Dissertations / Theses: 'Compliant surface'

1

Buckmaster, David J. "Compliant Motion Programming for Robust Robotic Surface Finishing." Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1220637111.

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Willis, G. J. K. "Hydrodynamic stability of boundary layers over compliant surfaces." Thesis, University of Exeter, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377314.

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Pitman, Mark William. "An investigation of flow structure interactions on a finite compliant surface using computational methods." Curtin University of Technology, Department of Mechanical Engineering, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17209.

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A study of the interaction of one-sided flow over a compliant surface is presented. When fluid passes over a flexible surface the simultaneous interaction between the flow and structure gives rise to vibrations and instabilities on the surface as well as in the fluid. The fluid-structure interaction (FSI) has potential to be used in the control of boundary layer dynamics to achieve drag reduction through transition delay. The modelling and control of FSI systems apply to many fields of engineering beyond drag reduction, for example: the modelling and analysis of biomechanical systems; natural environmental systems; aero-elastics; and other areas where flow interacts moving or compliant boundaries. The investigation is performed through numerical simulation. This returns more detail than could be resolved through experiments, while also permitting the study of finite compliant surfaces that are prohibitively difficult, or impossible, to study with analytical techniques. In the present work, novel numerical modelling methods are developed from linear system analysis through to nonlinear disturbances and viscous effects.
Two numerical modelling techniques are adopted to approach the analysis of the FSI system. A potential-flow method is used for the modelling of flows in the limit of infinite Reynolds numbers, while a grid-free Discrete Vortex Method (DVM) is used for the modelling of the rotational boundary-layer flow at moderate Reynolds numbers. In both inviscid and viscous studies, significant contributions are made to the numerical modelling techniques. The application of these methods to the study of flow over compliant panels gives new insight to the nature of the FSI system. In the linear inviscid model, a novel hybrid computational/theoretical method is developed that evaluates the eigenvalues and eigenmodes from a discretised FSI system. The results from the non-linear inviscid model revealed that the steady-state of the non-linear wall motion is independent of initial excitation. For the viscous case, the first application of a DVM to model the interaction of a viscous, rotational flow with a compliant surface is developed. This DVM is successfully applied to model boundary-layer flow over a finite compliant surface.

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Chen, Xiaodong. "Fluid-Structure Interaction Modeling of Epithelial Cell Deformation during Microbubble Flows in Compliant Airways." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1332208862.

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Cuneyitoglu, Ozkul Mine. "Acoustic Perception Through The Ground Interaction Of Compliant Legs Of A Hexapod Robot." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614028/index.pdf.

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A dynamically dexterous legged robot platform generates specific acoustic signals during the interaction with the ground and the environment. These acoustic signals are expected to contain rich information that is related to the interaction surface as a function of the position of the legs and the overall contact process mixed with the actuator sounds that initiate the movement. As the robot platform walks or runs in any environment, this convolved acoustic signal created can be processed and analyzed in real time operation and the interaction surface can be identified. Such an utilization of acoustic data can be possible for various indoor and outdoor surfaces and with this can be useful in adjusting gait parameters that play an essential role in dynamic dexterity. In this work, surface type identification is achieved with using the several popular signal processing and pattern classification methods not on the robot platform but off-line. The performances of the selected features and the algorithms are evaluated for the collected data sets and these outputs are compared with the expectations. Depending on the off-line training and experiment results, the applicability of the study to an embedded robot platform as a future application is found quite feasible and the surface type as an input to the robot sensing is expected to improve the mobility of the robot in both indoor and outdoor environment.

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Jeong, Seung Hee. "Soft Intelligence : Liquids Matter in Compliant Microsystems." Doctoral thesis, Uppsala universitet, Mikrosystemteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-281281.

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Soft matter, here, liquids and polymers, have adaptability to a surrounding geometry. They intrinsically have advantageous characteristics from a mechanical perspective, such as flowing and wetting on surrounding surfaces, giving compliant, conformal and deformable behavior. From the behavior of soft matter for heterogeneous surfaces, compliant structures can be engineered as embedded liquid microstructures or patterned liquid microsystems for emerging compliant microsystems. Recently, skin electronics and soft robotics have been initiated as potential applications that can provide soft interfaces and interactions for a human-machine interface. To meet the design parameters, developing soft material engineering aimed at tuning material properties and smart processing techniques proper to them are to be highly encouraged. As promising candidates, Ga-based liquid alloys and silicone-based elastomers have been widely applied to proof-of-concept compliant structures. In this thesis, the liquid alloy was employed as a soft and stretchable electrical and thermal conductor (resistor), interconnect and filler in an elastomer structure. Printing-based liquid alloy patterning techniques have been developed with a batch-type, parallel processing scheme. As a simple solution, tape transfer masking was combined with a liquid alloy spraying technique, which provides robust processability. Silicone elastomers could be tunable for multi-functional building blocks by liquid or liquid-like soft solid inclusions. The liquid alloy and a polymer additive were introduced to the silicone elastomer by a simple mixing process. Heterogeneous material microstructures in elastomer networks successfully changed mechanical, thermal and surface properties. To realize a compliant microsystem, these ideas have in practice been useful in designing and fabricating soft and stretchable systems. Many different designs of the microsystems have been fabricated with the developed techniques and materials, and successfully evaluated under dynamic conditions. The compliant microsystems work as basic components to build up a whole system with soft materials and a processing technology for our emerging society.

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Hubbard, Neal B. "Dual-stage Thermally Actuated Surface-Micromachined Nanopositioners." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd743.pdf.

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Jensen, Kimberly A. "Analysis and Design of Surface Micromachined Micromanipulators for Out-of-Plane Micropositioning." BYU ScholarsArchive, 2003. https://scholarsarchive.byu.edu/etd/230.

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This thesis introduces two ortho-planar MEMS devices that can be used to position microcomponents: the XZ Micropositioning Mechanism and the XYZ Micromanipulator. The displacement and force relationships are presented. The devices were fabricated using surface micromachining processes and the resulting mechanisms were tested. A compliant XYZ Micromanipulator was also designed to reduce backlash and binding. In addition, several other MEMS positioners were fabricated and tested: the Micropositioning Platform Mechanism (MPM), the Ortho-planar Twisting Micromechanism (OTM), and the Ortho-planar Spring Micromechanism (OSM).

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Wells, Lee Jay. "Advancing Manufacturing Quality Control Capabilities Through The Use Of In-Line High-Density Dimensional Data." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/24865.

