Foldable and deployable space structures refer to a broad category of pre-fabricated structures that can be transformed from a compact folded configuration to a predetermined expanded configuration. Such deployable structures are stable and can carry loads. These structures are also mechanisms with one degree of freedom in their entire transformation stages whether in the initial folded form or in the final expanded configuration. Usually, pantograph mechanisms or a scissor-like elements (SLEs) are part of such deployable structures. A new analysis tool to study kinematic and static analyses of foldable and deployable space structures /mechanisms, containing SLEs, has been developed in this thesis. The Cartesian coordinates are used to study the kinematics of large deployable structures. For many deployable structures the degree of freedom derived using the standard Grubler-Kutzback criteria, is found to be less than one even though the deployable structure /mechanism can clearly move. In this work the dimension of nullspace of the derivatives of the constraint equations are used to obtain the correct degrees of freedom of deployable structure. A numerical algorithm has been developed to identify the redundant joints /links in the deployable structure /mast which results in the incorrect degrees of freedom obtained by using the Grubler-Kutzback criteria. The effectiveness of the algorithm has been illustrated with several examples consisting of triangular, box shaped SLE mast and an eighteen-sided SLE ring with revolute joints. Further more the constraint Jacobian matrix is also used to evaluate the global degrees of freedom of deployable masts/structures. Closed-form kinematic solutions have been obtained for the triangular and box type masts and finally, as a generalization, extended to a general n-sided SLE based ring structure. The constraint Jacobian matrix based approach has also been extended to obtain the load carrying characteristics of deployable structures with SLEs in terms of deriving the stiffness matrix of the structure. The stiffness matrix has been obtained in the symbolic form and it matches results obtained from other commonly used techniques such as force and displacement methods. It is shown that the approach developed in this thesis is applicable for all types of practical masts with revolute joints where the revolute joint constraints are made to satisfy through the method of Lagrange multipliers and a penalty formulation. To demonstrate the effectiveness of the new method, the procedure is applied to solving (i) a simple hexagonal SLE mast, and (ii) a complex assembly of four hexagonal masts and the results are presented. In summary, a complete analysis tool to study masts with SLEs has been developed. It is shown that the new tool is effective in evaluating the redundant links /joints there by over coming the problems associated with the well –known Grubler-Kutzback criteria. Closed-form kinematic solutions of triangular and box SLE masts as well as a general n-sided SLE ring with revolute joints has been obtained. Finally, the constraint Jacobian based method is used to evaluate the stiffness matrix for the SLE masts. The theory and algorithms presented in this thesis can be extended to masts of different shapes and for the stacked masts.

The heaviest fragments, recoils, have been studied in proton and deuteron induced 28Si reactions and proton-20Ne reactions at 100-300 MeV per nucleon. Inclusive charge and angular distributions and coincidences between He nuclei and recoils have been compared to two theoretical models, Dubna Cascade Model and JAERI Quantum Molecular Dynamics. The overall agreement was good for the reactions with 28Si, however the angular distributions of He fragments could not be reproduced. For the 20Ne reactions the recoil angular distributions were only reproduced for large angles. There was a significant underestimation at small angles and low recoil charge. α-clustering in the bombarding nucleus is a possible explanation for the deviations. In the 100 MeV per nucleon reactions all assumptions of the models may not be valid and the agreement was worst for these reactions. In proton-natXe reactions intermediate mass fragments have been studied from 200 to 1400 MeV. Slow ramping was used to scan the energy. Charge distributions and a caloric curve have been compared to Cascade Fragmentation Evaporation Model. Charge distributions showed good agreement for fragments with Z<8 but the heavier fragments were underestimated.

