Artículos de revistas: "Autonomous satellites"

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Gao, Youtao, Tanran Zhao, Bingyu Jin, Junkang Chen y Bo Xu. "Autonomous Orbit Determination for Lagrangian Navigation Satellite Based on Neural Network Based State Observer". International Journal of Aerospace Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/9734164.

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In order to improve the accuracy of the dynamical model used in the orbit determination of the Lagrangian navigation satellites, the nonlinear perturbations acting on Lagrangian navigation satellites are estimated by a neural network. A neural network based state observer is applied to autonomously determine the orbits of Lagrangian navigation satellites using only satellite-to-satellite range. This autonomous orbit determination method does not require linearizing the dynamical mode. There is no need to calculate the transition matrix. It is proved that three satellite-to-satellite ranges are needed using this method; therefore, the navigation constellation should include four Lagrangian navigation satellites at least. Four satellites orbiting on the collinear libration orbits are chosen to construct a constellation which is used to demonstrate the utility of this method. Simulation results illustrate that the stable error of autonomous orbit determination is about 10 m. The perturbation can be estimated by the neural network.

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2

Wang, Haihong, Zhonggui Chen, Jinjun Zheng y Haibin Chu. "A New Algorithm for Onboard Autonomous Orbit Determination of Navigation Satellites". Journal of Navigation 64, S1 (14 de octubre de 2011): S162—S179. http://dx.doi.org/10.1017/s0373463311000397.

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Autonomous orbit determination of a navigation constellation is the process by which the orbit parameters of navigation satellites are autonomously calibrated onboard the satellites without the need for external aids. It commonly uses a satellite onboard data processing unit and a filtering method to process the measurements of inter-satellite ranges. The onboard data processing unit is the main module of autonomous navigation systems. In this paper, the two main factors that affect the accuracy of autonomous orbit determination for a navigation constellation are discussed first, and then a distributed onboard algorithm for autonomous orbit determination of navigation satellites is proposed. This method is based on a long-term ephemeris prediction and is suitable for the satellite hardware capability. The main feature of this method is that both the distributed computing method and an onboard analytical state transition matrix are used to process inter-satellite range measurements. One of the main advantages of this approach is high-speed computing since the amount of calculations needed is significantly less than that of the centralised computing method and those distributed methods that need to use an onboard numerical integrator. Another advantage of this approach is that the use of the onboard analytical state transition matrix algorithm can save a great amount of resources for both ground-to-satellite data transmissions and data storage units in satellites’ hardware. This could result in substantial cost reduction for space missions. Finally, a simulation method used for testing the proposed algorithm is presented. Results of tests over a period of 90 days show that the user range error of autonomous orbit determination derived from the proposed method is less than three metres.

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3

Li, Muzi, Bo Xu y Jun Sun. "Autonomous Orbit Determination for a Hybrid Constellation". International Journal of Aerospace Engineering 2018 (26 de septiembre de 2018): 1–13. http://dx.doi.org/10.1155/2018/4843061.

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A new orbit determination scheme targeting communication and remote sensing satellites in a hybrid constellation is investigated in this paper. We first design one such hybrid constellation with a two-layer configuration (LEO/MEO) by optimizing coverage and revisit cycle. The main idea of the scheme is to use a combination of imagery, altimeter data, and inter-satellite range data as measurements and determine orbits of the satellites in the hybrid constellation with the help of the extended Kalman filter (EKF). The performance of the new scheme is analyzed with Monte Carlo simulations. We first focus on an individual remote sensing satellite and compared the performance of orbit determination using only imagery with its counterpart using both imagery and altimeter measurements. Results show that the performance improves when imagery is used with altimeter data pointing to geometer calibration sites but declines when used with ocean altimeter data. We then expand the investigation to the whole constellation. When inter-satellite range data is added, orbits of all the satellites in the hybrid constellation can be autonomously determined. We find that the combination of inter-satellite range data with remote sensing observations lead to a further improvement in orbit determination precision for LEO satellites. Our results also show that the performance of the scheme would be affected when remote sensing observations on certain satellites are absent.

