Mechanical Engineering Commons^™

Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang

Electronic Theses and Dissertations

Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …

Modelling, Sensing, And Control Of Weld Beads In Gravity Aligned And Non-Gravity Aligned Orientations For Wire Arc Additive Manufacturing, Joshua J. Penney

Doctoral Dissertations

Wire Arc Additive Manufacturing (WAAM) has recently developed into a viable manufacturing process for large, complex metal parts. The WAAM process uses a Gas Metal Arc Welding (GMAW) torch mounted to an automated motion platform to execute a predetermined path plan based on a desired CAD geometry. As the desired geometry becomes more complex, it is advantageous to utilize out-of-position welding techniques used by human welders to stabilize the weld pool during the deposition of large overhangs. To ensure part accuracy and quality, adding layers of real-time control to manage various aspects of the WAAM process is critical. First, a …

Micro-Manipulation Using Learned Model, Matthew A. Lyng, Benjamin V. Johnson, David J. Cappelleri

The Summer Undergraduate Research Fellowship (SURF) Symposium

Microscale devices can be found in applications ranging from sensors to structural components. The dominance of surface forces at the microscale hinders the assembly processes through nonlinear interactions that are difficult to model for automation, limiting designs of microsystems to primarily monolithic structures. Methods for modeling surface forces must be presented for viable manufacturing of devices consisting of multiple microparts. This paper proposes the implementation of supervised machine learning models to aid in automated micromanipulation tasks for advanced manufacturing applications. The developed models use sets of training data to implicitly model surface interactions and predict end-effector placement and paths that …

Physical Modeling Of Lithium-Ion Aging For Automotive Applications, Anurag Kamal

Dissertations, Master's Theses and Master's Reports

This thesis extends the full-scale electrochemical model for a Lithium-ion battery based on the porous electrode theory to incorporate aging mechanisms of solid electrolyte interface formation, cyclic electrode degradation, and lithium plating during overcharge, automotive vibrations, mechanical stress, and cell temperature, as reported in the existing literature. Further, the thesis presents the scope of the parameters used in the model to enable designers to extend the equations for new mechanisms and variability of other parameters.

An increased set of equations makes the complexity of the model even higher, and it would be very computationally complex to simulate this model. This …

Thermoelectric System Modeling And Design, Buddhima Pasindu Gamarachchi

Boise State University Theses and Dissertations

Thermoelectric generators (TEGs) convert heat to electricity by way of the Seebeck effect. TEGs have no moving parts and are environmentally friendly and can be implemented with systems to recover waste heat. This work examines complete thermoelectric systems, which include the (TEG) and heat exchangers or heat sinks attached to the hot and cold sides of the TEG to maintain the required temperature difference across the TEG. A 1-D steady state model is developed to predict the performance of a TEG given the required temperatures and device dimensions. The model is first validated using a 3-D model and then is …

Modeling Of The Interior Electric Field In Photovoltaic Cells, Tara Jeatran

The Journal of Undergraduate Research

With the emergence of photovoltaic technologies, there is a strong technological demand for high-performance photovoltaic devices. One of the most promising device concepts developed at SDSU is organic-based photovoltaic cells. The performance of the PV cells is controlled by charge generation and charge separation, and charge transportation processes. Extraordinary control over the properties of the organic photovoltaic materials will be needed in order for this research to succeed. Therefore, the interior electric field and the macro electric properties of the system are the foundation behind these facts and are critical properties on their performance. In this paper, the fundamentals of …