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Autonomous Mapping Rover
Get PDFThis report details the design, implementation, and evaluation of Rovero, an autonomous mapping rover developed as a senior project. Rovero integrates state-of-the-art technologies, including ROS2 for communication, SLAM algorithms for mapping, and sensor fusion for accurate navigation. The project aimed to achieve robust autonomous operation in indoor environments, leveraging a combination of LiDAR, IMU, and encoder data for real-time decision-making. Key challenges addressed include path planning, obstacle avoidance, and integration of multiple sensor inputs. Results demonstrate successful mapping capabilities and efficient navigation performance
The Gauge/Gravity Holographic Duality Between String Theory and Quantum Field Theory: A Full Introduction
Get PDFThe Anti-deSitter Spacetime / Conformal Field Theory (AdS/CFT) correspondence is a well known holographic duality between ten dimensional superstring theories and conformal quantum field theories. The existence of such a correspondence is fascinating and the duality provides a powerful tool-set for working out problems in both string theory and quantum field theory. The correspondence defines a dictionary of terms that exist dual to one another in each theory, allowing theorists to understand the dynamics in one system based on quantities from another. Furthermore, when one side of the duality has strong coupling (meaning the approximations of perturbation theory are no longer valid), the other theory will have weak coupling, making this a powerful tool for computations in a strongly coupled theory. The AdS/CFT correspondence ties together multiple advanced areas of physics, including general relativity, quantum field theory, and string theory, requiring a large amount of knowledge for any scientists aiming to use the dictionary. This document is a compendium of theoretical physics from all these different areas, culminating in a discussion of the AdS/CFT correspondence that brings them all together. Prior knowledge of quantum mechanics and basic general relativity is assumed
Wireless Communication in Autonomous Vehicles
Get PDFThis project focuses on building a realistic, standards based V2X communication platform using DSRC (IEEE 802.11p) to support future autonomous vehicle control research. The system is built around commercial off-the-shelf (COTS) hardware, specifically the NXP i.MX 8XLite – V2X Evaluation Kit, which integrates an automotive-grade processor and the SAF5400 V2X modem to handle low-level DSRC transmission in the 5.9 GHz band.
We successfully completed the hardware bring-up, verified over-the-air communication between two nodes, and performed initial RF characterization using a spectrum analyzer. The SAF5400 was confirmed to operate on all seven DSRC channels (172–184), maintaining the correct 10 MHz bandwidth centered on each frequency in compliance with the IEEE 802.11p standard. We also measured the system’s power draw under idle and transmit conditions to support future power budgeting and integration with mobile platforms such as TurtleBots.
A key objective of the project was to enable the transmission of fully custom, user-defined data over the V2X link. We successfully used the llc tx command to transmit fully custom 802.11p frames and verify their reception on another node using llc rx. This confirmed that reliable transmission of arbitrary payloads is possible using the existing software stack. All payloads were received as expected, with the exception of a 4-byte region that is automatically modified, likely for internal data for sequencing the number of transmissions. This capability provides a solid base for future teams to transmit real-time vehicle data to other vehicles using this V2X system.
The next steps include automating this transmission process, integrating live data sources such as messages from the exposed CAN bus, and physically integrating the V2X kits onto the TurtleBots with dedicated electrical power subsystems (EPS). These additions will enable the V2X kits to support an autonomous vehicle wireless communication system between TurtleBots that are compliant with industry standards today
Impacts of Temperature Acclimation on Swimming Performance and Metabolic Dynamics of the Amargosa River Pupfish, Cyprinodon nevadensis amargosae
Get PDFClimate change is leading to warmer atmospheric temperatures in many regions of the world, which in turn is raising the temperatures of aquatic habitats and simultaneously shifting the frequency and severity of extreme precipitation events. In fishes, metabolic demands are higher under warmer conditions, while dissolved oxygen levels typically decline in warmer water. This mismatch may limit the ability of fishes to cope with high water flow events like floods that can occur following extreme rainfall. A few species of pupfishes (genus Cyprinodon) in the Death Valley region of California and Nevada, USA, occupy stream or river habitats with high temperatures in summer. These pupfish populations are largely considered resilient to flash floods. However, if climate change results in extreme rainfall events becoming more severe and frequent during the warmer months of summer and early fall - when pupfish may also be experiencing even warmer temperatures from climate change - such high-flow events may have detrimental consequences on pupfish survivorship. A full recognition of what those potential effects might be requires understanding how elevated temperatures alter pupfish swimming performance and metabolic physiology. Here, we investigated how temperature affected the metabolic and swimming performance of adult Amargosa River Pupfish, Cyprinodon nevadensis amargosae. This species is endemic to