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Development and Testing of a Lab-Scale Resonance Igniter for Rocket Propulsion Applications
Get PDFThe resonance igniter is a type of rocket engine ignition system that initiates spontaneous combustion without using an external ignition source. This is possible because the activation energy needed for the combustion reaction to take place is provided by the igniter as it receives propellant flow. This can simplify the igniter hardware and lends it high re-usability while enabling the use of high-efficiency propellant combinations. Its potential benefits could make it a desirable alternative to traditional approaches such as using spark igniters or hypergolic propellants. The present research strove to inaugurate the study of the resonance igniter at Cal Poly by designing, building, and testing a lab-scale prototype of the technology and attempting to achieve resonance ignition with a methane-air mixture. Within the igniter, gaseous flow travels into a sonic nozzle, creating an underexpanded jet which exits into a resonance tube closed at one end; this device is called a Hartmann-Sprenger Tube (HST). This produces a flow oscillation phenomenon that generates heat and raises the gas temperature, enabling combustion of a flammable mixture if the mixture’s autoignition temperature is reached. Ensuring choked flow in the chamber exit orifice downstream of the HST successfully stabilized the pressures within the igniter and enabled higher temperatures to be reached with increasing inlet pressure. The Hartmann-Sprenger Tube produced measured temperatures above 500°C and reached peak performance when the key test parameters NPR and S/d ratio were ∼6.2 and 2.68 respectively. Flow oscillations while at this optimal condition appeared to correspond to the Jet Regurgitant Mode, while the Jet Screech Mode produced comparatively lower temperature rise. Ultimately, the igniter was unable to produce unambiguous combustion through resonance ignition, primarily because the achieved temperatures likely failed to reach the autoignition temperature of the methane-air mixture
7LR-C Upper Limb Dancing Prosthetic
Get PDFElla Wallis, a student at Cal Poly and performer in the Cal Poly Drag Club with a trans humeral upper limb difference, wants a prosthetic device that allows for a large range of motion and high degree of articulation to help them better dance in the style of voguing, allowing them to express themselves further while performing. The prosthetic arm is body-driven and relies on momentum to reposition. It attaches to the user through a harness, which is clipped to a socket with elastic straps to not impede the shoulder’s range of motion. The design contains urethane resin, aluminum, stainless steel, and fiberglass structural components, as well as silicone aesthetic features. The specifications of three distinct degrees of motion, comfortability, secure attachment, and aesthetic design have been met to an adequate degree
Conversational Social Robot
Get PDFBackground: Social robots are used in various settings to reduce burden on human workers and expand opportunities for people in need of assistance.
Challenge: Design a humanoid robot head and torso capable of holding conversations and interacting with a user using a LLM and motion. Conversations are limited to discussing Cal Poly resources and opportunities with visitors to the Bently Research Center on campus
Van Accessibility
Get PDFThe SLO Achievement House provides resources and activities for their clients, including daily trips to different parts of the community, to keep their clients connected to society. These trips require the clients, many of whom struggle with general mobility and strength, to step up to the high entrance of a van or company car. This daily activity poses a challenge both physically and emotionally for the clients. The current solution utilizes commercially available step stools, which lack handrails, overall stability, and adequate step depth. The Achievement House needs a stool or ramp tailored to their client’s needs and their specific vehicles
Aerospace Fastener Installation Tool
Get PDFContamination, particularly in aerospace manufacturing environments, is a significant concern, especially with fastener designs that incorporate torque-rated breakaway pieces for easier installation. These breakaway pieces are also known as pintails. Howmet has tooling that can collect loose pintails during installation, but they have small capacities and are not ergonomic for aerospace technicians. Their current need is for a light and ergonomic tool capable of installing a wide variety of Ergo-Tech® fasteners while having a large capacity to collect pintails and improve aerospace manufacturing methods. For this Critical Design Stage, we have finalized a design that allows Pintails to pass through the center of the tool and be collected remotely for large capacity
Micro Mobile Home R3
Get PDFHomelessness is an ever-growing issue all around the world. In 2023, over 250,000 or ~40% of all people experiencing homelessness did not have access to shelter spaces in the U.S. [1]. All people have the right to a place where they are safe from violence, crime, and the constant fear that they will be forced out.
