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Physical Construction of 1/2 Scale Concrete Wall
Get PDFThis senior project was the physical construction and material testing of the half-scale reinforced concrete wall specimens. This included all stages of the building process, from formwork and reinforcement to concrete placement and laboratory testing
Hybrid Computing for Real-time Model Predictive Control of a Buck Converter
Get PDFAdvancements in power electronics require high switching frequencies which the digital control routines of the systems cannot keep up with. Analog computing is added to digital control systems to prevent bottlenecks and allow real-time implementation. This paper proposes a hybrid computing model predictive control system for a buck converter. The control system implements the gradient dynamics of the optimization function using digital computing, and the gradient dynamics for the penalty function and integrator using analog computing. For the full simulations of the entire system, the PLECS RT Box is used to simulate the controller in real time with a 1 kHz buck converter. It also performs the digital computation when implementing the hybrid system with hardware. This project focuses on the hardware development for the analog implementation of the controller. The hardware was tested on a 1 kHz buck with hardware in the loop testing and a 50 kHz physical buck converter. The results of the testing proved that model predictive control can be successfully implemented in real time using hybrid computing. The system showed low overshoot and ripple in the output voltage of the buck converter. Future improvements remain with PWM generation and increasing the switching frequency of the buck converter
EV Microgrid Inspired Open-Source Power Inverter
Get PDFThe development of open-source power electronics platforms plays an instrumental role in accelerating microgrid deployment, electric vehicle (EV) integration, and educational access to embedded power electronic converters. This thesis presents the design, implementation, and validation of the Atinverter V2, an open-source DC to AC inverter intended for low power EV microgrid applications and educational settings. The Atinverter V2 integrates various hardware and software subsystems centered around the ATMEGA328P microcontroller, enabling PWM-based sinusoidal power inversion, DC/AC voltage and current sensing, and embedded control features. Software development leverages a C++ object-oriented library and multiple Arduino-based modules to facilitate modular and scalable operation. A dedicated GitHub repository provides full access to the schematic and layout files, firmware, simulation tools, and a Jekyll-based website with comprehensive documentation. This promotes transparency, replicability, and community driven development for the open-source community. Experimental results confirm functional PWM generation, AC waveform operation, and reliable DC/AC sensing performance. These findings establish the Atinverter as a practical and educational tool for prototyping microgrid-ready EV platforms and fostering hands-on learning in power electronics
Thermally Perfect Augmentation of a Supersonic Inlet Design Tool That Uses Method of Characteristics
Get PDFThis work is the first in a series to augment a supersonic air inlet design tool based in Python 3 to incorporate new models that increase the range of applicability of the tool. This effort focuses on improving the thermodynamics model by incorporating a thermally perfect gas model. This tool utilizes method of characteristics to solve the governing equations for an inviscid, irrotational, isentropic, steady, supersonic flow field. Multiple test cases are used to assess the accuracy of all new models. A comparison is made between the original code’s test case for a supersonic inlet at low temperatures to verify the implementation. Another test with high temperatures is presented to demonstrate the new model’s effects on the flow field. Finally, a simple geometry for hypersonic flow is created and analyzed so later work can validate the models with experimental data
Investigating the Hydration Potential of H2O Sonoma Soft Seltzer to Water and a Commercial Sports Beverage in Healthy College-Aged Women