the Amargosa River in the Death Valley region. Temperatures in this small river system can exceed 40˚C during summer. The river also frequently experiences flash flooding during rain events. Adult Amargosa River Pupfish were acclimated to temperatures of 16˚C, 27.5˚C, or 35˚C for a duration of 63 to 114 days, and then tested for differences in Critical Swimming Speed (Ucrit) and several measures of metabolic performance (standard metabolic rate, SMR; maximal metabolic rate, MMR; aerobic scope; critical swimming speed, Ucrit; and Cost of Transport at Ucrit, COT) using an intermittent swim-tunnel respirometer system. Following these swim trials, skeletal muscle tissue was collected from each fish. Muscle tissue was sectioned and stained for succinic dehydrogenase (SDH) to determine subsarcolemmal mitochondrial density, as well as muscle fiber morphological characteristics. Enzymatic assays were also conducted to determine lactate dehydrogenase (LDH), citrate synthase (CS), and pyruvate decarboxylase (PDC) activity levels in skeletal muscle. Critical swimming speed (Ucrit) increased in pupfish from 16˚C to 27.5˚C, but then declined at 35˚C. That decline in swimming performance was paralleled by a reduction in aerobic scope and increase in the metabolic cost of transport at 35˚C, implying that pupfish were unable to meet additional energetic demands aerobically at that 35˚C temperature. Those changes in aerobic metabolic capacity were associated with a lower oxidative capacity in both red (‘slow twitch’) and white (‘fast twitch’) skeletal muscle as indicated by mitochondrial density via SDH staining intensity, as well as reduced muscle citrate synthase activity in pupfish at 35˚C. Taken as a whole, these findings point to reduced aerobic swimming capacity in adult Amargosa River pupfish experiencing a prolonged period of high temperatures. That reduced aerobic swimming performance is likely to compromise the ability of pupfish to endure, and survive, high-flow regimes that occur during periods of high temperatures
Teaching #MeToo and #BlackLivesMatter Amid the Anti-Woke Moral Panic
Get PDFThe introduction of over 100 anti-DEI bills across 30 states and President Trump’s signing of executive orders that target DEI programs demonstrate the backlash against the social, cultural, and political gains made by movements such as #MeToo and #BlackLivesMatter. “Anti-woke sentiment presents challenges for educators preparing students to engage critically with certain histories, movements, and theories. This article explains current debates around what it means to be “woke”; provides strategies to teach about inequality across race, gender, class, and sexuality in this polarized environment; and imagines futures that uphold the ideals of diversity, equity, and inclusion
Novel Electrospinning Techniques for Fabricating Scaffolds to Model Intracranial Atherosclerotic Disease in Tissue Engineered Blood Vessel Mimics
Get PDFNovel Electrospinning Techniques for Fabricating Scaffolds to Model Intracranial
Atherosclerotic Disease in Tissue Engineered Blood Vessel Mimics
Isaac “Squeaky” Buentipo
Dr. Kristen Cardinal’s Tissue Engineering Lab at California Polytechnic State University specializes in fabricating customized vascular models, known as Blood Vessel Mimics (BVMs), for medical device testing. BVMs are simplified in vitro vascular models designed to bridge the gap between bench testing and in vivo evaluation of intravascular medical devices. BVMs are produced by combining a polymer scaffold with human vascular cells. Through novel scaffold fabrication techniques, such as silicone injection molding, silicone dip casting and electrospinning, the capabilities of the BVM model have evolved to model tortuous vessels and vascular pathologies, including aneurysms. However, the current modeling capabilities do not extend to luminally occluded vascular pathologies, such as intracranial atherosclerotic disease (ICAD). Therefore, the goal of this thesis was to develop and fabricate an electrospun fibrous polymer scaffold with luminal occlusion, suitable for translation into a blood vessel mimic.
The first aim of this thesis was to investigate the feasibility of the methods used for fabricating and characterizing fibrous polymer scaffolds with internal geometries, using a modified collection mandrel. Electrospinning parameters for optimal internal geometry generation on the modified mandrel were identified and implemented. Although scaffolds were successfully fabricated, the occlusion levels were insufficient to be clinically relevant. This limitation led to the second aim, which focused on investigating novel electrospinning approaches to create fibrous polymer scaffolds with clinically relevant lesions. By exploring mandrel additions and mandrel alterations, the newly fabricated barbell mandrel emerged as the optimal method for fabricating customizable occluded scaffolds. Using this technique, scaffolds were generated with 50% and 70% luminal occlusion and lesion lengths ranging from 0.5 cm to 3 cm. The third aim of this thesis evaluated the preliminary efficacy of the generated occluded scaffolds as BVMs through an acute vessel cultivation study, assessing cell deposition across the scaffold lumen. The results showed consistent cell deposition across the generated vessels. Further work is needed to generate occluded vessels over longer cultivation periods to fully evaluate their utility as disease models for medical device testing. In summary, this thesis developed and implemented methods for electrospinning luminally occluded fibrous polymer scaffolds and demonstrated their preliminary application in creating BVMs, laying the groundwork for future advancement of occluded vessel modeling within Kristen Cardinal’s Tissue Engineering Lab