Time-Optimal Gate-Traversing Planner for Autonomous Drone Racing

In drone racing, the time-minimum trajectory is affected by the drone's capabilities, the layout of the race track, and the configurations of the gates (e.g., their shapes and sizes). However, previous studies neglect the configuration of the gates, simply rendering drone racing a waypoint-passing task. This formulation often leads to a conservative choice of paths through the gates, as the spatial potential of the gates is not fully utilized. To address this issue, we present a time-optimal planner that can faithfully model gate constraints with various configurations and thereby generate a more time-efficient trajectory while considering the single-rotor-thrust limits. Our approach excels in computational efficiency which only takes a few seconds to compute the full state and control trajectories of the drone through tracks with dozens of different gates. Extensive simulations and experiments confirm the effectiveness of the proposed methodology, showing that the lap time can be further reduced by taking into account the gate's configuration. We validate our planner in real-world flights and demonstrate super-extreme flight trajectory through race tracks

FINCH: A Blueprint for Accessible and Scientifically Valuable Remote Sensing Satellite Missions

Satellite remote sensing missions have grown in popularity over the past fifteen years due to their ability to cover large swaths of land at regular time intervals, making them suitable for monitoring environmental trends such as greenhouse gas emissions and agricultural practices. As environmental monitoring becomes central in global efforts to combat climate change, accessible platforms for contributing to this research are critical. Many remote sensing missions demand high performance of payloads, restricting research and development to organizations with sufficient resources to address these challenges. Atmospheric remote sensing missions, for example, require extremely high spatial and spectral resolutions to generate scientifically useful results. As an undergraduate-led design team, the University of Toronto Aerospace Team’s Space Systems Division has performed an extensive mission selection process to find a feasible and impactful mission focusing on crop residue mapping. This mission profile provides the data needed to improve crop residue retention practices and reduce greenhouse gas emissions from soil, while relaxing performance requirements relative to many active atmospheric sensing missions. This is accompanied by the design of FINCH, a 3U CubeSat with a hyperspectral camera composed of custom and commercial off-the-shelf components. The team’s custom composite payload, the FINCH Eye, strives to advance performance achieved at this form factor by leveraging novel technologies while keeping design feasibility for a student team a priority. Optical and mechanical design decisions and performance are detailed, as well as assembly, integration, and testing considerations. Beyond its design, the FINCH Eye is examined from operational, timeline, and financial perspectives, and a discussion of the supporting firmware, data processing, and attitude control systems is included. Insight is provided into open-source tools that the team has developed to aid in the design process, including a linear error analysis tool for assessing scientific performance, an optical system tradeoff analysis tool, and data processing algorithms. Ultimately, the team presents a comprehensive case study of an accessible and impactful satellite optical payload design process, in hopes of serving as a blueprint for future design teams seeking to contribute to remote sensing research

Le genre des controverses

Le Dossier analyse des controverses autour du genre et montre les transformations idéologiques et la redéfinition d’antagonismes politiques à partir de dispositifs médiatiques qu’elles impliquent. Un point final est mis aux Échanges sur une sociologie des valeurs. Les Notes de recherche s’intéressent à l’usage des stéréotypes dans la communication interculturelle, à la presse privée égyptienne, à la construction-circulation des cadrages médiatiques de deux groupes d’extrême droite, à l’altération identitaire dans la fiction et à un nouveau modèle éditorial dans l’industrie DVD. En VO, sont étudiés des usages nouveaux des smartphones par des réfugiés syriens en Turquie. Le Focus est mis sur Médiarchie d’Yves Citton et sur La Raison graphique de Jack Goody. Les Notes de lecture rendent compte de plus de 50 publications. This Issue analyses gender controversies and show the ideological transformations and the redefinition of political antagonisms by media dispositifs they involve. The Exchanges on values sociology end. The Research Notes cover the use of stereotypes in intercultural communication, the Egyptian private press, the building and flow of media framings of two right-wing extremist groups, the identity fluctuations in fictional devices and a new publication model in the DVD industry. In Original Version, are examined new uses of smartphones by Syrian refugees in Turkey. The Focus is on Médiarchie by Yves Citton and on The Domestication of the Savage Mind by Jack Goody. The Book Reviews offer succinct overviews and analyses of publications in the field of information and communication