Biomedical Devices and Instrumentation Commons^™

Integrated Compliant Structure For A Hand Exoskeleton, Tristan R. Koopman

Honors Undergraduate Theses

This thesis presents the design and prototyping of a wearable hand exoskeleton that integrates a flexible structural framework to assist with hand movement while maintaining comfort and anatomical conformity. The goal was to create a device that supports tendon-driven actuation through a compliant structure, combining elements of rigidity and flexibility to match the natural geometry and motion of the human hand. Traditional hand exoskeletons often trade off motion for structure or vice versa. This project aims to bridge that gap with a hybrid compliant design that balances flexibility and support. The design process followed an iterative approach involving rapid prototyping …

The Implementation And Miniaturization Of A New Current Source Into The Consolidated Layout Of An Electrical Impedance Tomography Probe With A Novel Approach To Electrode Layout, Katherine M. Bullion

Dartmouth College Master’s Theses

Prostate cancer is the most highly diagnosed form of cancer in male subjects in the United States. As a result, over 100,000 radical prostatectomies are performed annually in the US [1]. However, it is currently very difficult for surgeons to confirm that all impacted tissues have been effectively removed from the patient. Positive surgical margins are an independent risk factor for the recurrence of cancer, yet currently there is no method to efficiently, intraoperatively assess the status of surgical margins during a radical prostatectomy. There is a need for a new tool that is small enough to fit into a …

In Vitro Microfluidics System For Mechanobiologic Investigations, Michael A. Daanen

Honors Theses

Mechanobiology is an emerging field that aims to study the relationships between mechanical forces and cellular behavior. Such mechanobiological relationships are especially critical in the cardiovascular system, where endothelial cells lining the vasculature align in response to fluid shear stresses from blood flow (Sinha, 2016). Implanted flow devices, diabetes, chronic hypertension, and various other diseases and pathophysiologies alter vessel geometries and flow dynamics. Such alterations impact fluid shear stress and endothelial cell behavior, leading to microcirculatory dysfunction, vessel leakage, and organ failure (Poredos, 2021; Papadaki, 1999; Leitschuh, 1987). To simulate dysfunctional endothelial cell behavior in vitro and evaluate novel therapeutic …

Non-Invasive Glucose Monitoring Using Ppg, Ai, And Iot-Driven Mobile Integration For Real-Time Diabetes Management, Mostafa Abdelaziz, Amr Refaie

Mechanical Engineering

Diabetes mellitus patients must regularly monitor their blood glucose levels to manage glycaemia, typically requiring capillary tests at least three times daily and laboratory tests one to two times per month. These conventional methods involve finger pricking, causing significant discomfort and stress. This study introduces an innovative non-invasive glucose monitoring approach by integrating photoplethysmography (PPG) technology with an artificial intelligence (AI) algorithm, complemented by a mobile application using Flutter, IoT systems, and Firebase cloud for real-time data access. Among the AI models tested, polynomial regression demonstrated superior accuracy in glucose prediction, achieving a Mean Squared Error (MSE) of 14.76 and …

Comparative Analysis Of Electrode Encapsulation Reliability: Planar Vs. Thermoformed Interdigitated Neural Electrodes In Biomedical Engineering, Tatum Peyerl

Graduate Theses, Dissertations, and Problem Reports (ETD)

Durable dielectric encapsulation is crucial for the long-term function of implantable neural electrodes; however, the reliability of curved, thermoformed coatings remains underexplored. This study addresses that gap by comparing planar (non-thermoformed) and thermoformed interdigitated neural electrodes (IDEs) encapsulated in Polyimide-2611. Both device types underwent accelerated in vitro aging in phosphate‑buffered saline (PBS) at 67 °C for approximately 91 days, simulating two years of physiological exposure. Post-accelerated aging evaluation included electrochemical impedance spectroscopy (EIS) from 0.1 Hz to 100 kHz to monitor moisture‑induced leakage, and high‑voltage breakdown testing under saline immersion to assess dielectric strength. After aging, all electrodes maintained impedance …

An Analytical Model Of Motion Artifacts In A Measured Arterial Pulse Signal—Part I: Accelerometers And Ppg Sensors, Md Mahfuzur Rahman, Subodh Toraskar, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

This paper, the first of two parts, presents an analytical model of motion artifacts (MAs) in measured pulse signals by accelerometers and photoplethysmography (PPG) sensors. As the transmission path from the true pulse signal in an artery to the sensor output (measured pulse signal), the tissue-contact-sensor (TCS) stack is modeled as a 1DOF (degree-of-freedom) system. MAs cause baseline drift of the mass and simultaneously time-varying system parameters (TVSPs) of the TCS stack. With arterial wall displacement and pulsatile pressure serving separately as the true pulse signal, an analytical model is developed to mathematically relate baseline drift and TVSP to a …

Robust Quantification Of Cortical Hemodynamic Response To Tactile Stimulation: A Comprehensive Fnirs Methodology To Mitigate Physiological Confounds, Mohsen Hozan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation establishes a quantitative framework for studying somatosensory processing using functional Near-Infrared Spectroscopy (fNIRS), with a focus on applications in neurorehabilitation. The central aim is to investigate how the brain's hemodynamic response is modulated by the velocity of patterned tactile stimulation. While fNIRS is a promising neuroimaging tool, its data quality is often compromised by physiological noise and motion artifacts, challenging the reliability of its findings and hindering the development of effective, quantifiable neurotherapeutics.

