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One of the motivations for exploring flapping-wing aerial robotic systems is to seek energy reduction, by maintaining manoeuvrability, compared to conventional unmanned aerial systems. A Flapping Wing Flying Robot (FWFR) can glide in favourable wind conditions, decreasing energy consumption significantly. In addition, it is also necessary to investigate the power consumption of the components in the flapping-wing robot. In this work, two sets of the FWFR components are analyzed in terms of power consumption: a) motor/electronics components and b) a vision system for monitoring the environment during the flight. A measurement device is used to record the power utilization of the motors in the launching and ascending phases of the flight and also in cruising flight around the desired height. Additionally, an analysis of event cameras and stereo vision systems in terms of energy consumption has been performed. The results provide a first step towards decreasing battery usage and, consequently, providing additional flight time.

Perception systems for ornithopters face severe challenges. The harsh vibrations and abrupt movements caused during flapping are prone to produce motion blur and strong lighting condition changes. Their strict restrictions in weight, size, and energy consumption also limit the type and number of sensors to mount onboard. Lightweight traditional cameras have become a standard off-the-shelf solution in many flapping-wing designs. However, bioinspired event cameras are a promising solution for ornithopter perception due to their microsecond temporal resolution, high dynamic range, and low power consumption. This paper presents an experimental comparison between frame-based and an event-based camera. Both technologies are analyzed considering the particular flapping-wing robot specifications and also experimentally analyzing the performance of well-known vision algorithms with data recorded onboard a flapping-wing robot. Our results suggest event cameras as the most suitable sensors for ornithopters. Nevertheless, they also evidence the open challenges for event-based vision on board flapping-wing robots.

Online event-based perception techniques on board robots navigating in complex, unstructured, and dynamic environments can suffer unpredictable changes in the incoming event rates and their processing times, which can cause computational overflow or loss of responsiveness. This paper presents ASAP: a novel event handling framework that dynamically adapts the transmission of events to the processing algorithm, keeping the system responsiveness and preventing overflows. ASAP is composed of two adaptive mechanisms. The first one prevents event processing overflows by discarding an adaptive percentage of the incoming events. The second mechanism dynamically adapts the size of the event packages to reduce the delay between event generation and processing. ASAP has guaranteed convergence and is flexible to the processing algorithm. It has been validated on board a quadrotor and an ornithopter robot in challenging conditions.

Event cameras can capture pixel-level illumination changes with very high temporal resolution and dynamic range. They have received increasing research interest due to their robustness to lighting conditions and motion blur. Two main approaches exist in the literature to feed the event-based processing algorithms: packaging the triggered events in event packages and sending them one-by-one as single events. These approaches suffer limitations from either processing overflow or lack of responsivity. Processing overflow is caused by high event generation rates when the algorithm cannot process all the events in real-time. Conversely, lack of responsivity happens in cases of low event generation rates when the event packages are sent at too low frequencies. This paper presents ASAP, an adaptive scheme to manage the event stream through variable-size packages that accommodate to the event package processing times. The experimental results show that ASAP is capable of feeding an asynchronous event-by-event clustering algorithm in a responsive and efficient manner and at the same time prevents overflow.

The South Pacific is a sensitive location for the variability of the global oceanic thermohaline circulation given that deep waters from the Atlantic Ocean, the Southern Ocean, and the Pacific Basin are exchanged. Here we reconstruct the deep water circulation of the central South Pacific for the last two glacial cycles (from 240,000 years ago to the Holocene) based on radiogenic neodymium (Nd) and lead (Pb) isotope records complemented by benthic stable carbon data obtained from two sediment cores located on the flanks of the East Pacific Rise. The records show small but consistent glacial/interglacial changes in all three isotopic systems with interglacial average values of 5.8 and 18.757 for εNd and 206Pb/204Pb, respectively, whereas glacial averages are 5.3 and 18.744. Comparison of this variability of Circumpolar Deep Water (CDW) to previously published records along the pathway of the global thermohaline circulation is consistent with reduced admixture of North Atlantic Deep Water to CDW during cold stages. The absolute values and amplitudes of the benthic δ13C variations are essentially indistinguishable from other records of the Southern Hemisphere and confirm that the low central South Pacific sedimentation rates did not result in a significant reduction of the amplitude of any of the measured proxies. In addition, the combined detrital Nd and strontium (87Sr/86Sr) isotope signatures imply that Australian and New Zealand dust has remained the principal contributor of lithogenic material to the central South Pacific.