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4

Kitamura, Mitsunori, Yoichi Yasuoka, Taro Suzuki, Yoshiharu Amano y Takumi Hashizume. "Path Planning for Autonomous Vehicles Using QZSS and Satellite Visibility Map". Journal of Robotics and Mechatronics 25, n.º 2 (20 de abril de 2013): 400–407. http://dx.doi.org/10.20965/jrm.2013.p0400.

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This paper describes a path planning method that uses the Quasi-Zenith Satellites System(QZSS) and a satellite visibility map for autonomous vehicles. QZSS is a positioning system operated by Japan that has an effect similar to an increase in the number of GPS satellites. Therefore, QZSS can be used to improve the availability of GPS positioning. A satellite visibility map is a special map that simulates the number of visible satellites at all points on the map. The vehicle can use the satellite visibility map to determine the points that receive more satellite signals. The proposed method generates the artificial potential fields from the satellite visibility map and obstacle information around the vehicle, and it generates the path following the potential fields. Thereby, the vehicle can select the path that has more satellite signals, improving the availability of GPS fixed solutions. Hence, the vehicle can reduce the accumulated error by dead reckoning, and it can improve the safety of self-control. In this study, we evaluate the satellite visibility maps and the path planning method. The results show that the proposed method does improve the availability of GPS fixed solutions.

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Mcinroy, J., L. Robertson y R. Erwin. "Autonomous distant visual silhouetting of satellites". IEEE Transactions on Aerospace and Electronic Systems 44, n.º 2 (abril de 2008): 801–8. http://dx.doi.org/10.1109/taes.2008.4560222.

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Alfonso, Màrius Josep Fullana i., Diego Pascual Sáez Milán, Josep Vicent Arnau i. Córdoba y Neus Puchades Colmenero. "Some Improvements on Relativistic Positioning Systems". Applied Mathematics and Nonlinear Sciences 3, n.º 1 (13 de mayo de 2018): 161–66. http://dx.doi.org/10.21042/amns.2018.1.00012.

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AbstractWe make some considerations about Relativistic Positioning Systems (RPS). Four satellites are needed to position a user. First of all we define the main concepts. Errors should be taken into account. Errors depend on the Jacobian transformation matrix. Its Jacobian is proportional to the tetrahedron volume whose vertexes are the four tips of the receiver-satellite unit vectors. If the four satellites are seen by the user on a circumference in the sky, then, the Jacobian and the tetrahedron volume vanish. The users we consider are spacecraft. Spacecraft to be positioned cannot be close to a null Jacobian satellites-user configuration. These regions have to be avoided choosing an appropriate set of four satellites which are not seen too close to the same circumference in the sky. Errors also increase as the user spacecraft separates from the emission satellite region, since the tetrahedron volume decreases.We propose a method to autonomously potion a user-spacecraft which can test our method. This positioning should be compared with those obtained by current methods. Finally, a proposal to position a user-spacecraft moving far from Earth, with suitable devices (autonomous), is presented.

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7

Suzuki, Taro, Mitsunori Kitamura, Yoshiharu Amano y Nobuaki Kubo. "Autonomous Navigation of a Mobile Robot Based on GNSS/DR Integration in Outdoor Environments". Journal of Robotics and Mechatronics 26, n.º 2 (20 de abril de 2014): 214–24. http://dx.doi.org/10.20965/jrm.2014.p0214.

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This paper describes the development of a mobile robot system and an outdoor navigationmethod based on global navigation satellite system (GNSS) in an autonomous mobile robot navigation challenge, called the Tsukuba Challenge, held in Tsukuba, Japan, in 2011 and 2012. The Tsukuba Challenge promotes practical technologies for autonomous mobile robots working in ordinary pedestrian environments. Many teams taking part in the Tsukuba Challenge used laser scanners to determine robot positions. GNSS was not used in localization because its positioning has multipath errors and problems in availability. We propose a technique for realizing multipath mitigation that uses an omnidirectional IR camera to exclude “invisible” satellites, i.e., those entirely obstructed by a building and whose direct waves therefore are not received. We applied GPS / dead reckoning (DR) integrated based on observation data from visible satellites determined by the IR camera. Positioning was evaluated during Tsukuba Challenge 2011 and 2012. Our robot ran the 1.4 km course autonomously and evaluation results confirmed the effectiveness of our proposed technique and the feasibility of its highly accurate positioning.