No full textIn this randomized control trial, 60 female university students 18 to 25 years old were given to orally consume 16 fluid ounces of their treatment beverage. Twenty women were assigned to each treatment group: Water (control), commercial sports beverage, H2O Sonoma Soft Seltzer. Hydration potential of each beverage was determined by post-hydration measurements of serum potassium and serum osmolality, and hydration status measured via bioelectrical impedance. ANOVA testing was performed to investigate the differences in concentrations of post-hydration serum potassium and serum osmolality. Additionally, ANCOVA testing was performed to investigate the differences in post-hydration percent body water and amount (lbs) of body water, controlling for pre-hydration body water. When analyzing post-hydration percent body water, H2O Sonoma Soft Seltzer and the commercial sports beverage equally hydrated participants more than water (p=0.011 and p=0.029 respectively). There was a significant difference in serum potassium concentrations by group (p=0.004) where H2O Sonoma Soft Seltzer hydrated participants more than water (p=0.015) and the commercial sports beverage (p=0.007). No differences were observed in the serum potassium levels between the commercial sports beverage and water groups. There were no differences between post-hydration amount of body water nor serum osmolality between any two treatments (p=0.112 and p=0.364 respectively). This study’s results showed that H2O Sonoma Soft Seltzer exhibited higher hydration potential than commercial sports beverage and water
Quantifying Harmful Trunk Postures: Inertial Sensor Analysis of Trunk Angle to Support Low Back Pain Prevention
Get PDFLow back pain is a highly prevalent condition worldwide, impacting up to 80% of individuals at least once in their lifetime. A critical gap in current prevention strategies is the lack of tools to accurately measure trunk posture and movement in real-world environments. Accurate identification of biomechanical risk requires information about movement intensity, duration, and frequency, yet traditional assessment methods rely on self-reporting or visual observation, which are time-consuming and prone to error. To address this gap, a wearable monitoring method, consisting of two Inertial Measurement Units, was designed to quantify risk exposure to the spine by measuring angular position of the trunk over time. This method was validated against an optoelectronic motion capture system during controlled single and multi plane movement protocols. High agreement was observed between the wearable system and motion capture for sagittal plane angles, with greater variability in coronal and transverse planes during multi-plane movement trials. These findings support the feasibility of using wearable IMUs to monitor trunk posture in field settings, particularly for capturing flexion-related low back pain risk
Adaptive Riding Mount Block
Get PDFProfessor Sarah Stewart from the Animal Science Department at Cal Poly seeks to develop a solution to help people with disabilities mount horses. Users need a mounting block that can bring them closer to the horse’s back to ease mounting. The current system, consisting of two plastic two-step blocks, is inadequate—unstable, too small, and inaccessible for wheelchair users.
The required solution must meet several key specifications: it should accommodate at least three people standing side by side, be sturdy enough to support their combined weight, and remain stable on rugged terrain like gravel or sand without tilting or sinking. Additionally, it needs to be portable, collapsible, and lightweight enough to be carried by two people.
Our primary stakeholders are our sponsor, Professor Sarah Stewart, and the users of the Oppenheimer Equine Center. Our team, Team RMB (Riding Mount Block), is responsible for designing and manufacturing a new mounting block to help mentally disabled people from Professor Stewart’s program mount horses. She also requests that in the future this system can be easily modified to cater to people with physical disabilities. The existing solutions on the market are too big and bulky, cost too much, and don’t have the height variability our sponsor requests.
This report provides a broad overview of our design project and demonstrates to our sponsor our understanding of the problem with a clear definition. To align our understanding with our sponsor, we’ve incorporated background research and a detailed project plan, via a Gantt Chart [Appendix C] with established milestones and task assignments. Additionally, this Scope of Work (SOW) serves as the initial step in our formal project documentation, and we invite our sponsor’s input on any concerns as we move into the ideation phase.