The Intermediate Waters formed in the Southern Ocean are critical for ventilating the thermocline in the Southern Hemisphere Gyres and transporting climatic signals from high to low latitudes on glacial- interglacial time-scales. Despite the importance of the Southern Ocean Intermediate Waters (SOIWs), information on past changes in SOIWs formation is fragmentary, and its impact on the South Pacific Gyre (SPG)’s thermocline largely unknown. Here, we present a 200 kyr record of paired Mg/Ca ratios and stable oxygen isotope from surface and deep dwelling planktonic foraminifera, from the SPG. On average, the Globigerina bulloides Mg/Ca-derived sea surface temperatures show similar conditions during the LGM and Marine Isotope Stage (MIS) 6 (9.4 ◦ C versus 9.8 ◦ C). In contrast, the subsurface temperatures derived from the Mg/Ca values of Globorotalia inflata and Globorotalia truncatulinoides suggest that LGM is ∼3 to ∼2 ◦C colder than MIS 6. Furthermore, at subsurface depths the reconstructed δ18Osw-ivc record (proxy for relative local salinity changes) suggests opposite glacial conditions, with slightly saltier- than-Holocene waters during MIS 6, and fresher-than-Holocene waters during LGM. Contrasting glacial scenarios, plausibly due to changes in the presence of SOIWs at the study site, suggest variable formation and/or advection of SOIWs to the SPG during different glacial stages. The variability in SOIWs is probably driven by the changes in the intensity of the Southern Westerly Winds.

The Intermediate Mode Waters formed in the Southern Ocean are critical for the lower thermocline ventilation process in the Southern Hemisphere Gyres. They also might have served as the most relevant pathways transporting climatic signals from high to low latitudes via the “oceanic tunneling” on glacial/interglacial time scales. Despite the importance of the Southern Ocean Intermediate Waters (SOIWs), our understanding on the long–term evolution, exact advection paths, and impact on the South Pacific Gyre’s thermocline is still fragmentary. Here, we present a 200 kyr record of paired Mg/Ca ratios and stable oxygen isotope from surface dweller and deep dwelling planktonic foraminifera, from the South Pacific Gyre (SPG). On average, the Mg/Ca–derived sea Surface Temperatures (Globigerina bulloides) show similar conditions during the LGM and Marine Isotope Stage (MIS) 6 (9.4 °C versus 9.9 °C). In contrast, our Mg/Ca–derived subsurface temperatures (Globorotalia inflata and Globorotalia truncatulinoides) suggest LGM from ~3 to ~2 °C colder than MIS 6. The reconstructed subsurface ice volume corrected stable oxygen isotope ratio of seawater (δ18Osw-ivc, proxy for local salinity changes) suggests opposing glacial subsurface conditions, i.e., slightly saltier–than–Holocene during MIS 6 to fresher–than–Holocene during MIS 2. Considering that subsurface hydrography at the core site is plausibly driven by the formation and/or advection of SOIWs from the South East Pacific, our results provide further support on the relevance of subsurface processes in the Southern Ocean transferring climatic signals (temperature and salinity) to the SPG. Furthermore, the contrasting subsurface glacial scenarios at the SPG’s thermocline imply that the advection of SOIWs during glacial stages could be highly variable during different glacial stages.

