Journal articles on the topic 'Design reference mission'
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Nieto-Peroy, Cristóbal, and M. Reza Emami. "CubeSat Mission: From Design to Operation." Applied Sciences 9, no. 15 (August 1, 2019): 3110. http://dx.doi.org/10.3390/app9153110.
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The current success rate of CubeSat missions, particularly for first-time developers, may discourage non-profit organizations to start new projects. CubeSat development teams may not be able to dedicate the resources that are necessary to maintain Quality Assurance as it is performed for the reliable conventional satellite projects. This paper discusses the structured life-cycle of a CubeSat project, using as a reference the authors’ recent experience of developing and operating a 2U CubeSat, called qbee50-LTU-OC, as part of the QB50 mission. This paper also provides a critique of some of the current poor practices and methodologies while carrying out CubeSat projects.
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Jia, Feida, Xiangyu Li, Zhuoxi Huo, and Dong Qiao. "Mission Design of an Aperture-Synthetic Interferometer System for Space-Based Exoplanet Exploration." Space: Science & Technology 2022 (February 17, 2022): 1–10. http://dx.doi.org/10.34133/2022/9835234.
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In recent years, exoplanet detection has become the technological frontier in the field of astronomy, because it provides evidence of the origin of life and the future human habitable exoplanet. Deploying several satellites to form an aperture-synthetic interferometer system in space may help discover “another Earth” via interferometry and midinfrared broadband spectroscopy. This paper analyzes a space-based exoplanet exploration mission in terms of the scientific background, mission profile, trajectory design, and orbital maintenance. First, the system architecture and working principle of the interferometer system are briefly introduced. Secondly, the mission orbit and corresponding transfer trajectories are discussed. The halo orbit near the Sun-Earth L2 (SEL2) orbit is chosen as the candidate mission orbit. The low-energy transfer via stable invariant manifold with multiple perigees is designed, and the proper launch windows are presented. A speed increment less than 10 m/s is imposed for each transfer to achieve the insertion of the halo orbit. Finally, the tangent targeting method (TTM) is applied for high-precision formation maintenance with the whole velocity increments of less than 5×10−4 m/s for each spacecraft when the error bound is 0.1 m. The overall fuel budget during the mission period is evaluated and compared. The design in this paper will provide technical support and reliable reference for future exoplanet exploration missions.
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Luo, Ya-zhong, and Li-ni Zhou. "Asteroid Rendezvous Mission Design Using Multiobjective Particle Swarm Optimization." Mathematical Problems in Engineering 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/823659.
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A new preliminary trajectory design method for asteroid rendezvous mission using multiobjective optimization techniques is proposed. This method can overcome the disadvantages of the widely employed Pork-Chop method. The multiobjective integrated launch window and multi-impulse transfer trajectory design model is formulated, which employes minimum-fuel cost and minimum-time transfer as two objective functions. The multiobjective particle swarm optimization (MOPSO) is employed to locate the Pareto solution. The optimization results of two different asteroid mission designs show that the proposed approach can effectively and efficiently demonstrate the relations among the mission characteristic parameters such as launch time, transfer time, propellant cost, and number of maneuvers, which will provide very useful reference for practical asteroid mission design. Compared with the PCP method, the proposed approach is demonstrated to be able to provide much more easily used results, obtain better propellant-optimal solutions, and have much better efficiency. The MOPSO shows a very competitive performance with respect to the NSGA-II and the SPEA-II; besides a proposed boundary constraint optimization strategy is testified to be able to improve its performance.
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Gaviraghi, Giorgio, and Pier Marzocca. "An Asteroid Starship Proposal." International Journal of Space Technology Management and Innovation 2, no. 2 (July 2012): 40–65. http://dx.doi.org/10.4018/ijstmi.2012070103.
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The instant asteroid starship is a reference plan for a manned interstellar mission, developed in the wake of the 100YSS program sponsored by DARPA and NASA. This plan consists of a full conceptual design that considers most of the requirements for a manned interstellar mission, including systems and subsystems, strategies, and motivation. For resource utilization, safety considerations, and immediate start of activities, a captured asteroid is engineered as a space settlement. In this article, basic aspects of this plan are summarized; the development is part of a larger effort, sponsored by the group Star Voyager, which should culminate in a reference starship design.
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WU, AN-MING, XIAOHUI XU, and WEI-TOU NI. "ORBIT DESIGN AND ANALYSIS FOR THE ASTROD MISSION CONCEPT." International Journal of Modern Physics D 09, no. 02 (April 2000): 201–14. http://dx.doi.org/10.1142/s0218271800000165.
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The ASTROD (Astrodynamical Space Test of Relativity using Optical Devices) mission concept is to conduct high-precision measurement of relativistic effects, better determination of the orbits of major asteroids and other solar system parameters, improvement in the measurement of [Formula: see text], measurement of solar angular momentum via Lense–Thirring effect, and the detection of low-frequency gravitational waves and solar oscillations in a single mission. It will be realized by placing a fleet of drag-free spacecraft in solar orbits together with an Earth reference system. Two spacecraft launched into separate solar orbits, as a simple implementation, can reach the opposite side of Sun after traveling about 2.5 years. In this paper, we describe the orbit design process for this simple implementation including the two-body model, initial velocity determination, and optimization consideration. Through fine tuning of the initial velocity, we can have the two spacecraft nearly return to the 2.5 years positions at 7.5 years mission time, which means that the ASTROD mission can have a second good chance to observe Shapiro time delay precisely and to measure the solar Lense–Thirring effect if the mission lasts over 7.5 years. We also calculate the light traveling time and the Shapiro time delay.
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Islam, Md Shofiqul, and Ibrahim M. Mehedi. "Landing Trajectory Generation and Energy Optimization for Unmanned Lunar Mission." Mathematical Problems in Engineering 2021 (July 1, 2021): 1–11. http://dx.doi.org/10.1155/2021/9902390.
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The moon is recognized as an important destination for space science and exploration. To find a satisfactory answer for the mystery of the universe and to make use of the lunar resources for the welfare of human beings, several space agencies are planning manned and unmanned missions on the moon. As a result, the concept of lunar vehicles has begun with an advanced descent scheme to execute a precise and safe landing on the surface of the moon. On the contrary, the energy budget is an important issue for any space mission. To reduce the cost of a space mission, it is necessary to design the vehicle trajectory based on optimized energy resources. Fuel is the main energy in a space mission. Therefore, a fuel-optimized energy generation technique is focused on this research. The design of an algorithm that generates a real-time trajectory for the descent and landing of a lunar probe is critical to ensuring a successful lunar landing mission. A scheme of dual-step trajectory generation for lunar descent is also investigated in this paper. In the algorithm developing process, the thrust-to-mass ratio is considered as a principle variable. Algorithm design along with mathematical modeling and simulation results are described in detail. In addition, the proposed method for generating reference trajectory profiles is also analyzed for fuel consumption and robustness.
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Allender, Elyse J., Csilla Orgel, Natasha V. Almeida, John Cook, Jessica J. Ende, Oscar Kamps, Sara Mazrouei, Thomas J. Slezak, Assi-Johanna Soini, and David A. Kring. "Traverses for the ISECG-GER design reference mission for humans on the lunar surface." Advances in Space Research 63, no. 1 (January 2019): 692–727. http://dx.doi.org/10.1016/j.asr.2018.08.032.
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Weber, William Joseph, Daniele Bortoluzzi, Paolo Bosetti, Gabriel Consolini, Rita Dolesi, and Stefano Vitale. "Application of LISA Gravitational Reference Sensor Hardware to Future Intersatellite Geodesy Missions." Remote Sensing 14, no. 13 (June 27, 2022): 3092. http://dx.doi.org/10.3390/rs14133092.