Both homeless people and outdoor enthusiasts need a new way to keep themselves and their belongings safe when living outdoors, since existing products do not offer adequate security, portability, or versatility
Test Equipment Automation and Remote Operation Curriculum Senior Project
Get PDFThe goal of this project is to create new lab procedures and lab bench permutations for Cal Poly EE students to implement automated Test and Measurement equipment into their electrical engineering education. Currently EE students at Cal Poly have no classroom based opportunities to learn about leveraging software skills and test equipment knowledge in order to automate measurements, which is a valuable skill for an electrical engineer in the workforce. The curriculum outlined in this project will include three experiments, each leveraging an instrument controller, and Python as the primary scripting language. Each procedure will require students to write Python code that runs on an instrument controller, and leverages different pieces of test equipment, or sensors, that are connected over a local area network (LAN) in order to perform automated measurements and actions. These include, measuring the output characteristic curve of a Bi-polar Junction Transistor (BJT) transistor across multiple base currents via a multimeter and DC power supply, creating IV curves of linear and non-linear devices, and building wide-band transmission coefficient plot generators
An Analysis of the Power Consumption of Various Computer Vision Machine Learning Techniques on a Microcontroller Utilizing the ClusterDuck Protocol
Get PDFConstant data processing is essential for effective data collection, particularly in remote and hard-to-reach areas. The need for efficient, autonomous data acquisition and transmission is increasingly addressed by integrating machine learning within larger communication networks. This paper explores the application of machine learning techniques with Internet of Things (IoT) mesh networks. Utilizing the LoRa communication protocol, data is captured and analyzed on an edge device and transmitted to a larger communication network. The ClusterDuck Protocol (CDP), developed by OWL Integrations, serves as an IoT mesh network designed to allow for communication in areas lacking traditional static infrastructure such as WiFi or power lines. This project investigates the implementation of supervised machine learning algorithms including support vector machines (SVM), logistic regression, and convolutional neural networks (CNN) to enhance remote data processing capabilities and transmit results within the CDP network at low power. To study this, this project utilizes computer vision machine learning techniques to identify the presence of animals in proximity. The findings of this research highlight the potential for machine learning to enhance LoRa-enabled IoT networks. This paper analyzes multiple techniques to determine trade-offs between accuracy and power consumption, providing groundwork for designing robust IoT networks capable of supporting autonomous, low-maintenance environmental monitoring systems in resource-constrained, remote areas
Environmentally Friendly Removal of Positive and Negative Photoresist from Silicon Wafers with and Without a Silicon Dioxide Film
No full texthe process of photolithography is critical to the creation of semiconductor devices such as computer chips and solar cells. Precise placement of dopant atoms and metal lines within a semiconducting material is required to produce these devices. The patterning of photoresist that is created by exposure to UV light during photolithography serves as a mask that allows dopant atoms and metal lines to be placed in specific regions of the semiconductor substrate. When properly located, the metal lines and doped regions of the semiconductor combine to form devices such as p-n junctions. The p-n junctions serve as building blocks for integrated circuits used daily by billions of people worldwide
The Effect of Whole Fruits High in Anthocyanins on Markers of Glycemic Control in Women
Get PDFCardiometabolic diseases are a significant health burden worldwide and remain the leading cause of death among adults in the United States. Type 2 diabetes mellitus (T2DM) is a central component of cardiometabolic dysfunction and substantially increases the risk for cardiovascular disease. As women enter the post-menopausal period, significant declines in estrogen levels lead to a heightened risk of T2DM in this population. Observational and experimental evidence has shown potential for fruits high in anthocyanins (ACs) to reduce the risk of T2DM and improve glycemic control. This systematic review and meta-analysis examined the current research on whole fruits high in ACs on glycemic control in women. This meta-analysis included 12 studies and followed the guidelines set by PRISMA 2020. The analysis showed no significant effect of AC-rich fruit consumption on biomarkers of glycemic control, including fasting blood glucose, glycated hemoglobin, fasting insulin, and the homeostatic model assessment of insulin resistance. Further research is needed using larger, female-specific samples and standardized interventions to determine the clinical utility of anthocyanins in cardiometabolic risk reduction