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8

Liao, Shilong, Zhaoxiang Qi y Zhenghong Tang. "A Differential Measurement Method for Solving the Ephemeris Observability Issues in Autonomous Navigation". Journal of Navigation 68, n.º 6 (25 de mayo de 2015): 1133–40. http://dx.doi.org/10.1017/s0373463315000417.

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The autonomous navigation of navigation and positioning systems such as the Global Positioning System (GPS) and other Global Navigation Satellite Systems (GNSS) was motivated to improve accuracy and survivability of the navigation function for 180 days without ground contact. These improvements are accomplished by establishing inter-satellite links in the constellation for pseudo-range observations and communications between satellites. But observability issues arise for both ephemeris and clock since the pseudo-range describes only the relative distance between satellites. A differential measurement method is proposed to measure the rotation of the constellation as a whole for the first time. The feasibility of the proposed method is verified by simulations.

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9

Liu, Li, Wei Zheng y Guojian Tang. "Autonomous Positioning of Satellite Constellations via X-ray Pulsar Measurements". Journal of Navigation 66, n.º 5 (21 de junio de 2013): 671–82. http://dx.doi.org/10.1017/s0373463313000325.

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A novel autonomous positioning approach based on X-ray pulsars is proposed in this paper. First, the principles of the pulsar–based measurement model and the inter-satellite range model in the autonomous positioning of satellite constellations are presented. The observability of the pulsar-based measurement model is then shown. Second, the autonomous positioning algorithms, including measurement models and orbital dynamics models, are formulated using an unscented Kalman filter to estimate the position vectors of satellites. Finally, the feasibility of the proposed measurement scheme compared with an inter-satellite range scheme is illustrated by numerical simulation. The results show that the proposed approach can keep the satellite state convergent, and achieve position accuracies of 2 m. The proposed scheme provides a promising approach for autonomous absolute positioning of constellation systems by using X-ray pulsars.

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10

Ning, Xiaolin, Xin Ma, Cong Peng, Wei Quan y Jiancheng Fang. "Analysis of Filtering Methods for Satellite Autonomous Orbit Determination Using Celestial and Geomagnetic Measurement". Mathematical Problems in Engineering 2012 (2012): 1–16. http://dx.doi.org/10.1155/2012/267875.

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Satellite autonomous orbit determination (OD) is a complex process using filtering method to integrate observation and orbit dynamic equations effectively and estimate the position and velocity of a satellite. Therefore, the filtering method plays an important role in autonomous orbit determination accuracy and time consumption. Extended Kalman filter (EKF), unscented Kalman filter (UKF), and unscented particle filter (UPF) are three widely used filtering methods in satellite autonomous OD, owing to the nonlinearity of satellite orbit dynamic model. The performance of the system based on these three methods is analyzed under different conditions. Simulations show that, under the same condition, the UPF provides the highest OD accuracy but requires the highest computation burden. Conclusions drawn by this study are useful in the design and analysis of autonomous orbit determination system of satellites.

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11

Huang, Feijiang, Xiaochun Lu, Guangcan Liu, Liping Sun, Wang Sheng y Yingde Wang. "Improvement and Simulation of an Autonomous Time Synchronization Algorithm for a Layered Satellite Constellation". Mathematical Problems in Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/136301.