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Like gravitational wave detection, inter-spacecraft geodesy is a measurement of gravitational tidal accelerations deforming a constellation of two or more orbiting reference test masses (TM). The LISA TM system requires TM in free fall with residual stray accelerations approaching the fm/s2/Hz1/2 level in the mHz band, as demonstrated in the LISA Pathfinder “Einstein’s geodesic explorer” mission. Current geodesy missions are limited by accelerometers with 100 pm/s2/Hz1/2 level, due to intrinsic design limitations, as well as the challenging low Earth orbit environment and operating conditions. A reduction in the TM acceleration noise could lead to an important improvement in the scientific return of future geodesy missions focusing on mass change, especially in a scenario with multiple pairs of geodesy satellites. We present here a preliminary assessment of how the LISA TM system, known as the “gravitational reference sensor” (GRS), could be adapted for use in future geodesy missions aiming at residual TM accelerations noise at the pm/s2/Hz1/2 level, addressing the major design issues and performance limitations. We find that such a performance is possible in a geodesy GRS that is simpler and smaller than that used for LISA, with a lighter, sub-kg TM and gaps reduced from 4 mm to less than 1 mm. Acceleration noise performance limitations will likely be closely tied to the required levels of applied actuation forces on the TM.
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Mao, Yuhao, Wenhan Dong, Jiahai Zhu, Ri Liu, and Jinyong Chang. "Influence of the ground effect on airdrop mission performance analysis." International Journal of Advanced Robotic Systems 15, no. 1 (January 1, 2018): 172988141875847. http://dx.doi.org/10.1177/1729881418758473.
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Aimed at determining the ground effect’s influence on the process of ultralow-altitude airdrop, this article studies the corresponding changes in aerodynamic characteristics caused by the ground effect. Through analyzing the longitudinal long- and short-period modes and the lateral mode, this work evaluates the impact that the ground effect has on the level-off and the traction stages during an airdrop mission, with reference to corresponding flight quality standards. Accordingly, these findings provide a reference for the design of flight control regarding airdrop capabilities and support a theory for corresponding ground experiments.
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Dong, J., Z. Sun, W. Rao, Y. Jia, L. Meng, C. Wang, and B. Chen. "MISSION PROFILE AND DESIGN CHALLENGES FOR MARS LANDING EXPLORATION." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W1 (July 25, 2017): 35–39. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w1-35-2017.
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An orbiter and a descent module will be delivered to Mars in the Chinese first Mars exploration mission. The descent module is composed of a landing platform and a rover. The module will be released into the atmosphere by the orbiter and make a controlled landing on Martian surface. After landing, the rover will egress from the platform to start its science mission. The rover payloads mainly include the subsurface radar, terrain camera, multispectral camera, magnetometer, anemometer to achieve the scientific investigation of the terrain, soil characteristics, material composition, magnetic field, atmosphere, etc. The landing process is divided into three phases (entry phase, parachute descent phase and powered descent phase), which are full of risks. There exit lots of indefinite parameters and design constrain to affect the selection of the landing sites and phase switch (mortaring the parachute, separating the heat shield and cutting off the parachute). A number of new technologies (disk-gap-band parachute, guidance and navigation, etc.) need to be developed. Mars and Earth have gravity and atmosphere conditions that are significantly different from one another. Meaningful environmental conditions cannot be recreated terrestrially on earth. A full-scale flight validation on earth is difficult. Therefore the end-to-end simulation and some critical subsystem test must be considered instead. The challenges above and the corresponding design solutions are introduced in this paper, which can provide reference for the Mars exploration mission.
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Theilliol, Didier, Cédric Join, and Youmin Zhang. "Actuator Fault Tolerant Control Design Based on a Reconfigurable Reference Input." International Journal of Applied Mathematics and Computer Science 18, no. 4 (December 1, 2008): 553–60. http://dx.doi.org/10.2478/v10006-008-0048-1.
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Actuator Fault Tolerant Control Design Based on a Reconfigurable Reference InputThe prospective work reported in this paper explores a new approach to enhance the performance of an active fault tolerant control system. The proposed technique is based on a modified recovery/trajectory control system in which a reconfigurable reference input is considered when performance degradation occurs in the system due to faults in actuator dynamics. An added value of this work is to reduce the energy spent to achieve the desired closed-loop performance. This work is justified by the need of maintaining a reliable system in a dynamical way in order to achieve a mission by an autonomous system, e.g., a launcher, a satellite, a submarine, etc. The effectiveness is illustrated using a three-tank system for slowly varying reference inputs corrupted by actuators faults.
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Feng, Lin Ping, Zuo E. Fan, and You Gen Zhang. "Design of Guidance Law with Impact Angle and Impact Time Constraints." Advanced Materials Research 945-949 (June 2014): 1493–99. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.1493.
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In order to achieve the tactical mission of cooperative attack for multi-missiles, in a predetermined direction at a predetermined time, this paper studies the design of guidance law with impact angle and impact time constraints. Firstly, using the optimal control theory, the optimal guidance law is designed to control the impact angle, based the relative motion between missile and target. Then the state feedback guidance law is designed to control the arrival impact time, with the application of feedback linearization control theory. Finally, reference the design idea of two-stage guidance system, the anti-ship missile use two different guidance laws in the process of attacking the target. During the first stage, the state feedback guidance law is used to accurately control the impact time and coarsely control the impact angle. During the second stage, the optimal guidance law is used to accurately control the impact angle. And the correctness and effectiveness of the design method is verified by simulation.
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Lombardo, Marco, Marco Zannoni, Igor Gai, Luis Gomez Casajus, Edoardo Gramigna, Riccardo Lasagni Manghi, Paolo Tortora, et al. "Design and Analysis of the Cis-Lunar Navigation for the ArgoMoon CubeSat Mission." Aerospace 9, no. 11 (October 27, 2022): 659. http://dx.doi.org/10.3390/aerospace9110659.
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In the framework of the Artemis-1 mission, 10 CubeSats will be released, including the 6U CubeSat ArgoMoon, built by the Italian company Argotec and coordinated by the Italian Space Agency. The primary goal of ArgoMoon is to capture images of the Interim Cryogenic Propulsion Stage. Then, ArgoMoon will be placed into a highly elliptical orbit around the Earth with several encounters with the Moon. In this phase, the navigation process will require a precise Orbit Determination (OD) and a Flight Path Control (FPC) to satisfy the navigation requirements. The OD will estimate the spacecraft trajectory using ground-based radiometric observables. The FPC is based on an optimal control strategy designed to reduce the dispersion with respect to the reference trajectory and minimize the total ΔV. A linear approach was used to determine the optimal targets and the number and location of the orbital maneuvers. A covariance analysis was performed to assess the expected OD performance and its robustness. The analysis results show that the reference translunar trajectory can be successfully flown and the navigation performance is strongly dependent on the uncertainties of the ArgoMoon’s Propulsion Subsystem and of the orbit injection.
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Briottet, Xavier. "BIODIVERSITY – A new space mission to monitor Earth ecosystems at fine scale." Revue Française de Photogrammétrie et de Télédétection 224, no. 1 (December 22, 2022): 33–58. http://dx.doi.org/10.52638/rfpt.2022.568.
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Imaging spectroscopy has demonstrated its interest in characterizing the biochemical, biophysical and structural properties of vegetation, natural and agricultural soils, as well as artificial surfaces. Following the Hyperion mission, new space missions have emerged (PRISMA, EnMap), or are under study (CHIME, SBG). However, one of their main limitations lies in their spatial resolution that induces a large number of mixed pixels reducing their potential for discrimination for very heterogeneous areas. The BIODIVERSITY mission aims to complement these space missions with better GSD acquisitions (typically 8-10 m) with a 5-day revisit on targeted reference sites with identified and well-located characteristics. It will thus make it possible, in particular, to answer two scientific issues that will design the instrument. The first issue concerns the spatial and temporal distribution of vegetation traits in species assemblages; these traits are associated with the resilience of terrestrial ecosystems, anthropogenic influences, and the biodiversity of ecosystems in terms of species composition and assemblages. The second issue relates to improving our knowledge of coastal areas and inland waters in terms of biodiversity, water quality and bathymetry, in order to assess the impact of human activity on their ecosytems. The scientific challenges as well as the user requirements for such a mission are presented for each application.
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Li, Yang-Rui, and Chao-Chung Peng. "Super-Twisting Sliding Mode Control Law Design for Attitude Tracking Task of a Spacecraft via Reaction Wheels." Mathematical Problems in Engineering 2021 (March 15, 2021): 1–13. http://dx.doi.org/10.1155/2021/6644033.