<p>Numerous studies on mammalian spermatozoa have reported large variations in the dimensions of the main sperm structural components, namely the head, midpiece and flagellum. These variations in sperm architecture are believed to be adaptations for functioning of spermatozoa in complex environments outside the male reproductive system. The midpiece of the mammalian&nbsp / permatozoon contains a varied number of mitochondria, but the reason for the marked difference in the size and structure of this sperm component is not clear. This study&nbsp / confirmed the variations in the sperm morphometry of seven selected mammalian species and revealed unique features of the sperm midpiece and sperm mitochondria of these seven species. Evaluation of several sperm kinematic parameters revealed the unique swimming characteristics of the different spermatozoa. The importance of using standardized motility&nbsp / parameters was highlighted as well as the assessment of different subpopulations of spermatozoa in order to produce more reliable and comparable data. Investigating the role of sperm mitochondria in human sperm&nbsp / metabolism indicated that these organelles are related to sperm function in terms of sperm motility. Furthermore, it was suggested that glycolysis and mitochondrial respiration are linked processes and that both are important for the maintenance of human sperm motility. By optimizing and employing standardized experimental procedures and analysis techniques, this study was&nbsp / able to confirm the species specificity of almost all the sperm parameters evaluated, while also elucidating the phylogenetic relatedness of the non-human primate species. In conclusion, the present study has confirmed that the various midpiece morphometry parameters are related to the remaining sperm morphometry parameters as well as to the sperm kinematic parameters.&nbsp / These proposed associations between the various sperm parameters were used to explain the sperm velocity of two hypothetical and morphologically different sperm structures. Therefore, the results of the current study support the idea of co-evolution between sperm components in mammalian spermatozoa and propose that the midpiece morphometry parameters that are selected for in these spermatozoa are midpiece volume, total number of mitochondrial gyres, thickness of the mitochondrial sheath and mitochondrial height.</p>

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The aim of this study is to obtain optimal position and orientation of a trajectory frame with respect to the fixed frame of the manipulator. The work path which is given in the trajectory frame is also constrained in the workspace of the 3 &ndash / PRS parallel kinematic machine. In the analysis, forward and inverse kinematics solutions are derived as well as the inverse dynamics model using Lagrange&rsquo / s Method. Several algorithms governing the motion of the manipulator are developed. Moreover, optimization goals are defined and evaluated with the genetic algorithm.

As a new pediatric dummy family, the Q-family, is suggested for the European childsafety regulations (R44) and the updated EuroNCAP, it needed to be tested andcompared to the older pediatric dummy family, Hybrid III, used in testing at Autolivtoday.In this study, tests were performed with the Q6 and the Hybrid III 6-year-old. Bothdummies were subjected to eight sled tests using a EuroNCAP acceleration pulse. The sled represented the interior of a Volvo V70, with integrated booster cushions mounted onto the car body through a rigid fixture. Standard belt were used for all tests, except one where pretensioning was used. Static tests investigated how the chest deflection on Q6 was affected by the shoulder belt geometry. Large difference in belt interaction was observed between the dummies. The beltslipped off the Hybrid III’s shoulder for all tests except one, while the belt on the Qdummy’swas hard to provoke off the shoulder. The overall kinematic behavior, beforethe belt slipped off the Hybrid III’s shoulder, were similar for both dummies. Differences in chest deflection on the Q6, depending on the belt geometry, were observed in both the dynamic and the static tests; a shoulder belt geometry closer to theneck resulted in minor displacement than a mid-shoulder belt geometry. After testing, five different damages were observed on the Q6. / Då en ny familj av barnkrockdockor, Q-familjen, är föreslagen för det europeiskalagkravet som reglerar barnsäkerhet (R44), uppstod ett behov av att testa och jämföradessa mot den äldre familjen av barnkrockdockor som används vid testning på Autoliv idag, Hybrid III. I den här studien utfördes tester på Q6 och Hybrid III 6 år. Båda dockorna utsattes föråtta stycken slädtest i en accelerationspuls enligt EuroNCAP. Släden representerade enVolvo V70 med integrerade barnkuddar som monterats i riggen via en stel fixtur. I alla test utom ett användes standardbälten (i undantagsfallet användes försträckare). Statiska tester gjordes för att undersöka hur Q6 påverkades av olika geometrier på axelbältet. Stora skillnader observerades mellan dockornas bältesinteraktion. Bältet gled av HybridIII:s axel i alla test förutom ett, medan det istället var svårt att provocera av bältet från Q-dockans axel. Innan Hybrid III gled ur bältet var dockornas kinematik liknande. I både statiska och dynamiska tester observerades skillnader i bröstintryckning på Q6, beroende på bältesgeometrin; en geometri där axelbältet var placerat nära nackenresulterade i en mindre intryckning än då axelbältet var placerat mitt på axeln. Efte ravslutad testning upptäcktes fem skador på Q6.

