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Siedel T.,Space Applications Services NV. | Bethge S.,Italian Institute of Technology | Hild M.,Berlin Technical University of Applied Sciences
Journal of Automation, Mobile Robotics and Intelligent Systems | Year: 2016

In this article, we propose two model free control schemes that are based on pulse height modulation using low frequencies with the goal to compensate normal friction effects in drive trains that negatively influence the performance of e.g. a standard PID controller. The first control scheme uses pulse height modulation to especially compensate stick slip effects but increases vibration and noise in the drive train. To reduce such side effects a modified phase shifted pulse height control scheme based on multiple actuated joints is introduced. Both control schemes are compared with a standard linear controller as reference and evaluated by using six quality criteria. © 2016, Industrial Research Institute for Automation and Measurements. All rights reserved. Source

Rabbow E.,German Aerospace Center | Rettberg P.,German Aerospace Center | Barczyk S.,German Aerospace Center | Bohmeier M.,German Aerospace Center | And 10 more authors.
Astrobiology | Year: 2012

The multi-user facility EXPOSE-E was designed by the European Space Agency to enable astrobiology research in space (low-Earth orbit). On 7 February 2008, EXPOSE-E was carried to the International Space Station (ISS) on the European Technology Exposure Facility (EuTEF) platform in the cargo bay of Space Shuttle STS-122 Atlantis. The facility was installed at the starboard cone of the Columbus module by extravehicular activity, where it remained in space for 1.5 years. EXPOSE-E was returned to Earth with STS-128 Discovery on 12 September 2009 for subsequent sample analysis. EXPOSE-E provided accommodation in three exposure trays for a variety of astrobiological test samples that were exposed to selected space conditions: either to space vacuum, solar electromagnetic radiation at >110nm and cosmic radiation (trays 1 and 3) or to simulated martian surface conditions (tray 2). Data on UV radiation, cosmic radiation, and temperature were measured every 10s and downlinked by telemetry. A parallel mission ground reference (MGR) experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions. EXPOSE-E performed a successful 1.5-year mission in space. Key Words: Astrobiology-Spacecraft experiments-Spaceflight-ISS-External platform. Astrobiology 12, 374-386. © Mary Ann Liebert, Inc. Source

Pomoell J.,Catholic University of Leuven | Aran A.,University of Barcelona | Jacobs C.,Catholic University of Leuven | Jacobs C.,Space Applications Services NV. | And 3 more authors.
Journal of Space Weather and Space Climate | Year: 2015

We have developed a new version of a model that combines a two-dimensional Sun-to-Earth magnetohydrodynamic (MHD) simulation of the propagation of a CME-driven shock and a simulation of the transport of particles along the interplanetary magnetic field (IMF) line connecting the shock front and the observer. We assume that the shock-accelerated particles are injected at the point along the shock front that intersects this IMF line, i.e. at the cobpoint. Novel features of the model are an improved solar wind model and an enhanced fully automated algorithm to extract the necessary plasma characteristics from the shock simulation. In this work, the new algorithms have been employed to simulate the 2000 April 4 and the 2006 December 13 SEP events. In addition to quantifying the performance of the new model with respect to results obtained using previous versions of the shock-and-particle model, we investigate the semi-empirical relation between the injection rate of shock-accelerated particles, Q, and the jump in speed across the shock, VR, known as the Q(VR) relation. Our results show that while the magnetic field and density compression at the shock front is markedly different than in our previous modeling, the evolution of VR remains largely similar. As a result, we confirm that a simple relation can still be established between Q and VR, which enables the computation of synthetic intensity-time profiles at any location in interplanetary space. Furthermore, the new shock extraction tool is found to yield improved results being in general more robust. These results are important not only with regard to efforts to develop coupled magnetohydrodynamic and particle simulation models, but also to improve space weather related software tools that aim to predict the peak intensities, fluences and proton intensity-time profiles of SEP events (such as the SOLPENCO tool). © J. Pomoell et al., Published by EDP Sciences 2015. Source

Pelka M.,Institute of Mathematical Machines | Majek K.,Institute of Mathematical Machines | Bedkowski J.,Institute of Mathematical Machines | Musialik P.,Institute of Mathematical Machines | And 8 more authors.
12th IEEE International Symposium on Safety, Security and Rescue Robotics, SSRR 2014 - Symposium Proceedings | Year: 2014

In this paper, a Training and Support system for Search and Rescue operations is described. The system is a component of the ICARUS project (http://www.fp7-icarus.eu) which has a goal to develop sensor, robotic and communication technologies for Human Search And Rescue teams. The support system for planning and managing complex SAR operations is implemented as a command and control component that integrates different sources of spatial information, such as maps of the affected area, satellite images and sensor data coming from the unmanned robots, in order to provide a situation snapshot to the rescue team who will make the necessary decisions. Support issues will include planning of frequency resources needed for given areas, prediction of coverage conditions, location of fixed communication relays, etc. The training system is developed for the ICARUS operators controlling UGVs (Unmanned Ground Vehicles), UAVs (Unmanned Aerial Vehicles) and USVs (Unmanned Surface Vehicles) from a unified Remote Control Station (RC2). The Training and Support system is implemented in SaaS model (Software as a Service). Therefore, its functionality is available over the Ethernet. SAR ICARUS teams from different countries can be trained simultaneously on a shared virtual stage. In this paper we will show the multi-robot 3D mapping component (aerial vehicle and ground vehicles). We will demonstrate that these 3D maps can be used for Training purpose. Finally we demonstrate current approach for ICARUS Urban SAR (USAR) and Marine SAR (MSAR) operation training. © 2014 IEEE. Source

Hie S.,University of Craiova | Scares M.,University of Craiova | Badica C.,University of Craiova | Neidhart T.,Space Applications Services NV. | Pinchuk R.,Space Applications Services NV.
ICCC-CONTI 2010 - IEEE International Joint Conferences on Computational Cybernetics and Technical Informatics, Proceedings | Year: 2010

The paper presents a semantic logging framework which allows structured information logging in an agent-based distributed system for chemical incident response. The logging framework is "semantic" because it allows semantic interpretation of logs according to relationships defined between logging events. For example, this approach could help the reconstruction of the order of events that occurred during the response to an incident, thus giving a detailed view of system execution trace, as well as of agents' decisions taken at various decision points during the incident management workflow. We intend to use semantic logs (i) for helping experts to analyze and explain system actions and thus improving system response to future incidents, as well as (ii) for training stakeholders by setting the system to run replaylike simulations of past incident management workflows. © 2010 IEEE. Source

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