How youth learn through creating physical computer interfaces

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.Includes bibliographical references (p. 129-130).The Hook-ups project introduces a new set of tools, materials, and activities intended to support children in creating physical computer input devices for computer programs they write. This project introduces a new approach to learning-through-design by providing opportunities for children to engage in both physical and computational design concurrently. This thesis describes the design of Hook-ups tools and materials, including the development of Scratch Patches - a new puzzle-piece-like set of technological building blocks used to build computer input devices. Also presented are classifications of the types of Hook-ups developed by youth, an analysis of what and how youth learned through Hook-ups design activities, and a roadmap for future work in the area of interaction design for children.by Amon Daran Millner.S.M

Functional and developmental characterization of local motion sensing neurons in the fly visual system

Sighted animals use visual motion information to navigate in their environment, to search for food sources or mating partners and to avoid potentials predators. However, directional motion information is not explicitly represented in the photoreceptor signals, but rather needs to be extracted by postsynaptic circuits. For such a motion computation, different algorithmic models were proposed. The most prominent model multiplies the signal of two neighboring photoreceptors after one of them was temporally delayed. Fruit flies are well suited as a model organism to study the neuronal mechanisms underlying motion perception. With a low spatial but high temporal visual resolution, fruit flies are able to detect many different kinds of motion stimuli and perform a wide range of visually evoked behaviors. Thanks to the multitude of genetic tools optimized for Drosophila melanogaster, detailed manipulation of neuronal function can be performed on a molecular as well as on a cellular level. These tools allow to dissect the components of a neuronal circuit and investigate their respective function. In the visual system of flies exist neurons sensitive to wide field motion, which are important for the course control of flies. An open question remains the computation of upstream neurons detecting local motion. During my doctoral work I studied various aspects of the local motion sensing cells in the fly visual system: their functional properties, their importance for different behavioral tasks as well as their differentiation during development. In the first manuscript included in this thesis, we demonstrated that T4 and T5 cells are the elementary local motion sensing neurons of the fly. Calcium activity imaging of T4 and T5 cells revealed that four subtypes exist, each sensitive to motion along one of the four cardinal directions. Moreover, T4 cells responded specifically to light increments and T5 cells to light decrements. Blocking T4 neurons abolished the ON motion responses of postsynaptic lobula plate tangential cells. Accordingly, inactivating T5 cells inhibited the reaction of lobula plate tangential cells to OFF motion. We confirmed this effect by examining the turning behavior of walking flies with either T4 or T5 cells blocked. Flies without T4 output responded only to OFF edge motion, while flies with blocked T5 cells responded exclusively to ON edge motion. To investigate the functional role of the local motion sensing T4 and T5 cells, we studied the consequences of blocking these neurons and tested visual behavior. In the second manuscript, we described that inactivating T4 and T5 cells abolished the optomotor turning response of the flies. However, the motion blind flies were still able to orient towards a dark, vertical bar. Wedemonstrated that flies respond to the position of a bar independent of a motion cue. Therefore, we concluded that flies use positional as well as motion information to orient towards an attractive object. In the third manuscript, we further investigated the role of T4 and T5 cells in flight behavior and found these cells involved in the detection of expansion motion. Flight avoidance turns as well as landing responses of flies depend on functional T4 and T5 cells. These behaviors are evoked by expansion motion like a looming stimulus, which mimics an approaching predator or object. The importance of T4 and T5 cells for looming evoked behavior suggests, that these cells are not only connected to lobula plate tangential cells, which respond to rotatory wide-field motion, but are also presynaptic to looming sensitive neurons in the lobula plate. The last manuscript describes transcription factors important for the differentiation of T4 and T5 neurons. The morphology of all T4 and T5 subtypes is comparable; their dendrites are oriented opposite to the preferred direction of the cell and the axon terminals target one of the four lobula plate layers. Both the dendrites and the axon terminals are limited to only one layer of their respective neuropil. We found two postmitotic transcription factors expressed in the young T4 and T5 cells, SoxN and Sox102F, which regulate the common features of all subtypes. These transcription factors are crucial for the proper morphology of the T4 and T5 cells, as well as the function of the adult neurons

Functional and developmental characterization of local motion sensing neurons in the fly visual system