Flow of traffic on freeways and limited access highways can be represented as a series of kinemetic waves. Solutions to these systems of equations become problematic under congested traffic flow conditions, and under complicated (real-world) networks. A simplified theory of kinematics waves was previously proposed. Simplifying elements includes translation of the problem to moving coordinate system, adoption of bi-linear speed-density relationships, and adoption of restrictive constraints at the on- and off-ramps. However, these simplifying assumptions preclude application of this technique to most practical situations. This research explores the limitations of the simplified theory of kinematic waves. First this research documents a relaxation of several key constraints. In the original theory, priority was given to on-ramp merging vehicles so that they can bypass any queue at the merge. This research proposes to relax this constraint using a capacity-based weighted fair queuing (CBWFQ) merge model. In the original theory, downstream queue affects upstream traffic as a whole and exiting traffic can always be able to leave as long as it gets to the diverge. This research proposes that this diverge constraint be replaced with a contribution-based weighted splitting (CBWS) diverge model. This research proposes a revised notation system, permitting the solution techniques to be extended to freeway networks with multiple freeways and their ramps. This research proposes a generalization to permit application of the revised theory to general transportation networks. A generalized CBWFQ merge model and a generalized CBWS diverge model are formulated to deal with merging and diverging traffic. Finally, this research presents computational procedure for solving the new system of equations. Comparisons of model predictions with field observations are conducted on GA 400 in Atlanta. Investigations into the performance of the proposed CBWFQ and CBWS models are conducted. Results are quite encouraging, quantitative measures suggest satisfactory accuracy with narrow confidence interval.

Digital Clay is a next generation human-machine communication interface based on a tangible haptic surface. This thesis embraces this revolutionary concept and seeks to give it a physical embodiment that will confirm its feasibility and enable experimentation relating to its utility and possible improvements. Per the approach adopted in work, Digital Clay could be described as a 3D monitor whose pixels can move perpendicularly to the screen to form a morphing surface. Users can view, touch and modify the shape of the working surface formed by these pixels. In reality, the pixels are the tips of micro hydraulic actuators or Hapcel (i.e. haptic cell, since the Digital Clay supports the haptic interface). The user can get a feel of the desired material properties when he/she touches the working surface. The potential applications of Digital Clay cover a wide range from computer aided engineering design to scientific research to medical diagnoses, 3D dynamic mapping and entertainment. One could predict a future in which, by using Digital Clay, not only could the user watch an actor in a movie, but also touch the face of the actor! This research starts from the review of the background of virtual reality. Then the concept and features of the proposed Digital Clay is provided. Research stages and a 5x5 cell array prototype are presented in this thesis on the structural design and control of Digital Clay. The first stage of the research focuses on the design and control of a single cell system of Digital Clay. Control issues of a single cell system constructed using conventional and off-the-shelf components are discussed first in detail followed by experimental results. Then practical designs of micro actuators and sensors are presented. The second stage of the research deals with the cell array system of Digital Clay. Practical structural design and control methods are discussed which are suitable for a 100x 100 (even 1000X 1000) cell array. Conceptual design and detailed implementations are presented. Finally, a 5 x 5 cell array prototype constructed using the discussed design solutions for testing is presented.

KISS (Kinematic Support System) is a locally developed gait analysis system at Middle East Technical University (METU), and the performance of the system was evaluated before as a whole. However, such evaluations do not differentiate between the efficacy of the data acquisition system and the model-based gait analysis methodology. In this thesis, kinematic results of the KISS system will be compared with those of the Ankara University based commercial VICON (Oxford Metrics Ltd., Oxford, UK) system, in view of evaluating the performance of data acquisition system and the gait analysis methodology separately. This study is expected to provide guidelines for future developments on the KISS system.

This work is a comparative study of the various numerical techniques used for analyzing membranes. Membrane analysis is complicated by the fact that local instabilities occur in membranes in the form of small waves or ‘wrinkles’ in zones in which compression tends to appear. This is attributed to their negligible flexural stiffness. Broadly, two approaches exist in the wrinkling analysis of membranes. They are bifurcation analysis and analysis with membrane elements augmented with wrinkling models. In the former approach we can get the wrinkle details while the latter approach gives only the wrinkling zone. The present numerical strategy falls in the category of bifurcation analysis, where we make use of an energy-momentum conserving time integration algorithm in the context of a hybrid element formulation. The solution obtained through this procedure is considered to be accurate, since there are no kinematic assumptions (plane stress, etc.) made in the formulation and we achieve convergence with respect to mesh refinement. We show in this work that the wrinkling process not only depends on the stiffness matrix but also on the transient process. To show this a pseudo-dynamic scheme which is commonly used, is implemented within the hybrid formulation and we show the differences that arise between this scheme and the present method, over some benchmark problems. In this work, we also implement a wrinkling model proposed by Roddeman and finally the advantages and disadvantages of various numerical techniques are discussed.