médecine; le patient comme enseignant et, la promotion des pratiques exemplaires. Les PHB ont rapporté avoir eu des expériences positives lorsqu’ils étaient bien informés de leur rôle durant le recrutement et lorsque les étudiants faisaient preuve de confiance, d’intérêt et de respect tout au long de la session. Conclusion : Les résultats de l’étude apportent des clarifications en ce qui a trait aux expériences des PHB avec les étudiants en première année de médecine, et ils jettent les bases qui permettront d’améliorer la satisfaction des patients et les meilleures pratiques du programme de formation en habiletés cliniques dans les professions de la santé

Mars Science Helicopter Conceptual Design

Robotic planetary aerial vehicles increase the range of terrain that can be examined, compared to traditional landers and rovers, and have more near-surface capability than orbiters. Aerial mobility is a promising possibility for planetary exploration as it reduces the challenges that difficult obstacles pose to ground vehicles. The first use of a rotorcraft for a planetary mission will be in 2021, when the Mars Helicopter technology demonstrator will be deployed from the Mars 2020 rover. The Jet Propulsion Laboratory and NASA Ames Research Center are exploring possibilities for a Mars Science Helicopter, a second-generation Mars rotorcraft with the capability of conducting science investigations independently of a lander or rover (although this type of vehicle could also be used assist rovers or landers in future missions). This report describes the conceptual design of Mars Science Helicopters. The design process began with coaxial-helicopter and hexacopter configurations, with a payload in the range of two to three kilograms and an overall vehicle mass of approximately twenty kilograms. Initial estimates of weight and performance were based on the capabilities of the Mars Helicopter. Rotorcraft designs for Mars are constrained by the dimensions of the aeroshell for the trip to the planet, requiring attention to the aircraft packaging in order to maximize the rotor dimensions and hence overall performance potential. Aerodynamic performance optimization was conducted, particularly through airfoils designed specifically for the low Reynolds number and high Mach number inherent in operation on Mars. The final designs show a substantial capability for science operations on Mars: a 31 kg hexacopter that fits within a 2.5 m diameter aeroshell could carry a 5 kg payload for 10 min of hover time or over a range of 5 km

Real operational data for the Concrete Delivery Problem

The dataset consists of 263 instances corresponding to daily orders of concrete from construction sites in Quebec, Canada. A concrete producer, i.e., a concrete-producing company that delivers concrete, provided the raw data. We cleaned the data by removing entries corresponding to non-complete orders. We processed these raw data to form instances useful for benchmarking optimization algorithms developed to solve the CDP. We also anonymized the published dataset by removing any client information and addresses corresponding to production or construction sites. The dataset is useful for researchers and practitioners studying the CDP. It can be processed to create artificial data for variations of the CDP. In its current form, the data contain information about intra-day orders. Thus, selected instances from the dataset are useful for CDP&apos;s dynamic aspect considering real-time orders