Wood is a fundamental material in various industries, from construction to furniture making. Understanding its mechanical behavior is crucial for optimizing its use and ensuring structural integrity. This study investigates six different wood types under flexural loading, offering insights into their performance in real-world applications. By analyzing key parameters such as density, flexural strength, and stiffness, this research aims to provide valuable data for informed material selection and design optimization. The wood types under scrutiny comprise white oak, birch, bamboo, maple, pine, and walnut with two contrasting grain configurations.

Key parameters: Density, Flexural Strength, Flexural Stiffness

Effective disinfection of medical surfaces is crucial in preventing healthcare-associated infections. The objective of this study was to compare two techniques for transferring bacteria, specifically Staphylococcus epidermidis, from contaminated medical surfaces to agar plates for growth assessment. The first technique involved imprinting the contaminated surface directly onto the agar plate, while the second technique utilized a sterile swab to pick up bacteria and transfer them to the agar plate. Results indicated a significantly higher percentage of bacterial transfer using the imprint technique compared to the swab technique. Consequently, the imprint technique was selected for further investigation to quantify results related to the disinfection of contaminated medical surfaces. This study underscores the importance of selecting appropriate bacterial transfer techniques for accurate assessment of surface disinfection efficacy in healthcare settings.

The two-microphone impedance tube test method is a well-established and widely used technique for determining the acoustic absorption coefficient and impedance ratio of materials. This method uses two closely spaced microphones to simultaneously measure the incident and reflected sound waves. A two-microphone impedance tube measurement system made of 6061-T6 Aluminum with a diameter of 3 inches, a 0.5 inch wall thickness, and microphones spaced 2.7 inches apart has been constructed for undergraduate research at Texas Christian University (TCU). These geometrical values suggest a usable frequency range of 50 Hz to 2637.77 Hz as referenced in ASTM Standard E1050-19. Validation of the system was achieved by taking measurements on Owen Corning Type 705 pressed fiberglass board with a 1-inch thickness and comparing them to absorption data provided by the manufacturer. Additional validation measurements were taken without a test sample in place. All validation tests suggest that the TCU impedance tube is an accurate measurement system.

Bacteria, the primary agents of infection in humans, are present on nearly all surfaces. To mitigate the spread of bacteria and infections, disinfectants are commonly used. This study explored the effectiveness of common disinfectants and different methods of disinfection, primarily focusing on the use of spray pumps and a transducer as a mechanism to disinfect surfaces using 70% IPA (Isopropyl Alcohol) or ethanol (often referred to by the brand name Lysol). Tests were conducted on bacterial lawns before incubation. The effectiveness of the tests was determined by observing bacterial growth over the next 24 hours after disinfection. Testing proved that both ethanol and 70% IPA are effective in stopping bacterial growth. While both the transducer and spray pump methods showed success, the transducer/ethanol combination was particularly efficient, using the least amount of disinfectant.

Thermal oxidation is an important process to create a thin film of silicon dioxide on silicon substrates in microfabrication. In this project, thermal oxidation characteristics on the silicon wafer will be analyzed through experiments in the clean room. The research method was conducted in the thermal oxidation furnace in the TCU Cleanroom on nine wafers with different placement orientations in the furnace and three different oxidation temperatures: 950°C, 1000°C, and 1050°C. In addition, oxide thickness measurements between different locations on the wafer were taken to investigate the film uniformity. The data analysis showed three trends: 1. oxide thickness varies across the wafers, 2. oxide thickness varies as a function of the furnace location, and 3. oxide growth rate varies as a function of furnace temperature. This project investigates how these factors impact thermal oxidation, one of the most critical steps in microfabrication

The Digital Micro-Mirror Device (DMD), which was originally developed for digital projection using visible light source, has seen numerous applications in automotive, manufacturing, spectroscopy, and underwater imaging that require wavelength beyond visible. The DMD window is an important part of the packaging that protects the digital mirror array. Since the light goes through the top and bottom surfaces of the window glass twice during operation, the transmittance of the window is usually optimized for the range of wavelengths specified by the applications through optical coatings. In this research work, we will explore the effectiveness of the optical coatings for different types of glasses for window transmittance improvement in visible and near-infrared wavelengths. We will evaluate the transmittance of the existing DMD window glasses and explore ideas of improving transmittance in the NIR range without compromising the effectiveness in the visible light range. In doing so, we would be the light efficiency of the DMD in a wider wavelength range.