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The attitude control has been recognized as one of the most important research topics for spacecraft. If the desired attitude trajectory cannot be tracked precisely, it may cause mission failures. In the real space mission environment, the unknown external perturbations, for example, atmospheric drag and solar radiation, should be taken into consideration. Such external perturbations could deviate the precision of the spacecraft orientation and thereby lead to a mission failure. Therefore, in this paper, a quaternion-based super-twisting sliding mode robust control law for the spacecraft attitude tracking is developed. The finite time stability based on the formulation of the linear matrix inequality (LMI) is also provided. To avoid losing the control degree of freedom due to the certain actuator fault, a redundant reaction wheels configuration is adopted. The actuators distribution associated force distribution matrix (FDM) is analyzed in detail. Finally, the reference tangent-normal-binormal (TNB) command generation strategy is implemented for simulating the scenario of the space mission. Finally, the simulation results reveal that the spacecraft can achieve the desired attitude trajectory tracking demands in the presence of the time-varying external disturbances.
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Ali, F., K. Tzanidakis, I. Goulos, V. Pachidis, and R. d’Ippolito. "Multidisciplinary design and optimisation of conceptual rotorcraft powerplants for operational performance and environmental impact." Aeronautical Journal 119, no. 1217 (July 2015): 891–914. http://dx.doi.org/10.1017/s0001924000010976.
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AbstractThis paper demonstrates the application of an integrated rotorcraft multidisciplinary design and optimisation framework, deployed for the purpose of preliminary design and assessment of optimum regenerative powerplant configurations for rotorcraft applications. The proposed approach comprises a wide-range of individual modelling theories applicable to rotorcraft flight dynamics, gas turbine engine performance and weight estimation as well as a physics-based stirred reactor model, for the rapid estimation of various gas turbine gaseous emissions. A single-objective Particle Swarm Optimiser is coupled with the aforementioned rotorcraft design framework. The overall methodology is deployed for the design and optimisation of a reference multipurpose Twin-Engine-Light civil rotorcraft, modelled after the Bo105 helicopter, which employs two Rolls-Royce Allison 250-C20B turboshaft engines. Through the implementation of a single-objective optimisation strategy, notionally based optimum engine design configurations are acquired in terms of engine weight, mission fuel burn and mission gaseous emissions inventory at constant technology level.The acquired optimum regenerative engine configurations are subsequently deployed for the design of conceptual rotorcraft regenerative engine configurations, targeting improved mission fuel economy, enhanced payload-range capability as well as overall environmental impact, while maintaining the respective rotorcraft airworthiness requirements. The proposed methodology essentially constitutes as an enabler for designing rotorcraft powerplants within realistic, three-dimensional operations and towards realising their associated design trade-offs at mission level.
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Banda, Francesco, Davide Giudici, Thuy Le Le Toan, Mauro Mariotti Mariotti d’Alessandro, Kostas Papathanassiou, Shaun Quegan, Guido Riembauer, et al. "The BIOMASS Level 2 Prototype Processor: Design and Experimental Results of Above-Ground Biomass Estimation." Remote Sensing 12, no. 6 (March 19, 2020): 985. http://dx.doi.org/10.3390/rs12060985.
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BIOMASS is ESA’s seventh Earth Explorer mission, scheduled for launch in 2022. The satellite will be the first P-band SAR sensor in space and will be operated in fully polarimetric interferometric and tomographic modes. The mission aim is to map forest above-ground biomass (AGB), forest height (FH) and severe forest disturbance (FD) globally with a particular focus on tropical forests. This paper presents the algorithms developed to estimate these biophysical parameters from the BIOMASS level 1 SAR measurements and their implementation in the BIOMASS level 2 prototype processor with a focus on the AGB product. The AGB product retrieval uses a physically-based inversion model, using ground-canceled level 1 data as input. The FH product retrieval applies a classical PolInSAR inversion, based on the Random Volume over Ground Model (RVOG). The FD product will provide an indication of where significant changes occurred within the forest, based on the statistical properties of SAR data. We test the AGB retrieval using modified airborne P-Band data from the AfriSAR and TropiSAR campaigns together with reference data from LiDAR-based AGB maps and plot-based ground measurements. For AGB estimation based on data from a single heading, comparison with reference data yields relative Root Mean Square Difference (RMSD) values mostly between 20% and 30%. Combining different headings in the estimation process significantly improves the AGB retrieval to slightly less than 20%. The experimental results indicate that the implemented retrieval scheme provides robust results that are within mission requirements.
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Montesinos, Carlos A., Radina Khalid, Octav Cristea, Joel S. Greenberger, Michael W. Epperly, Jennifer A. Lemon, Douglas R. Boreham, et al. "Space Radiation Protection Countermeasures in Microgravity and Planetary Exploration." Life 11, no. 8 (August 14, 2021): 829. http://dx.doi.org/10.3390/life11080829.
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Background: Space radiation is one of the principal environmental factors limiting the human tolerance for space travel, and therefore a primary risk in need of mitigation strategies to enable crewed exploration of the solar system. Methods: We summarize the current state of knowledge regarding potential means to reduce the biological effects of space radiation. New countermeasure strategies for exploration-class missions are proposed, based on recent advances in nutrition, pharmacologic, and immune science. Results: Radiation protection can be categorized into (1) exposure-limiting: shielding and mission duration; (2) countermeasures: radioprotectors, radiomodulators, radiomitigators, and immune-modulation, and; (3) treatment and supportive care for the effects of radiation. Vehicle and mission design can augment the overall exposure. Testing in terrestrial laboratories and earth-based exposure facilities, as well as on the International Space Station (ISS), has demonstrated that dietary and pharmacologic countermeasures can be safe and effective. Immune system modulators are less robustly tested but show promise. Therapies for radiation prodromal syndrome may include pharmacologic agents; and autologous marrow for acute radiation syndrome (ARS). Conclusions: Current radiation protection technology is not yet optimized, but nevertheless offers substantial protection to crews based on Lunar or Mars design reference missions. With additional research and human testing, the space radiation risk can be further mitigated to allow for long-duration exploration of the solar system.
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Latachi, Ibtissam, Tajjeeddine Rachidi, Mohammed Karim, and Ahmed Hanafi. "Reusable and Reliable Flight-Control Software for a Fail-Safe and Cost-Efficient Cubesat Mission: Design and Implementation." Aerospace 7, no. 10 (October 10, 2020): 146. http://dx.doi.org/10.3390/aerospace7100146.
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While there is no rigorous framework to develop nanosatellites flight software, this manuscript aimed to explore and establish processes to design a reliable and reusable flight software architecture for cost-efficient student Cubesat missions such as Masat-1. Masat-1 is a 1Unit CubeSat, developed using a systems engineering approach, off-the-shelf components and open-source software tools. It was our aim to use it as a test-bed platform and as an initial reference for Cubesat flight software development in Morocco. The command and data handling system chosen for Masat-1 is a system-on-module-embedded computer running freeRTOS. A real-time operating system was used in order to simplify the real-time onboard management. To ensure software design reliability, modularity, reusability and extensibility, our solution follows a layered service oriented architectural pattern, and it is based on a finite state machine in the application layer to execute the mission functionalities in a deterministic manner. Moreover, a client-server model was elected to ensure the inter-process communication and resources access while using uniform APIs to enhance cross-platform data exchange. A hierarchical fault tolerance architecture was also implemented after a systematic assessment of the Masat-1 mission risks using reliability block diagrams (RBDs) and functional failure mode, effect and criticality analysis (FMECA).
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Borges, Renato Alves, Andrea Cristina dos Santos, William Reis Silva, Leonardo Aguayo, Geovany Araújo Borges, Marcelo Monte Karam, Rogério Baptista de Sousa, et al. "The AlfaCrux CubeSat Mission Description and Early Results." Applied Sciences 12, no. 19 (September 28, 2022): 9764. http://dx.doi.org/10.3390/app12199764.
