Applied Mechanics Commons^™

A Single-Stage Passive Vibration Isolation System For Scanning Tunneling Microscopy, Toan T. Le

Master's Theses

Scanning Tunneling Microscopy (STM) uses quantum tunneling effect to study the surfaces of materials on an atomic scale. Since the probe of the microscope is on the order of nanometers away from the surface, the device is prone to noises due to vibrations from the surroundings. To minimize the random noises and floor vibrations, passive vibration isolation is a commonly used technique due to its low cost and simpler design compared to active vibration isolation, especially when the entire vibration isolation system (VIS) stays inside an Ultra High Vacuum (UHV) environment. This research aims to analyze and build a single-stage …

Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe

Mechanical Engineering

Reinventing the Wheel selected tires and designed wheels for the 2018 Cal Poly, San Luis Obispo Formula SAE combustion vehicle. Available tire options were evaluated for steady-state and transient performance as well as vehicle integration. A single-piece composite wheel with hollow spokes was designed to meet stiffness, strength, and tolerance requirements. A detailed study of wheel loading and geometric structural efficiency was performed. Finite element analysis was used to iterate the geometry and laminate. A two-piece male mold was designed and machined to manufacture the wheel. Removable silicone inserts were used to create the hollow spokes.

Experimental Building Demonstration Model With Viscous Fluid Dampers, Blake Thomas Reeve, Brianna Jean Kufa, Aden Malek Stepanians, Sophie Carmion Ratkovich

Architectural Engineering

The Architectural Engineering major places a heavy emphasis on structural dynamics and the role of wind and seismic loading in building analysis and design. Buildings of high importance that are critical to community function, such as hospitals, often utilize supplemental damping devices like supplemental viscous fluid dampers or base isolators to reduce the overall demands on the structural system. The design and analysis of these dampers are typically not taught at the undergraduate level, and is frequently performed by mechanical engineers, in lieu of structural engineers.

To better understand and research building behavior with supplemental damping devices, our multi-disciplinary team …

Modification Of A Draw Bar Type Arena Harrow To Three Point Mounted Type Harrow, Clayton Alan Brown

BioResource and Agricultural Engineering

This senior project will be the design, and construction of a three point hitch to be attached to a draw bar type spike tooth harrow. Currently used by the Cal Poly Rodeo Team to cultivate their arena before performances, and practices.

The attachment will allow the harrow to be pulled in both directions to create different types of soil affects.

Also the fabrications has a minimal budget so the majority of the materials will be scrap material already in position of the rodeo team or donated to the project.

Lightweight Uav Launcher, Ben Miller, Christian Valoria, Corinne Warnock, Jake Coutlee

Mechanical Engineering

This report discusses the design, construction, and testing of a lightweight, portable UAV launcher. There is a current need for a small team of soldiers to launch a US Marine Tier II UAV in a remote location without transport. Research was conducted into existing UAV launcher designs and the pros and cons of each were recorded. This research served as a basis for concept generation during the initial design development stage. It was required that the design weigh less than 110 lbs, occupy a smaller volume than 48" x 24" 18" in its collapsed state, be portable by a single …

Vibration-Based Health Monitoring Of Multiple-Stage Gear Train And Differential Planetary Transmission Involving Teeth Damage And Backlash Nonlinearity, Andrew Patrick Sommer

Master's Theses

The objective of this thesis is to develop vibration-based fault detection strategies for on-line condition monitoring of gear transmission systems. The study divides the thesis into three sections. First of all, the local stresses created by a root fatigue crack on a pinion spur gear are analyzed using a quasi-static finite element model and non-linear contact mechanics simulation. Backlash between gear teeth which is essential to provide better lubrication on tooth surfaces and to eliminate interference is included as a defect and a necessary part of transmission design. The second section is dedicated to fixed axis power trains. Torsional vibration …