Die Wassermassenzirkulation des Südozeans ist von enormer Bedeutung für den globalen Kohlenstoffzyklus im Hinblick auf die Dynamik des Klimas in Gegenwart und Vergangenheit, da hier alte, nährstoffreiche Wassermassen an die Oberfläche gelangen und neues Zwischen- und Tiefenwasser gebildet wird. Der Südozean ist die bedeutendste Schaltzentrale für den Austausch und die Verbreitung von Wassermassen in den Weltozeanen. Obwohl der pazifische Sektor den größten Teil des Südozeans darstellt, ist der Bereich zwischen Chile und Neuseeland bisher nur unzureichend untersucht. Um diesen weißen Fleck auf unseren paläozeanographischen Karten zu füllen, fand die Ausfahrt SO213 vom 27.12.2010 bis zum 06.03.2011 im Rahmen des BMBF finanzierten Projektes SOPATRA (South Pacific Paleoceanografic Transects) statt. Unterteilt wurde die Expedition in zwei Fahrtabschnitte (Abb. 1A) und führte von Valparaíso, Chile nach Wellington, Neuseeland. Insgesamt konzentrierten sich die Untersuchungen auf fünf Arbeitsgebiete: die Challenger Fracture Zone (CFZ), den Chile Rücken (ChiRi), den Ostpazifischen Rücken (EPR), das Südwestpazifische Becken (SWB) und den Neuseeländischen Kontinentalrand (NZM) südlich des Chatham Rise (Abb. 1B). Das wissenschaftliche Programm an Board setzte sich aus paläozeanographischen, geophysikalischen und vulkanologischen Untersuchungen zusammen. Zielsetzung der Vulkanologie war es, zu untersuchen, wie Hotspots mit Spreizungszonen interagieren und ob Hotspots durch Prozesse in den Kontinentalplatten oder durch aufsteigende Mantelplumes verursacht werden. Mit Hilfe der geophysikalischen Untersuchungen sollten potentielle Kernlokationen für das Integrated Ocean Drilling Program (IODP) identifiziert werden. Des Weiteren sollten die aufgezeichneten Seismikprofile Hintergrundinformationen für den IODP Antrag CESOP (Cenozoic Southern Ocean Pacific) liefern. Die meisten Ziele konnten wie geplant umgesetzt werden. Dies beinhaltete die Beprobung und Gewinnung von Sedimentoberfläc

Die Wassermassenzirkulation des Südozeans ist von enormer Bedeutung für den globalen Kohlenstoffzyklus im Hinblick auf die Dynamik des Klimas in Gegenwart und Vergangenheit, da hier alte, nährstoffreiche Wassermassen an die Oberfläche gelangen und neues Zwischen- und Tiefenwasser gebildet wird. Der Südozean ist die bedeutendste Schaltzentrale für den Austausch und die Verbreitung von Wassermassen in den Weltozeanen. Obwohl der pazifische Sektor den größten Teil des Südozeans darstellt, ist der Bereich zwischen Chile und Neuseeland bisher nur unzureichend untersucht. Um diesen weißen Fleck auf unseren paläozeanographischen Karten zu füllen, fand die Ausfahrt SO213 vom 27.12.2010 bis zum 06.03.2011 im Rahmen des BMBF finanzierten Projektes SOPATRA (South Pacific Paleoceanografic Transects) statt. Unterteilt wurde die Expedition in zwei Fahrtabschnitte (Abb. 1A) und führte von Valparaíso, Chile nach Wellington, Neuseeland. Insgesamt konzentrierten sich die Untersuchungen auf fünf Arbeitsgebiete: die Challenger Fracture Zone (CFZ), den Chile Rücken (ChiRi), den Ostpazifischen Rücken (EPR), das Südwestpazifische Becken (SWB) und den Neuseeländischen Kontinentalrand (NZM) südlich des Chatham Rise (Abb. 1B). Das wissenschaftliche Programm an Board setzte sich aus paläozeanographischen, geophysikalischen und vulkanologischen Untersuchungen zusammen. Zielsetzung der Vulkanologie war es, zu untersuchen, wie Hotspots mit Spreizungszonen interagieren und ob Hotspots durch Prozesse in den Kontinentalplatten oder durch aufsteigende Mantelplumes verursacht werden. Mit Hilfe der geophysikalischen Untersuchungen sollten potentielle Kernlokationen für das Integrated Ocean Drilling Program (IODP) identifiziert werden. Des Weiteren sollten die aufgezeichneten Seismikprofile Hintergrundinformationen für den IODP Antrag CESOP (Cenozoic Southern Ocean Pacific) liefern. Die meisten Ziele konnten wie geplant umgesetzt werden. Dies beinhaltete die Beprobung und Gewinnung von Sedimentoberfläc