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On 1 April 2022, the AlfaCrux CubeSat was launched by the Falcon 9 Transporter-4 mission, the fourth SpaceX dedicated smallsat rideshare program mission, from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida into a Sun-synchronous orbit at 500 km. AlfaCrux is an amateur radio and educational mission to provide learning and scientific benefits in the context of small satellite missions. It is an opportunity for theoretical and practical learning about the technical management, systems design, communication, orbital mechanics, development, integration, and operation of small satellites. The AlfaCrux payload, a software-defined radio hardware, is responsible for two main services, which are a digital packet repeater and a store-and-forward system. In the ground segment, a cloud-computing-based command and control station has been developed, together with an open access online platform to access and visualize the main information of the AlfaCrux telemetry and user data and experiments. It also becomes an in-orbit database reference to be used for different studies concerned with, for instance, radio propagation, attitude reconstruction, data-driven calibration algorithms for satellite sensors, among others. In this context, this paper describes the AlfaCrux mission, its main subsystems, and the achievements obtained in the early orbit phase. Scientific and engineering assessments conducted with the spacecraft operations to tackle unexpected behaviors in the ground station and also to better understand the space environment are also presented and discussed.
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Nugroho, Gesang, and Dicky Dectaviansyah. "Design, manufacture and performance analysis of an automatic antenna tracker for an unmanned aerial vehicle (UAV)." Journal of Mechatronics, Electrical Power, and Vehicular Technology 9, no. 1 (July 31, 2018): 32. http://dx.doi.org/10.14203/j.mev.2018.v9.32-40.
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In conducting a disaster monitoring mission, an unmanned aerial vehicle (UAV) has to travel a long distance to cover the region that is hited by a disaster. In the monitoring mission, Air Data and Attitude Heading Reference System (ADAHRS) data are very important to always be displayed on the ground control station (GCS). Unfortunately, the area of monitoring mission is very wide, whereas the usage of an omnidirectional antenna in the disaster monitoring mission is limited to the UAV maximum range. Therefore, a high gain directional antenna is needed. However, the directional antenna has a disadvantage of always being directed to the target. To solve this problem, antenna tracker is made to track the UAV continuously so that the directional antenna can always be directed to the flying UAV. An antenna tracker using a 32-bit microcontroller and GPS with two degrees-of-freedom was developed. It is able to move 360 degrees on azimuth axis (yaw) and 90 degrees on elevation axis (pitch). Meanwhile, the directional antenna is three elements yagi type with a radiation capability of 6 dBi. By using the antenna tracker, larger UAV range was obtained and the connection between the UAV and the GCS could always be maintained with a minimum fluctuation of RSSI signal, compared to those without using antenna tracker.
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Noor, Ahmed K., Robert Zubrin, and Douglas Stanley. "A Step Closer to Mars." Mechanical Engineering 128, no. 11 (November 1, 2006): 25–30. http://dx.doi.org/10.1115/1.2006-nov-1.
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This paper describes the various developments of robust systems for human mars mission. The engineering of highly reliable, robust systems for those human space missions, along with the creation of a livable, artificial environment on Mars, will provide a new arena for the innovation of future technologies, allowing scientific progress and creating economic growth. Studies of human Mars missions have been conducted in the last two decades by NASA, other space agencies, and non-government groups, including the Mars Society. NASA has developed a series of design reference missions to serve as guideposts toward sending a human crew to Mars and to provide a basis for comparing different approaches and criteria. In order to achieve Mars orbit insertion and descent to the surface, rather large accelerations are required, which if implemented through chemical propulsion, require very large propellant masses. The rich carbon supply on Mars also suggests a possibility of local production of such essentials as plastics, lubricants, and synthetic fabrics.
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Fajardo, Isai, Aleksander Lidtke, Sidi Bendoukha, Jesus Gonzalez-Llorente, Rafael Rodríguez, Rigoberto Morales, Dmytro Faizullin, et al. "Design, Implementation, and Operation of a Small Satellite Mission to Explore the Space Weather Effects in LEO." Aerospace 6, no. 10 (September 27, 2019): 108. http://dx.doi.org/10.3390/aerospace6100108.
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Ten-Koh is a 23.5 kg, low-cost satellite developed to conduct space environment effects research in low-Earth orbit (LEO). Ten-Koh was developed primarily by students of the Kyushu Institute of Technology (Kyutech) and launched on 29 October 2018 on-board HII-A rocket F40, as a piggyback payload of JAXA’s Greenhouse gas Observing Satellite (GOSAT-2). The satellite carries a double Langmuir probe, CMOS-based particle detectors and a Liulin spectrometer as main payloads. This paper reviews the design of the mission, specifies the exact hardware used, and outlines the implementation and operation phases of the project. This work is intended as a reference that other aspiring satellite developers may use to increase their chances of success. Such a reference is expected to be particularly useful to other university teams, which will likely face the same challenges as the Ten-Koh team at Kyutech. Various on-orbit failures of the satellite are also discussed here in order to help avoid them in future small spacecraft. Applicability of small satellites to conduct space-weather research is also illustrated on the Ten-Koh example, which carried out simultaneous measurements with JAXA’s ARASE satellite.
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Lucas Martínez, Néstor, José-Fernán Martínez-Ortega, Pedro Castillejo, and Victoria Beltrán Martínez. "Survey of Mission Planning and Management Architectures for Underwater Cooperative Robotics Operations." Applied Sciences 10, no. 3 (February 6, 2020): 1086. http://dx.doi.org/10.3390/app10031086.
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Almost every research project that focuses on the cooperation of autonomous robots for underwater operations designs their own architectures. As a result, most of these architectures are tightly coupled with the available robots/vehicles for their respective developments, and therefore the mission plan and management is done using an ad-hoc solution. Typically, this solution is tightly coupled to just one underwater autonomous vehicle (AUV), or a restricted set of them selected for the specific project. However, as the use of AUVs for underwater operations increases, there is the need to identify some commonalities and weaknesses of these architectures, specifically in relation to mission planning and management. In this paper, we review a selected number of architectures and frameworks that in one way or another make use of different approaches to mission planning and management. Most of the selected works were developed for underwater operations. Still, we have included some other architectures and frameworks from other domains that can be of interest for the survey. The explored works have been assessed using selected features related to mission planning and management, considering that underwater operations are performed in an uncertain and unreliable environment, and where unexpected events are not strange. Furthermore, we have identified and highlighted some potential challenges for the design and implementation of mission managers. This provides a reference point for the development of a mission manager component to be integrated in architectures for cooperative robotics in underwater operations, and it can serve for the same purposes in other domains of application.
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Spada, Daniele, Paolo Molinari, Walter Bertoldi, Alfonso Vitti, and Guido Zolezzi. "Multi-Temporal Image Analysis for Fluvial Morphological Characterization with Application to Albanian Rivers." ISPRS International Journal of Geo-Information 7, no. 8 (August 3, 2018): 314. http://dx.doi.org/10.3390/ijgi7080314.
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A procedure for the characterization of the temporal evolution of river morphology is presented. Wet and active river channels are obtained from the processing of imagery datasets. Information about channel widths and active channel surface subdivision in water, vegetation and gravel coverage classes are evaluated along with channel centerline lengths and sinuosity indices. The analysis is carried out on a series of optical remotely-sensed imagery acquired by different satellite missions during the time period between 1968 and 2017. Data from the CORONA, LANDSAT and Sentinel-2 missions were considered. Besides satellite imagery, a digital elevation model and aerial ortho-photos were also used. The procedure was applied to three, highly dynamic, Albanian rivers: Shkumbin, Seman and Vjosë, showing a high potential for application in contexts with limitations in ground data availability. The results of the procedure were assessed against reference data produced by means of expert interpretation of a reference set of river reaches. The results differ from reference values by just a few percentage points (<6%). The time evolution of hydromorphological parameters is well characterized, and the results support the design of future studies aimed at the understanding of the relations between climatic and anthropogenic controls and the response of river morphological trajectories. Moreover, the high spatial and temporal resolution of the Sentinel-2 mission motivates the development of an automatic monitoring system based on a rolling application of the defined procedure.