Sighted animals use visual motion information to navigate in their environment, to search for food sources or mating partners and to avoid potentials predators. However, directional motion information is not explicitly represented in the photoreceptor signals, but rather needs to be extracted by postsynaptic circuits. For such a motion computation, different algorithmic models were proposed. The most prominent model multiplies the signal of two neighboring photoreceptors after one of them was temporally delayed. Fruit flies are well suited as a model organism to study the neuronal mechanisms underlying motion perception. With a low spatial but high temporal visual resolution, fruit flies are able to detect many different kinds of motion stimuli and perform a wide range of visually evoked behaviors. Thanks to the multitude of genetic tools optimized for Drosophila melanogaster, detailed manipulation of neuronal function can be performed on a molecular as well as on a cellular level. These tools allow to dissect the components of a neuronal circuit and investigate their respective function. In the visual system of flies exist neurons sensitive to wide field motion, which are important for the course control of flies. An open question remains the computation of upstream neurons detecting local motion. During my doctoral work I studied various aspects of the local motion sensing cells in the fly visual system: their functional properties, their importance for different behavioral tasks as well as their differentiation during development. In the first manuscript included in this thesis, we demonstrated that T4 and T5 cells are the elementary local motion sensing neurons of the fly. Calcium activity imaging of T4 and T5 cells revealed that four subtypes exist, each sensitive to motion along one of the four cardinal directions. Moreover, T4 cells responded specifically to light increments and T5 cells to light decrements. Blocking T4 neurons abolished the ON motion responses of postsynaptic lobula plate tangential cells. Accordingly, inactivating T5 cells inhibited the reaction of lobula plate tangential cells to OFF motion. We confirmed this effect by examining the turning behavior of walking flies with either T4 or T5 cells blocked. Flies without T4 output responded only to OFF edge motion, while flies with blocked T5 cells responded exclusively to ON edge motion. To investigate the functional role of the local motion sensing T4 and T5 cells, we studied the consequences of blocking these neurons and tested visual behavior. In the second manuscript, we described that inactivating T4 and T5 cells abolished the optomotor turning response of the flies. However, the motion blind flies were still able to orient towards a dark, vertical bar. Wedemonstrated that flies respond to the position of a bar independent of a motion cue. Therefore, we concluded that flies use positional as well as motion information to orient towards an attractive object. In the third manuscript, we further investigated the role of T4 and T5 cells in flight behavior and found these cells involved in the detection of expansion motion. Flight avoidance turns as well as landing responses of flies depend on functional T4 and T5 cells. These behaviors are evoked by expansion motion like a looming stimulus, which mimics an approaching predator or object. The importance of T4 and T5 cells for looming evoked behavior suggests, that these cells are not only connected to lobula plate tangential cells, which respond to rotatory wide-field motion, but are also presynaptic to looming sensitive neurons in the lobula plate. The last manuscript describes transcription factors important for the differentiation of T4 and T5 neurons. The morphology of all T4 and T5 subtypes is comparable; their dendrites are oriented opposite to the preferred direction of the cell and the axon terminals target one of the four lobula plate layers. Both the dendrites and the axon terminals are limited to only one layer of their respective neuropil. We found two postmitotic transcription factors expressed in the young T4 and T5 cells, SoxN and Sox102F, which regulate the common features of all subtypes. These transcription factors are crucial for the proper morphology of the T4 and T5 cells, as well as the function of the adult neurons

Large space structures and systems in the space station era: A bibliography with indexes (supplement 04)

Bibliographies and abstracts are listed for 1211 reports, articles, and other documents introduced into the NASA scientific and technical information system between 1 Jul. and 30 Dec. 1991. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

Models, algorithms and architectures for cooperative manipulation with aerial and ground robots