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Through recent advancements in high-density dimensional (HDD) measurement technologies, such as 3D laser scanners, data-sets consisting of an almost complete representation of a manufactured part's geometry can now be obtained. While HDD data measurement devices have traditionally been used in reverse engineering application, they are beginning to be applied as in-line measurement devices. Unfortunately, appropriate quality control (QC) techniques have yet to be developed to take full advantage of this new data-rich environment and for the most part rely on extracting discrete key product characteristics (KPCs) for analysis. In order to maximize the potential of HDD measurement technologies requires a new quality paradigm. Specifically, when presented with HDD data, quality should not only be assessed by discrete KPCs but should consider the entire part being produced, anything less results in valuable data being wasted. This dissertation addresses the need for adapting current techniques and developing new approaches for the use of HDD data in manufacturing systems to increase overall quality control (QC) capabilities. Specifically, this research effort focuses on the use of HDD data for 1) Developing a framework for self-correcting compliant assembly systems, 2) Using statistical process control to detect process shifts through part surfaces, and 3) Performing automated part inspection for non-feature based faults. The overarching goal of this research is to identify how HDD data can be used within these three research focus areas to increase QC capabilities while following the principles of the aforementioned new quality paradigm.
Ph. D.

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Merces, Leandro 1989. "Nanomembranas tensionadas : ilhas de InAs em substratos complacentes de Si e microtubos metálicos enrolados como um sensor SERS para monocamadas auto organizadas." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/276952.

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Orientadores: Christoph Friedrich Deneke, Eduardo Granado Monteiro da Silva
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
Made available in DSpace on 2018-08-25T16:50:29Z (GMT). No. of bitstreams: 1 MercesSilva_Leandrodas_M.pdf: 8926273 bytes, checksum: 010f49f410852b0ba0278adfc3e091fa (MD5) Previous issue date: 2014
Resumo: Nanomembranas livres são definidas como filmes ultrafinos constituídos por metais, óxidos ou semicondutores, com espessuras nanométricas e vastas áreas superficiais. São obtidas em geral por um processo de subcorrosão seletiva de uma camada de sacrifício, cujo papel é liberá-las gradualmente, permitindo que o relaxamento da energia elástica nelas armazenada aconteça de maneira controlada, garantindo a integridade final das estruturas. Neste trabalho, nanomembranas livres de Si suportadas por um substrato de SOI foram utilizadas como substratos complacentes para o crescimento de ilhas de InAs em uma câmara de MBE. Além disso, nanomembranas metálicas tensionadas (Ag/Ti/Cr/Ag) foram utilizadas na obtenção de microtubos metálicos enrolados. Análises detalhadas da morfologia das amostras, das estruturas das ilhas e dos microtubos, do strain em ambos os sistemas e de suas possíveis aplicações foram realizadas. A microscopia eletrônica de varredura mostrou que as estruturas permaneceram íntegras após as deformações. A microscopia de força atômica revelou uma baixa densidade de ilhas no topo das nanomembranas de Si. Ademais, possibilitou o aperfeiçoamento de parâmetros superficiais das nanomembranas metálicas e o enrolamento de microtubos com diâmetros pré definidos, garantindo convergência com o modelo analítico. Técnicas de difração de raios X e modelagem por elementos finitos foram utilizadas para elucidar os estados de strain observados em ambas as estruturas. As simulações das curvaturas do substrato complacente de Si e do microtubo metálico sugeriram, respectivamente, um gradiente de strain dependente da posição lateral de cada ilha na nanomembrana e coeficientes de strain constantes nas nanomembranas de Ti e Cr. Finalmente, cálculos envolvendo elasticidade contínua sugeriram que para uma nanomembrana de Si com espessura adequada, o InAs pode transferir strain suficiente para possibilitar o crescimento epitaxial coerente. Ainda, medidas de espectroscopia Raman em moléculas auto organizadas de 1-octadecanethiol, adsorvidas em Ag e aprisionadas entre as paredes dos microtubos metálicos, sugeriram que tal sistema pode ser utilizado como um dispositivo SERS para self-assembled monolayers
Abstract: Freestanding nanomembranes (NMs) are defined as metallic, semiconductor or oxide ultrathin films with nanometer thickness and macroscopic surface areas. In general, they are obtained by a process of selective underetching of a sacrificial layer, whose role is gradually release them, allowing relaxation of their stored elastic energy in a controlled way, ensuring integrity of the final structure. In this work, freestanding edge-supported Si nanomembranes are used as compliant substrate to the InAs growth on a SOI substrate in a MBE chamber. Furthermore, strained metallic nanomembranes (Ag / Ti / Cr / Ag) are used to obtain rolled-up metallic microtubes. A detailed analysis of sample morphology, InAs island and metallic microtube structure, strain on both systems and their possible applications is carried out. Scanning electron microscopy shows the structures stay intact during and after deformation. Atomic force microscopy reveals a lower island density on the top of the freestanding membranes. Moreover, it allowed optimizing the surface parameters of the strained metallic membranes, rolling-up tubes with pre-defined diameters and ensuring convergence with the proposed analytical model. X-ray diffraction and finite element modeling is used to elucidate the observed strain states in both structures. The bending simulations of compliant Si substrate and rolled up metallic microtube suggest, respectively, a lateral strain distribution depending on the island position on the freestanding membrane and a constant strain distribution on the Ti/Cr strained NMs. Finally, continuous elasticity calculations suggest that for a Si nanomembrane with adequate thickness, the InAs can transfer enough strain to enable coherent epitaxial growth. In addition, Raman spectroscopy measurements of 1-octadecanethiol self-assembled molecules adsorbed on an Ag nanomembrane and trapped between the microtube Ag walls suggest the system could be used as a SERS sensor for self-assembled monolayers
Mestrado
Física
Mestre em Física

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11

Huang, Jui-Che. "Boundary layer receptivity of flow over compliant surfaces." Thesis, University of Liverpool, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428289.

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Seereeram, Videsh Ramjas. "Compliant shell mechanisms." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610867.

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Shan, Lei. "Fluid pressure distribution at the interface between compliant and hard surfaces." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/17788.

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Ali, Reza. "Receptivity & transition in boundary layers over rigid and compliant surfaces." Thesis, University of Warwick, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397560.

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15

Cha, Matthew. "Nonlinear Isoviscous Behaviour of Compliant Journal Bearings." Licentiate thesis, KTH, Maskinkonstruktion (Avd.), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91490.