This report is structured to provide clear and thorough coverage of our engineering project. A key section is the Customer Needs table, which aligns engineering specifications with customer requirements using the Quality Function Deployment (QFD), process [Appendix A]. This table not only ensures traceability but also evaluates the feasibility of the engineering specifications. Another important section is the Engineering Specifications table. It lists each specification along with the planned verification methods and highlights the challenges involved in meeting target values and tolerances
Catalyzed Chemical Recycling of Poly(Ethylene Terephthalate) For Enhanced Sustainability
No full textPlastics are ubiquitous in the production of consumer and industrial products; their chemical stability, low cost of production, and performance versatility make them the best option for many industries. Their inherent benefits, specifically durability, is the basis for the negative environmental impact of polymers. Improper containment of endof-life polymer products causes unintentional migration into the environment. The monomers for many common polymer types are also fossil fuel based further increasing the environmental impact of the plastic lifecycle. Recycling is a possible method of closing the loop of the plastic lifecycle. Currently most recycling is physical, thermally reprocessing used plastics into products of much lower quality. Chemical recycling fully depolymerizes used plastics into monomers that can be readily used to create new products without quality loss. Poly(ethylene terephthalate) is a polyester that accounts for approximately 10% of the global plastic supply and is a great candidate for chemical recycling as it susceptible to many types of degradation. Many chemical recycling methods use non-sustainable chemical reactions and catalysts that are successful in degrading the used plastics but fail to reach environmental impact goals necessary to be considered a green process. Glycolysis is a well-studied method of PET recycling that has low environmental impact but is too slow to be widely implemented. This reaction v produces bis(hydroxyethyl) terephthalate (BHET) that can be used to easily produce various polymer products. Ionic liquid (IL) based catalysts can be used to accelerate glycolysis considerably. In addition, they are considered green catalysts since they can be reused multiple times without losing catalytic ability. This study is focused on optimizing the chemical recycling of PET via glycolysis catalyzed by [BMIM]ZnCl. In addition, the impact of polymer morphology on chemical recycling will be evaluated by comparing the product yield and kinetics of degraded crystalline and amorphous PET. Plastic materials and degradation product testing included structural characterization, thermal property analysis, reaction kinetics calculations, and yield/material usage optimizations. Optimal conditions for \u3e90% yield of BHET were found for both polymer morphologies. It was also observed that amorphous polymers are more susceptible to chemical recycling requiring a shorter time to degrade
Multimodal Self-Folding of Shape Memory Polymer Using Laser Induced Graphene
Get PDFShape memory polymers (SMPs) can undergo programmed shape transformations when heated above their glass transition temperature (Tg), enabling actuation through stimuli such as infrared (IR) radiation and Joule heating. These materials are promising for deployable systems and soft robotics due to their lightweight structure and elimination of traditional mechanical components. While IR-based actuation is simple and low-cost, it lacks precision in uncontrolled environments. Joule heating offers improved control but is often limited by conductive ink properties such as thickness, stiffness, or poor adhesion. This work introduces a novel method for multimodal SMP actuation using laser-induced graphene (LIG) transferred from polyimide to polystyrene (PS)-based substrates. The resulting conductive patterns enable both IR absorption and resistive heating, providing a reliable and scalable approach to SMP activation. An experimental study was performed to investigate the self-folding performance of the SMP sample using LIG patterns under IR and Joule Heating. The heat transfer process through the SMP substrate was also studied for IR heating using numerical analysis in MATLAB to support experimental findings
Great Big Beautiful Tomorrow : Disneyland, Science, and the Cultural Cold War
Get PDFDisneyland, the popular Anaheim-based theme park in California, opened its doors during heightened Cold War tensions in 1955. In this thesis, I trace the origins of Tomorrowland, one of the five original themed lands in Disneyland that included futuristic rides and attractions to depict Walt Disney’s imagining of the year 1986. I examine Tomorrowland in particular to argue that WED Enterprises (Disneyland, Inc.’s research and development arm) and Disney’s vision of scientific progress aligned with U.S. Cold War policy goals, especially containment. Disney and WED Enterprises meticulously planned Tomorrowland with the help of notable American defense contractors, including the Monsanto Chemical Company. In addition, Tomorrowland exhibited how technological developments could create suburban affluence and abundance, which was a key aspect of U.S. cultural diplomacy. As the Eisenhower Administration realized the significance of Disneyland’s popular messaging, the U.S. Department of State strategically ushered foreign diplomats, especially the architects of the Non-Aligned Movement, to the theme park to win over their “hearts and minds.” In showcasing how capitalism and scientific freedom could bring about progress and prosperity to audiences at home and abroad, the Disneyland theme park was a crucial, but often overlooked, vehicle for Cold War cultural mobilization and policy