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Autonomous time synchronization for satellite constellations is a key technology to establish a constellation system time without the use of a ground station. The characteristics of satellite visibility time for layered satellite constellations containing geostationary earth orbit (GEO), inclined geosynchronous orbit (IGSO), and medium earth orbit (MEO) satellites are simulated by establishing a visible satellite model. Based on the satellite visible simulation results for a layered constellation, this study investigates the autonomous time synchronization algorithm that corresponds to the layered constellation structure, analyzes the main error of the time synchronization algorithm, and proposes methods to improve the characteristics of satellite movement in the constellation. This study uses an improved two-way time synchronization algorithm for autonomous time synchronization in the GEO-MEO satellite layer of a layered satellite constellation. The simulation results show that in a condition with simulation errors, the time synchronization precision of this improved algorithm can be controlled within 5 ns and used in high-precision autonomous time synchronization between layered satellite constellations.

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12

He, Yongming, Lei He, Yuan Wang, Yu Xiao, Yingwu Chen y Lining Xing. "Autonomous Mission Replanning Method for Imaging Satellites Considering Real-Time Weather Conditions". Journal of Computational and Theoretical Nanoscience 13, n.º 10 (1 de octubre de 2016): 6967–73. http://dx.doi.org/10.1166/jctn.2016.5654.

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During the observations made by imaging satellites, meteorological factors are likely to change frequently. The vagaries of weather conditions and significant effects on the actual observation results mean that there is an urgent need to apply more intelligence to satellite mission planning. Thus, this paper describes an autonomous replanning method for imaging satellites that considers the real-time weather conditions. Considering the characteristics of different input data, this method replans the low-yield task set and fine-tunes others to improve profitability. Moreover, the proposed method can heuristically select the appropriate adjustment rule to achieve autonomous satellite mission planning. A series of simulations with various task quantities and in different environments shows that the proposed method can respond effectively to real-time weather changes, and can steadily improve the total profits in a variety of weather conditions during Earth observation activities.

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13

Zhao, Jing, Chengdong Xu, Yimei Jian y Pengfei Zhang. "A Modified Range Consensus Algorithm Based on GA for Receiver Autonomous Integrity Monitoring". Mathematical Problems in Engineering 2020 (22 de junio de 2020): 1–13. http://dx.doi.org/10.1155/2020/8969032.

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With the considerable increase of visible satellites for positioning, the fault detection and identification performance of Range Consensus (RANCO) algorithm for Receiver Autonomous Integrity Monitoring (RAIM) will significantly be improved. However, the calculation amount of RANCO algorithm will exponentially increase for the sharp addition of visible satellite subsets. This paper proposes a modified RANCO algorithm based on genetic algorithm (GA-RANCO) for RAIM to inhibit the exponentially expanded calculation amount. To reduce the calculation amount in searching the optimal minimal necessary subset (MNS), the preselection step is developed to speed up the convergence process of GA-RANCO. It is executed to exclude the chromosome-represented MNS for which the count of faulty satellites will exceed the upper limit of independent simultaneous satellite faults to be monitored. Mathematical simulations are introduced to determine the GA parameters, and simulation experiments under different schemes are designed to evaluate the performance of GA-RANCO algorithm. Results illustrate that the time consumption under a large number of visible satellites of GA-RANCO is much lower than that of RANCO and the faulty detection and identification performance of GA-RANCO is the same as that of RANCO.

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14

Hicks, Kerry D. y William E. Wiesel. "Autonomous orbit determination system for earth satellites". Journal of Guidance, Control, and Dynamics 15, n.º 3 (mayo de 1992): 562–66. http://dx.doi.org/10.2514/3.20876.

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15

Guelman, Mauricio M. "Geostationary satellites autonomous closed loop station keeping". Acta Astronautica 97 (abril de 2014): 9–15. http://dx.doi.org/10.1016/j.actaastro.2013.12.009.

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16

Radišić, Tomislav, Doris Novak y Tino Bucak. "The Effect of Terrain Mask on RAIM Availability". Journal of Navigation 63, n.º 1 (1 de diciembre de 2009): 105–17. http://dx.doi.org/10.1017/s0373463309990294.