Two preliminary investigations informed the final experimental design. The first pilot study confirmed that pneumotactile stimulation of the hand, during both passive (somatosensory) and active …

Cochlear Electrode Insertion Training Model, Sarah Powell, Kaelyn E. Kraley, Nathan J. Smith

Williams Honors College, Honors Research Projects

Cochlear implant surgery is a delicate procedure performed by Otolaryngologists (ENTs) to implant an electronic device into the inner ear to provide a sense of sound for people who are profoundly deaf or hard of hearing. The current practices of training involve cadavers and 3D-printed models. Cadavers are commonly used but are expensive, single-use, and do not provide visual and haptic feedback, which are essential for medical students. 3D printed models are less commonly used and are hard to fabricate and not as realistic. If medical students are not properly trained for this delicate procedure, then risks are significantly increased …

Delivery Method For Dissolvable Staples, Brian Nguyen, Colleen Kroah, Bethany Fogle, Sean Brown

Williams Honors College, Honors Research Projects

Surgical staples play a vital role in modern medicine by enabling efficient wound closure and tissue repair. However, traditional metal staples often require removal, increasing patient discomfort and the risk of infection. Dissolvable staples offer a promising alternative, eliminating the need for removal while maintaining secure wound closure. Despite their potential, current delivery systems for dissolvable staples face significant challenges, including inconsistent deployment, lack of precision, and inadequate integration with surgical workflows.

Developing an optimized delivery system is critical to maximizing the benefits of dissolvable staples. Such a system must ensure reliable performance, precision, and ease of use while maintaining …

An Improved Method To Protecting Skin Graft Dressings Following Surgery In Severe Burn Patients, Andrew Martin, Matt Flaker, Hailey Essinger

Williams Honors College, Honors Research Projects

Severe burns, including deep second- and third-degree burns, affect over 450,000 people annually in the U.S., often requiring skin grafts for treatment. Recovery involves wearing wound dressings covered by bandage wraps for at least two weeks. While wraps are breathable, versatile, and simple, they can be painful to apply, especially for larger patients, and their compression varies based on the person applying them. This poses challenges when untrained caregivers are involved. Additionally, wraps often slip during physical therapy. Burn care units seek a new solution that matches current wraps in breathability and comfort but offers quicker application, controlled compression, and …

Investigation Using Single Point Incremental Forming (Spif) To Fabricate Patient-Specific, Titanium Orbital Floor Implants, Elizabeth M. Mamros, Lauren E. Blaha Md, Christian A. Kauffman Md

Faculty Conference Papers and Presentations

The floor of the human orbit is composed of thin bone that is prone to traumatic fracture. This leads to a loss of support for the eye, which can cause vision changes. Therefore, fractures may need surgical reconstruction using a thin, sheet-like implant. Titanium implants are available off-the-shelf in standard sizes, but fitting to each patient’s unique anatomy requires surgeons to cut, file, and bend these plates. This can be time-consuming and imprecise. To both save time and ensure a perfect fit for the patient, a custom plate can be created prior to surgery. This investigation focuses on single-point incremental …

Adaptation Of The Biodent For Spherical Microindentation To Determine Elastic Modulus In Small Rodent Bones, Mixame E. Jerome

Dissertations and Theses

Mechanical and material properties of bone are essential for understanding both normal skeletal function and the progression of bone-related diseases. Microindentation has become a widely used method for evaluating tissue mechanical properties of bone, as it samples the contributions of microarchitecture and composition. Microindentation using a standard pointed tip inherently introduces both elastic and plastic deformation into the material. In contrast, indentation with a spherical tip can be operated entirely in the elastic range, providing for a non-damaging test that has significant advantages over sharp indentation techniques. Moreover, a key advantage of using spherical indentation lies in its operation under …

Advancing Electrical Stimulation: Full-Head Mri Segmentation For Abnormal Brain Anatomy With Tdcs, Andrew Birnbaum

Dissertations and Theses

Evaluating the effectiveness of transcranial direct current stimulation (tDCS) is essential for guiding its integration into therapeutic and performance-enhancement applications. In our laboratory, we investigate the efficacy of tDCS across multiple experimental models, including both animal and human studies. I have contributed significantly to the execution and analysis of these experiments, which include studies in rats and healthy human participants aimed at evaluating whether electrical stimulation of the motor cortex can enhance motor learning. These studies assess improvements in fine motor performance resulting from tDCS. In stroke patients, I contribute to our investigation of tDCS as a rehabilitative intervention, particularly …

Wearable Disposable Elecetrotherapy, Mohamad Fallahrad

Dissertations and Theses

Non-invasive electrotherapies offer promising treatments for a wide range of conditions such as pain, headaches, depression, addiction, cognitive decline, wound healing, and drug delivery. However, patient compliance remains low due to the high initial cost, cumbersomeness and inconvenience of existing technology compared to pharmaceuticals. Current electrotherapy devices are often bulky and require users to connect disposable electrodes, initiate programs, and manage charging cycles, which hinders widespread adoption.

