Automatic Model Based Dataset Generation for Fast and Accurate Crop and Weeds Detection

Selective weeding is one of the key challenges in the field of agriculture robotics. To accomplish this task, a farm robot should be able to accurately detect plants and to distinguish them between crop and weeds. Most of the promising state-of-the-art approaches make use of appearance-based models trained on large annotated datasets. Unfortunately, creating large agricultural datasets with pixel-level annotations is an extremely time consuming task, actually penalizing the usage of data-driven techniques. In this paper, we face this problem by proposing a novel and effective approach that aims to dramatically minimize the human intervention needed to train the detection and classification algorithms. The idea is to procedurally generate large synthetic training datasets randomizing the key features of the target environment (i.e., crop and weed species, type of soil, light conditions). More specifically, by tuning these model parameters, and exploiting a few real-world textures, it is possible to render a large amount of realistic views of an artificial agricultural scenario with no effort. The generated data can be directly used to train the model or to supplement real-world images. We validate the proposed methodology by using as testbed a modern deep learning based image segmentation architecture. We compare the classification results obtained using both real and synthetic images as training data. The reported results confirm the effectiveness and the potentiality of our approach.Comment: To appear in IEEE/RSJ IROS 201

A stratified rendering algorithm for virtual walkthroughs of large environments

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (p. 73-74).by Rebecca Wen Fei Xiong.M.S

The Use of Historical Data in Rule-Based Modelling for Scenarios to Improve Resilience within the Building Stock

Digital documentation has become integral to the preservation, analysis and communication of historical sites. New platforms are now being developed that involve complex 3D models and allow the analysis of spatial data. These include procedural modelling, a technique that enables the rapid development of ‘dynamic’ 3D environments, and generation of simulations for entire cities, resulting in low cost, high resolution 3D city models. Though procedural modelling has been used in the context of archaeology to ‘recreate’ cities at specific historic time points, the use of historical data in the development of rule-based procedural models for current cities has been little explored. Here, we test the extent to which construction age data, historical building regulations and architectural knowledge can be used in the generation of procedural rules, and the level of detail and potential impact that these models may have. Rather than creating an accurate representation of the city, we instead seek to simulate the way in which urban areas are likely to behave under certain conditions, in order to test what-if? planning scenarios. This allows us to explore more flexible ways of digitally ‘creating’ cities, past and present, and to gain insights into underlying ‘rules’ that govern their physical form

Towards an Ethics of Distance: Representation, Free Production and Virtuality

This article takes it inspiration from a crisis between Deleuzian free production and representation in contemporary virtual and digital culture. The aim is to sketch a different ethics to the ethics of difference between free production and representation as described by Deleuze and Guattari and invoked by Michel Foucault in his preface to Anti-Oedipe. This article outlines the case for an ethical relationality between these two structures which reflects the socio-political and ethical exigencies of our virtual and digital cultures: specifically, an ethics of relationality derived paradoxically from the distance inscribed in ethical philosophy. Drawing on an amalgamation of Ricoeurean ethics and social constructionism in a definition of selfhood, I argue for the need to stand back from the distanciating effects of the virtual revolution – not with a view to approximating the cultural politics of specificity in the logic of representation – but to see in the gap in "distance from" specificity, a space of ethical and philosophical agency wherein lies the value-added of otherness

A Framework for Dynamic Terrain with Application in Off-road Ground Vehicle Simulations

The dissertation develops a framework for the visualization of dynamic terrains for use in interactive real-time 3D systems. Terrain visualization techniques may be classified as either static or dynamic. Static terrain solutions simulate rigid surface types exclusively; whereas dynamic solutions can also represent non-rigid surfaces. Systems that employ a static terrain approach lack realism due to their rigid nature. Disregarding the accurate representation of terrain surface interaction is rationalized because of the inherent difficulties associated with providing runtime dynamism. Nonetheless, dynamic terrain systems are a more correct solution because they allow the terrain database to be modified at run-time for the purpose of deforming the surface. Many established techniques in terrain visualization rely on invalid assumptions and weak computational models that hinder the use of dynamic terrain. Moreover, many existing techniques do not exploit the capabilities offered by current computer hardware. In this research, we present a component framework for terrain visualization that is useful in research, entertainment, and simulation systems. In addition, we present a novel method for deforming the terrain that can be used in real-time, interactive systems. The development of a component framework unifies disparate works under a single architecture. The high-level nature of the framework makes it flexible and adaptable for developing a variety of systems, independent of the static or dynamic nature of the solution. Currently, there are only a handful of documented deformation techniques and, in particular, none make explicit use of graphics hardware. The approach developed by this research offloads extra work to the graphics processing unit; in an effort to alleviate the overhead associated with deforming the terrain. Off-road ground vehicle simulation is used as an application domain to demonstrate the practical nature of the framework and the deformation technique. In order to realistically simulate terrain surface interactivity with the vehicle, the solution balances visual fidelity and speed. Accurately depicting terrain surface interactivity in off-road ground vehicle simulations improves visual realism; thereby, increasing the significance and worth of the application. Systems in academia, government, and commercial institutes can make use of the research findings to achieve the real-time display of interactive terrain surfaces

An American prototopia: or Peachtree City as an inadvertent, sustainable solution to urban sprawl

Peachtree City is a city with a secondary transportation network, known as the path system. This paperseeks to determine why the path system is so successful and whether there are fundamental spatial,configurational properties which underpin its achievement. This paper examines the axial-line network ofpaths as a distinct network then as part of the larger, combined system of both paths and roads.The finding of this paper is that the cart path system, although unintelligible in its own right, serves thepurpose of reducing the overall number of cul-de-sacs in the city whilst increasing its axial ringiness. Anew measure for calculating the spatial signature of sprawl is suggested - the proportion and distribution ofcircuit lengths in the axial map. The paper continues by discussing the social, economic and environmentalbenefits of the path system, with the proviso that these benefits arise only from a successful system and thata partial factor contributing to this must be the spatial regularities revealed in the axial analyses. It concludsby suggesting that without the cart path system, Peachtree City would consist of nothing more thanaggregations of typical suburban developments with one or two primary road-entrances accessed fromarterial-roads and containing a high ratio of cul-de-sacs.This paper concludes by suggesting how Peachtree City could be held to be the blue-print of a ?protopia?,presenting a principle by which American suburbia could be transformed into sustainable communities andyet do so in a manner which would be distinctly American in character and hence palatable to its residentsunlike many current, public-transport focused proposals