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Plans to shut down nuclear power plants in some European countries as well as increased electricity production by wind and solar power will increase the work load on hydroelectric power plants in the future. Also, due to the power grid regulations, hydroelectric power plants undergo more frequent start-ups and shut-downs. During such transient periods, a large amplitude shaft motion can occur, especially in the power plants with vertical shafts. Large shaft motion is not desirable because it can lead to a machine failure. Furthermore, performance limitations of conventional white metal or babbitted bearings call for the development of new bearing designs. An outstanding tribological performance can be achieved by introducing compliant polymer liners. At the same time, bearings with compliant liners may alter rotor-bearing system dynamic behaviour compared to the systems with conventional white metal bearings. The research approach of this thesis is to employ nonlinear analysis to provide further understanding of the compliant bearing dynamic response to synchronous shaft excitation. Plain cylindrical journal bearings with different compliant liner thicknesses were analysed using a nonlinear approach. The numerical model was verified with an in-house developed code at steady state conditions. Results obtained by the numerical models showed good agreement. After verification of the numerical model for fixed geometry journal bearings, models for tilting pad journal bearings were developed. Results for the tilting pad journal bearing with three pads with line pivot geometry were compared with published data in dynamic conditions. A good agreement was obtained between the two numerical models. The effect of pad pivot geometry on bearing dynamic response was investigated. Vertical and horizontal shaft configurations were compared in terms of the effect of preload factor, pivot offset, tapers and pad inclination angles. Influence of the viscoelastic properties of compliant liners was also studied. All these factors significantly affect bearing dynamic response. It is shown how these factors should be selected to control the journal orbit sizes. It was also shown that the compliant liner provides lower maximum oil film pressure and thicker minimum oil film thickness in the bearing mid-plane in both static and dynamic operating conditions.

QC 20120319

Swedish Hydropower Centre

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Zimmerman, Trent Karl. "A Definition and Demonstration of Developable Mechanisms." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7343.

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There is an increasing need for compact mechanical systems that can accomplish sophisticated tasks. Technologies like ortho-planar and lamina emergent mechanisms (LEMs) have been developed to satisfy needs like these by stowing in planar sheets from which they emerge to perform their function. They can be compact, lightweight, monolithic, scalable, and can withstand harsh environments. They are limited, however, by their base element---planar surfaces. Applications requiring these advantages often include curved surfaces, like aircraft wings, needles, and automotive bodies. In this research, developable mechanisms are presented as a solution to satisfy the need for mechanisms that can conform to or emerge from curved surfaces. Foundational principles which enable designers to leverage the advantages of developable mechanisms are described herein.Developable mechanisms result from the union of mechanisms and developable surfaces. Developable (flattenable) surfaces act as a fitting medium because of their particular advantages in manufacturability and how well they accompany four-link, revolute joint (4R) mechanisms. The definition, including specific qualifying criteria, for developable mechanisms is given. Certain types of mechanisms and classes of developable surfaces can be combined to satisy that criteria. Developable mechanism sub-classes are defined as planar, cylindrical, conical and tangent developable mechanisms. It is shown that planar and spherical mechanisms can be used to create cylindrical and conical developable mechanisms, respectively. The Bennett and other 7R mechanisms can be used for tangent developable mechanisms. Steps for developable mechanism creation are presented, and several physical prototypes are provided to demonstrate feasibility.The cylindrically curved Lamina Emergent Torsional (LET) joint is offered as an enabling technology for producing compliant developable mechanisms. A mathematical model predicting force-deflection and stress behavior is provided and verified. The relationship between stiffness and strain energy storage for curved sheet materials with incorporated LET joints is explored. Material shape factors are used to derive an effective modulus of elasticity and an effective modulus of resilience, which are compared with original values on an Ashby plot. While there is a decrease in the modulus of resilience, there is a much more significant decrease in the modulus of elasticity. A material performance index is provided as an example for determining suitable materials for a given stiffness-reduction application. It is shown that the cylindrically curved LET joint makes it possible to create highly flexible joints that maintain much of their energy storage capability in curved sheet materials.

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Allen, Leanne. "Modelling dolphin hydrodynamics : the numerical analysis and hydrodynamic stability of flow past compliant surfaces." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/844005/.

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Historical numerical methods for solving stiff ordinary differential equations are investigated and a new numerical framework developed and applied to a variety of hydrodynamic stability problems where the effects of passive wall compliance are investigated. The compound matrix method is set in a general coordinate free framework using exterior algebra, and is considered to be the most accurate and easy to implement method for complex systems. The effect of passive wall compliance on the Blasius boundary layer flow is studied. The linear stability of the mean flow state is considered using the new numerical framework and shooting technique. A Newton algorithm is implemented to converge the eigenvalue such that the boundary condition at the surface is satisfied. Curves of neutral stability are produced in the Re-alpha plane for various degrees of compliance, damping and tension parameters. Three dimensionality is incorporated first by a simple introduction of rotation in the flow leading to the investigation of the Ekman boundary layer problem where a Coriolis force instability mechanism (type-2) produces streamwise rolls at modest Reynolds numbers. The linear stability of the Ekman mean flow state is considered using an extension of the new numerical framework for use on the vector space Lambda(3)(C6). Curves of neutral stability are produced in the E-gamma plane for constant values of the Reynolds number and in the Re-gamma plane for a selection of constant angle of orientation, E. This work is extended to consider the effects of wall compliance on the type-2 viscous instability mechanism, with the type-1 mode of instability briefly discussed. Three-dimensionality is then used for a direct application to the dolphin. The stability of the attachment-line boundary layer is investigated on flows past swept wings, relating directly to the dolphins swept-back fins. Wall compliance, modelling the dolphins skin, is included for analysis of its effect on the attachment-line instability.

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Bugg, Samuel R. IV. "Internship with Environmental Quality Management, Inc. - Technical Communication and Environmental Compliance." Miami University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=miami1212758588.

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Kerdok, Amy Elizabeth 1975. "Energetics and mechanics of humans running on surfaces of different compliance." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80600.

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Cheng, Kuang-You B. "Dynamic simulation and optimization of jumping and somersaulting from compliant surfaces : application to springboard standing dives /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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Montalbano, Paul Joseph. "Multistable Shape-Shifting Surfaces (MSSSs)." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4169.

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This paper presents designs for Multistable Shape-Shifting Surfaces (MSSS) by introducing bistability into the Shape-Shifting Surface (SSS). SSSs are defined as surfaces that retain their effectiveness as a physical barrier while undergoing changes in shape. The addition of bistability to the SSS gives the surface multiple distinct positions in which it remains when shifted to, i.e. by designing bistability into a single SSS link, the SSS unit cell can change into multiple shapes, and stabilize within the resulting shape, while maintaining integrity against various forms of external assaults normal to its surface. Planar stable configurations of the unit cell include, expanded, compressed, sheared, half-compressed, and partially-compressed, resulting in the planar shapes of a large square, small square, rhombus, rectangle, and trapezoid respectively. Tiling methods were introduced which gave the ability to produce out-of-plane assemblies using planar MSSS unit cells. A five-walled rigid storage container prototype was produced that allowed for numerous stable positions and volumes. Applications for MSSSs can include size-changing vehicle beds, expandable laptop screens, deformable walls, and volume-changing rigid-storage containers. Analysis of the MSSS was done using pseudo-rigid-Body Models (PRBMs) and Finite Element Analysis (FEA) which ensured bistable characteristics before prototypes were fabricated.

