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Insects are confronted with the problem of locating food, mates, prey and hosts for their young over long distances, which they often overcome using chemical plume tracking. Tracking a plume of chemical back to its source is made difficult due to the complexity of plume structure. Turbulence and shifts in the wind direction prevail over diffusion in the spreading of an airborne chemical from a point in most cases, producing intricate plumes consisting of filaments of high chemical concentration interspersed with regions of clean air. It has been proposed that insects achieve plume tracking in this environment through variations of anemotaxis, which involves travelling upwind when an attractive chemical is perceived. This study aimed to investigate anemotaxis through the use of a mobile robot to test the efficacy of algorithms which mimic the way insects achieve plume tracking and also to determine whether these algorithms are an effective means of plume tracking for a mobile robot under a range of conditions. To achieve the aims of this study, various plume-tracking algorithms were implemented on a mobile robot built to model a plume-tracking insect and their performance was compared under a range of wind conditions. The algorithms tested were based upon a range of plume-tracking hypotheses. The simplest algorithm was surge anemotaxis, where the robot surged upwind in the presence of an attractive chemical and performed crosswind casting (back and forth motion) in the absence of chemical. The other algorithms tested were the counterturner, where the robot zigzagged upwind, and two bounded search methods. To allow these algorithms to be appropriately implemented, a robot model was constructed that could move in two dimensions and sense the wind velocity and ion level at a point in space. An ion plume was used instead of a chemical plume in each test as it behaves in a similar manner to a chemical plume, but ion sensors have response and recovery times far more rapid than conventional chemical sensors, similar to insects. The plume-tracking robot was tested in three series of tests. Initially, the entire range of plume-tracking algorithms was tested in a wind tunnel with fixed wind direction for a range of wind speeds and release positions. The second series of tests compared the performance of the surge anemotaxis and bounded search algorithms, again in a wind tunnel, but with a wind shift of 20° during some of the tests. The algorithms were tested with and without a direct crosswind surge response to detected wind shifts. The third set of tests examined the performance of the simple and wind shift response algorithms outdoors using natural wind to produce the plume. All algorithms tested achieved successful plume tracking in some conditions. The surge anemotaxis and triangular bounded search algorithms were particularly successful. The tests also showed that the paths obtained from tests undertaken in natural outdoor wind conditions varied greatly from those undertaken in a wind tunnel. This indicates the need to test plume-tracking algorithms in natural environments. This is vital both in the investigation of insect plume-tracking behaviour, as insects navigate in these environments, and in the process of producing plume-tracking robots that are capable of operating effectively in these conditions. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1287973 / Thesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2007

The use of examples in idea generation is a common practice intended to provide inspiration from existing products to the designing of new ones. Examples can be taken from the Internet, engineering textbooks, analogical databases, literature, a company’s prior designs, or from a competitor company, prior work by the designer, and many other sources. These examples are represented in various ways, such as hand sketches, pictures, computer-aided designs (CAD), physical models, activity diagrams, shape grammars, text descriptions, etc. Design representations can also be broken down by function in the form of functional models and decompositions. The use of these visual or physical examples allows engineers to get a clearer picture of how a design or component works and enables them to have a better understanding of the overall design and function. Each representation has inherent advantages and disadvantages in the way that they portray a design. Examples are sources for analogies. Analogies from nature, where biological organisms have solved challenging problems in novel ways, are very useful in engineering idea generation and solution retrieval. This process is called biologically inspired design. Engineers often use biologically inspired design to solve problems while increasing creativity and expanding the solution space. Using this method, engineers are able to learn from nature and apply biological principles to real world engineering problems to make effective designs and produce innovative solutions. It is important to have a clearer understanding of how the use of the representations and characteristics of examples as external stimuli affect the idea generation process in engineering design. Understanding these processes will be invaluable in offering guidelines for how engineering design should be done and what types of external stimuli should be used to allow for innovation and creativity to be enhanced. This dissertation presents four studies that focus on understanding ways that examples can be used to improve the idea generation process. Three of these studies focus on how the representation of externally imposed examples, which may be used as analogues, influences creativity during idea generation while also minimizing design fixation, which occurs when designers adhere to the features of their own initial design solutions or to features of existing examples. The fourth study focuses on the use of examples as sources for analogical mapping and how these examples produce innovative solutions during idea generation. The first study compares CAD, sketch, and photograph representation presented individually. The second study compares CAD and sketch representation presented together, and the third study examines function tree and sketch representations. The fourth study looks at the real-world context and impact of examples used as sources for analogical mapping to inspire innovative solutions. The results of the studies show that CAD representations of good examples are effective in allowing engineers to identify the key working principles of a design and help to develop higher quality design concepts. CAD representations also cause more fixation to the example’s features. Function trees do not cause nor break fixation compared to a control condition, but do reduce fixation compared with sketches. Biological examples can be successfully used as analogues during engineering idea generation to create novel and effective design solutions to relevant and real-world engineering problems.

