Biomedical Devices and Instrumentation Commons^™

Hypoxic Incubator: Improving Robustness/Reliability And Demonstrating Physiological Efficacy, Damon Dennis Tan

Master's Theses

The Microphysiological Systems Laboratory aims to develop colorectal cancer tumor models under a hypoxic environment to assess model response to pharmaceutical compounds in vitro. To perform relevant studies, researchers have attempted to use different hypoxic inducing strategies such as a nitrogen pod and hypoxic incubator to recreate in vivo physiological responses to hypoxia. However, studies would be interrupted due to incubator functionality failure. To ensure successful and physiologically relevant studies, I improved and verified the robustness and reliability of a hypoxic incubator previously designed and manufactured in the lab. Through the testing and iterating design processes, I engineered and implemented …

Dual Base Sige Is-Hbt For Use In Biosensing Applications, Liam Stephen Hayes

Master's Theses

The proposed research is for a novel SiGe-based Ion-Sensitive Dual Hetero-junction Bipolar Transistor (IS-HBT) to be used in both trans-dermal biological sensing as well as Lab-on-Chip (LOC) applications. The end goals for the device designed are two: For one, the research done for this work will be used to substantiate the claims made by Zafar et al. [1] that an HBT-style structure is better suited for biosensing application rather than a conventional Field Effect Transistor (FET) based geometries. Secondly, it provides the final element to be integrated along with a selectivity membrane, as well as with a reverse-iontophoresis system to …

Nasogastric Tube Insertion Aid, Lauren S. Ark, Angela D. Biezins, Zachary B. Crum, Claire E. Nodine, Morgan N. Pope, Natsumi L. Shudo

Biomedical Engineering

The Nasogastric Tube Insertion Aid project, developed under the sponsorship of the BiCEP Program at California Polytechnic State University, aims to enhance the accuracy and efficiency of nasogastric (NG) tube placement. This initiative was inspired by challenges observed during the BiCEP summer program, where difficulties in NG tube insertions led to multiple attempts, increased patient discomfort, and serious medical risks, including lung punctures and brain trauma. The project's goal was to design an insertion aid that improves placement accuracy while being cost-effective and user-friendly for medical professionals. The device features an external tensioning mechanism that allows controlled deflection of the …

Development Of An Advanced Step Counting Algorithm With Integrated Activity Detection For Free Living Environments, Paige M. Dolan

Master's Theses

Physical activity plays a crucial role in maintaining overall health and reducing the risk of various chronic diseases. Step counting has emerged as a popular method for assessing physical activity levels, given its simplicity and ease of use. However, accurately measuring step counts in free-living environments presents significant challenges, with most activity trackers exhibiting a percent error above 20%. This study aims to address these challenges by creating a machine learning algorithm that leverages activity labels to improve step count accuracy in real-world conditions. Two approaches to balancing data were used: one employed a simpler oversampling technique, while the other …

Thermal Preconditioning Effects On Perforation Propensity Of Transvenous Implantable Cardiac Leads Used For Pacing And Defibrillation, Diane Muff

Master's Theses

Thermal preconditioning to simulate shipping, handling and storage conditions did not affect distal tip stiffness values for permanently implantable cardiac leads used for pacing and defibrillation. Leads that were subjected to extreme temperatures and temperature cycling did not show changes in buckle force values compared with control specimens which were maintained at ambient room conditions. Absolute differences between all measurements were small, generally under 0.05 N and were attributable to measurement variability.

Buckle force values are used to assess the propensity of leads to perforate the heart, a rare but potentially serious complication of implantable pacing and defibrillation systems. Since …

Smart Cushion Device For Elderly Aging In Place, Anna Dion, Nate Colley, Leonardo Bravo

Biomedical Engineering

Our task at hand is to develop a consumer-focused solution for improving elder care to provide additional peace of mind for seniors and caregivers using technology to extend independent living. We intend to create a device that will improve the quality of life of elderly individuals living alone by encouraging periodical movement throughout the day, along with monitoring pressure distribution and alerting when pressure concentration is potentially harmful. It will also alert users to the presence of moisture which can arise from spills or incontinence. The key stakeholders of this project include elderly adults over the age of 65 who …

Bolin Symes Prosthetic, Samuel C. Collins, Rowan Sun, Jake Hacker

Biomedical Engineering

This project’s purpose is to design a comfortable prosthetic for an individual with a Syme’s amputation, which is a below-knee amputation that removes the foot from the leg at the ankle joint. The goal is to minimize the discomfort that is associated with the current prosthetic leg options for the client, Mr. Bolin, who has the Syme’s amputation. This project also seeks to improve mobility, quality of life, and activity levels of the client. The stakeholder for this project is Mr. Bolin. The final prototype performed successfully when worn by the client and passed comfort testing. Furthermore, COMSOL modeling of …