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Makadia, Rahil, Sabina D. Raducan, Eugene G. Fahnestock, and Siegfried Eggl. "Heliocentric Effects of the DART Mission on the (65803) Didymos Binary Asteroid System." Planetary Science Journal 3, no. 8 (August 1, 2022): 184. http://dx.doi.org/10.3847/psj/ac7de7.
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Abstract The Double Asteroid Redirect Test (DART) is NASA’s first kinetic impact–based asteroid deflection mission. The DART spacecraft will act as a projectile during a hypervelocity impact on Dimorphos, the secondary asteroid in the (65803) Didymos binary system, and alter its mutual orbital period. The initial momentum transfer between the DART spacecraft and Dimorphos is enhanced by the ejecta flung off the surface of Dimorphos. This exchange is characterized within the system by the momentum enhancement parameter, β, and on a heliocentric level by its counterpart, β ⊙. The relationship between β and the physical characteristics of Dimorphos is discussed here. A nominal set of Dimorphos physical parameters from the design reference asteroid and impact circumstances from the design reference mission are used to initialize the ejecta particles for dynamical propagation. The results of this propagation are translated into a gradual momentum transfer onto the Didymos system barycenter. A high-quality solar system propagator is then used to produce precise estimates of the post-DART encounters between Didymos and Earth by generating updated close approach maps. Results show that even for an unexpectedly high β ⊙, a collision between the Didymos system and Earth is practically excluded in the foreseeable future. A small but significant difference is found in modeling the overall momentum transfer when individual ejecta particles escape the Didymos system, as opposed to imparting the ejecta momentum as a single impulse at impact. This difference has implications for future asteroid deflection campaigns, especially when it is necessary to steer asteroids away from gravitational keyholes.
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Viola, Nicole, Pietro Roncioni, Oscar Gori, and Roberta Fusaro. "Aerodynamic Characterization of Hypersonic Transportation Systems and Its Impact on Mission Analysis." Energies 14, no. 12 (June 16, 2021): 3580. http://dx.doi.org/10.3390/en14123580.
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This paper aims to provide technical insights on the aerodynamic characterization activities performed in the field of the H2020 STRATOFLY project, for the Mach 8 waverider reference configuration. Considering the complexity of the configuration to be analyzed at conceptual/preliminary design stage, a build-up approach has been adopted. The complexity of the aerodynamic model increases incrementally, from the clean external configuration up to the complete configuration, including propulsion systems elements and flight control surfaces. At each step, the aerodynamic analysis is complemented with detailed mission analysis, in which the different versions of the aerodynamic databases are used as input for the trajectory simulation. eventually, once the contribution to the aerodynamic characterization of flight control surfaces is evaluated, stability and trim analysis is carried out. The comparison of the results obtained through the different mission analysis campaigns clearly shows that the accuracy of aerodynamic characterization may determine the feasibility or unfeasibility of a mission concept.
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Moëns, Frédéric. "A Fast Aerodynamic Model for Aircraft Multidisciplinary Design and Optimization Process." Aerospace 10, no. 1 (December 22, 2022): 7. http://dx.doi.org/10.3390/aerospace10010007.
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A multidisciplinary design analysis and optimization process is developed at ONERA for the design of tube and wing and blended wing–body aircraft configurations. This process is composed of different disciplinary modules (geometry, propulsion, aerodynamics, structure, handling qualities and flight mission), and the overall process considers different fidelity levels for these modules at each step of the design process. This article describes the low-fidelity aerodynamic module used during the preliminary design optimization process. Analytical formulations retained for lift and drag components are presented in the first part. Then, the performances estimated by the aerodynamic module on some reference configurations are compared with both numerical and experimental data, showing a quite good agreement for both tube and wing and blended wing–body configurations not only for global performance but also for individual drag components.
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Wang, Zian, Zheng Gong, Shengchen Mao, Zan Zhou, Yongliang Chen, and Tongren Zhang. "Short Takeoff and Landing Strategy for Small-Scale Thrust-Vectoring Vertical/Short Takeoff and Landing Vehicles." Applied Sciences 12, no. 17 (August 24, 2022): 8449. http://dx.doi.org/10.3390/app12178449.
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This work provides a feasible solution to the shipborne short landing problem for thrust-vectoring V/STOL vehicles. The short takeoff and shipborne rolling vertical landing strategy was designed in this work. First, the strategy design reference was established by flying performance and mission requirements, including the short takeoff and landing performance, deceleration performance, trajectory stability, velocity stability, and conversion corridor, using attainable equilibrium set methods based on the six dimensions of freedom model of the study object. Then, a piecewise short takeoff landing strategy was designed based on the references, together with a nonlinear dynamic inverse-based control designed frame for strategy execution. Finally, the hardware-in-loop Monte-Carlo simulation was implemented for the strategy feasibility verification. The proposed short takeoff and landing strategy satisfies the shipborne short takeoff and landing mission requirements. The short takeoff shortens the taxiing distance by 40% compared to a normal takeoff. With a 20% perturbance on all model parameters, the touchdown speed can be controlled to 14 ± 1 m/s, and the landing point position can be constrained inside a 5 m radius circle with almost zero lateral displacements.
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Xu, Xin, Mao Mao Sun, and Jun Jiang. "A Novel High Frequency Isolated Feedback Generator with SOI Process." Applied Mechanics and Materials 462-463 (November 2013): 627–31. http://dx.doi.org/10.4028/www.scientific.net/amm.462-463.627.
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This paper mentioned the design of an isolated feedback generator with SOI process. This generator adopts 40V SOI technology and it integrates reference, high frequency oscillator, error amplifier and modulator, meanwhile this generator predigests the mission of designing for the closed loop feedback of the switching power supply which types are the isolated and primary controlled. Along with the developing of the power conversion, this circuit is specially designed for high reliability, high capability and anti-radicalization applications.
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Høg, E. "A New Era of Global Astrometry. II: A 10 Microarcsecond Mission." Symposium - International Astronomical Union 166 (1995): 317–22. http://dx.doi.org/10.1017/s0074180900228271.
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A ground-based project for a small telescope about 20 cm aperture is proposed. It would be able to obtain 500 million astrometric observations per year of all stars between V=7 and 18 mag, based on the Hipparcos-Tycho reference net of one million stars. In addition, V and I magnitudes for all stars from V=7 to 17 mag would be obtained. — A new space mission is proposed, capable of obtaining 10 microarcsecond (μas) precision for parallaxes and proper motions of stars of V = 11 mag, and a precision of 0.5 millimagnitude (mmag) for intermediate-band photometry. The mission is here called Roemer Plus (or Roemer+) and the design is derived from Hipparcos and Roemer, but a larger telescope aperture and high-precision metrology is applied. At magnitude V = 20 a precision of 1.0 milliarcsecond (mas) would be achieved.
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Ali, F., I. Goulos, and V. Pachidis. "An integrated methodology to assess the operational and environmental performance of a conceptual regenerative helicopter." Aeronautical Journal 119, no. 1211 (January 2015): 67–90. http://dx.doi.org/10.1017/s0001924000010253.
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AbstractThis paper aims to present an integrated multidisciplinary simulation framework, deployed for the comprehensive assessment of combined helicopter–powerplant systems at mission level. Analytical evaluations of existing and conceptual regenerative engine designs are carried out in terms of operational performance and environmental impact. The proposed methodology comprises a wide-range of individual modeling theories applicable to helicopter flight dynamics, gas turbine engine performance as well as a novel, physics-based, stirred reactor model for the rapid estimation of various helicopter emissions species. The overall methodology has been deployed to conduct a preliminary trade-off study for a reference simple cycle and conceptual regenerative twin-engine light helicopter, modeled after the Airbus Helicopters Bo105 configuration, simulated under the representative mission scenarios. Extensive comparisons are carried out and presented for the aforementioned helicopters at both engine and mission level, along with general flight performance charts including the payload-range diagram. The acquired results from the design trade-off study suggest that the conceptual regenerative helicopter can offer significant improvement in the payload-range capability, while simultaneously maintaining the required airworthiness requirements. Furthermore, it has been quantified through the implementation of a representative case study that, while the regenerative configuration can enhance the mission range and payload capabilities of the helicopter, it may have a detrimental effect on the mission emissions inventory, specifically for NOx(Nitrogen Oxides). This may impose a trade-off between the fuel economy and environmental performance of the helicopter. The proposed methodology can effectively be regarded as an enabling technology for the comprehensive assessment of conventional and conceptual helicopter-powerplant systems, in terms of operational performance and environmental impact as well as towards the quantification of their associated trade-offs at mission level.