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Perez, Daniel Eduardo. "Shield Design for Maximum Deformation in Shape-Shifting Surfaces." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4561.

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This research presents the initial studies and results on shield design for Shape-Shifting Surfaces (SSSs) seeking maximum compression and maximum expansion of a unit-cell. Shape-Shifting Surfaces (SSSs) are multilayered surfaces that are able to change shape while maintaining their integrity as physical barriers. SSSs are composed of polygonal unit-cells, which can change side lengths and corner angles. These changes are made possible by each side and corner consisting of at least two different shields, or layers of material. As the layers undergo relative motion, the unit-cell changes shape. In order for the SSS to retain its effectiveness as a barrier, no gaps can open between different layers. Also, the layers cannot protrude past the boundaries of the unit-cell. Based on these requirements, using equilateral triangle unit-cells and triangular shields, a design space exploration was performed to determine the maximum deformation range of a unit-cell. It was found that the triangular shield that offered maximum expansion and compression ratio is a right triangle with one angle of 37.5 degrees and its adjacent side equal to 61% of the side of the unit-cell. The key contribution of this paper is a first algorithm for systematic SSS shield design. Possible applications for SSSs include protection, by creating body-armor systems; reconfigurable antennas able to broadcast through different frequencies; recreational uses, and biomedical applications.

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Dalrymple-Hay, Malcolm John Robert. "The relationship between scleroprotein composition, surface tension and compliance in the developing mouse lung." Thesis, Queen Mary, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266227.

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Du, Lucy W. "Design of a constraint device for compliant bodies using quasi-conformal contact surfaces as applied to mouse imaging." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104291.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 99-101).
The purpose of this work is the modeling and prototyping of quasi-conformal constraint contacts and the investigation of their positioning ability for compliant bodies, specifically for the holding of mice in optical imaging setups. The direct application of this work is the restraint of laboratory mice for biological imaging of micron- and submicron-scale biological structures. No existing research has measured the shear stiffness of mouse facial tissue or modeled the effect of quasi-conformal contact constraints on nonlinear materials. The constraint devices and techniques currently available for mice have limitations that have prevented further exploration of their biological structures. The theoretical model, design rationale, and testing results of a prototype device utilizing quasi-conformal constraints are presented in this thesis. This device is capable of restraining anesthetized mice to sub-micron movement in all axes of translation, without additional surgery or discomfort to the mouse. With the findings presented in this thesis, the design of further optimized devices can be made-both for anesthetized and awake mice-enabling further studies in bone marrow and neural activity that are currently impossible. This could ultimately lead to breakthroughs in stem cell and neurobiological research.
by Lucy W. Du.
S.M.

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Lenders, Cyrille. "Etude du comportement mécanique des microbulles. Application à la conception d'une table actionnée pour la micromanipulation en milieu liquide." Phd thesis, Université de Franche-Comté, 2010. http://tel.archives-ouvertes.fr/tel-00527528.

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Cette thèse a pour contexte la micromanipulation en milieu liquide. Cette thématique scientifique vise à comprendre les phénomènes qui interviennent lors de la manipulation dans un liquide de microcomposants, dont la taille peut varier entre 1µm et quelques millimètres. Les travaux de cette thèse se sont focalisés sur l'étude des forces de tension de surface en milieu immergé. L'idée est d'utiliser des bulles de gaz comme un moyen d'actionnement dans les milieux liquides, et nécessite d'étudier les propriétés mécaniques de ces bulles. L'originalité de l'approche repose sur la combinaison de deux effets : la tension de surface et la compressibilité du gaz. La première étape a été l'étude d'un moyen pour générer une unique bulle de gaz de taille voulue. Le contrôle en volume étant une méthode prometteuse, nous avons développé un modèle permettant de prédire la taille d'une bulle, et mis en évidence la possible existence d'une instabilité de la croissance de ces bulles. Une étude analytique adimensionnelle nous a permis de définir un critère pour prédire l'existence de cette instabilité. La seconde étape a porté sur la caractérisation mécanique d'une bulle de gaz en contact avec deux solides. Le modèle implémenté a permis de déduire des propriétés intéressantes des bulles de gaz, notamment une grande compliance dont la valeur peut être contrôlée par des paramètres fluidiques. Un démonstrateur exploitant les bulles de gaz a été conçu : une microtable compliante actionnée par trois bulles. Ces travaux ouvrent la voie vers de nouveaux modes d'actionnement ou de capteur utilisant la transduction entre une énergie fluidique et mécanique opérée par un ménisque capillaire.

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Alfredsson, Bo. "A study on contact fatigue mechanisms." Doctoral thesis, Stockholm, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3028.

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Xiong, Xiaofeng [Verfasser], Florentin [Akademischer Betreuer] Wörgötter, and Ulrich [Akademischer Betreuer] Parlitz. "Adaptive neuromechanical control for energy-efficient and adaptive compliant hexapedal walking on rough surfaces / Xiaofeng Xiong. Gutachter: Florentin Wörgötter ; Ulrich Parlitz. Betreuer: Florentin Wörgötter." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1072550806/34.

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Lenders, Cyrille. "Study of microbubbles mechanical behavior: application to the design of an actuated table for micromanipulation in liquid media." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210089.

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The scope of this thesis is micromanipulation in liquid media. This scientific field aims at understanding the relevant phenomena existing during the manipulation in a liquid of microcomponents having a size between $1,micrometer$ and a few millimeters. This work focuses on the study of surface tension forces in immersed media, because they have favorable scaling effect. The main idea is to use gas bubbles as actuation mean in a liquid, and requires to study the mechanical properties of these bubbles. The originality of the approach is the combination of two effects: surface tension and gas compressibility.

The first step was the study of an efficient mean to generate a single bubble of predefined size. After a detailed review, it appeared that volume controlled bubble generation was a promising method. We have then developed a model to predict the size of a bubble, and emphasized the possible existence of a growing instability. An analytic dimensionless study allowed to define a criterion to predict the existence of this instability.

The second step aimed at the mechanical characterization in quasi static equilibrium of a gas bubble caught between two solids. The purpose is to predict the force generated by the bubble, together with its stiffness. The model implemented allowed to infer interesting properties, notably a high compliance whose value is controllable by fluidic parameters. This compliance property being very important during micromanipulation, a demonstrator making use of gas bubbles has been designed and manufactured. It consists in a compliant microtable actuated by three bubbles. This work opens the way to new actuation or sensing means, using the transduction between fluidic and mechanic energy operated by a capillary bridge.

