Dynamic Landing of an Autonomous Quadrotor on a Moving Platform in Turbulent Wind Conditions

Autonomous landing on a moving platform presents unique challenges for multirotor vehicles, including the need to accurately localize the platform, fast trajectory planning, and precise/robust control. Previous works studied this problem but most lack explicit consideration of the wind disturbance, which typically leads to slow descents onto the platform. This work presents a fully autonomous vision-based system that addresses these limitations by tightly coupling the localization, planning, and control, thereby enabling fast and accurate landing on a moving platform. The platform's position, orientation, and velocity are estimated by an extended Kalman filter using simulated GPS measurements when the quadrotor-platform distance is large, and by a visual fiducial system when the platform is nearby. The landing trajectory is computed online using receding horizon control and is followed by a boundary layer sliding controller that provides tracking performance guarantees in the presence of unknown, but bounded, disturbances. To improve the performance, the characteristics of the turbulent conditions are accounted for in the controller. The landing trajectory is fast, direct, and does not require hovering over the platform, as is typical of most state-of-the-art approaches. Simulations and hardware experiments are presented to validate the robustness of the approach.Comment: 7 pages, 8 figures, ICRA2020 accepted pape

Touch the Wind: Simultaneous Airflow, Drag and Interaction Sensing on a Multirotor

Disturbance estimation for Micro Aerial Vehicles (MAVs) is crucial for robustness and safety. In this paper, we use novel, bio-inspired airflow sensors to measure the airflow acting on a MAV, and we fuse this information in an Unscented Kalman Filter (UKF) to simultaneously estimate the three-dimensional wind vector, the drag force, and other interaction forces (e.g. due to collisions, interaction with a human) acting on the robot. To this end, we present and compare a fully model-based and a deep learning-based strategy. The model-based approach considers the MAV and airflow sensor dynamics and its interaction with the wind, while the deep learning-based strategy uses a Long Short-Term Memory (LSTM) neural network to obtain an estimate of the relative airflow, which is then fused in the proposed filter. We validate our methods in hardware experiments, showing that we can accurately estimate relative airflow of up to 4 m/s, and we can differentiate drag and interaction force.Comment: The first two authors contributed equall

A Distributed Pipeline for Scalable, Deconflicted Formation Flying

Reliance on external localization infrastructure and centralized coordination are main limiting factors for formation flying of vehicles in large numbers and in unprepared environments. While solutions using onboard localization address the dependency on external infrastructure, the associated coordination strategies typically lack collision avoidance and scalability. To address these shortcomings, we present a unified pipeline with onboard localization and a distributed, collision-free motion planning strategy that scales to a large number of vehicles. Since distributed collision avoidance strategies are known to result in gridlock, we also present a decentralized task assignment solution to deconflict vehicles. We experimentally validate our pipeline in simulation and hardware. The results show that our approach for solving the optimization problem associated with motion planning gives solutions within seconds in cases where general purpose solvers fail due to high complexity. In addition, our lightweight assignment strategy leads to successful and quicker formation convergence in 96-100% of all trials, whereas indefinite gridlocks occur without it for 33-50% of trials. By enabling large-scale, deconflicted coordination, this pipeline should help pave the way for anytime, anywhere deployment of aerial swarms.Comment: 8 main pages, 1 additional page, accepted to RA-L and IROS'2

Dynamic Landing of an Autonomous Quadrotor on a Moving Platform in Turbulent Wind Conditions

© 2020 IEEE. Autonomous landing on a moving platform presents unique challenges for multirotor vehicles, including the need to accurately localize the platform, fast trajectory planning, and precise/robust control. Previous works studied this problem but most lack explicit consideration of the wind disturbance, which typically leads to slow descents onto the platform. This work presents a fully autonomous vision-based system that addresses these limitations by tightly coupling the localization, planning, and control, thereby enabling fast and accurate landing on a moving platform. The platform's position, orientation, and velocity are estimated by an extended Kalman filter using simulated GPS measurements when the quadrotor-platform distance is large, and by a visual fiducial system when the platform is nearby. The landing trajectory is computed online using receding horizon control and is followed by a boundary layer sliding controller that provides tracking performance guarantees in the presence of unknown, but bounded, disturbances. To improve the performance, the characteristics of the turbulent conditions are accounted for in the controller. The landing trajectory is fast, direct, and does not require hovering over the platform, as is typical of most stateof-the-art approaches. Simulations and hardware experiments are presented to validate the robustness of the approach