We address these challenges by designing and validating a novel electrotherapy platform that is single-use, disposable, low-cost, and wearable. Activated automatically upon skin contact, the device delivers a preset dose of controlled electrical …

Interfacing Neural Models: Biocompatibility And Fabrication Of A Flexible, Self-Folding Microelectrode Array, Fernando A. Pesantez Torres

Electronic Theses & Dissertations (2024 - present)

Neurodegenerative diseases pose a formidable challenge in modern medicine, necessitating the development of advanced research tools that can elucidate their complex pathophysiology. Recent advancements in neurodegenerative disease research have led to the development of three-dimensional (3D) neurodegenerative organoids using human induced pluripotent stem cells (hiPSCs). These organoids closely mimic human brain architecture and functionality, providing a valuable tool for understanding complex diseases. Additionally, the ability to generate and study brain organoids consistently and in large quantities holds potential for a controlled in vitro setting and high-throughput drug screening. However, these models are complex systems requiring specialized maintenance, analysis, and manipulation …

Online Parameter Adaptation Of Lqr Controllers Via Rls For Prosthetic Joint Control: Experimental Validation On A Quanser Qube-Servo 2 Platform, Cynthia Lopez-Jordan

Theses and Dissertations

This thesis develops and experimentally validates an online adaptive Linear Quadratic Regulator (LQR) control method for prosthetic joint systems using Recursive Least Squares (RLS)-based real-time parameter estimation on the Quanser QUBE-Servo 2 platform. Traditional LQR controllers assume a fxed system model, which limits adaptability and results in reduced tracking accuracy, poor robustness, and loss of optimal performance when applied to dynamically changing prosthetic joints, infuenced by load variations, user gait changes, and mechanical wear. Limited experimental validation exists for combining RLS with online LQR adaptation in prosthetic-like systems.

To address these limitations, an RLS-driven Adaptive LQR framework was implemented to …

Laser-Induced Graphene For Early Disease Detection: A Review, Sri Ramulu Torati, Gymama Slaughter

Center for Bioelectronics Publications

Electrochemical biosensors have been instrumental in early disease detection, facilitating effective monitoring and treatment. The emergence of graphene has significantly advanced sensor technology in various fields, including biomedicine, electronics, and energy. In this landscape, laser‐induced graphene (LIG) has emerged as a superior alternative to conventional graphene synthesis methods. Its straightforward fabrication process and compatibility with wearable devices boost its practicality and potential for real‐world applications. This review highlights the transformative potential of LIG in biosensing, showcasing its contributions to the development of next‐generation diagnostic tools for early disease detection. An overview of the LIG synthesis process and its applications in …

Finite Element Modeling And Experimental Characterization Of Overmolded Gold-Palladium Composite Leads And Their Mechanical Behavior Under Cyclic Fatigue For Long-Term Implant Applications, Tanner Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Auditory Nerve Interface (ANI) devices, currently in developmental stages, represent an emerging neuroprosthetic approach to restore hearing in severe sensorineural loss patients by directly stimulating the auditory nerve via the Utah Slanted Electrode Array (USEA). Conventional implant leads are comprised of multiple wires made from materials such as platinum-iridium and MP35N stainless steel that are overmolded in an insulative material. These materials are not possible to bond with to electrode array used in the ANI device, necessitating the evaluation of a new material like Au-Pd to ensure its functionality and durability under cyclic stresses. This gap necessitates characterization of alternative …

Microwell Fabrication For Impedance And Ac Measurements Of Isolated Ventricular Cardiomyocytes, Fallon Wenck

Multidisciplinary Studies Theses and Dissertations

Electrophysiological behavior of human hearts have been extensively studied for hundreds of years. Even with elucidation of not just biological function, but also time and frequency-dependent current flow, the sheer intricacy of in vivo cardiac tissue function remains somewhat enigmatic. All while heart disease has been the leading cause of death in the United States for over a century, with its rates of occurrence still increasing annually [1]. Thus, new research techniques and tools to quantify cardiac function are still being pursued at smaller and smaller scales to decrease research/innovation time, cost, and diagnostic ambiguity. In fact, it remains incredibly …

Development Of A Pressure Sensing System Coupled With Deployable Machine Learning Models For Assessing Residual Limb Fit In Lower Limb Prosthetics, Maxwell D. Lewter

Master's Theses

Lower limb amputations pose significant challenges for patients, with over 150,000 cases annually in the U.S., leading to a high demand for effective prosthetics. However, only 43% of lower limb prosthetic users report satisfaction, primarily due to issues with socket fit, which is critical for comfort, stability, and preventing injury. This study presents a deployable sensing system for potentially real-time monitoring of prosthetic socket fit by using pressure sensors and convolutional neural networks (CNNs) to analyze the pressure distribution within the socket. A novel CNN architecture, utilizing both dilated and strided convolutions, is proposed to effectively capture spatial-temporal patterns in …