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Cette thèse a pour contexte la micromanipulation en milieu liquide. Cette thématique scientifique vise à comprendre les phénomènes qui interviennent lors de la manipulation dans un liquide de microcomposants, dont la taille peut varier entre $1,micrometer$ et quelques millimètres. Les travaux de cette thèse se sont focalisés sur l'étude des forces de tension de surface en milieu immergé, car elles bénéficient d'effets d'échelle favorables. L'idée poursuivie est d'utiliser des bulles de gaz comme un moyen d'actionnement dans les milieux liquides, et nécessite d'étudier les propriétés mécaniques de ces bulles. L'originalité de l'approche repose sur la combinaison de deux effets :la tension de surface et la compressibilité du gaz.

La première étape a été l'étude d'un moyen efficace pour générer une unique bulle de gaz de taille voulue. Après une analyse exhaustive, il est apparu que la génération de bulle par le contrôle en volume était une méthode prometteuse. Nous avons alors développé un modèle permettant de prédire la taille d'une bulle, et mis en évidence la possible existence d'une instabilité de la croissance de ces bulles. Une étude analytique adimensionnelle nous a permis de définir un critère pour prédire l'existence ou non de cette instabilité.

La seconde étape a porté sur la caractérisation mécanique en régime quasi statique d'une bulle de gaz en contact avec deux solides. Le but étant de prédire la force générée par une bulle de gaz sur les solides ainsi que sa raideur. Le modèle implémenté a permis de déduire des propriétés intéressantes des bulles de gaz, notamment une grande compliance dont la valeur peut être contrôlée par des paramètres fluidiques. Cette propriété de compliance étant très recherchée en micromanipulation, un démonstrateur exploitant les bulles de gaz a été conçu. Il s'agit d'une microtable compliante actionnée par trois bulles. Ces travaux ouvrent la voie vers de nouveaux modes d'actionnement ou de capteur utilisant la transduction entre une énergie fluidique et mécanique opérée par un ménisque capillaire.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Bretz, David A. "A computer simulation approach to the study of effects of deck surface compliance on initial impact impulse forces in human gait." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA378301.

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Thesis (M.S. in Mechanical Engineering) Naval Postgraduate School, March 2000.
Thesis advisor(s): Kwon, Young W.; McGhee, Robert B. "March 2000." Includes bibliographical references (p. 79-82). Also available online.

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Sadeghipour, Ehsan. "Design and analysis of a magneto-rheological fluid damper with non-linear surfaces to produce effective variable compliance in a robotic transmission." Connect to resource, 2009. http://hdl.handle.net/1811/37153.

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Vieira, Ana Luísa Caldeira. "Influência de situações não conformes devidas à colocação do betãode base em lajes com aplicação de endurecedores de superfície." Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/19041.

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Segundo estudos anteriores, por vezes verificam-se problemas de delaminação e fissuração em pavimentos com a aplicação de endurecedores de superfície, principalmente em condições de vento e/ou calor. Estes fenómenos muitas vezes provêm de outros fatores que não só as condições climatéricas, ou seja, os problemas podem começar no betão de base, associados algumas vezes a situações menos corretas na sua elaboração e aplicação. Por este motivo, nesta dissertação ir-se-á analisar qual a influência do betão de base quando se produz um conjunto de nãoconformidades em obra, nomeadamente ao nível da colocação do betão de base. A partir dos resultados obtidos foi possível verificar que nem todas as situações de nãoconformidade obtiveram maus resultados na ligação endurecedor/betão. /ABSTRATC: According to previous studies, problems with delamination and cracking in pavements with surface hardener have been found, especially in windy conditions and/or heat. But these phenomenons often come from other factors, problems can start at the concrete base, sometimes associated to situations where there is an incorrect design and implementation and for this reason this thesis will analyze the influence of the concrete base when it produces a set of non-conformities in work, particularly in terms of placement of the concrete base. Based on what has been reported by several companies a set of tests has established. From the obtained results it was verified that not all situations of non-compliance showed poor results in the connection of the surface hardener I concrete.

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McHugh, Kathleen M. "Western water law and the stream-aquifer system and how models are used to determine permitting and compliance of rules governing ground and surface water interaction." Thesis, The University of Arizona, 2003. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0234_sip1_w.pdf&type=application/pdf.

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Mauritz, Jakob Martin Andreas. "Homeostasis and volume regulation in the Plasmodium falciparum infected red blood cell." Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/240497.

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The thesis reports on the application of advanced microanalytical techniques to answer a fundamental open question on the homeostasis of Plasmodium falciparum infected red blood cells, namely how infected cells retain their integrity for the duration of the parasite asexual reproduction cycle. The volume and shape changes of infected cells were measured and characterized at femtolitre resolution throughout the intraerythrocytic cycle using confocal microscopy. Fluorescence lifetime imaging and electron probe X-ray microanalysis were applied for the quantification of intracellular haemoglobin and electrolyte concentrations. The cytomechanical properties of uninfected and infected red cells were studied using a novel optical stretcher device, which enabled individual cells to be trapped and manipulated optomechanically in microfluidic channels. Combined, these methods offered a unique insight into the homeostatic and rheological behaviour of malaria-infected red cells. The results were analysed by comparison with predictions from a detailed physiological model of the homeostasis and volume regulation of infected cells, providing broad support to the view that excess haemoglobin consumptions by the parasite was necessary for the integrity of infected cells (the colloidosmotic hypothesis). The dissertation is introduced with an overview of malaria, red blood cells homeostasis and the changes induced by Plasmodium falciparum infection. In the following, this description is extended to an in-depth theoretical analysis of the infected red blood cell homeostasis, from which the need to characterise certain parameters arises. The subsequent chapters address sequentially the assessment of the haemoglobin and electrolyte concentration, cell shape and volume changes and ultimately alterations in cell elasticity. The experimental part is complemented with a comparison of the resulting data to the predictions from the theoretical analysis and an outlook on future work.

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Bonner, J. K. "Kirk", and Silveira Carl de. "Thermal Cycling Fatigue Investigation of Surface Mounted Components with Eutectic Tin-Lead Solder Joints." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611418.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
Eutectic (63% tin-37% lead) or near-eutectic (40% tin-60% lead) tin-lead solder is widely used for creating electrical interconnections between the printed wiring board (PWB) and the components mounted on the board surface. For components mounted directly on the PWB mounting pads, that is, surface mounted components, the tin-lead solder also constitutes the mechanical interconnection. Eutectic solder has a melting point of 183°C (361°F). It is important to realize that its homologous temperature, defined as the temperature in degrees Kelvin over its melting point temperature (T(m)), also in degrees Kelvin, is defined as T/T(m). At room temperature (25°C = 298K), eutectic solder's homologous temperature is 0.65. It is widely acknowledged that materials having a homologous temperature ≥ 0.5 are readily subject to creep, and the solder joints of printed wiring assemblies are routinely exposed to temperatures above room temperature. Hence, solder joints tend to be subject to both thermal fatigue and creep. This can lead to premature failures during service conditions. The geometry, that is, the lead configuration, of the joints can also affect failure. Various geometries are better suited to withstand failure than others. The purpose of this paper is to explore solder joint failures of dual in-line (DIP) integrated circuit components, leadless ceramic chip carriers (LCCCs), and gull wing and J-lead surface mount components mounted on PWBs.

