This thesis presents novel feedback and feedforward control system design strategies for active to passive vibration mitigation of residual vibrations on high speed machine tools. Residual vibrations on high-speed machine tools are triggered when the machine axes (table) undergo large accelerations, which induce sudden inertial forces and excite the lightly...
Laser Powder Bed Fusion (LPBF) is a process commonly used to create additively manufactured metal parts. The flexibility and complexity allowed by the LPBF process provides opportunity for significant advancement in multiple industries as parts can be customized in shape and function for specific needs. These benefits can be compounded...
The surgical standard of care to partially restore grasping function after a traumatic spinal cord injury is a reconstructive tendon transfer-surgery that connects all four finger flexors to an expendable wrist extensor. While restorative, this surgery has a fundamental problem; the movement of all four fingers flexors is directly coupled,...
The severity of wildfires around the globe is increasing. At the same time, urban development is expanding outward into areas where severe fires occur. There is an increased risk of home loss to fires in areas where severe fires and urban expansion meet. Ignition of homes or nearby fuel is...
Wildland fire refers to an unpredictable and uncontrollable fire that happens in wildland areas. Regardless of the beneficial impacts of wildland fires on ecosystems, the destructive impacts of wildfires on air quality, economy, public health, etc. are considerable. An essential goal in the fire community is that the wildland fires...
In the United States, the oil and gas extraction industry produces large amounts of highly contaminated wastewater that is seldom treated for reuse in other applications. Current wastewater storage and disposal strategies lead to contamination of valuable freshwater resources that can have negative effects on both human communities and the...
Thermal wave imaging (TWI), a technology based on heat conduction and radiation through materials, is a relatively new addition to current non-destructive inspections (NDI) systems. Bonding of composites, an extremely important step in manufacturing and repair of laminates, could be affected by defects originating from faulty manufacturing processes or damages...
This thesis describes an automated method to estimate tree trunk width in a commer-cial apple orchard. Trunk cross sectional area, which is an important consideration with regards to nutrient uptake, is a feature being integrated in a decision support system for precision Nitrogen management. The data used to generate the...
0.1 Purpose of Report
During my time on this project, I have written two reports. My SAE22 ePowertrain report details last year's design, the design process, design changes, and manufacturing in extreme detail. The capstone course report will be useful for future students looking to educate themselves on everything that...
This thesis explores the differences in puppetted and teleoperation control of robotic hands, using the Asterisk test as a benchmark. Two hands were tested, including modified versions of the Model Q and Model Q developed by Yale's GRAB Lab. Small differences were observed between the puppetted and teleoperation control of...
In engineering problems not all constraints can be explicitly written as mathematical functions. There needs to be a way integrate designer knowledge into the design process and preferably use that to guide an optimization problem. In this thesis, these constraints are modelled using classification surrogate models and integrated with Bayesian...
Fiber reinforced polymers have gained considerable attention due to their wide range of applications, leading to significative concerns for end-of-life recyclability and disposal. Natural fibers and recycled carbon fibers, coupled with thermoplastic matrices can provide a sustainable and environmentally friendly alternative to traditional materials.
This study focused on experimental materials...
The accelerated development in water-energy systems calls for advanced modeling and optimization tools to improve technologies’ performance. Water desalination is a manifestation of water-energy system that is challenged by different operational constraints. The scarcity and uneven distribution of freshwater around the world makes water desalination an indispensable process to address...
The development of a continuous and reliable cooling method for computer chips is an evolving subject requiring continuous research in both computer science and thermal management. Two-color laser induced fluorescence (LIF) provides a non-invasive way to investigate electronics cooling fluid behavior. Dielectric fluids are of particular interest as they allow...
Aluminum alloys are popular in aerospace and automotive industries because of their relatively high strength-to-weight ratio. The study of enhancing aluminum’s mechanical properties through grain refinement is especially important. One such technique is High-Pressure Torsion processing (HPT), which leads to significant grain size refinement and enhances mechanical properties like ductility...
The application of a flapping foil with prescribed trailing edge motion to energy harvesting in a low reduced frequency (k = fc/U∞) regime was experimentally studied. The effects of the phase and amplitude of the applied trailing edge motion upon time-variant power extraction capability have been measured and are interpreted....
Modeling of hydraulic fracturing wastewater treatment systems must be very accurate so it can be used for real-time modeling and control of the process. The treatment of hydraulic fracturing wastewater is complex because of the variability of the composition of hydraulic fracturing wastewater. In this work, literature review of hydraulic...