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Receiver Autonomous Integrity Monitoring (RAIM) is a method, used by an aircraft's receiver, for detecting and isolating faulty satellites of the Global Navigation Satellite System (GNSS). In order for a receiver to be able to detect and isolate a faulty satellite using a RAIM algorithm, a couple of conditions must be met: a minimum number of satellites, and an adequate satellite geometry. Due to the highly predictable orbits of the GPS satellites, a RAIM availability prediction can be done easily. A number of RAIM methods exist; however, none of them takes into account the precise terrain masking of the satellites for the specific location. They consider a uniform fixed mask angle over the whole horizon. This paper will introduce the variable mask RAIM algorithm in order to show to what extent the terrain can affect the RAIM availability and how much it differs from the conventional algorithms.

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17

Wang, Huibin, Yongmei Cheng, Cheng Cheng, Song Li y Zhenwei Li. "Research on Satellite Selection Strategy for Receiver Autonomous Integrity Monitoring Applications". Remote Sensing 13, n.º 9 (29 de abril de 2021): 1725. http://dx.doi.org/10.3390/rs13091725.

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Satellite selection is an effective way to overcome the challenges for the processing capability and channel limitation of the receivers due to superabundant satellites in view. The satellite selection strategies have been widely investigated to construct the subset with high accuracy but deserve further studies when applied to safety-critical applications such as the receiver autonomous integrity monitoring (RAIM) technique. In this study, the impacts of subset size on the accuracy and integrity of the subset and computation load are analyzed at first to confirm the importance of the satellite selection strategy for the RAIM process. Then the integrated performance impact of a single satellite on the current subset is evaluated according to the performance requirement of the flight phase. Subsequently, a performance-requirement-driven fast satellite selection algorithm is proposed based on the impact evaluation to construct a relatively small subset that satisfies the accuracy and integrity requirements. Comparison simulations show that the proposed algorithm can keep similar accuracy and better integrity performances than the geometric algorithm and the downdate algorithm when the subset size is fixed to 12, and can achieve an average 1.0 to 2.0 satellites smaller subset in the Lateral Navigation (LNAV) and approach procedures with vertical guidance (APV-I) horizontal requirement trial. Thus, it is suitable for real-time RAIM applications and low-cost navigation devices.

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Nowak, Aleksander. "Dynamic GNSS Mission Planning Using DTM for Precise Navigation of Autonomous Vehicles". Journal of Navigation 70, n.º 3 (17 de octubre de 2016): 483–504. http://dx.doi.org/10.1017/s0373463316000679.

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Nowadays, the most widely used method for estimating location of autonomous vehicles in real time is the use of Global Navigation Satellite Systems (GNSS). However, positioning in urban environments using GNSS is hampered by poor satellite geometry due to signal obstruction created by both man-made and natural features of the urban environment. The presence of obstacles is the reason for the decreased number of observed satellites as well as uncertainty of GNSS positioning. It is possible that in some sections of the vehicle route there might not be enough satellites necessary to fix position. It is common to use software for static GNSS measurement campaign planning, but it is often only able to predict satellite visibility at one point. This article presents a proposal for dynamic GNSS mission planning using a Digital Terrain Model (DTM) and dead reckoning. The methodology and sample results of numerical experiments are also described. They clearly show that proper dynamic GNSS mission planning is necessary in order to complete a task by an autonomous vehicle in an obstructed environment.

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Hua, Bing, Zhiwen Zhang, Yunhua Wu y Zhiming Chen. "Autonomous navigation algorithm based on AUKF filter about fusion of geomagnetic and sunlight directions". International Journal of Intelligent Computing and Cybernetics 11, n.º 4 (12 de noviembre de 2018): 471–85. http://dx.doi.org/10.1108/ijicc-07-2017-0087.

