Particle telescope aboard FORESAIL-1 : Simulated performance

The Particle Telescope (PATE) of FORESAIL-1 mission is described. FORESAIL-1 is a CubeSat mission to polar Low Earth Orbit. Its scientific objectives are to characterize electron precipitation from the radiation belts and to observe energetic neutral atoms (ENAs) originating from the Sun during the strongest solar flares. For that purpose, the 3-unit CubeSat carries a particle telescope that measures energetic electrons in the nominal energy range of 80–800 keV in seven energy channels and energetic protons at 0.3–10 MeV in ten channels. In addition, particles penetrating the whole telescope at higher energies will be measured in three channels: one >800 keV electron channel, two integral proton channels at >10 MeV energies. The instrument contains two telescopes at right angles to each other, one measuring along the spin axis of the spacecraft and one perpendicular to it. During a spin period (nominally 15 s), the rotating telescope will, thus, deliver angular distributions of protons and electrons, at 11.25-degree clock-angle resolution, which enables one to accurately determine the pitch-angle distribution and separate the trapped and precipitating particles. During the last part of the mission, the rotation axis will be accurately pointed toward the Sun, enabling the measurement of the energetic hydrogen from that direction. Using the geomagnetic field as a filter and comparing the rates observed by the two telescopes, the instrument can observe the solar ENA flux for events similar to the only one so far observed in December 2006. We present the Geant4-simulated energy and angular response functions of the telescope and assess its sensitivity showing that they are adequate to address the scientific objectives of the mission.The Particle Telescope (PATE) of FORESAIL-1 mission is described. FORESAIL-1 is a CubeSat mission to polar Low Earth Orbit. Its scientific objectives are to characterize electron precipitation from the radiation belts and to observe energetic neutral atoms (ENAs) originating from the Sun during the strongest solar flares. For that purpose, the 3-unit CubeSat carries a particle telescope that measures energetic electrons in the nominal energy range of 80-800 keV in seven energy channels and energetic protons at 0.3-10 MeV in ten channels. In addition, particles penetrating the whole telescope at higher energies will be measured in three channels: one >800 keV electron channel, two integral proton channels at >10 MeV energies. The instrument contains two telescopes at right angles to each other, one measuring along the spin axis of the spacecraft and one perpendicular to it. During a spin period (nominally 15 s), the rotating telescope will, thus, deliver angular distributions of protons and electrons, at 11.25-degree clock-angle resolution, which enables one to accurately determine the pitch-angle distribution and separate the trapped and precipitating particles. During the last part of the mission, the rotation axis will be accurately pointed toward the Sun, enabling the measurement of the energetic hydrogen from that direction. Using the geomagnetic field as a filter and comparing the rates observed by the two telescopes, the instrument can observe the solar ENA flux for events similar to the only one so far observed in December 2006. We present the Geant4-simulated energy and angular response functions of the telescope and assess its sensitivity showing that they are adequate to address the scientific objectives of the mission. (C) 2019 COSPAR. Published by Elsevier Ltd. All rights reserved.Peer reviewe

Particle telescope aboard FORESAIL-1: Simulated performance

The Particle Telescope (PATE) of FORESAIL-1 mission is described. FORESAIL-1 is a CubeSat mission to polar Low Earth Orbit. Its scientific objectives are to characterize electron precipitation from the radiation belts and to observe energetic neutral atoms (ENAs) originating from the Sun during the strongest solar flares. For that purpose, the 3-unit CubeSat carries a particle telescope that measures energetic electrons in the nominal energy range of 80–800 keV in seven energy channels and energetic protons at 0.3–10 MeV in ten channels. In addition, particles penetrating the whole telescope at higher energies will be measured in three channels: one >800 keV electron channel, two integral proton channels at >10 MeV energies. The instrument contains two telescopes at right angles to each other, one measuring along the spin axis of the spacecraft and one perpendicular to it. During a spin period (nominally 15 s), the rotating telescope will, thus, deliver angular distributions of protons and electrons, at 11.25-degree clock-angle resolution, which enables one to accurately determine the pitch-angle distribution and separate the trapped and precipitating particles. During the last part of the mission, the rotation axis will be accurately pointed toward the Sun, enabling the measurement of the energetic hydrogen from that direction. Using the geomagnetic field as a filter and comparing the rates observed by the two telescopes, the instrument can observe the solar ENA flux for events similar to the only one so far observed in December 2006. We present the Geant4-simulated energy and angular response functions of the telescope and assess its sensitivity showing that they are adequate to address the scientific objectives of the mission