De la fàbrica Lumière a la societat del desconcert : anàlisi semiòtic del cinema europeu de la crisi sociolaboral

Aquest treball proposa una mirada als residus de la crisi sociolaboral europea a través dels discursos cinematogràfics. L'objectiu és relacionar, mitjançant la semiologia, els recursos fílmics que s'utilitzen per expressar un determinat caràcter social. Per fer-ho, l'anàlisi dissecciona els discursos de les pel·lícules A fábrica de nada (Pinho, 2017) i Deux jours, une nuit (Dardenne, 2015), els quals prèviament són contextualitzats mitjanant una anàlisi historicista dels principals codis que el cinema sociolaboral ha presentat durant el segle XX.Este trabajo propone una mirada a los residuos de la crisis sociolaboral europea a través de los discursos cinematográficos. El objetivo es relacionar, mediante la semiología, los recursos fílmicos que se utilizan para expresar un determinado carácter social. Para ello, el análisis disecciona los discursos de las películas A fábrica de nada (Pinho, 2017) y Deux jours, une nuit (Dardenne, 2015), los cuales previamente son contextualizados mediante un análisis historicista de los principales códigos que el cine sociolaboral ha presentado durante el siglo XX.This thesis proposes a look at the residues of the European socio-labor crisis through cinematic discourses. The aim is to relate, through semiology, the filmic resources used to express a certain social character. To do so, the analysis dissects the discourses of the films A fábrica de nada (Pinho, 2017) and Deux jours, une nuit (Dardenne, 2015), which are previously contextualized through a historicist analysis of the main codes that socio-labor cinema has presented during the twentieth century

A Whisker-inspired Fin Sensor for Multi-directional Airflow Sensing

This work presents the design, fabrication, and characterization of an airflow sensor inspired by the whiskers of animals. The body of the whisker was replaced with a fin structure in order to increase the air resistance. The fin was suspended by a micro-fabricated spring system at the bottom. A permanent magnet was attached beneath the spring, and the motion of fin was captured by a readily accessible and low- cost 3D magnetic sensor located below the magnet. The sensor system was modeled in terms of the dimension parameters of fin and the spring stiffness, which were optimized to improve the performance of the sensor. The system response was then characterized using a commercial wind tunnel and the results were used for sensor calibration. The sensor was integrated into a micro aerial vehicle (MAV) and demonstrated the capability of capturing the velocity of the MAV by sensing the relative airflow during flight.Air Force Office of Scientific Research (Award MURI FA9550-19-1-0386)National Science Foundation (NSF) (Award BCS-1921251

Poly (ADP-ribose) polymerase inhibitors in solid tumours: Systematic review and meta-analysis

Poly (ADP-ribose) polymerase-inhibitors (PARPis) showed antitumour activity in BRCA1/2-mutated cancers, with more heterogeneous outcomes in tumours harbouring mutations that impair other genes involved in the DNA homologous recombination repair (HRR) or wild-type (wt)

Poly (ADP-ribose) polymerase inhibitors in solid tumours: Systematic review and meta-analysis

Background: Poly (ADP-ribose) polymerase-inhibitors (PARPis) showed antitumour activity in BRCA1/2-mutated cancers, with more heterogeneous outcomes in tumours harbouring mutations that impair other genes involved in the DNA homologous recombination repair (HRR) or wild-type (wt). Methods: We conducted a systematic review and meta-analysis to better assess the role of PARPis in the treatment of metastatic solid tumours, with and without BRCA1/2 mutations. The primary end-point was progression-free survival (PFS). The secondary end-points were overall response rate (ORR) and overall survival (OS). A random-effects model was applied. Results: Twenty-nine studies (8,839 patients) were included. PFS was significantly improved (hazard ratio [HR]: 0.59, 95% confidence interval [CI]: 0.51e0.68, p < 0.001), without being affected by BRCA mutational status (p Z 0.65). Significant subgroup differences were observed with regard to the tumour site (p Z 0.001), line of therapy (p Z 0.002), control arm (p < 0.001), type of PARPi (p < 0.001) and trials\u2019 phase (p Z 0.006). PARPis were associated with ORR (relative risk: 1.35, 95% CI: 1.16e1.56, p < 0.001), with significant subgroup differences observed with regard to treatment line (p Z 0.03), control arm (p Z 0.04) and PARPis (p < 0.001) and independent of mutational status (p Z 0.44), tumour site (p Z 0.86) and trials\u2019 phase (p Z 0.09). OS was significantly improved by PARPis (HR: 0.86, 95% CI: 0.80e0.92, p < 0.001), regardless of mutational status (p Z 0.57), tumour site (p Z 0.82), treatment line (p Z 0.22), control arm (p Z 0.21), PARPis (p Z 0.30) and trials\u2019 phase (p Z 0.26). Finally, an exploratory subgroup analysis showed a significant PFS improvement (HR: 0.51, 95% CI: 0.43e0.60, p < 0.001) with PARPis in BRCA-wt/HRRdeficient tumours. Conclusion: Our results confirm the efficacy of already approved PARPi-based treatments in BRCA1/2-mutant solid tumours, support their role also in BRCA-independent HRR-deficient tumours and suggest a potentially broader efficacy in some wt tumours, perhaps with appropriate therapeutic partners. Prospective studies are warranted