Biological research over the past several decades has elucidated some of the mechanisms behind highly mobile, efficient, and robust locomotion in insects such as the cockroach. Roboticists have used this information to create biologically-inspired machines capable of running, jumping, and climbing robustly over a variety of terrains. To date, little work has been done to develop an at-scale insect-inspired robot capable of similar feats, due to limitations in fabrication, actuation, and electronics integration at small scales. This thesis addresses these challenges, focusing on the mechanical design and fabrication of a sub-2g walking robot, the Harvard Ambulatory MicroRobot (HAMR). The development of HAMR includes modeling and parameter selection for a two degree of freedom leg powertrain that enables locomotion. In addition, a design inspired by pop-up books that enables fast and repeatable assembly of the miniature walking robot is presented. Finally, a method to drive HAMR resulting in speeds up to 37cm/s is presented, along with simple control schemes. / Engineering and Applied Sciences

In the last decade Support Vector Machines (SVMs) have emerged as an important learning technique for solving classification and regression problems in various fields, most notably in computational biology, finance and text categorization. This is due in part to built-in mechanisms to ensure good generalization which leads to accurate prediction, the use of kernel functions to model non-linear distributions, the ability to train relatively quickly on large data sets using novel mathematical optimization techniques and most significantly the possibility of theoretical analysis using computational learning theory. In this thesis, we discuss the theoretical basis and computational approaches to Support Vector Machines.

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 156-165). Also available in print.

Thesis (Ph.D.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Aug. 19, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Computing Science, University of Alberta." Includes bibliographical references.

abstract: In order for assistive mobile robots to operate in the same environment as humans, they must be able to navigate the same obstacles as humans do. Many elements are required to do this: a powerful controller which can understand the obstacle, and power-dense actuators which will be able to achieve the necessary limb accelerations and output energies. Rapid growth in information technology has made complex controllers, and the devices which run them considerably light and cheap. The energy density of batteries, motors, and engines has not grown nearly as fast. This is problematic because biological systems are more agile, and more efficient than robotic systems. This dissertation introduces design methods which may be used optimize a multiactuator robotic limb's natural dynamics in an effort to reduce energy waste. These energy savings decrease the robot's cost of transport, and the weight of the required fuel storage system. To achieve this, an optimal design method, which allows the specialization of robot geometry, is introduced. In addition to optimal geometry design, a gearing optimization is presented which selects a gear ratio which minimizes the electrical power at the motor while considering the constraints of the motor. Furthermore, an efficient algorithm for the optimization of parallel stiffness elements in the robot is introduced. In addition to the optimal design tools introduced, the KiTy SP robotic limb structure is also presented. Which is a novel hybrid parallel-serial actuation method. This novel leg structure has many desirable attributes such as: three dimensional end-effector positioning, low mobile mass, compact form-factor, and a large workspace. We also show that the KiTy SP structure outperforms the classical, biologically-inspired serial limb structure. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2017

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Continuum robots mimic the principle of a special biological structure known as the muscular hydrostat. These robots have an ability to bend at any location on along its backbone and have potential applications in disaster relief, medical surgeries and nuclear waste disposal. This thesis presents the modeling and verification of a multi-section continuum robot by applying the Cosserat theory of rods. Next, 2D verification is performed on a continuum robot based on a backbone composed of a nickel titanium alloy. In addition, the thesis develops the theoretical foundations for a cable-driven continuum robot by studying the effects of cable guide mass which cause additional deformation of the robot The results of this thesis show that the multi-section model is accurate within 3.4% in predicting the Cartesian tip coordinates, and the model with the cable guides accurate within 1.26% error in predicted versus the observed Cartesian tip coordinates of the backbone.