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Zheng, Hongxing, Xin Liu, Junhui Wu, Yiyun Man, Xibao Xu, and Jifeng Guo. "The on-orbit mission analysis of OTV based on DoDAF." Aircraft Engineering and Aerospace Technology 93, no. 6 (July 26, 2021): 937–45. http://dx.doi.org/10.1108/aeat-03-2020-0062.
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Purpose The purpose of this paper is to improve the efficiency of on-orbit operations through the top-level task design based on DoDAF. Based on the existing upper stage rocket technology, orbit transfer vehicles (OTVs) have developed rapidly in recent years. However, the lack of decision guidance based on overall task analysis requires integrating top-level analysis and bottom-level execution to achieve the smooth development of full-process tasks. Design/methodology/approach Using the Department of Defense Architecture Framework (DoDAF) as a reference, this paper performs the top-level mission analysis modeling of the on-orbit rendezvous and capture of the OTV. Moreover, the typical operational view products are obtained, and the cooperative relations among the mission requirements, the system requirements, and the functional requirements are also analyzed. Findings The results show that the attitude of the OTV changes violently during the maneuver and rendezvous phases. In addition, the view products can be optimized based on the results. Originality/value The proposed DoDAF-based on-orbit task integration analysis method achieves the effective fusion of high-level analysis and bottom-level execution of OTV on-orbit rendezvous and capture task through the top-level task modeling, operation view generation and task relationship analysis. According to the requirements and constraints of the on-orbit rendezvous and capture task, the control instructions of the vehicle are efficiently generated under the DoDAF framework.
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Casas, Francisco J., Enrique Martínez-González, Juan Bermejo-Ballesteros, Sergio García, Javier Cubas, Patricio Vielva, Rita B. Barreiro, and Angel Sanz. "L2-CalSat: A Calibration Satellite for Ultra-Sensitive CMB Polarization Space Missions." Sensors 21, no. 10 (May 12, 2021): 3361. http://dx.doi.org/10.3390/s21103361.
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In this work, the use of a calibration satellite (L2-CalSat) flying in formation with a Cosmic Microwave Background (CMB) polarization mission in an orbit located at the second Lagrange point, is proposed. The new generation of CMB telescopes are expected to reach unprecedented levels of sensitivity to allow a very precise measurement of the B-mode of polarization, the curl-like polarization component expected from gravitational waves coming from Starobinski inflationary models. Due to the CMB polarized signal weakness, the instruments must be subjected to very precise calibration processes before and after launching. Celestial sources are often used as external references for calibration after launch, but these sources are not perfectly characterized. As a baseline option, L2-CalSat is based on the CubeSat standard and serves as a perfectly known source of a reference signal to reduce polarization measurements uncertainty. A preliminary design of L2-CalSat is described and, according to the scanning strategy followed by the telescope, the influence of the relative position between the spacecrafts in the calibration process is studied. This new calibration element will have a huge impact on the performance of CMB space missions, providing a significant improvement in the measurements accuracy without requiring new and costly technological developments.
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Samar, R., M. Zamurad Shah, and M. Nzar. "Lateral Control Implementation for an Unmanned Aerial Vehicle." ISRN Aerospace Engineering 2013 (June 11, 2013): 1–14. http://dx.doi.org/10.1155/2013/905865.
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This paper presents practical aspects of guidance and control design for UAV and its flight test results. The paper focuses on the lateral-directional control and guidance aspects. An introduction to the mission and guidance problem is given first. Waypoints for straight and turning flight paths are defined. Computation of various flight path parameters is discussed, including formulae for real-time calculation of down-range (distance travelled along the desired track), cross-track deviation, and heading error of the vehicle; these are then used in the lateral guidance algorithm. The same section also describes how to make various mission-related decisions online during flight, such as when to start turning and when a waypoint is achieved. The lateral guidance law is then presented, followed by the design of a robust multivariable H∞ controller for roll control and stability augmentation. The controller uses the ailerons and rudder for control of roll angle and stabilization of yaw rate of the vehicle. The reference roll angle is generated by the nonlinear guidance law. The sensors available on-board the vehicle do not measure yaw rate; hence, a practical method of its estimation is proposed. The entire guidance and control scheme is implemented on the flight control computer of the actual aerial vehicle and taken to flight. Flight test results for different mission profiles are presented and discussed.
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Vinyas, M., G. Srinivasa Rao, C. S. Venkatesha, and M. Vishwas. "Design Improvement and Structural Analysis of a Carbon Fiber Reinforced Polymer Star Sensor "Baffle"." Advanced Engineering Forum 15 (February 2016): 92–105. http://dx.doi.org/10.4028/www.scientific.net/aef.15.92.
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For any space mission to be successful it is necessary to guide the satellite to revolve in the right orbit and gather all the required data without any flaws. Among the many spacecraft subsystems contributing in this regard, Star sensors are the attitude estimation sensors installed in the satellites in order to determine the exact location of the satellite. It helps to bring back the satellite to the required position if there is any deviation from its path. Star sensor captures the image of any of the predetermined reference star. This image is compared with that of the image of the same star captured from the Earth. By this comparison and with the help of star catalogs, digitizers and microprocessors, the attitude and inclination of the satellite is determined.
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Quarta, Alessandro A., and Giovanni Mengali. "E-Sail Optimal Trajectories to Heliostationary Points." Aerospace 10, no. 2 (February 17, 2023): 194. http://dx.doi.org/10.3390/aerospace10020194.
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The aim of this paper is to investigate the performance of a robotic spacecraft, whose primary propulsion system is an electric solar wind sail (E-sail), in a mission to a heliostationary point (HP)—that is, a static equilibrium point in a heliocentric and inertial reference frame. A spacecraft placed at a given HP with zero inertial velocity maintains that heliocentric position provided the on-board thrust is able to counterbalance the Sun’s gravitational force. Due to the finite amount of storable propellant mass, a prolonged mission toward an HP may be considered as a typical application of a propellantless propulsion system. In this respect, previous research has been concentrated on the capability of high-performance (photonic) solar sails to reach and maintain such a static equilibrium condition. However, in the case of a solar-sail-based spacecraft, an HP mission requires a sail design with propulsive characteristics that are well beyond the capability of current or near-future technology. This paper shows that a medium-performance E-sail is able to offer a viable alternative to the use of photonic solar sails. To that end, we discuss a typical HP mission from an optimal viewpoint, by looking for the minimum time trajectory necessary for a spacecraft to reach a given HP. In particular, both two- and three-dimensional scenarios are considered, and the time-optimal mission performance is analyzed parametrically as a function of the HP heliocentric position. The paper also illustrates a potential mission application involving the observation of the Sun’s poles from such a static inertial position.
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Wickens, Chris, Gaia Dempsey, Andrew Pringle, Lucas Kazansky, and Stefanie Hutka. "Developing and Evaluating an Augmented Reality Interface to Assist the Joint Tactical Air Controller by Applying Human Performance Models." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 62, no. 1 (September 2018): 686–90. http://dx.doi.org/10.1177/1541931218621155.
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We developed a 3D augmented reality head mounted display (DARSADS-SVS HMD) interface to support the Joint Tactical Air Controller (JTAC). The JTAC’s job is to integrate information about enemy attack units and nearby friendly forces and direct aircraft equipped with weapons to neutralize the enemy via close air support (CAS), while also safely routing air traffic. The JTAC’s numerous and often overlapping tasks involve maintaining detailed situational awareness (SA) of a large quantity of information, and making rapid decisions that carry life-or-death consequences. Thus, the JTAC role requires many different cognitive operations across different mission phases. Designing an effective human-factored system that supports maximum SA while minimizing cognitive load required us to harness computational cognitive models of SA-supporting visual scanning, display layout, 3D frame-of-reference transformations, clutter, legibility and working memory. We applied such models to different phases of the JTAC mission (e.g., airspace management, call-for-fire), establishing a Figure of Merit (FOM) for each given design by summing FOMs across models, thus creating a mechanism to evaluate designs based upon their balanced impact on competing cognitive drivers. Models were differentially weighted for each phase, according to the relative importance of the relevant cognitive process to the phase in question. In this research paper, we illustrate two such design comparisons.