Deep Vein Thrombosis Diagnostic Device, Alisha Mitha, Karina Martel, Ayla Silbahar

Biomedical Engineering

Deep Vein Thrombosis is one of the leading causes of death in hospitals worldwide due its ability to form in patients who are sedentary after receiving care. There is a need for a DVT diagnostic device that can be worn constantly in order to alert medical professionals if a thrombosis is forming, which is the basis of this senior project. The current solutions are time consuming, and look for thrombi after they have fully formed. The goal of this senior project is to design and construct a device to constantly monitor in-hospital patients for early stage DVT and alert hospital …

Liftwalker, Kai A. De La Cruz, Lexie Caterine, Adam Monroe, Jame Whealan

Mechanical Engineering

The LiftWalker’s purpose is to lift users with degenerative diseases from a seated to standing position and support them as they practice the motion of walking as a form of physical therapy. The current LiftWalker is upward of $5,000 so we redesigned the LiftWalker to be more accessible around the world. This meant using affordable and accessible materials and manufacturing processes. To achieve this, we made our design mostly out of bike parts and off-the-shelf components. When it came to the lift system, we found that to maintain a safe and comfortable design it was best to purchase a trailer …

Kinomatic Hip Arthroplasty Pelvic Tilt, Emily Wolfert, Teddy Alberton, Sydney Dresser

Biomedical Engineering

Kinomatic is a startup company that provides custom preoperative surgical plans for orthopedic surgeons. The surgical plans are intended for total hip and knee arthroplasty to provide patient-specific measurements and implant sizing. Surgeons can view the surgical plans as 3D models in virtual reality with an Oculus Quest 2 headset or as a PDF summary. Most patients receive a diagnostic anterior-posterior (AP) x-ray that allows their surgeon to determine if they are eligible for a total hip or knee replacement. After diagnosis, the patient can also choose a Kinomatic surgical plan to provide their surgeon with additional data points before …

2-Channel Eeg Neurofeedback System, Tim Erwin, Donna Nikjou, Sebastian Turkewitz

Electrical Engineering

This work describes the design of an EEG-based neurofeedback system which provides users with real-time feedback on their level of focus or relaxation. By analyzing the spectral content of the brain activity measured via scalp electrodes, focus and relaxation levels can be quantified. Based on these measurements, live feedback in the form of moving bar graphs is provided to users, allowing them to gain awareness of their mental-state and more efficiently learn how to consciously relax or focus. This project covers the design of the system, including amplification and filtering stages, digitization, and signal processing. The system interfaces with a …

Manufacturing Silicone In-House For The Creation Of Customized Neurovascular Blood Vessel Mimics, Jacob Wilbert Perisho

Master's Theses

The Tissue Engineering Lab at California Polytechnic State University San Luis Obispo focuses on creating tissue-engineered Blood Vessel Mimics (BVMs) designed for the preclinical testing of neurovascular devices. These BVMs are composed of silicone models, representing anatomically accurate neurovasculatures, that are sodded with vascular cell types and then cultivated in bioreactors (which maintain physiologic conditions). These silicone models are currently sourced externally from industry partners, so the primary goal of this thesis was to develop the means and methods for the Tissue Engineering Lab to manufacture silicone models in-house.

The first aim of this thesis was to develop and explore …

Development Of An In Vitro 3-Dimensional Co-Culture Human Colorectal Cancer Model In Microfluidic Devices, Abby Jens

Master's Theses

Colorectal cancer is the second most common cause of cancer-related deaths in the United States, with the relative 5-year survival rate for distant stage cancer being only 14%. The most common treatment for colorectal cancer is with chemotherapeutic drugs; however, the discovery of these drugs is costly, time-consuming, and often requires the use of animal models that do not yield results that translate to clinical trials. Due to these shortcomings, researchers seek to develop physiologically relevant in vitro tumor models that more accurately mimic the tumor microenvironment for cheaper and faster high-throughput drug screening. The aim of this research was …

Development Of A Cell Culture Incubator Capable Of Providing A Hypoxic Environment, Grant Austin Coe

Master's Theses

In order to perform more robust and physiologically relevant research, the Microphysiological Systems laboratory required a method of culturing cells where the level of oxygen could be adjusted. To fulfill this need, I designed and manufactured a hypoxic cell culture incubator. I employed a Quality Function Deployment to understand the customer requirements and convert them into engineering specifications. Based on these specifications, I created various conceptual designs. I evaluated the conceptual designs as compared to existing products and decided to move forward with the control system separated from a small, standard chamber. I developed the circuitry schematics for the temperature …

