Mechanical Engineering Commons^™

A Study On Scaling Floating Offshore Wind Turbine Geometry And Hydrostatics With Increasing Turbine Size, Samuel Davis

Honors College

Floating offshore wind offers a clean and sustainable alternative to fossil fuels for the future of energy production. In Maine in particular, there is a great opportunity to take advantage of the wind resource off the coast and become a global leader in offshore wind. With the Maine coastal waters being too deep for fixed-bottom turbine structures, floating platforms that support the turbines have the opportunity to gain traction as the technology matures. As wind turbines increase in size and capacity, the floating hulls must also increase in size. The research presented in this thesis aimed to calculate and examine …

The Performance Assessment Of A Small Lighter-Than-Air Vehicle For Earth Science Remote Sensing Missions, Maxwell F. Burtis

Honors College

This summer, a lighter-than-air (LTA) drone was tested in Alaska to measure glacier bedrock fracture density and orientation. Five flights were made in low wind conditions, and the directional stability of the airship made it too challenging to control in flight to realistically acquire useful image sets. The directional stability of the airship, when compared to an actively stabilized consumer-grade quadcopter was inferior. Flight logs and GPS data from the GPS on the LTA drone were analyzed and a quantitative assessment of the observed instability was made. The yaw axis and pitch were analyzed, and the yaw axis instability was …

Effects Of Process Parameters And Meso-Structures On Dissipative Properties Of Additively Manufactured Structures, Peter Berube

Honors College

With approximately 5.9 million vehicular collisions in the United States per year, the ability of a vehicle to absorb energy during a collision is critical to reducing the likelihood and severity of injuries. A primary means to absorb energy during a collision is a crush tube, which is a predominantly-prismatic-shaped, metallic structure located at the front or rear of a vehicle intended to absorb energy by progressively buckling in addition to dissipating energy, crush tubes must be light weight to reduce vehicular green-house gas emissions, resilient to fatigue, resilient to environmental exposure, and economically feasible to manufacture. Historically, these competing …

Efficiency Of The United States Navy's Mid-Air Refueling System: Do The Best Pilots In The World Use The Best Equipment?, Austin Westfield

Honors College

The United States Navy has used the Drogue refueling system since the 1950’s. This system, while incredibly effective, has design elements that, if improved upon, could save the Navy millions of dollars per year. For my thesis project within the University of Maine Honors College, I studied the drag characteristics of two models of a refueling apparatus. One model mirrored the current Navy design and the other was based on my sensor array design implemented within my Mechanical Engineering Capstone team project, which was to design, build, and fly a remote-controlled (RC) aircraft that deployed and retracted a towed array …

A Shoulder Mechanisms For Assisting Upper Arm Function With Distally Located Actuators, Michael Jones

Honors College

This thesis presents a new design for a shoulder assistive device based on a modified double parallelogram linkage (DPL). The DPL allows for active support of the arm motion in the sagittal plane, while enabling the use of a distally located motor that can be mounted around the user’s waist to improve the weight distribution. The development of the DPL provides an unobtrusive mechanism for assisting the movement of the shoulder joint through a wide range of motion. This design contains three degrees-of-freedom (DOFs) and a rigid structure for supporting the arm. The modified DPL uses a cable-driven system to …

An Upper Extremity Exoskeleton Utilizing A Modified Double Parallelogram Linkage Mechanism With Proximally Located Actuators, Connor Bouffard

Honors College

The shoulder joint is an extremely complex joint, with a wide range of motion (ROM), which makes designing an upper extremity exoskeleton a complicated task. This thesis presents a 3-degree-of-freedom (DOF) exoskeleton with a modified double parallelogram mechanism (DPM) that fits any wearer independent of their biological frame. The DPM is remarkably useful in wearable robotics. The mechanism creates a remote center of rotation about the shoulder joint while remaining unobtrusive and not colliding with the wearer’s body. Its fixed link lengths, however, requires it to be specially fitted to each individual user. This is inconvenient for most exoskeletons that …

Design Of A Low Impact Canoe Portage System For The Hirundo Wildlife Refuge, Anthony Kingston

Honors College

The Hirundo Wildlife Refuge has requested a canoe portage system to be built. Before the system can be built, it is necessary to research the different designs that Hirundo can pursue. In this document, three different routes that Hirundo can pursue are designed. In order to decide what route is the best route, Hirundo requested that each route fit certain design criteria, which are also shown in the document. This thesis concludes with a recommendation for Hirundo of which design to pursue.

