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We present a framework for the design and implementation of visually-guided, interactive, mobile robots. Essential to the framework's robust performance is our behavior-based robot control architecture enhanced with a state of the art decision-theoretic planner that takes into account the temporal characteristics of robot actions and allows us to achieve principled coordination of complex subtasks implemented as robot behaviors/skills. We study two different models of the decision theoretic layer: Multiply Sectioned Markov Decision Processes (MSMDPs) under the assumption that the world state is fully observable by the agent, and Partially Observable Markov Decision Processes (POMDPs) that remove the latter assumption and allow us to model the uncertainty in sensor measurements. The MSMDP model utilizes a divide-and-conquer approach for solving problems with millions of states using concurrent actions. For solving large POMDPs, we present heuristics that improve the computational efficiency of the point-based value iteration algorithm while tackling the problem of multi-step actions using Dynamic Bayesian Networks. In addition, we describe a state-of-the-art simultaneous localization and mapping algorithm for robots equipped with stereo vision. We first present the Monte-Carlo algorithm sigmaMCL for robot localization in 3D using natural landmarks identified by their appearance in images. Secondly, we extend sigmaMCL and develop the sigmaSLAM algorithm for solving the simultaneous localization and mapping problem for visually-guided, mobile robots. We demonstrate our real-time algorithm mapping large, indoor environments in the presence of large changes in illumination, image blurring and dynamic objects. Finally, we demonstrate empirically the applicability of our framework for developing interactive, mobile robots capable of completing complex tasks with the aid of a human companion. We present an award winning robot waiter for serving hors d'oeuvres at receptions and a robot for delivering verbal messages among inhabitants of an office-like environment. / Science, Faculty of / Computer Science, Department of / Graduate

Pre-visualisation is an important tool for planning films during the pre-production phase of filmmaking. Existing pre-visualisation authoring tools do not effectively support the user in authoring pre-visualisations without impairing software usability. These tools require the user to either have programming skills, be experienced in modelling and animation, or use drag-and-drop style interfaces. These interaction methods do not intuitively fit with pre-production activities such as floor planning and storyboarding, and existing tools that apply a storyboarding metaphor do not automatically interpret user sketches. The goal of this research was to investigate how sketch-based user interfaces and methods from computer vision could be used for supporting pre-visualisation authoring using a storyboarding approach. The requirements for such a sketch-based storyboarding tool were determined from literature and an interview with Triggerfish Animation Studios. A framework was developed to support sketch-based pre-visualisation authoring using a storyboarding approach. Algorithms for describing user sketches, recognising objects and performing pose estimation were designed to automatically interpret user sketches. A proof of concept prototype implementation of this framework was evaluated in order to assess its usability benefit. It was found that the participants could author pre-visualisations effectively, efficiently and easily. The results of the usability evaluation also showed that the participants were satisfied with the overall design and usability of the prototype tool. The positive and negative findings of the evaluation were interpreted and combined with existing heuristics in order to create a set of guidelines for designing similar sketch-based pre-visualisation authoring tools that apply the storyboarding approach. The successful implementation of the proof of concept prototype tool provides practical evidence of the feasibility of sketch-based pre-visualisation authoring. The positive results from the usability evaluation established that sketch-based interfacing techniques can be used effectively with a storyboarding approach for authoring pre-visualisations without impairing software usability.

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No description available.

This thesis considers the recovery of a sampled image from partial information, based on the 'edges' or zero crossings found in ∇²G filtered versions of the image. A scheme is presented for separating an image into a family of multiresolution images, using low pass filtering, subsampling, and ∇²G filtering. A scheme is also presented for merging this family of ∇²G filtered images to rebuild the original. The recovery of each of the ∇²G filtered images from their 'edges' or zero crossings is then considered. It has been suggested that ∇²G filtered images might be characterized by their zero crossing locations. It is shown that ∇²G filtered images, filtered in 1-D or 2-D are not, in general, uniquely given within a scalar by their zero crossing locations. Two theorems in support of such a suggestion are considered. The differences between the constraints of Logan's theorem and ∇²G filtering are considered, and it is shown that the zero crossings which result from these two situations differ significantly in number and location. Logan's theorem is therefore not applicable to ∇²G filtered images. A recent theorem by Curtis on the adequacy of zero crossings of 2-D functions is also considered. It is shown that the requirements of Curtis' theorem are not satisfied by all ∇²G filtered images. Further, it is shown that it is very difficult to establish if an image meets the requirements of Curtis' theorem. Examples of different ∇²G filtered images with the same zero crossings are also presented. While not all ∇²G filtered images are uniquely characterized by their zero crossing locations, the practical recovery of real camera images from this partial information is considered. An iterative scheme is developed for the reconstruction of a ∇²G filtered image from its sampled zero crossings. The zero crossing samples are localized to the original image sample grid. Experimental results are presented which show that the recovered images, while retaining many of the features of the original, suffer significant loss. It is shown that, in general, the full recovery of these images in a practical situation is not possible from this partial information. From this experimental experience, it is proposed that ∇²G filtered images might be practically recovered from their zero crossings, with some additional characterization of the image in the vicinity of each zero crossing point. A simple, non-iterative scheme is developed for extracting a characterization of the ∇²G filtered image, through the use of an image edge model and a local estimation of a contrast figure in the vicinity of each zero crossing sample. A redrawing algorithm is then used to recover an approximation of the ∇²G filtered image from its zero crossing locations and the extracted characterizations. This system is evaluated using natural scene and synthetic images. Resulting image quality is good, but is shown to vary depending on the nature of the image. The advantages and disadvantages of this technique are discussed. The primary shortcoming of the implemented local estimation technique is an assumption of edge independence. A second approach is developed for characterizing the ∇²G filtered image zero crossings, which eliminates this assumption. This method is based on 2-D filtering, and provides a new technique for the recovery of a ∇²G filtered image from its sampled zero crossings. The method does not involve iteration or the solution of simultaneous equations. Good image reconstruction is shown for natural scene images, with the ∇²G filtered image zero crossings localized only to the original image sample grid. The advantages and disadvantages of this technique are discussed. The application of this recovery from partial information technique is then considered for image compression. A simple coding scheme is developed for representing the zero crossing segments with linear vector segments. A comparative study is then considered, examining the tradeoffs between compression tuning parameters and the resulting recovered image quality. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

A nonlinear switched-capacitor (SC) network for solving the early vision variational problem of edge detection has been designed and constructed using standard SC techniques and a novel nonlinear externally controlled SC resistive element. This new SC element allows, to a limited extent, the form of the variational problem to be "programmable". This allows nonconvex variational problems to be solved by the network using continuation-type methods. Appropriately designed SC networks are guaranteed to converge to a locally stable steady-state. As well, SC networks offer increased accuracy over analog networks composed of nonlinear resistances built from multiple MOSFETs. The operation of the network was analyzed and found to be equivalent to the numerical analysis minimization algorithm of gradient descent. The network's capabilities were demonstrated by "programming" the network to perform the graduated nonconvexity algorithm. A high-level functional network simulation was used to verify the correct operation of the GNC algorithm. A one-dimensional six node CMOS VLSI test chip was designed, simulated and submitted for fabrication. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The themes of this work is to make an instruction set for detection and counting LED in power supply control panel, with using SSE instruction set algorithm. The goal will be to compare function time for optimized and not optimized functions. The first part focuses on SSE instructions introduction, as well as on introduction of some functions using SSE instructions. The second part is dealing with algorithm for detection and counting LEDs and possibility of those algorithms optimizing with SSE instruction set. Next part introduces user interface for developed functions testing. On the very end I compare results of all functions and evaluate these results.