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Basir, Azhar, Abdul Fadlil, and Imam Riadi. "Enterprise Architecture Planning Sistem Informasi Akademik Dengan TOGAF ADM." J-SAKTI (Jurnal Sains Komputer dan Informatika) 3, no. 1 (March 4, 2019): 1. http://dx.doi.org/10.30645/j-sakti.v3i1.91.
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The role of information technology greatly influences the improvement of a higher education governance, so that universities today should have models and standards that can be implemented as a reference in enhancing harmony between business strategies and information technology. Enterprise Architecture planning (EAP) is one of the methodologies that can be applied in planning information architecture, the stages in EAP consist of data architecture, application architecture, technology architecture and how the design that has been made can be implemented to support business activities, to achieve the organization's mission.
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Johnston, K. J., P. K. Seidelmann, R. D. Reasenberg, R. Babcock, and J. D. Phillips. "Newcomb Astrometric Satellite." Symposium - International Astronomical Union 166 (1995): 331–34. http://dx.doi.org/10.1017/s0074180900228301.
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Newcomb is a design concept for an astrometric optical interferometer satellite with a nominal single measurement accuracy of 100 microarcseconds. In a 30-month mission life, it will make scientifically interesting measurements of O stars, RR Lyrae and Cepheid distances, probe dark matter in our Galaxy via parallax measurements of K giants in the disk, establish a reference grid with internal consistency better than 50 microarcseconds, and lay the groundwork for the larger optical interferometers that are expected to produce a profusion of scientific results during the next century.
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Chiu, Yi-Chung, Loren C. Chang, Chi-Kuang Chao, Tzu-Ya Tai, Kai-Lun Cheng, Hsin-Tzu Liu, Rong Tsai-Lin, et al. "Lessons Learned from IDEASSat: Design, Testing, on Orbit Operations, and Anomaly Analysis of a First University CubeSat Intended for Ionospheric Science." Aerospace 9, no. 2 (February 18, 2022): 110. http://dx.doi.org/10.3390/aerospace9020110.
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Given the pervasive use of satellite and over the horizon wireless communication technology in modern society, ionospheric disturbances that can disrupt such services are a crucial consideration. Ionospheric irregularities, plasma bubbles and other phenomena can have a great impact on satellite navigation and communications, impacting other systems reliant on such technologies. The Ionospheric Dynamics and Attitude Subsystem Satellite (IDEASSat) was a 3U developed by National Central University (NCU) to measure irregularities in the ionosphere, as well as to establish spacecraft engineering and operations capacity at NCU. The onboard Compact Ionospheric Probe (CIP) could measure high-resolution plasma parameters, which can be used for identifying ionospheric irregularities that can cause scintillation in satellite navigation and communications signals. Part of the spacecraft sub-systems were independently designed and developed by students, who were also responsible for integration, testing, and operations. IDEASSat was successfully launched into low Earth orbit on 24 January 2021, and then began mission operations. The spacecraft successfully demonstrated three-axis attitude stabilization and control, tracking, telemetry and command (TT&C), as well as flight software and ground systems that could support autonomous operation. The spacecraft experienced a critical anomaly 22 days after launch, followed by a 1.5-month communications blackout. The spacecraft briefly recovered from the blackout for long enough to replay flight data, which allowed for the cause of the blackout to be determined as an inability of the electrical power subsystem reset circuit to recover from an ionizing radiation induced single event latch-up. Although the mission was not completed, flight data obtained during the mission will help to improve the designs of future spacecraft in development at NCU. This paper will introduce IDEASSat’s final flight model design and implementation, integration, testing, environmental verification, and failure analysis, and will review the performance of the spacecraft during on-orbit operations. The results and experiences encountered in implementation and operations of the IDEASSat mission are presented here as a reference for other university small satellite teams.
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Li, Xiangyu, Yapeng Zhao, Hailin Miao, and Wangyong. "Design and Research of a hanging and releasing unmanned craft deployment and recovery." Journal of Physics: Conference Series 2419, no. 1 (January 1, 2023): 012057. http://dx.doi.org/10.1088/1742-6596/2419/1/012057.
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Abstract The application potential of unmanned craft in navigation, patrol, detection, search and rescue, maritime interception, and other fields is becoming increasingly prominent, the research and development of unmanned craft in various countries have been strengthened, however, the research and development of deployment and recovery technology, which is matched with the combat mission of unmanned craft, as the core technology, is relatively lagging. In this paper, a hanging and releasing device for the unmanned craft is designed, the design scheme of the deployment and recovery device is introduced, the risk of collision between the unmanned boat and the main ship is evaluated, and structural calculations are performed using finite element analysis software. The results show that the deployment and recovery device scheme of the unmanned craft is reasonable and feasible, which provides guidance and reference for the design of relevant devices in the future.
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Wang, He, Jiadong Shi, Jianzhong Wang, Hongfeng Wang, Yiming Feng, and Yu You. "Design and Modeling of a Novel Transformable Land/Air Robot." International Journal of Aerospace Engineering 2019 (February 4, 2019): 1–10. http://dx.doi.org/10.1155/2019/2064131.
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This paper describes a novel transformable land/air robot that is capable of terrestrial locomotion and aerial locomotion. What is unusual about the robot is that it can transform between the two modes of locomotion at will through the transformable mechanism, allowing the robot to overcome large obstacles in their mission environment. The wheel mechanism of the robot is shared by both terrestrial and aerial locomotion, instead of simply adding a quadrotor to a wheeled mobile robot. The objective of this paper is to design the robot and establish the kinematic and dynamic models for the transformable process. Herein, we focus on the design of the driving wheels and transformable mechanism. A series of experiments about the energy analysis and the transformation from aerial locomotion mode to terrestrial locomotion mode were performed with the physical prototype; the experiment results confirmed the validity of our design and the theoretical analysis that are helpful to optimize the key parameters in our design. Moreover, our work can provide a reference for the study of the flying car.
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Boubrima, Ahmed, and Edward W. Knightly. "Robust Environmental Sensing Using UAVs." ACM Transactions on Internet of Things 2, no. 4 (November 30, 2021): 1–20. http://dx.doi.org/10.1145/3464943.
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In this article, we first investigate the quality of aerial air pollution measurements and characterize the main error sources of drone-mounted gas sensors. To that end, we build ASTRO+, an aerial-ground pollution monitoring platform, and use it to collect a comprehensive dataset of both aerial and reference air pollution measurements. We show that the dynamic airflow caused by drones affects temperature and humidity levels of the ambient air, which then affect the measurement quality of gas sensors. Then, in the second part of this article, we leverage the effects of weather conditions on pollution measurements’ quality in order to design an unmanned aerial vehicle mission planning algorithm that adapts the trajectory of the drones while taking into account the quality of aerial measurements. We evaluate our mission planning approach based on a Volatile Organic Compound pollution dataset and show a high-performance improvement that is maintained even when pollution dynamics are high.
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Widayat, Setiyo, and M. Suksrisno Mardiyanto. "Cloud IaaS Enterprise Architecture Design on Multiplatform Integrated Information System using Cloud Ecosystem Reference Model and TOGAF." SPECTA Journal of Technology 2, no. 1 (November 27, 2019): 19–26. http://dx.doi.org/10.35718/specta.v2i1.91.