The US industrial sector accounts for about one-third of the nation’s energy consumption and is predicted to grow twice as quickly as other sectors through 2050. International organizations such as the International Energy Agency project energy efficiency improvements will account for over 40% of greenhouse gas emissions reductions through 2040....
Creating effective packaging is about finding a balance between product protection during shipping and time consumption in the design process. Given time and cost constraints, it is hard to produce sufficiently protective padding while having it not be thicker than it needs to be. This thesis describes a method to...
Water supplies are diminishing worldwide and by 2025 two thirds of the population could be living in regions of water scarcity (local demand for water is greater than water supply). One method to increase available water sources is to use desalination technologies to separate water from saline solutions. While desalination...
Desalination stands for removing salt from saline water, and produce freshwater. Desalination technologies have been envisioned as a potential solution for freshwater production from oceans as an immense source of water acquiring 97% earth’s water, and 75% of earth’s surface. However, one third of world’s population face water scarcity every...
Manufacturing technology has continuously evolved and advanced over the past century; this has led to an increase in the production of consumer and industrial goods driven by simultaneous growth in population and wealth. Despite the resulting economic and labor growth, environmental impacts of manufacturing have increased dramatically due to the...
The grid geometry plays a vital role in the performance of gridded ion thrusters. It can dramatically impact the erosion rate and thrust. Designers push the limits of electric in-space propulsion by optimizing grid parameters through simulation. At the same time, computational models of plasma physics are intensive. A baseline...
Countries have begun to adopt green energy initiatives requiring high percentages of power generation to come from clean energy sources. Both onshore and offshore wind energy generates reliable clean energy. Due to this, wind energy has had an exponential growth in global adoption. While wind energy is increasingly adopted by...
This work details the development of 3D printed TPU pneunet actuators for use in apple picking for agricultural soft robotics. These actuators increase the force capabilities of soft pneunets and simplify manufacturing. Grippers based on these actuators are ideal for apple picking because they are compliant, yet exert sufficient force...
In current prosthetic practices, the design process heavily relies on the prosthetist’s expertise and the limited methods to quantify design choices. This thesis investigates the lower-limb prosthetic fitting process and the importance of the socket design. Previous research has taken local stiffness of the limb to provide prosthetists with more...
The energy harvesting performance of oscillating airfoils is studied using a discrete vortex model (DVM) with a leading-edge separation criterion. The airfoil undergoes a combined sinusoidal heaving and pitching motion at reduced frequencies of k = 0.06 − 0.16, with heaving amplitude of h0 = 0.5c, and pitching amplitude of...
The High Altitude Liquid Engine (HALE) team is developing of a 2000 lbf thrust liquid propellant engine for a flight vehicle capable of breaching the Karman Line (100 km in altitude). As part the development of this flight vehicle, this research focuses on the design and characterization of a novel...
The ultimate goal of this work is to analyze and compare two predictive models of thermal profile in laser processing of materials. An analytical method that uses closed-form equations to represent a geometric model of a laser heat source will be contrasted with a commercial computational fluid dynamics code that...
Rear brake calipers are a critical component of the brake system within a vehicle. Brake calipers function by clamping against the brake rotor when the brake pedal is pressed by the driver and thus results in deceleration of the vehicle. This thesis aims to design and develop custom rear brake...
Much like wind energy in its early years, marine energy has vast potential, and wave energy converter (WEC) concepts are constantly in development. Consequently, wave energy faces many challenges for expansion and has a wide-ranging design space of WEC concepts. The large design space demands new methods for understanding the...
Sensing is a significant engineering science which quantify parameters from the physical world and discover the physics running behind the measurement process. Optical sensing makes use of electromagnetic waves from infrared to ultraviolet on the light spectrum as a medium to measure variables, such as position, temperature and strain. Image...
For this project, we designed a soot modeling software to produce a full particle density function. This model uses the Direct Simulation Monte Carlo with a full conditioning particle selection method to capture soot nucleation and coagulation in a diffusion flame. We investigate the use of graphic processing units as...
In this work, a fully automated approach to synthesis Metal-Organic Frameworks is presented. We use graph to represent the structure of Metal-organic Frameworks and use graph grammars which are backbone rules and functional group rules to generate metal-organic framework. For a given parameter value of the user defined metal-organic framework,...
