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Health Monitoring for Damage Initiation & Progression During Mechanical Shock in Electronic Assemblies
(2009-02-23)
Electronic products may be subjected to shock and vibration during shipping, normal usage and accidental drop. Highstrain rate transient bending produced by such loads may result in failure of fine-pitch electronics. Current ...
Heuristic Optimization Methods for the Characterization of Dynamic Mechanical Properties of Composite Materials
(2009-02-23)
Generally speaking, of the fundamental dynamic mechanical properties - mass, damping, and stiffness, damping is usually the most difficult to quantify. This is perhaps particularly true for composite materials which tend ...
Static, Dynamic and Acoustical Properties of Sandwich Composite Materials
(2009-02-23)
Sandwich composite materials have been widely used in recent years for the construction of spacecraft, aircraft, and ships, mainly because of their high stiffness-to-weight ratios and the introduction of a viscoelastic ...
Prognostics Health Management and Damage Relationships of Lead-Free Components in Thermal Cycling Harsh Environments
(2008-09-09)
There has been a growing interest in the area of health monitoring of electronics in order to predict the failure and provide warnings. Existing Prognostics Health Management methodologies are very reactive in nature and ...
Relative Positioning of Unmanned Ground Vehicles Using Ultrasonic Sensors
(2008-09-09)
In this thesis, a Global Positioning System/Inertial Navigation System (GPS/INS) is developed and applied to a tracked Unmanned Ground Vehicle (UGV) to provide estimates of position, heading, and velocity. The navigation ...
Parameter Estimation Techniques for Determining Safe Vehicle Speeds in UGVs
(2008-09-09)
This thesis develops simplified equations to predict a velocity in which vehicle rollover or tire saturation occurs. These equations are functions of different vehicle parameters that are important to vehicle handling ...
Adaptive Control of a Farm Tractor with Varying Yaw Properties Accounting for Actuator Dynamics and Nonlinearities
(2008-09-09)
Two adaptive control algorithms for the automatic steering control of a farm tractor with varying hitch forces are developed. Tractors can be configured many different implements, and implements interact with the soil in ...
Finite Element Analysis of Three-Dimensional Elasto-Plastic Sinusoidal Contact and Inclusion in a Multi-Scale Rough Surface Contact Model
(2008-09-09)
Researchers have developed many models to simulate the elasto-plastic contact of spheres. However, there does not appear to exist a closed-form analytical model for elasto-plastic three dimensional sinusoidal contact. This ...
Damage Prediction of Lead Free Ball Grid Array Packages Under Shock and Drop Environment
(2008-09-09)
The fatigue and damage of solder joints and also the potential for interface failure within BGA packages are caused by thermal cycling. In case of portable electronic products, fatigue is caused by repetitive drop and shock ...
Design and Analysis of Air and Coolant Control for a Polymer Electrolyte Membrane Fuel Cell
(2008-09-09)
The polymer electrolyte membrane (PEM) fuel cell is an alternative engine that can potentially replace the internal combustion engine in the vehicles of the future. When hydrogen, stored in a tank, and oxygen, from the ...