Les dernières années ont vu le développement de recherches portant sur l'interaction physique entre les robots aériens et leur environnement, accompagné de l'apparition de nombreux nouveaux systèmes mécaniques et approches de régulation. La communauté centrée autour de la robotique aérienne observe actuellement un déplacement de paradigmes des approches classiques de guidage, de navigation et de régulation vers des tâches moins triviales, telle le développement de l'interaction physique entre robots aériens et leur environnement. Ceci correspond à une extension des tâches dites de manipulation, du sol vers les airs. Cette thèse contribue au domaine de la manipulation aérienne en proposant un nouveau concept appelé MAGMaS, pour " Multiple Aerial Ground Manipulator System ". Les motivations qui ont conduites à l'association de manipulateurs terrestres et aériens pour effectuer des tâches de manipulation coopérative, résident dans une volonté d'exploiter leurs particularités respectives. Les manipulateurs terrestres apportant leur importante force et les manipulateurs aériens apportant leur vaste espace de travail. La première contribution de cette thèse présente une modélisation rigoureuse des MAGMaS. Les propriétés du système ainsi que ses possibles extensions sont discutées. Les méthodes de planning, d'estimation et de régulation nécessaire à l'exploitation des MAGMaS pour des tâches de manipulation collaborative sont dérivées. Ce travail propose d'exploiter les redondances des MAGMaS grâce à un algorithme optimal d'allocation de forces entre les manipulateurs. De plus, une méthode générale d'estimation de forces pour robots aériens est introduite. Toutes les techniques et les algorithmes présentés dans cette thèse sont intégrés dans une architecture globale, utilisée à la fois pour la simulation et la validation expérimentale. Cette architecture est en outre augmentée par l'addition d'une structure de télé-présence, afin de permettre l'opération à distances des MAGMaS. L'architecture générale est validée par une démonstration de levage de barre, qui est une application représentative des potentiels usages des MAGMaS. Une autre contribution relative au développement des MAGMaS consiste en une étude exploratoire de la flexibilité dans les objets manipulés par un MAGMaS. Un modèle du phénomène vibratoire est dérivé afin de mettre en exergue ses propriétés en termes de contrôle. La dernière contribution de cette thèse consiste en une étude exploratoire sur l'usage des actionneurs à raideur variable dans les robots aériens, dotant ces systèmes d'une compliance mécanique intrinsèque et de capacité de stockage d'énergie. Les fondements théoriques sont associés à la synthèse d'un contrôleur non-linéaire. L'approche proposée est validée par le biais d'expériences reposant sur l'intégration d'un actionneur à raideur variable léger sur un robot aérien.In recent years, the subject of physical interaction for aerial robots has been a popular research area with many new mechanical designs and control approaches being proposed. The aerial robotics community is currently observing a paradigm shift from classic guidance, navigation, and control tasks towards more unusual tasks, for example requesting aerial robots to physically interact with the environment, thus extending the manipulation task from the ground into the air. This thesis contributes to the field of aerial manipulation by proposing a novel concept known has Multiple Aerial-Ground Manipulator System or MAGMaS, including what appears to be the first experimental demonstration of a MAGMaS and opening a new route of research. The motivation behind associating ground and aerial robots for cooperative manipulation is to leverage their respective particularities, ground robots bring strength while aerial robots widen the workspace of the system. The first contribution of this work introduces a meticulous system model for MAGMaS. The system model's properties and potential extensions are discussed in this work. The planning, estimation and control methods which are necessary to exploit MAGMaS in a cooperative manipulation tasks are derived. This works proposes an optimal control allocation scheme to exploit the MAGMaS redundancies and a general model-based force estimation method is presented. All of the proposed techniques reported in this thesis are integrated in a global architecture used for simulations and experimental validation. This architecture is extended by the addition of a tele-presence framework to allow remote operations of MAGMaS. The global architecture is validated by robust demonstrations of bar lifting, an application that gives an outlook of the prospective use of the proposed concept of MAGMaS. Another contribution in the development of MAGMaS consists of an exploratory study on the flexibility of manipulated loads. A vibration model is derived and exploited to showcase vibration properties in terms of control. The last contribution of this thesis consists of an exploratory study on the use of elastic joints in aerial robots, endowing these systems with mechanical compliance and energy storage capabilities. Theoretical groundings are associated with a nonlinear controller synthesis. The proposed approach is validated by experimental work which relies on the integration of a lightweight variable stiffness actuator on an aerial robot

Compilation of thesis abstracts, December 2006

NPS Class of December 2006This quarter’s Compilation of Abstracts summarizes cutting-edge, security-related research conducted by NPS students and presented as theses, dissertations, and capstone reports. Each expands knowledge in its field.http://archive.org/details/compilationofsis109452750

Waterborne Autonomous Vehicle

This project designed and realized the Waterborne Autonomous VEhicle (WAVE), a submersible modular robotic platform to enable research on underwater technologies at WPI at minimal cost. WAVEÂ’s primary design objectives were modularity and expandability while adhering to the regulations for the international competition held by the Association for Underwater Vehicle Systems International. WAVEÂ’s core features include a six degree-of-freedom chassis, a modular electronic infrastructure, and an easily configurable software framework