Examinando por Autor "Rivas, J."
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Publicación Acceso Abierto Data Analysis and Results of the Radiation-Tolerant Collaborative Computer On-Board OPTOS CubeSat(Hindawi, 2019-02-12) Rodríguez, Santiago; Ibarmia, S.; Rivas, J.; López Buedo, S.; López Ongil, C.; Portela García, M.; Martín-Ortega, Alberto; Martín-Ortega, Alberto; de Mingo Martín, José Ramón; Instituto Nacional de Técnica Aeroespacial (INTA); Universidad Carlos III de Madrid (UC3M); Universidad Autónoma de Madrid (UAM)The current evolution of the space missions demands to increase the computing capacities of the on-board computer while reducing its power consumption. This requirement evolves faster than the ability of the manufacturers to develop better space-qualified processors. To meet the strong requirements, the National Institute of Aerospace Technology has developed a distributed on-board computer based on commercial off-the-shelf (COTS). This computer, named OPTOS, provides enhanced computational capacities with respect to what computers of other small satellites typically provide. To maintain the reliability needed to perform typical critical activities such as real-time maintenance or current surveillance, authors have conceived a set of collaborative hardening techniques, taking advantage of the distributed architecture of the OPTOS On-Board Computer. The 3-year mission data analysis shows the feasibility of the collaborative hardening techniques implemented, despite using SEU sensitive devices. The authors describe the processes and tools used to analyse the data and clearly expose the functional errors found at unit level, while the system remains unfaulty and reliable thanks to the collaborative techniques.Publicación Restringido DREAMS-SIS: The Solar Irradiance Sensor on-board the ExoMars 2016 lander(Elsevier, 2017-07-01) Arruego, I.; Jiménez Martín, Juan José; Martínez Oter, J.; Álvarez Ríos, F. J.; González Guerrero, M.; Rivas, J.; Azcue, J.; Martín, I.; Toledo, D.; Gómez, L.; Jiménez Michavila, M.; Yela González, M.; Apéstigue, Víctor; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)The Solar Irradiance Sensor (SIS) was part of the DREAMS (Dust characterization, Risk assessment, and Environment Analyzer on the Martian Surface) payload package on board the ExoMars 2016 Entry and Descent Module (EDM), “Schiaparelli”. DREAMS was a meteorological station aimed at the measurement of several atmospheric parameters, as well as the presence of electric fields, during the surface operations of EDM. DREAMS-SIS is a highly miniaturized lightweight sensor designed for small meteorological stations, capable of estimating the aerosol optical depth (AOD) several times per sol, as well as performing a direct measurement of the global (direct plus scattered) irradiance on the Martian surface in the spectral range between 200 and 1100 nm. AOD is estimated from the irradiance measurements at two different spectral bands – Ultraviolet (UV) and near infrared (NIR) – which also enables color index (CI) analysis for the detection of clouds. Despite the failure in the landing of Schiaparelli, DREAMS-SIS is a valuable precursor for new developments being carried-on at present. The concept and design of DREAMS-SIS are here presented and its operating principles, supported by preliminary results from a short validation test, are described. Lessons learnt and future work towards a new generation of Sun irradiance sensors is also outlined.Publicación Restringido Early SEU sensitivity assessment for collaborative hardening techniques: A case study of OPTOS processing architecture(Elsevier, 2019-03-06) Portela García, M.; Rodríguez, Santiago; Rivas, J.; López Buedo, S.; Martín-Ortega, Alberto; Martín-Ortega, Alberto; de Mingo Martín, José Ramón; Instituto Nacional de Técnica Aeroespacial (INTA); Universidad Carlos III de Madrid (UC3M); Universidad Autónoma de Madrid (UAM)Nowadays, space missions face a relentless increase in requirements for on-board computers. Higher computing capacities are needed, while the power consumption, mass and area must be reduced. Unfortunately, requirements evolve faster than the ability of manufacturers to develop better space-qualified processors, so techniques that allow designers to use COTS (commercial, off-the-shelf) components are needed. As such, collaborative hardening is a powerful an efficient technique to guarantee the reliability of