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Currently Information Technology is increasingly needed by many organizations. Implementation of inappropriate IT in the organization will be a burden, even can hinder the development if not in accordance with the vision and mission of the organization. Weill and Ross also stated, 48 percent of companies that do IT investment cannot increase the expected value. A solid foundation in the execution process of IT implementation plays an important role in determining the success or failure of the company to achieve the desired goals. To build a solid foundation on the execution process of IT implementation, one of the important things to note is Enterprise Architecture (AE). Enterprise architecture provides a long-term view of the processes, systems and technologies in the company, so there is a harmony between business and IT both for now and for the future to achieve the desired goals. Currently the use of cloud computing technology increasingly used in organizations. Organizations typically have a variety of different platform integrated applications that are used to support their business processes. There are many frameworks used to build AE, but there is no AE framework specifically addressing AE design on cloud computing and supports multiplatform and cloud-based IaaS. This paper discusses the use of TOGAF and CERM to educational institution that have many integrated multiplatform applications. AE design that was built is validated by using Enterprise Realization Score Card (EARS) to assess whether it can be implemented well in the organization.
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Liang, Xiaohua, Wei Zhao, Min Dong, and Hanping Qiu. "Multi-axis vibration test technology of satellite based on vector-fixture’s design and applications." Vibroengineering PROCEDIA 46 (November 18, 2022): 27–32. http://dx.doi.org/10.21595/vp.2022.22959.
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Aiming at the problems that the three-direction uniaxial sequential vibration test cannot effectively simulate the real launch environment of the satellite, and the high cost of the multi-axis shaker and the limitation of engineering application, the multi-axis vibration test scheme based on vector-fixture is proposed. Taking the vibration magnitude of uniaxial vibration test on the satellite mounting surface as equivalent reference, the appropriate vector direction is determined to carry out vector-fixture design. By analyzing the multi-axial vibration test data of the real structure of a satellite, it can be seen that: The “satellite-fixture” mounting surface can reach the set vibration magnitude at low frequencies, and undertest occurs at high frequency due to structural resonance and other factors; By optimizing the control strategy, the degree of over-test and under-test in the three directions can be balanced. According to the mission characteristics and development cycle of micro-nano satellites, this paper provides an efficient vibration test scheme.
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Marco, Agostino De, Vittorio Trifari, Fabrizio Nicolosi, and Manuela Ruocco. "A Simulation-Based Performance Analysis Tool for Aircraft Design Workflows." Aerospace 7, no. 11 (October 30, 2020): 155. http://dx.doi.org/10.3390/aerospace7110155.
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A simulation-based approach for take-off and landing performance assessments is presented in this work. In the context of aircraft design loops, it provides a detailed and flexible formulation that can be integrated into a wider simulation methodology for a complete commercial aviation mission. As a matter of fact, conceptual and preliminary aircraft design activities require iterative calculations to quickly make performance predictions on a set of possible airplane configurations. The goal is to search for a design that best fits all top level aircraft requirements among the results of a great number of multi-disciplinary analyses, as fast as possible, and with a certain grade of accuracy. Usually, such a task is carried out using statistical or semi-empirical approaches which can give pretty accurate results in no time. However, those prediction methods may be inappropriate when dealing with innovative aircraft configurations or whenever a higher level of accuracy is necessary. Simulation-based design has become crucial to make the overall process affordable and effective in cases where higher fidelity analyses are required. A common example when flight simulations can be effectively used to support a design loop is given by aircraft mission analyses and performance predictions. These usually include take-off, climb, en route, loiter, approach, and landing simulations. This article introduces the mathematical models of aircraft take-off and landing and gives the details of how they are implemented in the software library JPAD. These features are not present in most of the currently available pieces of preliminary aircraft design software and allow one to perform high fidelity, simulation-based take-off and landing analyses within design iterations. Although much more detailed than classical semi-empirical approaches, the presented methodologies require very limited computational effort. An application of the proposed formulations is introduced in the second part of the article. The example considers the Airbus A220-300 as a reference aircraft model and includes complete take-off and landing performance studies, as well as the simulation of both take-off and landing certification noise trajectories.
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Bouwer, G., C.-H. Oertel, and W. von Grünhagen. "Autonomous helicopter hover positioning by optical tracking." Aeronautical Journal 99, no. 984 (April 1995): 145–49. http://dx.doi.org/10.1017/s0001924000027123.
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SummaryThe design of control systems for helicopters in hover and at low speed is a basic requirement for the extension of mission profiles and new mission demands. A special task for various applications is the position hold under wind and gust conditions above a ground fixed or moving target, like a shipboard reference, or a small vessel or lifeboat in rescue missions. For the solution of this problem a controller concept was developed and the feasibility was proven and successfully demonstrated in flight tests.The in-flight helicopter simulator ATTHeS of the DLR has been equipped by the Institute of Flight Mechanics with an innovative measurement system for the hover position above a target. A video camera in combination with a highly parallel computer system for processing the optical information was used as an integra ted sensor system for the measurement of the relative position of the aircraft to a target. Based on the existing well-proven flight control laws of ATTHeS for the forward flight condition, which are implemented for handling qualities investigations, these control laws were modified and adapted to fulfil the special requirements of the position hold task, including altitude hold and heading hold capabilities. The integrated system of optical position sensor and control computer enables the helicopter to hover automatically above a defined target in constant altitude and with constant heading. Flight tests above a moving car under wind and gust conditions underline the future potential of the overall system to be used under operational conditions.
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Weiss, Kevin, Michel Rottleuthner, Thomas C. Schmidt, and Matthias Wählisch. "PHiLIP on the HiL: Automated Multi-Platform OS Testing With External Reference Devices." ACM Transactions on Embedded Computing Systems 20, no. 5s (October 31, 2021): 1–26. http://dx.doi.org/10.1145/3477040.
Full textAbstract:
Developing an operating systems (OSs) for low-end embedded devices requires continuous adaptation to new hardware architectures and components, while serviceability of features needs to be assured for each individual platform under tight resource constraints. It is challenging to design a versatile and accurate heterogeneous test environment that is agile enough to cover a continuous evolution of the code base and platforms. This mission is even more challenging when organized in an agile open-source community process with many contributors such as for the RIOT OS. Hardware in the Loop (HiL) testing and Continuous Integration (CI) are automatable approaches to verify functionality, prevent regressions, and improve the overall quality at development speed in large community projects. In this paper, we present PHiLIP (Primitive Hardware in the Loop Integration Product), an open-source external reference device together with tools that validate the system software while it controls hardware and interprets physical signals. Instead of focusing on a specific test setting, PHiLIP takes the approach of a tool-assisted agile HiL test process, designed for continuous evolution and deployment cycles. We explain its design, describe how it supports HiL tests, evaluate performance metrics, and report on practical experiences of employing PHiLIP in an automated CI test infrastructure. Our initial deployment comprises 22 unique platforms, each of which executes 98 peripheral tests every night. PHiLIP allows for easy extension of low-cost, adaptive testing infrastructures but serves testing techniques and tools to a much wider range of applications.
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D’Amato, Egidio, Immacolata Notaro, Giulia Panico, Luciano Blasi, Massimiliano Mattei, and Alessia Nocerino. "Trajectory Planning and Tracking for a Re-Entry Capsule with a Deployable Aero-Brake." Aerospace 9, no. 12 (December 18, 2022): 841. http://dx.doi.org/10.3390/aerospace9120841.
Full textAbstract:
In the last decade, the increasing use of NanoSats and CubeSats has made the re-entry capsule an emerging research field needing updates in configuration and technology. In particular, the door to advancements in terms of efficiency and re-usability has been opened by the introduction of inflatable and/or deployable aerodynamic brakes and the use of on-board electronics for active control. Such technologies allow smaller sizes at launch, controlled re-entries, and safe recovery. This paper deals with the design of a guidance and control algorithm for the re-entry of a capsule with a deployable aero-brake. A trajectory optimization model is used both in the mission planning phase to design the reference re-entry path and during the mission to update the trajectory in case of major deviations from the prescribed orbit, thanks to simplifications aimed at reducing the computational burden. Successively, a trajectory tracking controller, based on Nonlinear Model Predictive Control (NMPC), is able to modulate the opening of the aero-brake in order to follow the planned trajectory towards the target. A robustness analysis was carried out, via numerical simulations, to verify the reliability of the proposed controller in the presence of model uncertainties, orbital perturbations, and measurement noise.