Tourniquet Pressure Gradient Measurement Apparatus, Luis Enrique Perez, Elsa Elizabeth Bates

Biomedical Engineering

The goal of this project was to design a device that would measure pressure gradient data across the width of an elastic and inelastic tourniquet cuff using a human limb model. The main customer requirements that were focused on were to accurately measure the pressure from a tourniquet, keep the cost down, and be easy to use. The targeted design specifications were to read pressure values ranging from 0-400 mmHg, keep the test length under 5 minutes, and to keep the cost of materials under $400. The design of the device ended up consisting of 5 IV pouches that were …

Finite Element Analysis Of The Bearing Component Of Total Ankle Replacement Implants During The Stance Phase Of Gait, Timothy S. Jain

Master's Theses

Total ankle replacement (TAR) implants are an effective option to restore the range of motion of the ankle joint for arthritic patients. An effective tool for analyzing these implants’ mechanical performance and longevity in-silico is finite element analysis (FEA). ABAQUS FEA was used to statically analyze the von Mises stress and contact pressure on the articulating surface of the bearing component in two newly installed fixed-bearing total ankle replacement implants (the Wright Medical INBONE II and the Exactech Vantage). This bearing component rotates on the talar component to induce primary ankle joint motion of plantarflexion and dorsiflexion. The stress response …

Assisted Delivery Device, Rachel Rowe, Madeliene Mumford, Jenna Eissmann, Brittany Trinh

Biomedical Engineering

Current devices used to assist in complicated births present serious risks to both the mother and the fetus, which has caused a decline in the use of these devices over the last decade. This senior project team has proposed an alternative device that interfaces with the infant’s shoulders that would decrease these risks and contribute to the decrease of unnecessary c-sections due to device inadequacy. This Statement of Work includes research on the downfalls of current devices, existing patents, customer requirements, engineering specifications, and a design plan through December of this year. The next phase of this project will include …

Neonatal Respiratory Therapy Interface, Kennedy Austin, Evan Manley, Parker Murray, Harrison Oen

Biomedical Engineering

This Final Report reviews and outlines the scope, objectives, and deliverables for the BCPAP Interface Redesign project, aimed at enhancing the functionality, usability, and patient experience of the existing BCPAP interface. It also includes detailed testing results and manufacturing plans for the device prototype. The current system has challenges in universal usability, time constraints, and patient comfort, which this project intends to address effectively. The goal of this project is to reevaluate and redesign the interface of the bubble continuous positive air pressure (BCPAP) machine’s attachment site with the infant. Due to the millions of premature neonates and thousands of …

Effects Of Beet Supplements On Cardiovascular Response Using A Noninvasive Blood Pressure Cuff, Nicholas M. Hughes

Master's Theses

A Calibrated Cuff Plethysmography device was built, tested for verification, and used to experiment on human subjects to measure the cardiovascular response of consuming a beet supplement, specifically looking at arterial compliance and pressure-area curves. Each subject was tested four times. A baseline was measured under normal conditions and after five-minute hyperemia conditions. 10 subjects were given 6 ounces of water mixed with either purple Kool-Aid (control), a SuperBeets supplement, or a SuperBeets Sport supplement and after 45 minutes, measurements were taken undergoing normal and hyperemia conditions once more. The verification testing demonstrated the calibration of the device was effectively …

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian

Biomedical Engineering: Graduate Reports and Projects

As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological …

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian

Master's Theses

As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological …

Time-Lapse Imaging Of Colorectal Cancer Tumors, Jasmeet Sandhu

College of Engineering Summer Undergraduate Research Program

This project was aimed to test and validate a newly constructed live-cell imaging system that allows for imaging and live cells and tissues. This system is comprised of an incubation chamber that controls that temperature and pH of live cell culture while on a microscope.