the safety critical tasks of a satellite. However, the stringent dependability requirements of space missions call for comprehensive on-ground validation of any design using COTS components before it can be used in orbit. In this work, we present the collaborative hardening techniques developed for the OPTOS satellite, and how it was on-ground validated against the effects of radiation. We introduce a methodology for early SEU sensitivity assessment based on fault injection through an autonomous emulation system. Fault injection is performed at system level, not unit level, to validate the safety critical techniques implemented by the collaborative architecture. The experimental results show that, while single units are vulnerable to the effects of radiation, the reliability of the system as a whole is not compromised.Publicación Acceso Abierto OWLS: a ten-year history in optical wireless links for intra-satellite communications(Institute of Electrical and Electronics Engineers 27(9): 1599-1611(2009), 2009-12-10) Arruego, I.; Guerrero, H.; Rodríguez, Santiago; Martínez Oter, J.; Jiménez, J. J.; Domínguez, J. A.; Rivas, J.; Álvarez, M. T.; Gallego, P.; Azcue, J.; Ruiz de Galarreta, C.; Martín, B.; Álvarez Herrero, A.; Díaz Michelena, M.; Martín, I.; Tamayo, R.; Reina, M.; Gutiérrez, M. J.; Sabau, L.; Torres, J.; Martín-Ortega, Alberto; Martín-Ortega, Alberto; de Mingo Martín, José Ramón; Apéstigue, Víctor; Sánchez - Valdepeñas García - Moreno, Jesús; Samblas Iglesias, JuanThe application of Optical Wireless Links to intra- Spacecraft communications (OWLS) is presented here. This work summarizes ten years of developments, ranging from basic optoelectronic parts and front-end electronics, to different inorbit demonstrations. Several wireless applications were carried out in representative environments at ground level, and on in-flight experiments. A completely wireless satellite will be launched at the beginning of 2010. The benefits of replacing standard data wires and connectors with wireless systems are: mass reduction, flexibility, and simplification of the Assembly, Integration and Tests phases (AIT). However, the Aerospace and Defense fields need high reliability solutions. The use of COTS (Commercial-Off-The- Shelf) parts in these fields require extensive analyses in order to attain full product assurance. The current commercial optical wireless technology needs a deep transformation in order to be fully applicable in the aforementioned fields. Finally, major breakthroughs for the implementation of optical wireless links in Space will not be possible until dedicated circuits such as mixed analog/digital ASICs are developed. Once these products become available, it will also be possible to extend optical wireless links to other applications, such as Unmanned Air and Underwater Vehicles (UAV and UUV). The steps taken by INTA to introduce Optical Wireless Links in the Space environment are presented in this paper.Publicación Acceso Abierto Radiation and Dust Sensor for Mars Environmental Dynamic Analyzer Onboard M2020 Rover(Multidisciplinary Digital Publishing Institute (MDPI), 2022-04-10) Jiménez, J. J.; Boland, J.; Lemmon, M. T.; García Menéndez, Elisa; Rivas, J.; Azcue, J.; Bastide, L.; Andrés Santiuste, N.; Martínez Oter, J.; González Guerrero, M.; Toledo, D.; Álvarez Rios, F. J.; Serrano, F.; Martín Vodopivec, B.; Manzano, J.; López Heredero, R.; Carrasco, I.; Aparicio, S.; Carretero, Á.; MacDonald, D. R.; Moore, L. B.; Alcacera Gil, María Ángeles; Fernández Viguri, J. A.; Martín, I.; Yela González, M.; Álvarez, M.; Manzano, P.; Martín, J. A.; Reina, M.; Urquí, R.; Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Córdoba, E.; Leiter, R.; Thompson, A.; Madsen, S.; Smith, M. D.; Viúdez Moreiras, Daniel; Saix López, A.; Sánchez Lavega, A.; Apéstigue, Víctor; Gómez Martín, L.; Gonzalo Melchor, Alejandro; Martínez, G. M.; de Mingo Martín, José Ramón; Gómez Elvira, J.; Martín-Ortega, Alberto; Arruego, I.; del Hoyo Gordillo, Juan Carlos; Martín-Ortega, Alberto; González Hernández, Carmen; Martín-Ortega, Alberto; Instituto Nacional de Técnica Aeroespacial (INTA); Comunidad de Madrid; Gobierno Vasco; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); National Aeronautics and Space Administration (NASA)The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars’ surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars’ surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.