Scientific Data Path of the Particle Telescope Onboard the FORESAIL-1 Satellite

Field Programmable Gate Arrays (FPGAs) are compelling for use in satellites, which do not have high budgets. Radiation can however cause errors in FPGAs and this has to be taken into account in the design process. FPGAs can be made with different technologies, and these technologies have different sensitivities to radiation. Nowadays Flash-based FPGAs start to be as good, or better than traditionally used antifuse technology, when radiation hardening is implemented during the design process. Flash technology also has other strengths when comparing to antifuse technology. For example, they can be reconfigured several times. Particle Telescope (PATE) is a payload of the FORESAIL-1 satellite. The FPGA used in the PATE instrument is Microsemi ProASIC3EL A3PE3000L, which is Flash switch based. The FPGA is used for implementing the scientific data paths, which include pulse filtering, pulse height analysis and particle classification. FPGA is also responsible for communication to the satellites On-Board Computer (OBC), housekeeping and other tasks. Radiation can cause errors in FPGA configuration memory and also in the user data. These errors, known as bit-flips, can cause configuration changes and even permanent damage. Design techniques to mitigate these errors include Triple Modular Redundancy (TMR), guard gate filtering, safe Finite State Machine (FSM) coding, scrubbing, and other various techniques. In this thesis, these methods are presented and taken into account while developing the design for the data path. This thesis demonstrates how to develop a design for Flash-based FPGA that is launched to Low Earth Orbit (LEO). The developed design is the scientific data path for particle detection and particle energy determination. The data path was developed for PATE and it was tested with simulators and in laboratory.Kenttäohjelmoitavat porttipiirit (FPGA) soveltuvat hyvin satelliitteihin, joiden kehitykseen ei ole käytettävissä suurta budjettia. Suunnitteluprosessissa on kuitenkin otettava huomioon se, että säteily voi aiheuttaa virheitä FPGA piireissä. FPGA kyetään toteuttamaan käyttäen erilaisia teknologioita ja näillä teknologioilla on eri herkkyys säteilyyn. Nykyään Flash-pohjaiset FPGA:t ovat yhtä kestäviä, tai kestävämpiä kuin perinteisesti käytetyt antifuse teknologiat, kun kehitysvaiheessa implementoidaan säteilynsuojaus. Tämän lisäksi Flash teknologialla on myös muita etuja verrattaessa antifuse teknologiaan. Esimerkkinä mahdollisuus uudelleenkonfigurointiin. Hiukkasteleskooppi (PATE) on FORESAIL-1 satelliitin hyötykuorma. PATE instrumentissa käytetty FPGA on ProASIC3EL A3PE3000L ja se on Flash pohjainen. FPGA:ta käytetään tieteellisen datapolun toteuttamiseen, joka sisältää pulssin suodatuksen, pulssin korkeusanalyysin ja hiukkasten luokittelun. FPGA on vastuussa myös kommunikoinnista satelliitin päätietokoneelle (OBC), housekeeping datan keräyksestä ja muista instrumentille tarpeellisista operaatioista. Säteily voi aiheuttaa virheitä FPGA:n konfiguraatiomuistiin ja myös käyttäjädataan. Nämä virheet tunnetaan nimellä bit-flip ja ne voivat aiheuttaa konfiguraation muutoksia ja jopa pysyviä vaurioita. On olemassa erilaisia suunnittelutekniikoita, joita voidaan käyttää torjumaan näitä virheitä. Tässä työssä nämä metodit on esitelty ja niitä on hyödynnetty datapolun kehitystyössä. Tämä työ demonstroi miten Flash pohjaiselle FPGAlle kehitetään konfiguraatio, joka laukaistaan matalalle maan kiertoradalle. Konfiguraatio koostuu tieteellisestä datapolusta hiukkasten tunnistukseen ja niiden energioiden määrittelyyn. Datapolku kehitettiin PATE instrumentille ja sen toiminta testattiin simulaattoreilla, sekä laboratoriossa

2019 IEEE Sensors

Three-dimensional representations and maps are the key behind self-driving vehicles and many types of advanced autonomous robots. Localization and mapping algorithms can achieve much higher levels of accuracy with dense 3D point clouds. However, the cost of a multiple-channel three-dimensional lidar with a 360 degrees field of view is at least ten times the cost of an equivalent single-channel two-dimensional lidar. Therefore, while 3D lidars have become an essential component of self-driving vehicles, their cost has limited their integration and penetration within smaller robots. We present an FPGA-based 3D lidar built with multiple inexpensive RPLidar A1 2D lidars, which are rotated via a servo motor and their signals combined with an FPGA board. A C++ package for the Robot Operating System (ROS) has been written, which publishes a 3D point cloud. The mapping of points from the two-dimensional lidar output to the three-dimensional point cloud is done at the FPGA level, as well as continuous calibration of the motor speed and lidar orientation based on a built-in landmark recognition. This inexpensive design opens a wider range of possibilities for lower-end and smaller autonomous robots, which can be able to produce three-dimensional world representations. We demonstrate the possibilities of our design by mapping different environments.</p

Evidence of a causal effect of genetic tendency to gain muscle mass on uterine leiomyomata

Uterine leiomyomata (UL) are the most common tumours of the female genital tract and the primary cause of surgical removal of the uterus. Genetic factors contribute to UL susceptibility. To add understanding to the heritable genetic risk factors, we conduct a genome-wide association study (GWAS) of UL in up to 426,558 European women from FinnGen and a previous UL meta-GWAS. In addition to the 50 known UL loci, we identify 22 loci that have not been associated with UL in prior studies. UL-associated loci harbour genes enriched for development, growth, and cellular senescence. Of particular interest are the smooth muscle cell differentiation and proliferation-regulating genes functioning on the myocardin-cyclin dependent kinase inhibitor 1A pathway. Our results further suggest that genetic predisposition to increased fat-free mass may be causally related to higher UL risk, underscoring the involvement of altered muscle tissue biology in UL pathophysiology. Overall, our findings add to the understanding of the genetic pathways underlying UL, which may aid in developing novel therapeutics.Peer reviewe