This research focuses on developing an optical metrology system to characterize the 3D refractive index profile of intraocular Lenses (IOLs) and contact lenses. Recent innovations in IOLs and contact lenses have facilitated the creation of lenses with finely controlled refractive index gradients across their surfaces, and as a result, the demand for precise metrological techniques has increased. Optical Phase Computed Tomography (OPCT) holds as a possible method for precisely characterizing these gradients. OPCT operates on the principle of the parallel ray approximation, which assumes that the rays passing through a surface remain unaltered in angle and continue parallel. OPCT has proven effective in determining the refractive index of optical fiber, this success can be attributed to the minimal deviation from parallel ray assumption of the optical fiber. This study aims to ascertain the feasibility of using OPCT for the characterization of intraocular lenses (IOLs) and contact lenses. Our approach involves replicating, through simulation, the previously studied optical fiber to determine the maximum deviation angle from the parallel ray assumption. Utilizing simulated models of IOLs and contact lenses, we investigate the repercussions of deviations from the parallel ray assumption on OPCT precision. We aim to compare these findings to the established deviation observed in fiber optic studies. This comparative analysis will offer insights into the potential applicability of OPCT for IOLs and contact lenses, allowing for further development of enhanced optical metrology techniques.

Effectiveness and Efficiency of UV-C Lights at Killing Bacteria:

Bacteria lie on surfaces all around us, resulting in a desire to clean or disinfect them to avoid the adverse effects of bacteria. One popular method is UV-C light, which has a wavelength of 200-280 nanometers. This study aimed to determine the effectiveness of UV-C lights in killing bacteria. Tests were conducted using a power sensor and bacterial lawns to determine the impacts of different variables on the effectiveness of UV-C lights. Testing measures were taken to ensure that all data was collected independently and identically. It was found that height, surface placement under UV-C lights, electrical power to lights, and reflectivity had the most significant impact on the effectiveness of the light. When optimizing these variables, it was found that with three and two lights there was a substantial bacteria kill rate once the exposure exceeded 3 seconds. This study has proven that UV-C is an effective and efficient way to kill bacteria on surfaces.

This project delved into the multifaceted world of blacksmithing, merging scientific inquiry with traditional craftsmanship to understand the nuances of metal work and material sciences. The primary objective was to immerse in the practicality of the craft, with the intent of learning the use of essential tools, the operational aspects of a forge, and further developing my knowledge of material properties of metals. In the aspect of material properties, a target was made to cultivate a comprehensive understanding of the manipulation of metal properties, utilizing heat treatment, cooling, and knowledge of metallurgical behavior.

Key milestones were set, including the acquisition of competencies in manipulating metal through heating, working, and cooling to craft rudimentary objects like hooks and nails, progressing towards more intricate creations such as knives and ornamental ironworks. The project's methodology was twofold: an investigative theoretical approach entailing the study of literature and visual resources to build a foundational knowledge base, and an empirical approach through active participation in local blacksmithing workshops.

The culmination of the project saw the successful completion of a functional coat rack and a knife forged from a railroad spike, reflecting both the learned techniques, material science, and personal creative expression. The analytical engagement with metals and forging methods paved the way for producing personalized, high-quality metalworks. The endeavor not only honed a distinctive skillset but also unveiled the potential for a post-graduate entrepreneurial venture specializing in custom-made tools and decorative arts, thereby intertwining the art of blacksmithing with contemporary business opportunities.

Power quality is the compatibility between the voltage that comes out of an electrical outlet and the power load that is being plugged into it. A power load (also known as electrical load) is any electrical device that needs to be plugged into a larger power grid to run, such as televisions and microwaves.
Different devices require different power loads to run at full efficiency and while electrical systems are capable of handling newer power loads, they are currently set to work with older ones as well. This may cause some side effects on power quality in the system. In this project, we investigate how to improve the power quality in the system caused by an inductive older load.

A Faraday cage is an enclosure that shields electromagnetic fields from entering or exiting the cage. While metals with high electrical conductivity are expected to effectively demonstrate the operation of a Faraday cage, preliminary observations of a sealed cast iron cylinder allowing the transmission of Bluetooth signals between a smartphone and wireless earbuds across it suggested the need for further research into electromagnetic wave propagation through closed metal systems. This research utilized Bluetooth connectivity tests through sealed metal cylinders made of cast iron, aluminum, and stainless steel to analyze the working of Faraday cages, explore related material properties, and isolate possible reasons for the conflict in expected behavior when electromagnetic transmission is detected through such cages. The research methods included conducting Bluetooth connectivity tests with different cylinder orientations and analyzing the strength of the transmitted and received Bluetooth signal. The key findings of this study suggest that material properties, spatial orientation, and the strength of the electromagnetic source influence the transmission of electromagnetic waves through sealed metal cylinders. The implications of these findings suggest potential exceptions to a common electromagnetic phenomenon and provide insights for future research.