A six degree of freedom (6DOF) point-absorber wave energy converter (WEC) called LUPA is being developed at Oregon State University. This research focused on analyzing a full- scale LUPA, called LUPA20, to answer the following questions: 1) How does a full-scale WEC perform due to various factors; 2) What are...
This thesis follows two studies performed with simple robots. The first follows a robot interacting with eight improvisers to create scenes and perform five isolated gestures (towards, away, sideways, spin, and circle) for interpretation. The second follows a group of three robots performing the same five isolated gestures at two...
Oscillating foil energy harvesters are analyzed at optimal reduced frequencies (𝑘=𝑓𝑐/𝑈) to determine how the leading edge radius of curvature affects leading edge separation. The understanding of leading edge separation and its behaviors is critical to predicting the transient lift profile of an airfoil. The separation is therefore also critical...
High-potential molecules derived from biomass sources may suitably replace or supplement traditional nonrenewable hydrocarbon fuels to reduce pollution and fuel processing costs. Due to expensive and time-consuming property testing, models that predict key properties from optical data would initially vet potential additives before investment and bench-scale testing. Attenuated Total Reflection...
The operation of gas turbine engines depends on the reliable ignition of fuel/air mixtures. Gas turbine engines are commonly used as commercial and military aviation power plants. However, consistent ignition within gas turbine engines is still a problem, especially for more challenging operating conditions such as emergency operations. This work...
Smoldering can play a dangerous role in the ignition and spread of wildfires. Naturally occurring fuels consist of multiple layers of organic materials with varying particle sizes due to differences in decomposition stages with fuel depth, yet the influence of particle size on burning behavior is poorly understood. Previous research...
The matrix compression behavior is assumed similar to tension, and many material's elastic and damage parameters are considered equal in tension and compression but experimentally not explored. This assumption leads to unrealistic or very far from the actual behavior of the matrix under compression. Moreover, the pre-existing implemented Abaqus models...
The health and environmental impacts associated with traditional methods of household cooking and heating have driven the development and dissemination of many types of improved cookstoves and fuels. However, adoption rates, household cooking practices, and even household ventilation can directly influence the magnitude of real-world impacts. Given the highly contextual...
Considering human factors in early engineering design stages can improve expensive late stage processes, facilitate user safety, improve product quality and help reduce the need for physical prototyping. Currently, car pillar design (the vertical pillars between windows which connect the roof and car body) provide safety for the passengers in...
The study focuses on how to use entertainment method approach to prompt people with best practices for COVID safety. During COVID times, there have been many robots deployed in public places such as social distancing enforcer or a robot that provide facial masks, but few investigations have been done to...
In this work, I developed a six degree of freedom flight simulator specific to liquid engine launch vehicles. This flight simulator improves upon available software by accounting for liquid engine specific phenomena such as tank pressurization, liquid engine performance, and center of gravity modeling. Additionally, I implemented methods for optimization...
Most accidents and malfunctions in complex engineered systems are attributed to human error. However, a closer inspection would reveal that such mishaps often emerge as a result of poor design and human- and component-related vulnerabilities acting together. To fully understand and mitigate potential risks, the effects of such interactions between...
Digital image correlation (DIC) uses pairs of images, one in a reference state and one after in situ manipulation of the object, to measure full-field displacements and strains by tracking the motion of small image subsets. Subset selection is always a crucial part of DIC technique as it has a...
Wicking action refers to the movement of a liquid through a porous or a structured surface via capillary action. This phenomenon is affected by surface geometry, such as the wick thickness and pore size of the wick, as well as fluid properties, such as viscosity and surface tension of the...
Deep rolling is a surface finishing technique that is widely used in several industries, specifically aerospace and automotive. Extending fatigue life by inducing compressive residual stresses at and below the deep rolled surface has been the primary driving force behind this newfound popularity. Understanding the development of the residual stresses...
A nickel-based Hastelloy C22 powder with a nominal composition of Ni-21.30Cr-13.36Mo-1.92Co-2.94W-3.85Fe-0.23Mn-0.3V(wt%) and particle size distribution of D₁₀=23.8±0.3 μm, D₅₀=37.5±0.2μm, and D₉₀=59.3±1.1 μm was gas atomized to be used as a feedstock in Laser Powder Bed Fusion (LPBF). In this study, laser power and scanning speed were optimized to manufacture specimens...