Silencis, presències, rizomes: cròniques d'un curs d'investigació basada en les arts

Curs 2021-2022, Facultat de Belles Arts. UBAquesta publicació és un recull de les experiències d'aprentatge i dels moviments d'un grup de docents i estudiants que formen part d'un curs d'Investigació basada en les Arts (IBA). En el present document es presenten les quatre formalitzacions dels processos d'indagació realitzades al llarg d’aquest curs d’IBA al voltant de la natura com a constructe social; l’antropocè, el capitalocè i el chthulucè; el colonialisme; i, per últim, les pedagogiespost-humanistes. Tot i la separació en grups, tots els treballs es nodreixen de manera co-constituent i estableixen relacions de reciprocitat

Overall survival of CDK4/6-inhibitors-based treatments in clinically relevant subgroups of metastatic breast cancer: systematic review and meta-analysis

Background: Cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors þ endocrine therapy (ET) prolonged progression-free survival as first- or second-line therapy for hormone receptor-positive (HRþ)/HER2-negative metastatic breast cancer prognosis. Given the recent publication of overall survival (OS) data for the 3 CDK4/6-inhibitors, we performed a meta-analysis to identify a more precise and reliable benefit from such treatments in specific clinical subgroups. Methods: We conducted a systematic literature search to select all available phase II or III randomized clinical trials of CDK4/6-inhibitors þ ET reporting OS data in first- or second-line therapy of HRþ/HER2-negative pre- or postmenopausal metastatic breast cancer. A random effect model was applied for the analyses. Heterogeneity was assessed with I2statistic. Subgroup analysis was performed to explore the effect of study-level factors. The project was registered in the Open Science Framework database (doi: 10.17605/OSF.IO/TNZQP). Results: Six studies were included in our analyses (3421 patients). A clear OS benefit was observed in patients without (hazard ratio [HR] 1⁄4 0.68, 95% confidence interval [CI] 1⁄4 0.54 to 0.85, I2 1⁄4 0.0%) and with visceral involvement (HR 1⁄4 0.76, 95% CI 1⁄4 0.65 to 0.89, I2 1⁄4 0.0%), with at least 3 metastatic sites (HR 1⁄4 0.75, 95% CI 1⁄4 0.60 to 0.94, I2 1⁄4 11.6%), in an endocrine-resistant (HR 1⁄4 0.79, 95% CI 1⁄4 0.67 to 0.93, I2 1⁄4 0.0%) and sensitive subset (HR 1⁄4 0.73, 95% CI 1⁄4 0.61 to 0.88, I2 1⁄4 0.0%), for younger than 65 years (HR 1⁄4 0.80, 95% CI 1⁄4 0.67 to 0.95, I2 1⁄4 0.0%) and 65 years or older (HR 1⁄4 0.71, 95% CI 1⁄4 0.53 to 0.95, I2 1⁄4 44.4%), in postmenopausal (HR 1⁄4 0.76, 95% CI 1⁄4 0.67 to 0.86, I2 1⁄4 0.0%) and pre- or perimenopausal setting (HR 1⁄4 0.76, 95% CI 1⁄4 0.60 to 0.96, I2 1⁄4 0.0%) as well as in chemotherapy-naive patients (HR 1⁄4 0.72, 95% CI 1⁄4 0.55 to 0.93, I2 1⁄4 0.0%). Conclusions: CDK4/6-inhibitors þ ET combinations compared with ET alone improve OS independent of age, menopausal status, endocrine sensitiveness, and visceral involvement and should be preferred as upfront therapy instead of endocrine monotherapy