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Pluvinage, Franck. "Effets d’interfaces poroélastiques sur la stabilité d’un écoulement incompressible cisaillé." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2036/document.

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L’objectif de ce travail est d’étendre l’étude locale de la stabilité linéaire des interactions fluide-structure à des domaines peu ou pas encore abordés dans la littérature ; l’influence des interfaces poroélastiques sur les couches limites bidimensionnelles, tridimensionnelles, ou aspirées, ainsi que l’écoulement dans une canopée modélisé par un profil de vitesse réaliste, sont ainsi traités. Les résultats révèlent que dans les couches limites 3D, la compliance réduit le domaine d’instabilité du mode TS dominant mais fait apparaître des modes hydroélastiques ; à l’inverse, la perméabilité stabilise ces derniers tout en déstabilisant l’onde TS, s’apparentant en cela à un amortissement. Sur les ailes en flèche, la transition dépend localement d’instabilités nommées tourbillons Crossflow (CF) d’origine non-visqueuse ; l’effet déstabilisant de la perméabilité sur celles-ci est presque nul tandis que son action positive sur les modes hydroélastiques reste intact, offrant des perspectives prometteuses. Dans le domaine des couches limites aspirées, la quasi-totalité des études publiées reposent sur l’hypothèse d’une perméabilité négligeable et d’une paroi rigide ; or il est démontré ici que la perméabilité (indissociable de la succion) exerce même à faible dose une déstabilisation sur la perturbation dominante et que la compliance (pouvant résulter d’un allègement) provoque l’apparition d’une instabilité absolue. Pour finir, l’attention est portée sur les écoulements dans une canopée -assimilables à des couches de mélange. La stabilité linéaire de l’onde nommée monami ou honami est étudiée sur la base d’un profil de vitesse moyenne réaliste calculé numériquement, puis comparé aux résultats obtenus avec le profil en lignes brisées usuellement employé. L’effet de la force de traînée, communément considéré comme amortissant, se révèle au contraire déstabilisant lorsqu’il est pris en compte dès le calcul du profil de vitesse moyenne
Local linear stability of fluid-structure interactions is investigated in uncustomary fields such as swept, unswept and asymptotic suction incompressible boundary layers developing over compliant, porous plates –in the limit of small permeability– or relatistically-modeled incompressible flows over a canopy. Results show that compliance has a stabilizing effect on the 3D most instable hydrodynamic mode but allows hydroelastic modes to emerge, which take the form of travelling wave flutter instabilities ; conversely, permeability tends to damp the latter ones but to destabilize the former ones. Transition on swept wings also locally depends on 3D unviscid instabilities called Crossflow vortices, hardly unstabilized by permeability ; this provides promizing outlets, since permeability has still a strong positive effect on 3D hydroelastic modes. In the field of incompressible parallel boundary layer flows with uniform suction through the wall, most of the existing studies are based on the assumption that plate’s porosity and flexibility are negligible. Nevertheless, proof is given here that permeability (linked to suction) exerts a strong destabilizing effect on the Tollmien-Schlichting most instable mode. Besides, compliance (that can result from lightering measures) reveals to provoke an absolute instability that is likely to contaminate the entire domain. Finally, attention is paid to incompressible flows across a canopy, that are similar to mixing layers. Linear stability of the coherent motions called monami or honami is adressed using a relatistically-computed velocity profile, then compared to the results obtained with the customary piecewise linear velocity profile. Then, drag force variations are taken into account as soon as velocity profile computing. The result is that drag happens to have a destabilizing effect on the flow, instead of the commonly admitted damping effect

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Ochoa, Hélio José Batista. "Compliant Control of the Kinova Robot for Surface Polishing." Master's thesis, 2018. http://hdl.handle.net/10316/86643.

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Dissertação de Mestrado Integrado em Engenharia Electrotécnica e de Computadores apresentada à Faculdade de Ciências e Tecnologia
O presente trabalho consiste em testar diferentes algoritmos de controlo no robô Kinova JACO² e proporcionar uma solução para o polimento automatizado. Atualmente, o processo de polimento a nível industrial apresenta limitações quer a nível de tempo assim como de produção, uma vez que ainda é realizado manualmente. Devido ao facto deste processo ser moroso e por vezes complexo requer muito tempo por parte do ser humano a desempenhar a mesma tarefa. Inicialmente são testados algoritmos de controlo simplificados por forma a testar e avaliar o desempenho do robô. Os algoritmos testados correspondem a arquiteturas de controlo avançadas, como o controlo de binário computorizado, quer no espaço das juntas quer no espaço de tarefa. Posteriormente é testado o controlador de impedância que permite relacionar uma determinada posição, velocidade e aceleração com a força necessária. Afim de validar os controladores anteriormente mencionados estes são testados em ambiente de simulação assim como em ambiente real. Por fim, o controlador de impedância é testado numa tarefa real de polimento. Verificou-se que o controlador de impedância pode ser usado para desempenhar tarefas de polimento. Contudo, o desempenho do robô necessita melhorias. Os problemas detectados no robô podem estar associados à fricção dos atuadores e a outros fatores externos, o que pode ser mitigado com um estudo minucioso dos vários parâmetros considerados no controlador e dos vários parâmetros internos associados ao manipulador robótico.
This work consists in testing different control algorithms in the Kinova JACO² robot and providing a solution for automated polishing processes. Nowadays, the polishing process at industrial level presents limitations both at the level of time and production capacity, since it is performed manually. Due to the fact that this process is time-consuming and sometimes complex it requires a lot of time on the part of the human being to perform the same task. Initially, several simplified control algorithms are tested so as to evaluate the robot performance. The tested algorithms correspond to advanced control architectures, such as computed torque controller in the joint space and in the task space. Then, the impedance controller is tested since it allows to regulate the relationship between the required force and position, velocity and acceleration of the robot manipulator. In order to validate the mentioned controllers they are tested in simulated environment as well as in real environment. Finally, the impedance controller is tested in a real surface polishing task. In conclusion, the impedance controller can be used to perform polishing tasks. However, the robot performance need improvements. The problems detected in the manipulator can be associated with the friction of the actuators and other external factors, which can be mitigated by an in-depth study of the several parameters considered in the controller and the various internal parameters associated with the manipulator arm.