Static Vascular Modeling Of Diabetes Progression, Andrea Skattenborg

Master's Theses

Cardiovascular disease is the leading cause of mortality in diabetic patients, and diabetes is one of the main causes of cardiovascular disease. Risk factors for cardiovascular disease result in structural and functional changes in the vascular wall. Arterial stiffness is a prominent structural change observed in the arterial wall that can be measured in clinical settings. The purpose of this thesis was to create a static model of the changes in arterial stiffness seen in diabetes. Elastic tubes with varying wall thicknesses were used to create artificial arteries for this purpose. Compliance (inverse of stiffness) of the arteries was determined …

Analytical Pipeline To Facilitate Electroencephalography Pain State Identification In Patients With Chronic Low Back Pain, Emma Katharina Jacobs

Master's Theses

Chronic low back pain (cLBP) affects the quality of life of over 23% of American adults and places an immense burden on the economy.^1–3 To more effectively diagnose and treat cLBP, quantitative biomarkers are needed to objectively measure pain and better identify the underlying mechanisms of cLBP. The overarching goal of this work is to create an analytical pipeline to investigate brain activity patterns measured with electroencephalogram (EEG) data of cLBP patients treated with transcutaneous spinal cord stimulation (tSCS). The specific aims of this project are to 1) investigate whether there is a difference between baseline EEG measurements and …

Analysis Of Arterial Compliance Using A Surrogate Arm Bench Top Model For The Validation Of Oscillometric Blood Pressure Methods, Christopher J. Cunningham

Master's Theses

A study was performed on a recently developed prototype of the Yong-Geddes surrogate arm design to collect compliance data of the various system components and determine the accuracy of measurements made through the bench top model. The study was performed to perceive the effectiveness of the model as a tool for validating non-invasive blood pressure detection monitors. Three stages of testing were performed to gather pressure and volume data from an artificial artery component, a sphygmomanometer, and the surrogate arm system to produce compliance estimations. Mathematical equations from supported arterial hemodynamics studies and clinical trials were applied to the pressure …

Bruxism Biofeedback Device, Claire A. Dossey, Errin S. Abasolo, Isabelle A. Starr

General Engineering

This paper aims to summarize the design process for a biofeedback bruxism device, covering the necessary background research, engineering requirements, design process, prototyping, manufacturing, and testing for the device. The purpose of this project was to design an engineering solution for the treatment of bruxism. This entails both measuring and significantly reducing clenching and grinding during sleep, as many current solutions may reduce symptoms of the disorder, but do not treat bruxism itself. Engineering requirements included biocompatibility, size and weight, electrical safety, and easy of use and comfort. Many design options were proposed, and a Pugh Matrix was used to …

Biomechanical Knee Joint For Exoskeleton, Gabriel Ireton Ahern, Calloway Miller, Christianna Altamura, Eric Mailes

Mechanical Engineering

Our senior design project consisted of designing and manufacturing a biomechanically accurate, actuated knee joint to be integrated into an exoskeleton being developed by the Lower Limb Exoskeleton Assist Project (LLEAP), a part of the EMPOWER student association at Cal Poly, San Luis Obispo. As the human knee flexes and extends throughout gait motion, the center of rotation changes. Currently marketed exoskeletons have one point of rotation, which over constrains the knee and causes misalignment between the user and the suit [1]. Our goal was to mimic natural knee joint motion by changing the center or rotation, thus reducing misalignment …

Postpartum Hemorrhage Detection Device, Kaitlyn Bailey, Adrian Diaz, Alcides Caballero

Biomedical Engineering

During a cesarean section, blood loss greater than 1000 mL is classified as a hemorrhage. Quantified blood loss methods are used to detect hemorrhage, however existing methods are inaccurate and time consuming. Our proposed device is inserted vaginally during a cesarean section to collect and quantify blood lost via the cervix during and after the procedure. The device also applies light suction to the uterus, which can aid in uterus collapse and decrease the risk of postpartum hemorrhage.

Gait Analysis Device For Elderly Fall Prediction, Ryan Hahn, Claudia Miller, Evan Yakligian

Biomedical Engineering

This document serves to outline the design process and final design for our project to address elderly independent living in collaboration with Apple. Included in this document is necessary academic literature of current fall risk assessments and descriptions of the current market of wearable gait analysis devices. Based on this research and data, we then outline a plan for design, manufacturing, prototyping, and testing a device to fulfill the original prompt given by our sponsors: create a device that will increase the ability of an aging loved one to live at home safely. This device is a wearable that collects …

Hypoxic Incubation Chamber, Simone Lisette Helfrich, Makenzie Nicole Jones

Biomedical Engineering: Graduate Reports and Projects

This paper describes the design, manufacturing, and testing of a novel controllable hypoxic incubator with fully functional oxygen gas control and temperature control in a humid environment. On the current market, a majority of the few hypoxic incubators use pre-mixed gas that does not offer precise control over gas concentration. The objective for this project was to create a chamber that allows the user to set the O2 concentration to varying set points of % O2 while maintaining the chamber at a constant body temperature, CO2 level, humidity, and sterility. To start the project, multiple concepts were developed for the …