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Mechanics Desktop Lab Equipment, Dante Azpilcueta, Quentin F. Mormann, Arfan Ansar
Mechanics Desktop Lab Equipment, Dante Azpilcueta, Quentin F. Mormann, Arfan Ansar
Mechanical Engineering
This paper overviews the design, implementation and testing of a senior project designed to fix the issue of there being no lab equipment or space for content pertaining to mechanic of materials topics. This is of concern as Cal Poly is reorganizing content as it switches to the semester system and is in need of labs for this material. The solution found was to create a portable miniature universal test machine that could be carted into non-lab classrooms. The goal was to create a device that was low-cost, modifiable, durable, easy to manufacture and repair as these were the qualities …
An Experimental Analysis Of Thin Sheet Metal Bending By Ultrafast Laser Peen Forming, Bryce J. Tessmann
An Experimental Analysis Of Thin Sheet Metal Bending By Ultrafast Laser Peen Forming, Bryce J. Tessmann
All Theses
This study demonstrates the viability of femtosecond laser peen forming for bidirectional sheet metal bending. Ultrafast laser forming is a valuable method thanks to its flexibility, negation of springback, no need for a confining or protective layer, and minimalization of thermal degradation in comparison to other forming processes. However, femtosecond lasers have traditionally been believed to be unsuitable for laser forming in comparison to nanosecond lasers, particularly bidirectional bending, because the induced shock waves were expected to be weak. Conversely, in this study it is elucidated that the femtosecond laser-induced shock waves are extremely strong (several hundred GPa) but the …
Mechanical Characterization Of Anisotropic Fused Deposition Modeled Polylactic Acid Under Combined Monotonic Bending And Torsion Conditions, Aaron T. Santomauro
Mechanical Characterization Of Anisotropic Fused Deposition Modeled Polylactic Acid Under Combined Monotonic Bending And Torsion Conditions, Aaron T. Santomauro
Honors Undergraduate Theses
Mechanical strength of polylactic acid (PLA) is increasingly relevant with time because of its attractive mechanical properties and 3D printability. Additive manufacturing (AM) methods, such as fused deposition modeling (FDM), stereolithography (SLA), and selective laser sintering (SLS), serve a vital role in assisting designers with cheap and efficient generation of the desired components. This document presents research to investigate the anisotropic response of multi-oriented PLA subjected to multiple monotonic loading conditions. Although empirical data has previously been captured for multi-oriented PLA under tensile and compressive loading conditions, the data has yet to be applied with regard to a representative component …
Investigation Of An Isotruss Structure As A Compliant Member Used In Bending And Torsion, Jens Garret Jacobson
Investigation Of An Isotruss Structure As A Compliant Member Used In Bending And Torsion, Jens Garret Jacobson
Theses and Dissertations
An investigation of IsoTruss structures in bending and torsion was conducted. A model was developed in ANSYS APDL where bay length and longitudinal member to helical member cross-sectional area ratio could be varied while holding the diameter constant. The model was validated using previously reported values from analytical models and empirical data. The model was used to make predictions of a specific geometry that was manufactured, tested and compared against the model. 12 specimens were built and tested. In flexure, empirical data had a percent error with respect to the model ranging from 10.9 to 65.4% with one outlier at …
Detecting Laminate Damage Using Embedded Electrically Active Plies – An Analytical Approach, Amany Micheal, Yehia Bahei-El-Din
Detecting Laminate Damage Using Embedded Electrically Active Plies – An Analytical Approach, Amany Micheal, Yehia Bahei-El-Din
Centre for Advanced Materials
Assessment of damage initiation and progression in composite laminates with embedded electrically active plies is modeled. Utilizing electrically active layers embedded in composite laminates as damage sensors is proposed by several researchers and is mainly assessed experimentally. Sensing damage using embedded electrically active plies is generally preferred over the use of surface mounted PZT wafers since the range of the latter is limited to a very narrow area underneath the surface, while multiple damage mechanisms can generally be found in several plies of the laminate. The solution presented invokes two levels of analysis. Firstly, on the laminate level, applied membrane …
Flexural Creep Behavior Of Adhesively Bonded Metal And Composite Laminates, Hasan M. Nuwayer
Flexural Creep Behavior Of Adhesively Bonded Metal And Composite Laminates, Hasan M. Nuwayer
Wayne State University Dissertations
Adhesively bonded structures exhibit time dependent behavior when subjected to constant load (creep). In this investigation, long-term creep behavior of adhesively bonded aluminum and carbon fiber composite beams under flexural loading was investigated. Three point bending test was selected because of its simplicity and the fact that bending stresses are quite common. In this study, two types of adhesively bonded beam specimens were tested: specimens prepared by adhesively bonding two aluminum beams and specimens prepared by adhesively bonding two unidirectional carbon fiber laminated beams. Accelerated creep tests were performed at higher temperatures up to 60 °C and deflection was measured …