Texas Instruments is developing a new micro-optical-electro-mechanical device called phase light modulator (PLM). The TCU senior design team developed a robust testing system that can expose 20 PLM devices to different light sources with the capability of monitoring the temperature and light intensity at each device location. The system design and construction of the testing system will be presented. In addition, the selection and operation of LEDs, temperature and light sensors, as well as the optical components that are needed for the light source and sensors will be discussed.

DC to DC Conversion is important in modern electronics, and to the automotive industry. It is the process of converting a direct current (i.e constant) signal into another form of direct current (DC). A small-scale example of this is a car adapter, which converts the 12 volts provided by a car outlet into the 5 volts a cell phone needs to charge, known as a ‘step down’ converter. The main objective of the project is to design and test a bidirectional DC to DC conversion system. Most DCDC converters available on the market are unidirectional, i.e., either ‘step down’ or ‘step up’ the DC signal. Those that can switch are called bidirectional converters, but many available cannot handle the higher requirements of an electric motor. A system that can switch directions based on specific system parameters allows for situational flexibility, and the use of new devices for more efficient energy use. The supercapacitor is one such device. They provide power more efficiently than batteries but can only store a small amount of energy. They must be recharged often, which requires a step-down conversion from a power source (much like the car adapter example). Supplying the motor from supercapacitors requires a step-up conversion. So, to use, and reap the most benefit from these supercapacitors, switching from step up to step down based on their charge is a requirement. Ultimately, this would allow for the use of supercapacitors in an EV as part of a future project.

In this presentation, the process of creating a map of an area using ground truth data will be explained. The overall objective of this research project is to be able to capture a remote image of a land mass and be able to discern what sections within that image are a certain material. This is done through the matching of spectral signatures, which are unique for every physical material found on earth. A demonstration of spectral signature matching will be shown to understand the basic idea of how the mapping is done. A model expanding on this idea with the use of ground truth data will be shown with results showing how the map will be made.

Hydrodynamic Analysis of Surfboard Fin Performance set out to analyze how the outline and size of a surfboard fin can impact performance. Performance analysis involved running images from the manufacturer’s website through a MATLAB code that would process the image to determine an appropriate, numerical method, based on fluid dynamics, to explain categorical differences between fins. After testing for differences between categories for the following performance metrics: the vertical line of action, the horizontal line of action, the ratio between the tip area and the rest of the fin, and the resulting angle created by comparing the vertical and horizontal lines of action, the angle was found to be the most statistically significant factor for determining fin categories. Moving forward, users can input an image, along with the fin dimensions, to determine the performance characteristics of a fin, without having to purchase a fin. This project explains the underlying equations that are utilized, the fundamental assumptions that are made, how the results are generated, and how users can interpret the results.

Autonomous drones have been commercially available for decades. The integration of sensors has allowed robots to interact with their environment and resulting in autonomy. This quadcopter team takes on the challenge of creating an autonomous quadcopter using a frame, motors, electronic speed controllers, propellers, a Raspberry Pi, and an RPLidar. The team achieved remote control flight of the drone through pre-installed software—QGroundControl. The onboard computer will collect data using the RPLidar sensor and then send the data to the flight controller. Setting the robot (talker) and the virtual machine (listener) as nodes, they can communicate with each other through the ROS master.

Generative design implementation in this project had the goal of replacing sheet metal structures previously used to hold relays and electromechanic switches with 3D printed structures. The generative design software has the benefit of minimizing the mass of the structure, while keeping its structural integrity. The software does this by iterating through designs solving for stresses at each step, deciding where it is better to place a structure and then cutting mass at points where the structural integrity would not be compromised. Although the software creates a design on its own the user must define certain parameters: the preserve geometry (fundamental geometry for operation), obstacle geometry (sections that the software should leave without obstruction), the expected load case, manufacturing method, and material to be used. The end result is that the computer creates most efficient parts, allowing for a plastic 3D printed part to be able to safely replace one made of metal.

Humans are complex beings that take in a variety of information in a variety of different ways. Understanding that every person processes information in a different way is an important pathway in determining class structure and the method in which information is delivered to students. Students are typically multimodal learners but have a preference for certain learning methods over others. These include but are not limited to lectures, videos, reading, or having a hands-on experience. Professors have the opportunity to enhance the learning environment of their students by either tailoring their teaching method toward individual students, or by using a teaching method that acknowledges and uses each form of learning. The objective of this project is to develop a human ventilation model and corresponding video that can be used during the Case Application Session (CAS) within the Pulmonary Module at the TCU School of Medicine.

