This thesis studies the in-hand manipulation problem of repositioning finger contacts on an object by controlled sliding. In this thesis we investigate two versions of the problem. First for a multifingered hand with circle patch contacts, we present a framework for planning the motion of the hand to create an...
Stringent demands in the sheet forming industry related to rapid and customized part realization coupled with rigorous requirements on geometric accuracy and product properties have outpaced the capabilities of traditional forming processes. As an emerging novel technology, Double-Sided Incremental Forming (DSIF) offers much higher flexibility with the complete elimination of...
Demands in the aerospace, automotive and biomedical sectors for low-volume sheet metal parts made from materials with high specific strength are growing due to the needs imposed by rapid product development cycles, and personalized products to mention a few. However, high strength-to-weight ratio materials, such as Ti6Al4V, are usually difficult...
Segregation of granular materials with different particle properties (e.g.,~size and density) is a ubiquitous phenomenon in nature and industry. In this thesis, different segregation mechanisms are studied in steady granular heap flows. Flow kinematics and segregation in transient granular flows are also explored. ', '\t', 'First, this thesis studies segregation...
Research on rat whiskers offers knowledge in neuroscience analogous to humans\' sense of touch and inspiration for efficient sensing robotics. The present work investigates the rat whisker system from a mechanical engineering perspective. First, key quasi-static and dynamic properties were quantified in Chapter 2 for individual whiskers in an array,...
Hybrid polymer-peptide conjugates are receiving increasing attention as a promising class of biomaterials. Polymer conjugated coiled-coil peptides are a new addition to these designer macromolecules. Even though a variety of experiments and computational simulations have shown stabilization of helices upon polymer conjugation, there are still many questions regarding the conformations...
The aim of this dissertation is to make sense of nearly a century and a half's worth of observations concerning skin based electroadhesion phenomena. While this is a noble goal in and of itself, further motivation of this work is drawn from fact that the electroadhesive effect is increasingly being...
Greater interest in self-directed professions, like entrepreneurship, have led to a growth in informal workplace communities and social technologies that support new ways of working. However, we have little understanding of how these socio-technical environments support opportunities for professional skill development. The goal of this dissertation is to understand how...
Mechanisms for sensing fluid flow are well studied in arthropods and in some aquatic mammals, but we know very little about how terrestrial mammals detect and localize airflow (Chapter 1). In this thesis, I will describe a series of studies in rodents that investigate the behavioral, mechanical, and neural basis...
Most lubricants contain a series of additives that reduce friction and wear, and protect contacting surfaces. The design of these additives must be modernized to meet the challenges involved with high operating temperatures, extreme environmental conditions, and increasingly stringent environmental regulations. This research demonstrates three novel lubricant additive strategies that...
When granular materials with different properties (size, shape, density, etc.) flow, they tend to segregate. This research addresses a specific form of segregation (axial segregation) that occurs when size bidisperse granular mixtures flow inside a rotating cylindrical tumbler. Axial segregation is the formation of alternating bands of different particle species...
In this presented study, rolling in micro scale level, termed as microrolling, has been advanced and extended its application to surface texturing and roll bonding. Meanwhile, continuous direct current (DC) is introduced to the processes to establish two new microrolling processes: the Electrically-assisted Roll Bonding (EARB) and the Electrically-assisted Microrolling-based...
Intelligent behavior in humans is largely associated with encoding information to discrete symbols. However, symbolic behavior in robotic systems is not widespread, mainly due to lack of tools that constitute symbol-based automation implementable in real time. This thesis proposes real-time algorithms that facilitate and promote symbol-based action and sensing. In...
In recent times, there has been a transition away from traditional engineering materials to more advanced materials that are multi-functional and exhibit improved thermomechanical properties. Much of the inspiration for these advanced materials comes from natural biological systems that fulfill the needs of diverse organisms through clever material organization and...
Predictive modeling has emerged as a new research subject that studies a broad range of modeling techniques to provide confident prediction of the phenomenon of interest by integrating scientific principles together with both computer models and observed physical experiments. Motivated by overcoming the existing challenges, the objective in this dissertation...
This thesis contributes in two ways. First it describes a new framework for the systematic design of collective behaviors and solves a key stability issue under this design framework. In this thesis we apply this framework to solve three tasks in the swarm robotics field: connectivity maintenance, formation control and...
The goal of this dissertation was to elucidate the coalescence of vacancies in the cubic polytype of silicon carbide in a nuclear reactor relevant system. Large-scale empirical potential atomistic simulations were employed and the exploration of long time-scale behavior was performed through a new application of the parallel replica dynamics...
Micro/nanoscale friction behavior has drawn a great deal of attention because it can reveal friction behavior at the interface level and ultimately lead to the discovery of the origin or real mechanism of friction. Surface wettability is an important property of solid surfaces and has been widely used in fundamental...
This thesis deals with three problems encountered in micro- and nano-fluidics: linear stability analysis of electrokinetic mixing in icrochannels, development of a general purpose numerical technique for fully resolved simulation of electrohydrodynamic particulate flows, and studying the phenomenon of molecular scale slip next to boundaries in micro- and nano-channels.
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