Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Engineering

Performance-Based Risk Assessment For Large-Scale Transportation Networks, Anteneh Deriba, David Y. Yang May 2024

Performance-Based Risk Assessment For Large-Scale Transportation Networks, Anteneh Deriba, David Y. Yang

Student Research Symposium

Efficiently assessing the risk of asset failure due to deterioration or extreme events is crucial for transportation asset management. Traditional methods often lack effectiveness in directly evaluating system performance-based risks, facing challenges like the exponential increase in system states and the emergence of low-probability high-consequence events ("grey swan" events). To address these, this paper introduces a novel performance-based risk assessment approach for large-scale transportation networks, inspired by the Transitional Markov Chain Monte Carlo (TMCMC) method. This method transforms the risk assessment problem into a high-dimensional posterior distribution, with system risk acting as the normalization factor (evidence). It also provides risk-based …


Comparative Life Cycle Assessment Of Hydrogen Production Via Various Pv-Assisted Electrochemical Water Splitting Techniques, Achyuth Ravilla May 2024

Comparative Life Cycle Assessment Of Hydrogen Production Via Various Pv-Assisted Electrochemical Water Splitting Techniques, Achyuth Ravilla

Student Research Symposium

Photoelectrochemical (PEC) and photovoltaic-electrochemical (PV-EC) water-splitting technologies have emerged as cost-effective options for large-scale green hydrogen production in industrial applications. Solar to hydrogen (STH) efficiencies of these technologies have reached up to 20% and several pathways have been explored to drive down the cost of hydrogen using these technologies to less than $2/kg. However, the environmental impact assessment of these technologies for industry-scale deployment has not been explored in previous studies. This study assesses the environmental impacts of PEC and PV-EC technologies by conducting a cradle-to-gate life cycle assessment. The functional unit considered for this assessment is 1 kg of …


Flexible Strain Gauge Sensors As Real-Time Stretch Receptors For Use In Biomimetic Bpa Muscle Applications, Rochelle Jubert May 2024

Flexible Strain Gauge Sensors As Real-Time Stretch Receptors For Use In Biomimetic Bpa Muscle Applications, Rochelle Jubert

Student Research Symposium

This work presents a novel approach to real-time length sensing for biomimetic Braided Pneumatic Actuators (BPAs) as artificial muscles in soft robotics applications. The use of artificial muscles enables the development of more interesting robotic designs that no longer depend on single rotation joints controlled by motors. Developing robots with these capabilities, however, produces more complexities in control and sensing. Joint encoders, the mainstay of robotic feedback, can no longer be used, so new methods of sensing are needed to get feedback on muscle behavior to implement intelligent controls. To address this need, flexible strain gauge sensors from Portland company, …


Characterization Of Chopped Carbon Fiber Reinforced Composites Produced Using Fused Deposition Modeling, Jonathon Tran, Rachel Shubella May 2024

Characterization Of Chopped Carbon Fiber Reinforced Composites Produced Using Fused Deposition Modeling, Jonathon Tran, Rachel Shubella

Student Research Symposium

Fused deposition modeling (FDM) is an additive manufacturing (AM) process which can create parts with complex geometries in their final shape without need for additional specialized tools or devices. The FDM process builds parts by adding material layer by layer only where it is needed, saving energy, costs, production time for complex parts, and minimizing waste. Fiber reinforcement can significantly enhance the mechanical properties of a polymer material and depends significantly on the fiber length distribution and fiber orientation distribution of the final part. In this research, we investigated the various infill patterns of FDM printed Markforged onyx which is …


Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein May 2024

Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein

Student Research Symposium

Advancements in robotics and bioengineering aim to emulate biological muscle systems through robotic actuators, blending mechanical strength with biological adaptability. A lesser-explored aspect is mimicking the pulse-like control characteristic of biological muscles, which contract in response to action potentials from motoneurons, with muscle contractile force relying heavily on the timing between these potentials. This study explores the effect of pulse lengths and the gaps between pulses on braided pneumatic actuators (BPAs), which mimic the nonlinearity and dynamic response of biological muscles. It hypothesizes that artificial muscles utilizing pulse-based control will exhibit a similar force dependency on the intervals between pulses …


Self-Balancing Robot Leg, Ben Bolen May 2024

Self-Balancing Robot Leg, Ben Bolen

Student Research Symposium

Research in the Agile and Adaptive Robotics Lab involves the creation of biomimetic robots. To this end, we developed a self-balancing robot leg actuated with braided pneumatic actuators (BPAs)—a type of pneumatic artificial muscle. These BPAs, akin to human muscles, exhibit properties such as high strength-to-weight ratio and tunable passive stiffness. An Inertial Measurement Unit (IMU) was placed on top of the tibia for feedback and the tibia and foot were connected with a hinge joint. The orientation of the ankle joint was controlled with an Arduino microcontroller sending commands to the proportional pressure valves supplying the BPAs. Leg balance …


Reducing Switching Noise And Losses In Two-Stage Electric Power Converters, Abhijeet Prem May 2024

Reducing Switching Noise And Losses In Two-Stage Electric Power Converters, Abhijeet Prem

Student Research Symposium

Advancements in semiconductor devices are enabling the design of better electrical power converter systems. Wide Bandgap (WBG) switching devices from Silicon Carbide and Gallium Nitride can operate at high temperatures, voltages, and frequencies with faster turn-on/off periods, improving converter performance over silicon devices. However, WBG technology is still new, and the rapid switching transitions of these devices lead to issues such as voltage overshoots, ringing, and electromagnetic interference, which need to be addressed for widespread adoption. This work introduces a new control method for reshaping the switching voltages, which overcomes the disadvantages of fast transition time without increasing the system's …


Plasma Ion Source, Nathan K. Davis May 2024

Plasma Ion Source, Nathan K. Davis

Student Research Symposium

It is well known that a plasma can be created with both high input power and ultra low pressure. The challenge is in creating these same plasma characteristics with both lower power while maintaining a higher pressure. We have developed an ion beam by careful manipulation of magnetic and electric fields. Magnetic fields are used to accelerate ambient electrons to ionize the low pressure gas into a plasma. Electric fields are used to extract the ions into a focused beam. To achieve these initial ionizations, an artificial vacuum is created to reach low enough pressures to ionize the gas. A …


Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik May 2024

Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik

Student Research Symposium

Perovskite solar cells (PSCs) have emerged as a promising option for solar energy generation. However, it is essential to consider the environmental impact of these innovative photovoltaic (PV) technologies as the industry moves towards commercialization. Researchers are currently exploring ways to recycle PSCs to recover valuable materials and reduce their environmental impact at the end of their life. To ensure the sustainability of PSCs, this study evaluates and compares the environmental impacts of five recently developed recycling approaches. The Tool for Reduction and Assessment of Chemicals (TRACI) method was utilized to measure environmental impacts in categories such as acidification (kg …


Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt May 2024

Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt

Student Research Symposium

As neural networks have become prolific solutions to modern problems, there has been a congruent rise in the popularity of the numerical machine learning techniques used to design them. While they are highly generalizable, numerical methods tend to produce networks that act as inscrutable “black boxes,” making it difficult to interpret their behavior. One solution to the problem of network transparency is to use analytical techniques, but these methods are underdeveloped compared to their numerical alternatives. In order to enhance the viability of analytical techniques, this work extends previous efforts to quantify the impact that non-spiking neural encoding schemes have …