Hiller Measurements requested a mechanical design process to produce the internal chassis of their customized aerospace test equipment. The 3D printing team explored additive manufacturing to produce the generatively designed chassis using an MSLA 3D printer and photopolymer resin. The team improved production quality by standardizing support, raft, and print speed settings. Troubleshooting common 3D printing errors included reducing the effects of elephant’s foot, minimizing peeling forces, and adjusting FEP film tightness. Post-processing involved exploring the effect of cure time on material performance by utilizing dynamic vibration testing and tensile & compression testing. Final assessments were made by considering the ease of assembly of all parts and holders. 3D printing was determined to be an effective tool for production when the parts are designed for manufacturing and when the material properties are in accordance with its desired functionality. 

The reduction of CO2 emissions and the avoidance of Global Climate Change necessitate the conversion of the electricity generation industry to rely on non-carbon sources. Additionally, the mitigation of the duck-curve effects in microgrids requires the development of grid-independent buildings. Computations were performed for a cluster of one thousand grid-independent buildings in the North Texas area, where air-conditioning demand is high in the summer months. The electricity demand is balanced with energy supply generated from wind turbines, photovoltaic cells, or stored energy in hydrogen tanks. The results indicate that with one wind turbine operating, each building must be fitted with 10.2 kW rating photovoltaics capacity and a tank with 5.2 m3 of hydrogen storage capacity to satisfy the hourly demand of the buildings’ community. The addition of more wind turbines significantly reduces the needed PV rating but increases the required storage. Investing in energy conservation measures in the buildings significantly reduces both the needed storage capacity and the PV cell ratings.

The overall purpose of this project is to create a process for designing and manufacturing a Chassis (Mechanical Enclosure) for Hiller Measurements. As the Industrial Optimization sub-team, we focused on ways to optimize and fully document the process. The goal was to create procedures for utilizing 3-D generative design and printing software that most adults would be able to follow. Outside TCU students with little to no engineering background were brought in to test our procedures.

The purpose of this project is to create a closed loop system that will enable a continuous drying cycle of mined limestone through a rotating cylindrical dryer. Our client, Lhoist North America, has tasked us with designing this system, and our biggest issue has been putting together the system on a limited budget. We have determine that the most efficient method of designing the system is to used scrapped equipment that Lhoist has available and reconfiguring it for our design, rather than buying a new system. Another challenge we have faced is the method of transporting the mined limestone due to its sand-like qualities. We believe that the most effective method of designing the system will be by altering scrapped material from Lhoist’s scrapyard to complete a closed loop system of the limestone for the rotary dryer.

Dryer Testing
The parameters which were used to test the dryer was that the incline was set at 5 degrees, and the dryer rpm was at 5 and 10. Further, we used four rows of 90-degree lifters followed by four rows of radial lifters. We tested using a small grain limestone sample to be a middle of the road test. Originally, we started testing with one scoop (one quart) inside the cylinder, started the motor and turned to the 10 rpm, and added one quart every ten seconds until 4 total scoops were through the cylinder. The time this took was consistently right around the 90 second mark. However, when the volume was turned up, the findings were more interesting. When we started with a full five gallons inside of the cylinder, turned the motor up until 10 rpm, and added another five gallons at the 30 second mark, the time that it took for all of the material to exit the cylinder was right around the 90 second mark, the same time as when only a gallon of material went through the dryer.

We accumulate several cloud services on Amazon Web Services (AWS) into developing a serverless system in the cloud that replaces the current technical support request, which occurs via calls, in a classroom setting. The instructor can notify the so-called IT person with a press on the programmable Internet of Things (IoT) button. We plan to deploy the system at our university as a way for class instructors to request help without interrupting the lecture. The system is low-cost thanks to AWS's pay-as-you-go policy and easy to install.

The most viable path to alleviate the Global Climate Change is the substitution of fossil fuel power plants for the generation of electricity with renewable energy units. The substitution requires the development of very large (utility-level) energy storage capacity, with the inherent thermodynamic irreversibility of the storage-recovery process. Currently the world also experiences a significant growth in the numbers of electric vehicles, which use very large batteries. A fleet of electric vehicles is equivalent to a relatively efficient storage capacity that may be used to supplement the energy storage system of the electricity grid. Calculations based on the demand-supply data of a large electricity grid show that, even though a fleet of electric vehicles cannot provide all the needed capacity for a large electricity grid, the superior round-trip storage efficiency of batteries significantly reduces the energy dissipation associated with the storage and recovery processes. A very small amount of battery storage significantly reduces the dissipated energy in the electricity grid. Also, improvements in the round-trip efficiencies of batteries are three times more effective than improvements in hydrogen storage systems.