Engineering Commons^™

Mems Capacitive Strain Sensing Elements For Integrated Total Knee Arthroplasty Prosthesis Monitoring, Boyd Mccutchen Evans Iii

Doctoral Dissertations

Measuring the in vivo load state of Total Knee Arthroplasty (TKA) components is required to understand the structural environment and wear characteristics of the devices. The ability to acquire this information gives tremendous insight into the mechanics of the joint replacement prosthesis. Data corresponding to normal loads, in-plane loads, shear loads, load center, contact area, and the rate of loading is needed to fully understand the kinematics and kinetics of the orthopedic implant. In this research, a novel sensing system has been developed which is capable of fully characterizing three-dimensional strain and stress at a single location.

Capacitance-based sensors were …

Theoretical Modeling And Experimental Validation Of In Vivo Mechanics For Subjects Having Variable Cervical Spine Conditions, Fei Liu

Doctoral Dissertations

The objective of this study was to use the state-of-art 3D-to-2D registration technologies including fluoroscopic, CT and MRI methods to analyze 2D and 3D in vivo kinematics of the whole cervical spine under variable conditions; and use inverse dynamic model based on Kane’s dynamics to predict their 2D and 3D in vivo interactive contact and muscular forces. Totally, forty patients (ten having normal cervical spines, ten having degenerative cervical spines, ten having anterior cervical decompression and fusion (ACDF), and ten having cervical artificial disc replacement (CADR)) were enrolled into 2D study and three patients (one having normal cervical spines, one …

Characterization Of A Biomimetic Calcium-Deficient Hydroxyapatite-Bacterial Cellulose Composite, Stacy Hutchens

Doctoral Dissertations

Bone is the second most implanted tissue next to blood causing approximately 2.2 million people to receive bone grafts each year. Developing safe synthetic bone grafts allows quick and safe restoration of bone function while avoiding the surgical risks associated with bone autografting (self donation), and risks of disease transmission and immunogenic response associated with allografts (bone donated from other humans) and xenografts (grafts derived from animal tissue). This dissertation entails the study and development of a novel potential synthetic bone graft consisting of a composite of calcium-deficient hydroxyapatite (CdHAP) biomimetically deposited in a bacterial cellulose (BC) hydrogel.

To determine …

Design And Evaluation Of A Non-Intrusive Corn Population Sensor, Haizhou Li

Doctoral Dissertations

Specific objectives of this study were to develop, prototype, and test a corn population sensor. Both intrusive mechanical and non-intrusive capacitive techniques have been used to develop the stalk population sensors in previous research. However, neither could generate consistent performance. The mechanical method required high maintenance and resulted in significant underestimations of stalk counts. The performance of capacitive systems was limited by inadequate sensing distance, especially at low stalk moisture levels.

In this research, the sensitivity of the capacitive sensor was optimized for corn stalks. This system utilized a single-sided capacitive sensor, Wien bridge oscillator, phase-locked loop, and an operational …