Swagelok's Hand Tube Bender, Chapin Hutama, Seth Bills, William Mcconnell, Tyler Brown
Swagelok's Hand Tube Bender, Chapin Hutama, Seth Bills, William Mcconnell, Tyler Brown
Williams Honors College, Honors Research Projects
In our project, we are assigned to develop a hand tube bender that is able to bend medium, high pressure, and standard 1/4” and 3/8” tubing. The bender also shall be capable of being used with two hands without the aid of a bench vise and have provisions for use in a bench vise for convenience. The bender shall not damage the tube during bending and induce a maximum of 8% ovality in the bent tubing. In addition, the cost of the bender shall be less than the existing hand tube bender and be resistant to rusting from ordinary use. …
Smartwalker – Rolling Walker Instrumentation And Data Acquisition System Development To Monitor, Visualize And Store Rolling Walker Usage Data, Mauricio Jaguan Nieves
Smartwalker – Rolling Walker Instrumentation And Data Acquisition System Development To Monitor, Visualize And Store Rolling Walker Usage Data, Mauricio Jaguan Nieves
Mechanical and Aerospace Engineering Theses
The Smart Walker project was designed to fill a necessity of monitoring in real time the use of rolling walkers (RW) and study the causes that contribute to the high rate of fallings among its users. The main objectives of the project were to measure the major forces applied by RW users in real time and store it safely for further analysis. The first prototype of the Smart Walker includes the measurement of axial load, torque and gripping force applied on the handle as well as acceleration and rotation angles while it is being used. The axial load was measured …
Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell
Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell
Faculty Publications
Similar to the general class of metamaterials, compliant arrays (CAs) are engineered from an array of subelements that combine to produce a response that is typically not available from a at panel made of a single material. As such, analysis and design of CA systems requires the integration of both the material and geometrical properties of the array. This paper proposes a convenient and efficient method of combining these essential elements using analytically derived shape factors for bending modes. The approach is validated experimentally, and used to demonstrate large regions of previously inaccessible property combinations in material selection charts that …
Solar Turbines Creep Test Fixture, Rene Maciel, Eric Nelson, Chris Ewald
Solar Turbines Creep Test Fixture, Rene Maciel, Eric Nelson, Chris Ewald
Mechanical Engineering
No abstract provided.
Strain Energy And Lateral Friction Force Distributions Of Carbon Nanotubes Manipulated Into Shapes By Atomic Force Microscopy, Mark C. Strus, Roya R. Lahiji, Pablo Ares, Vincente Lopez, Arvind Raman, Ron R. Reifenberger
Strain Energy And Lateral Friction Force Distributions Of Carbon Nanotubes Manipulated Into Shapes By Atomic Force Microscopy, Mark C. Strus, Roya R. Lahiji, Pablo Ares, Vincente Lopez, Arvind Raman, Ron R. Reifenberger
Other Nanotechnology Publications
The interplay between local mechanical strain energy and lateral frictional forces determines the shape of carbon nanotubes on substrates. In turn, because of its nanometer-size diameter, the shape of a carbon nanotube strongly influences its local electronic, chemical, and mechanical properties. Few, if any, methods exist for resolving the strain energy and static frictional forces along the length of a deformed nanotube supported on a substrate. We present a method using nonlinear elastic rod theory in which we compute the flexural strain energy and static frictional forces along the length of single walled carbon nanotubes (SWCNTs) manipulated into various shapes …
Piezoresistive Models For Polysilicon With Bending Or Torsional Loads, Gerrit T. Larsen
Piezoresistive Models For Polysilicon With Bending Or Torsional Loads, Gerrit T. Larsen
Theses and Dissertations
This thesis presents new models for determining piezoresistive response in long, thin polysilicon beams with either axial and bending moment inducing loads or torsional loads. Microelectromechanical (MEMS) test devices and calibration methods for finding the piezoresistive coefficients are also presented for both loading conditions. For axial and bending moment inducing loads, if the piezoresistive coefficients are known, the Improved Piezoresistive Flexure Model (IPFM) is used to find the new resistance of a beam under stress. The IPFM first discretizes the beam into small volumes represented by resistors. The stress that each of these volumes experiences is calculated, and the stress …
Elastic Modulus Of Amorphous Sio2 Nanowires, Hai Ni, Xiaodong Li, Hongsheng Gao
Elastic Modulus Of Amorphous Sio2 Nanowires, Hai Ni, Xiaodong Li, Hongsheng Gao
Faculty Publications
Amorphous SiO2 nanowires with diameter ranging from 50 to 100 nm were synthesized using chemical vapor deposition(CVD) under an argon atmosphere at atmospheric pressure. Nanoscale three-point bending tests were performed directly on individual amorphous SiO2 nanowires using an atomic force microscope (AFM).Elastic modulus of the amorphous SiO2 nanowires was measured to be 76.6±7.2GPa, which is close to the reported value of the bulk SiO2 and thermally grown SiO2 thin films, but lower than that of plasma-enhanced CVD SiO2 thin films. The amorphous SiO2 nanowires exhibit brittle fracture failure in bending.