In the diagnosis and analysis of shoulder instability a precise determination of the location and orientation of the Glenohumeral joint is important. A better understanding of shoulder kinematics and kinetics will help clinicians and therapists in the diagnosis and treatment of shoulder pathologies. To-date, non-invasive skin-based methods are often either restricted to quasi-static measurements or are inaccurate during dynamic assessments at high humeral elevations as a result of soft skin artefact. Tracking the orientation of the scapula is difficult because it is surrounded by soft tissues, is held mainly by muscles and has only one direct point of attachment to the thorax. Instability of the glenohumeral joint generates poor functionality of the shoulder labrum and capsule as well as in the muscle and connective tissue structures that surround the shoulder. As the clinical phenomenon of shoulder instability is extremely complex, one of the priorities for the specialist in avoiding a faulty diagnosis is to recognise, identify and classify shoulder pathologies such as muscle patterning instability in the early stages of the investigation. A two stage methodology for non-invasive tracking of the scapula under dynamic conditions is presented in this work. The methodology provides scapula location by combining data from two surface mounted sensors using a regression-type equation formulated from quasi-static trials undertaken using a scapula locator and three IMUs (first stage). In the second stage, the least square fit is used to improve the scapular orientation by utilising data from only two IMUs (humerus and scapula) under dynamic conditions. Accuracy was assessed in an animal study by comparing results with those from a bone based method during quasi static and dynamic tests. Tests were also undertaken to investigate the errors induced by the soft tissue artefact in surface based scapula location measurement. In dynamic trials the methodology proved more accurate in determining scapula location than a standard skin-based approach, and showed that the greatest contribution to soft tissue artefact was from the epidermal, dermal and subcutaneous tissue layers as opposed to the muscle layer. We confirmed that, in cases where subjects have relatively small amounts of soft tissue surrounding the scapula, surface based methods could provide reasonable accuracy. Our methodology utilised subject-specific data to formulate a regression equation, and can be used to provide accurate, non-invasive tracking of the scapula under dynamic conditions in subjects regardless of individual body morphology. After the methodology validation, study tests were undertaken in a case study in order to estimate the scapula orientation under dynamic conditions in a human without symptoms of any shoulder pathologies and in one participant diagnosed with shoulder instability due to muscle patterning. The two stage methodology is proven to work in a healthy human participant in dynamic tests, in a person with no suspicion of shoulder instability. This methodology allows the error reduction generated by the soft tissues surrounded the scapula. The work presented here can be used as a framework for developing diagnosis protocols by using modern technology.

There exist numerous commercial six-degree-ofreedom inertial measurement units capable of measuring low-range accelerations and rotation rates. A commercially available multi-range IMU capable of measuring low and high-range motions does not exist. An IMU with this capability was developed for measuring trajectory data of projectiles such as high-powered rockets. This data can be used to provide performance feedback to projectile designers and users. A small footprint printed circuit board was designed to minimize the overall size of the unit, compared to “perf-board” prototypes. Several PCB design guidelines were closely followed to reduce electrical interference in digital/analog components and traces. Embedded C code was developed to control the IMU. The unit features a wireless user interface, providing several control options, including an option to download data sampled at 1KHz per sweep of all twelve sensor channels. Preliminary testing reveals good consistency among the high and low-range sensors and acceptably low noise levels.

No description available.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.115-120).

Thesis(M.S.)--Auburn University, 2006. / Abstract. Includes bibliographic references (p.105-107).

No description available.

Nonlinear Galerkin methods utilize approximate inertial manifolds to reduce the spatial error of the standard Galerkin method. For certain scenarios, where a rough forcing term is used, a simple postprocessing step yields the same improvements that can be observed with nonlinear Galerkin. We show that this improvement is mainly due to the information about the forcing term that is neglected by standard Galerkin. Moreover, we construct a simple postprocessing scheme that uses only this neglected information but gives the same increase in accuracy as nonlinear or postprocessed Galerkin methods. / Master of Science

MEMS gyroscopes are electromechanical devices that measure rate or angle of rotation. They are one of the fastest growing segments of the microsensor market. Advances in microfabrication technologies have enabled the implementation of chip scale monolithic gyroscopes (MEMS gyroscopes) with very small form factor that are lightweight and consume little power. Over the past decade, significant amount of research have been directed towards the development of high performance and very small size MEMS gyroscopes for applications in consumer electronics such as smart phones. In this dissertation, high aspect-ratio hemispherical shell structure with continuously curved surface is utilized as the high Q resonator. Being an axial symmetric structure, the 3D hemispherical shell is able to achieve low frequency (3 ~ 5 kHz) within 2 mm X 2mm die area. Detailed analysis on energy dissipation also shows its potential to achieve ultra-high quality factor with the selection of high Q material and proper design of support structure. This dissertation presents, for the first time, the analysis, design, fabrication and characterization of a micro-hemispherical resonating gyroscope (μHRG) that has the potential to be used as a whole angle micro-gyroscope. A three-dimensional high aspect-ratio poly- and single crystalline silicon (3D HARPSS) process is developed to fabricate free-standing, stem-supported hemispherical shell with self-aligned deep electrodes for driving, sensing and quadrature control of the gyroscope. This monolithic process consists of seven lithography steps and combines 3D micro-structure with curved surfaces with the HARPSS process to create capacitive electrodes with arbitrary gaps around the micro-hemispherical shell resonator (μHSR). Polysilicon is utilized as the structural material due to its isotropic mechanical properties and the potential of achieving high quality factor. The fabrication is demonstrated successfully by prototypes of polysilicon μHRG with diameter of 1.2 mm and thickness of 700 nm. Frequency response and gyro operation are electronically measured using the integrated electrodes. Quality factor of 8,500 is measured with frequency mismatch of 105 Hz. Electronic mode matching and alignment are successfully performed by applying tuning voltages and quadrature nulling voltages. An open loop rate sensitivity scale factor of 4.42 mV/°/s was measured. Design and process optimization of the support structure improved the quality factor to 40,000. Further improvement of quality factor will enable the demonstration of high performance RIG using polysilicon μHRG.

Thesis (M.S.)--University of Michigan, 1979.

Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.