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Scharf, Ingolf, Markus Müller, Dominik Höhlich, Thomas Mehner, Ulrich Holländer, Hans Jürgen Maier, and Thomas Lampke. "Cost-efficient and reach-compliant surface treatment of bipolar plates." 2019. https://monarch.qucosa.de/id/qucosa%3A36249.

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In fuel cells, stacks of several hundred bipolar plates are combined in membrane electrode assemblies, in which the electrochemical reactions take place. As a result, it must be possible to produce the bipolar plates cost-efficiently. In addition, the corrosion resistance in the surrounding medium and the electrical conductivity have to be sufficiently high. As stainless steels show passivation over time, more expensive materials, like graphite or noble-metal coatings, are used. This paper describes an alternative coating, which can fulfil the above-mentioned requirements. Using electroplating, Cr coatings with thicknesses > 20 µm can be deposited at low costs and REACH compliant. Subsequently, the Cr layers are gas nitrided resulting in a dense Cr-N coating with electrical and corrosion properties exceeding the ones of common stainless steels. Using this new approach, well-performing fuel cells could be produced cost-efficiently.

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Huang, Jo-Tung, and 黃科棟. "Slope Surface Compliant Motion Control Design of a Walking Help Robot." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/73348429130195253897.

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碩士
國立交通大學
電控工程研究所
98
In this thesis, an omni-directional walking help robot (Walbot) is presented for assisting elderly or handicapped people in indoor walking. A compliant motion controller with gravity compensation has been designed to make this powered robotic walker with passive behavior on a slope surface. This design allows a user to handle the robot safely to follow his/her motion intent. In order to detect user's motion intent, an external-force observer has been developed to replace expensive force/torque sensors. On a slope surface, the gravity force will affect robot's dynamic motion and contradict to the user's motion intent. A gravity compensator is proposed and added to the compliant motion control loop. Then, the user can walk with the robot on the slope as if it is on a flat surface. The proposed control method has been validated by experimental results.

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何建賢. "Application of the robot compliant motion moving along an irregular surface." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/99386853695561108905.

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碩士
國立中央大學
機械工程研究所
87
The objective of this thesis is the application of the force sensor to meet robot trajectory design. Force feedback signal getting from a force sensor is easier and more exact than that getting by computing Jacobian matrix, which is learned in robotics. We controlled the robot end-effector moving along irregular surface with a constant contact force. The experiment study is the primary focus of this thesis. At first, we use a personal computer instead of the controller and driver of SCORBOT-ER VII robot applied by the robot producer. And then, we use a 2020 decoder circuit to decode the angle signal from encoder. Using force sensor to get force feedback signal we can control the end-effector of the robot to touch object in a constant force. The controller of the system is a digital controller including a PC, A/D converter, D/A converter, and the current amplifier. By solving inverse manipulator kinematic equations we can get the data of joint angle ( ) vs. time ( ) that are the reference signals of the system. Finally, we design a suitable PID controller to the system, and let the robot arms tracking the reference angle signals that we have computed. And then, the end-effector of the robot can follow the trajectory that we desired.

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Fletcher, Alex J. P. "The use of compliant surface for supersonic flow over a compression ramp /." Diss., 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3073973.

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Chang, Ji-Hone, and 張吉宏. "Precision Mill-Polishing Processes for Blend Surface -Application and Analysis by Compliant Tool Device." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/68742797001773737595.

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碩士
國立臺灣海洋大學
機械與輪機工程學系
93
Abstract The purpose of this thesis is to study and to design a three-axis compliance cutting tool system for cutting kind of the miniature plane or curved surface. Ranged from 0.001mm to 0.01mm . the compliance cutting tool structure was designed using feature of the fault. Then the finite element method was used to analyze the deformation. Finally it by ABS material a rapid prototyping method to make for an integral decrease interstices. Piezoelectricity actuate to push cutting tool with meter movement, such as the micro displacement were 40 μm、45μm、31μm in X、Y、Z axle respectively. But piezoelectricity material and ABS material have hysteresis movement phenomenon. To compensate method was the error utility caused by the hysteresis movement radial basis function network. The experimental results show the error in X、Y、Z axle can be compensated as small as 1.85μm、0.92μm and 2.4μm respectively. For verifying the correctness of tool system, a parabolic curve was schemed. Then the cutting tool path was planned and actuated according to the relationship of actuated voltage and displacement. The measured results showed that the maximum error is less than 1.4μm. That error range is adequate for the study.

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"Anticipatory Muscle Responses for Transitioning Between Rigid Surface and Surfaces of Different Compliance: Towards Smart Ankle-foot Prostheses." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.53887.

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abstract: Locomotion is of prime importance in enabling human beings to effectively respond in space and time to meet different needs. Approximately 2 million Americans live with an amputation with most of those amputations being of the lower limbs. To advance current state-of-the-art lower limb prosthetic devices, it is necessary to adapt performance at a level of intelligence seen in human walking. As such, this thesis focuses on the mechanisms involved during human walking, while transitioning from rigid to compliant surfaces such as from pavement to sand, grass or granular media. Utilizing a unique tool, the Variable Stiffness Treadmill (VST), as the platform for human walking, rigid to compliant surface transitions are simulated. The analysis of muscular activation during the transition from rigid to different compliant surfaces reveals specific anticipatory muscle activation that precedes stepping on a compliant surface. There is also an indication of varying responses for different surface stiffness levels. This response is observed across subjects. Results obtained are novel and useful in establishing a framework for implementing control algorithm parameters to improve powered ankle prosthesis. With this, it is possible for the prosthesis to adapt to a new surface and therefore resulting in a more robust smart powered lower limb prosthesis.
Dissertation/Thesis
Masters Thesis Biomedical Engineering 2019

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43

王珮穎. "A Statistical Elliptic Microcontact Model Considering Elastic, Elastoplastic and Plastic Deformation and Its Applications to NonGaussion Surface Height Distributions and Compliant Electrical Connectors." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/68678369356914719494.

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Price, Mark. "A Haptic Surface Robot Interface for Large-Format Touchscreen Displays." 2016. https://scholarworks.umass.edu/masters_theses_2/371.

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This thesis presents the design for a novel haptic interface for large-format touchscreens. Techniques such as electrovibration, ultrasonic vibration, and external braked devices have been developed by other researchers to deliver haptic feedback to touchscreen users. However, these methods do not address the need for spatial constraints that only restrict user motion in the direction of the constraint. This technology gap contributes to the lack of haptic technology available for touchscreen-based upper-limb rehabilitation, despite the prevalent use of haptics in other forms of robotic rehabilitation. The goal of this thesis is to display kinesthetic haptic constraints to the touchscreen user in the form of boundaries and paths, which assist or challenge the user in interacting with the touchscreen. The presented prototype accomplishes this by steering a single wheel in contact with the display while remaining driven by the user. It employs a novel embedded force sensor, which it uses to measure the interaction force between the user and the touchscreen. The haptic response of the device is controlled using this force data to characterize user intent. The prototype can operate in a simulated free mode as well as simulate rigid and compliant obstacles and path constraints. A data architecture has been created to allow the prototype to be used as a peripheral add-on device which reacts to haptic environments created and modified on the touchscreen. The long-term goal of this work is to create a haptic system that enables a touchscreen-based rehabilitation platform for people with upper limb impairments.

