Engineering Commons^™

Cart Loader, Hayelom Fitsum, Dalveer Grewal, Ishan Kumar, Sean Mccauley, Nick O'Brien

Mechanical Engineering Senior Theses

For this senior design project, the team partnered with a startup, Dishcraft Robotics, to design and create a device that would decrease the time it takes to unload and load their products in and out of a truck. The team’s design, Cart Loader, consists of an aluminum structure that is able to hold their products. Outfitted with a rail system on the truck and the liftgate, the Cart Loader can move onto the liftgate and roll inside the truck, where the products can then be rolled off the Cart Loader. There was extensive finite element analysis done to ensure that …

Structural Sizing Of Post-Buckled Thermally Stressed Stiffened Panels, Walid Arsalane

Theses and Dissertations

Design of thermoelastic structures can be highly counterintuitive due to design-dependent loading and impact of geometric nonlinearity on the structural response. Thermal loading generates in-plane stresses in a restrained panel, but the presence of geometric nonlinearity creates an extension-bending coupling that results in considerable transverse displacement and variation in stiffness characteristics, and these affects are enhanced in post-bucking regimes. Herein a methodology for structural sizing of thermally stressed post-buckled stiffened panels is proposed and applied for optimization of the blade and hat stiffeners using a gradient-based optimizer. The stiffened panels are subjected to uniform thermal loading and optimized for minimum …

Comparison Of Johnson-Cook And Linear Elastic-Perfectly Plastic Material Models For Ballistic Impact Case, Logan J. Callahan, Marella Failla, Harrison Williams

ME 4233/6233 Fundamentals of FEA

In an effort to characterize the linear elastic-perfect plastic (J2) and Johnson-Cook (JC) Strengthening and Damage material models for an Aluminum target material being struck by a steel penetrator, finite element analysis (FEA) will be used to simulate the residual velocities from ballistic impacts, using various velocities of the penetrator. The object is to define the point at which the J2 material model is no longer accurate and therefore requires the use of the JC material models.

Numerical Analysis Of Taylor Impact With Various Nose Shapes, Jean C. Santiago Padilla, Erik M. Chappell

ME 4233/6233 Fundamentals of FEA

The Taylor impact test is an experimental technique used to determine dynamic material response and to validate constitutive models used in numerical simulations. It generally consists of shooting a cylinder rod of a select material against a rigid target at different velocities. After impact, the plastic deformation of the cylinder is recorded and is directly compared to numerical predictions. Another application for Taylor impact was proposed by Li et al. (2021) where the nose shape of the cylinder is modified to create different loading environments that can test electronic equipment in penetration weapons. FEA models where designed in ABAQUS/Explicit to …

Prediction Of Residual Stresses In L-Pbf Ti-6al-4v Fatigue Specimens Using A Thermo-Mechanical Finite Element Model, Haley Petersen, Brad J. Sampson

ME 4233/6233 Fundamentals of FEA

Laser Powder Bed Fusion (L-PBF) is an additive manufacturing process that is becoming widely adopted in the automotive, aerospace, and biomedical industries. It uses a laser to melt metal in the form of powder to build parts in a layer-by-layer fashion based on an imported CAD geometry. The constant remelting of previous layers can produce unwanted thermally induced residual stresses in the part due to large thermal gradients, which can drastically reduce the fatigue life of the material. Predicting these residual stresses within the as-built part would be advantageous because one could better understand how the part will perform in …

Finite Element Model Of The Pediatric Hip Joint During The Barlow Maneuver, Christina M. Zlock

Doctoral Dissertations and Master's Theses

Developmental Dysplasia of the Hip is the dysplasia or dislocation of an unstable femoral head in the acetabulum of the pelvis. This is a result of an abnormal or underdeveloped growth of the acetabulum and triradiate cartilages and/or an out of place and uncentered femoral head in the acetabulum. This underdevelopment, if not diagnosed and treated at an early age, may lead to abnormal and pain and osteoarthritis later in life. A common step in diagnosis is to perform a physical examination of the hip, one method is the Barlow maneuver.

The aim of the project is to use healthy …

Understanding The Nonlinear Dynamics Governing Vertical-Lift Vehicles With Variable-Speed, Fixed Rotors, Stephanie Vavra, Micah Busboom, Aleea Stanford, Keegan Moore

UNL Student Research Days Posters, Undergraduate

Problem: Traffic significantly limits travel in urban areas. • The NASA Urban Air Mobility Project is developing an air taxi as an alternative mean of transportation (Fig. 1).

Challenge: Operating rotors at different frequencies may cause the cabin to vibrate at high amplitudes. Such effects are currently unknown.

Objective: Understand the effect of variable speed rotors on passenger comfort.

From the reduced-order modeling simulations, it can be assumed that counteracting the rotor speed in-balances can reduce the displacement and vibrations experienced at the center of the wing. In other words, should a rotor not maintain its optimal operation speed, reducing …

Ljm Rc Baja Vehicle Project Chassis And Suspension, Paul Lervick

All Undergraduate Projects

An RC car was designed, analyzed, and manufactured to compete in the ASME RC Baja competition. The focus was to optimize the suspension and chassis components to minimize the weight while maintaining the structural strength of the components which would intern supplement the overall speed and stability of the vehicle. Other components were the responsibility of the teammate Cam Jamison. To complete this there was extensive research done on Traxxas RC cars and what went into making a high-performing vehicle that would compete well in the 3 races that comprise the competition (slalom, sprint, and obstacle course). There were then …