Modeling Of A Continuously Variable Transmission And Clutching Of A Snowmobile, Camerin Michael Seigars

Honors College

This thesis describes the conceptual operation of a continuously variable transmission (CVT) and develops a model of a CVT system. The purpose is to form a framework for understanding how CVTs work, what factors go into their design, why they are used on almost all modern snowmobiles, and how they can be tuned for better performance. By developing a model using rigid body analysis, computer modeling, and a list of structured equations, a CVT can be tuned more efficiently. The model is used to calculate values difficult or tedious to evaluate by hand with visual aide for clearer understanding of …

Analysis Of Flow Of Compressed Natural Gas Through A Fuel Injector, Erin E. Eldridge

Honors College

The purpose of this thesis is to discuss the determination of the mass flow rate of compressed natural gas through a Delphi Multec CNG Injector. Three methods are used to find the mass flow rates at various pressures. First, SolidWorks Flow Simulation is employed to calculate the mass flow rate with computational fluid dynamics. An analytical solution to the problem is also presented. Finally, experimental results from a previous year’s Capstone team are presented. Fuel flow curves are provided to compare the results from each methodology. The results from the SolidWorks Flow Simulation and analytical calculation agree at the extrema …

Dynamic Modeling Of A Catamaran Using A Lagrangian Approach, Tamara R. Thomson

Honors College

In this thesis, the development and application of a dynamic model of the 2016 Autonomous Boat Team’s catamaran are discussed. The model is two dimensional and describes the motion of the boat in a calm freshwater environment. The linear and rotational equations of motion used in the model were derived by employing Lagrangian dynamics, and the thrust of the motors and drag of the hulls were found through experimentation. The resulting equations are ma = (1/2) ∙ p ∙ x²C_DfA+2F and 1a = (b/16) ∙ p ∙𝜃²C_DrA+F₂ ∙ (b/2) - F …

Modeling Of A Continuously Variable Transmission And Clutching Of A Snowmobile, Camerin Michael Seigars

Honors College

This thesis describes the conceptual operation of a continuously variable transmission (CVT) and develops a model of a CVT system. The purpose is to form a framework for understanding how CVTs work, what factors go into their design, why they are used on almost all modern snowmobiles, and how they can be tuned for better performance. By developing a model using rigid body analysis, computer modeling, and a list of structured equations, a CVT can be tuned more efficiently. The model is used to calculate values difficult or tedious to evaluate by hand with visual aide for clearer understanding of …

The Finite Element Analysis And Optimization Of A Circumcision Device For Hiv Prevention In Sub-Saharan Africa, Abraham W. Hamilton

Honors College

Millions of people around the world are affected by HIV. Studies have demonstrated that the circumcision of heterosexual males leads to an approximate 60% reduction in the potential for the contraction of the virus from a female partner. Current surgical circumcision techniques are not feasible on the required scale in remote settings. An innovative solution is needed. The goal of this project is to develop a safe and effective device for large-scale circumcision efforts in remote regions of sub-Saharan Africa. This thesis will focus specifically on the analysis and optimization of the device. A full scale finite element analysis of …

Analysis Modeling And Optimization Of A Smart Sulky, Nicholas C. Noble

Honors College

For several hundred years, the Standardbred harness racing industry has remained relatively unchanged. The sulkies pulled by the horses have seen only minor changes. New construction techniques and lighter materials have allowed sulkies to become lighter and generally faster. However, there is currently no sulky that uses a modern control system to adapt to changing racetracks, horses, and drivers. A Smart Sulky would be able to accomplish these things. The Smart Sulky would be capable of measuring changes in the movements of the horse and compensate for rotational movement and vibration, which the horse transfers to a conventional sulky. The …

Development Of Oxidizer Flow Control For Use In Hybrid Rocket Motors Of The Scientific Sounding Rocket Scale, Luke Saindon

Honors College

To successfully build a rocket engine with variable thrust you must devise a reliable and robust oxidizer flow control system. The goal of this thesis is to contribute to the goal of building a variable thrust (throttled) hybrid rocket engine, which could eventually be used to power scientific sounding rockets. A variable thrust hybrid engine would increase reusability, flexibility, and capability of almost any small rocket.

Specifically, this thesis work regards the development of the closed loop oxidizer flow control system. To do this, a small test rig was built in the lab that consists of all the components in …