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"Simulation and Analysis of Walking on Compliant Surfaces." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.53644.

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abstract: There are a large group of amputees living in the country and the number of them is supposed to increase a lot in the following years. Among them, lower-limb amputees are the majority. In order to improve the locomotion of lower-limb amputees, many prostheses have been developed. Most commercially available prostheses are passive. They can not actively provide pure torque as an intact human could do. Powered prostheses have been the focus during the past decades. Some advanced prostheses have been successful in walking on level ground as well as on inclined surface and climbing stairs. However, not much work has been done regarding walking on compliant surfaces. My preliminary studies on myoelectric signals of the lower limbs during walking showed that there exists difference in muscle activation when walking on compliant surfaces. However, the mapping of muscle activities to joint torques for a prosthesis that will be capable of providing the required control to walk on compliant surfaces is not straightforward. In order to explore the effects of surface compliance on leg joint torque, a dynamic model of the lower limb was built using Simscape. The simulated walker (android) was commanded to track the same kinematics data of intact human walking on solid surface. Multiple simulations were done while varying ground stiffness in order to see how the torque at the leg joints would change as a function of the ground compliance. The results of this study could be used for the control of powered prostheses for robust walking on compliant surfaces.
Dissertation/Thesis
Masters Thesis Aerospace Engineering 2019

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46

Xiong, Xiaofeng. "Adaptive neuromechanical control for energy-efficient and adaptive compliant hexapedal walking on rough surfaces." Doctoral thesis, 2015. http://hdl.handle.net/11858/00-1735-0000-0022-6019-B.

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Tseng, Po-Han, and 曾柏翰. "Application of Compliance Mechanism in the Grinding and Polishing of Semispherical Surfaces." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/hsb2t3.

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碩士
國立臺北科技大學
製造科技研究所
98
The purpose of this paper is to investigate the effects of different spring rate on the machine surface roughness and contour roundness by using an compliance mechanism attached to the grinding or polishing tools. In this study, the material used is NAK80 die tool steel. The CAD/CAM software is used to plan the reciprocate tool path for milling, grinding, lapping and polishing. The spiral path is used to create the cutting tool path for machining the mold with a concave hemisphere surface. The experimental study including grinding, lapping and polishing with four combinations of spring rate are performed on the five axis machining center. The surface roughness and roundness of machined components are measured by using measuring instruments. The experimental results show that surface roughness can be reduced by imposing compliance in the tool holder on CNC machining, the surface roughness is reduced from 1.290 μm to 0.695 μm, and the roundness is from 0.031 mm to 0.012 mm.

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戴于晸. "Optimized Design and Research on Curved Surface Reflector Core in Compliance with the European ECE Regulation." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2fr8x4.

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碩士
國立高雄應用科技大學
電機工程系博碩士班
107
The thesis is mainly to design the curved and micro-prism reflectors for the cars that will be produced in large quantities in the future to enter the international market. The specifications in the global car market are mainly divided into specifications of E/e-Mark (from ECE) and SAE International; however, the general reflectors with the function of directly reflecting direct light cannot meet the specifications of E/e-Mark (from ECE) and SAE International. Adopting the structure of the planar and micro-prism reflector and stimulating its operating principles, this study discusses the relationship between the structure of the reflector and the change of the light reflection. Then it modifies the planar and micro-prism reflector into the curved micro-prism reflector, and finally conducts the optical simulation with TracePro to maximize its effective range as well as to meet the regulations on the observation angle and the coefficients of the retro-reflection by ECE

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Trajtman, Adriana. "Evaluation of improved housekeeping compliance and the use of microfibre cleaning cloths on reducing environmental reservoirs of antibiotic resistant organisms and Clostridium difficile in health care facilities." 2010. http://hdl.handle.net/1993/3912.

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Contaminated environmental surfaces can be a means of transmission of Clostridium difficile spores in health-care facilities. The study objectives are to assess the value of the UV marker as an audit tool for improving housekeeping compliance and to compare microfiber and cotton cloths for removal of Clostridium difficile spores from surfaces. A lotion visible only under short-wave UV light (UV Marker) was applied to different surfaces within the patient’s washrooms on consecutive week days, over a twenty-four week period. The Study included three Arms: Arm one received feedback for 24 weeks , Arm two received feedback for the first 12 weeks and Arm three was given feedback for the last 12 weeks based on UV Marker results. The visual audit resulted in a cleaning compliance of 55%; whereas, feedback with the UV Marker led to a housekeeping compliance of 90%. The UV marker is a better audit tool than visual inspection for improving cleaning compliance of housekeeping staff. The use of microfiber cloths may enhance efficiency of microbial removal during surface cleaning.

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50

Sakib, Nazmus. "Response of asphalt matrix under multi-axial stress state." Thesis, 2014. http://hdl.handle.net/2152/25860.

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Abstract:

The pavement system is subjected to complex stress states under vehicular loading. A combination of axial and shear stress has been identified as a potential cause of top down cracking (or more precisely near surface cracking) in asphalt surface. Therefore, in terms of modeling the material response a pertinent question is whether the typical one-dimensional viscoelastic properties of the material are affected by a multi-axial stress state. Such changes are referred to as interaction non-linearity. The objective of this study was to evaluate whether or not asphalt composites are susceptible to such interaction effects. The study was conducted using fine aggregate matrix (FAM), which comprises graded sand and asphalt binder. To provide multi-modal loading, the rectangular prismatic FAM specimens were used with the Arcan apparatus. This apparatus ensures low bending stress and offers adjustments in the setup to provide different proportions of axial and shear stress. Finite element modeling was done to evaluate the stress state for different orientations of the sample in the Arcan apparatus. For measurement of strain, the study used digital image correlation (DIC), which is an optical, non-contact measurement technology. The strain thus measured was used to compute shear compliance. Fitting parameters of the shear compliances were estimated for power-law and Prony series for different loading orientations. When compared, the measured shear compliances do not show perceivable variation with respect to different proportion of axial stress applied in conjunction. However, further testing with different temperatures and other magnitudes of shear stress is necessary. This study is the first step to allow modeling of stress and crack propagation behavior near the pavement surface where complex stress state is present.
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Dissertations / Theses on the topic 'Compliant surface'

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