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Purpose The geomagnetic field vector is a function of the satellite’s position. The position and speed of the satellite can be determined by comparing the geomagnetic field vector measured by on board three-axis magnetometer with the standard value of the international geomagnetic field. The geomagnetic model has the disadvantages of uncertainty, low precision and long-term variability. Therefore, accuracy of autonomous navigation using the magnetometer is low. The purpose of this paper is to use the geomagnetic and sunlight information fusion algorithm to improve the orbit accuracy. Design/methodology/approach In this paper, an autonomous navigation method for low earth orbit satellite is studied by fusing geomagnetic and solar energy information. The algorithm selects the cosine value of the angle between the solar light vector and the geomagnetic vector, and the geomagnetic field intensity as observation. The Adaptive Unscented Kalman Filter (AUKF) filter is used to estimate the speed and position of the satellite, and the simulation research is carried out. This paper also made the same study using the UKF filter for comparison with the AUKF filter. Findings The algorithm of adding the sun direction vector information improves the positioning accuracy compared with the simple geomagnetic navigation, and the convergence and stability of the filter are better. The navigation error does not accumulate with time and has engineering application value. It also can be seen that AUKF filtering accuracy is better than UKF filtering accuracy. Research limitations/implications Geomagnetic navigation is greatly affected by the accuracy of magnetometer. This paper does not consider the spacecraft’s environmental interference with magnetic sensors. Practical implications Magnetometers and solar sensors are common sensors for micro-satellites. Near-Earth satellite orbit has abundant geomagnetic field resources. Therefore, the algorithm will have higher engineering significance in the practical application of low orbit micro-satellites orbit determination. Originality/value This paper introduces a satellite autonomous navigation algorithm. The AUKF geomagnetic filter algorithm using sunlight information can obviously improve the navigation accuracy and meet the basic requirements of low orbit small satellite orbit determination.

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YongZhi, Wen, Zhang ZeJian y Wu Jie. "High-Precision Navigation Approach of High-Orbit Spacecraft Based on Retransmission Communication Satellites". Journal of Navigation 65, n.º 2 (12 de marzo de 2012): 351–62. http://dx.doi.org/10.1017/s0373463311000671.

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Many countries have presented new requirements for in-orbit space services. Space autonomous rendezvous and docking technology could speed up the development of in-orbit spacecraft and reduce the threat of increasing amounts of space debris. The purpose of this paper is to provide real-time high-precision navigation data for high-orbit spacecraft, thus reducing the cost of ground monitoring for high-orbit spacecraft autonomous rendezvous operations, and to provide technical support for high-orbit spacecraft in-orbit services. This paper proposes a new high-orbit spacecraft autonomous navigation approach, based on a communication satellite transmitting ground navigation signals. It proposes an overall navigation system design, sets up the system information integration model and analyses the precision of the navigation system by simulation research. Through simulation of this navigation method, the positional precision of a spacecraft at an altitude of 40 000 km, can be within 2·6 m with a velocity precision of 0·0011 m/s. The transponding satellite navigation method greatly reduces the development costs by using communication satellites in high-orbit spacecraft navigation instead of launching special navigation satellites. Moreover, the signals of transponding satellite navigation are generated on the ground, which is very convenient and cost-effective for system maintenance. In addition, placing atomic clocks on the ground may also help improve the clock accuracy achieved. In this study, the satellite-based navigation method is for the first time applied in high-orbit spacecraft navigation. The study's data could improve the present lack of effective high-orbit spacecraft navigation methods and provide strong technical support for autonomous rendezvous and docking of high orbital spacecraft, as well as other application fields.

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Li, Jiang, Ma, Lv, Yuan y Li. "LEO Precise Orbit Determination with Inter-Satellite Links". Remote Sensing 11, n.º 18 (11 de septiembre de 2019): 2117. http://dx.doi.org/10.3390/rs11182117.

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Traditional precise orbit determination (POD) for low Earth orbit (LEO) satellites relies on observations from ground stations and onboard receivers. Although the accuracy can reach centimeter level, there are still problems such as insufficient autonomous operation capability. The inter-satellite link (ISL) is a link used for communication between satellites and has a function of dual-way ranging. Numerous studies have shown that observational data using ISLs can be adopted for POD of navigation satellites. In this contribution, we mainly focus on LEO satellites POD with ISLs. First, we design LEO constellations with different numbers of satellites and ISL measurements, based on which the constellations are simulated. Then rough tests of POD using different link topologies are carried out. The results show that in the 60-LEO constellation the average 3-dimensional (3D) orbital errors are 0.112 m using “4-connected” link topology with constant 4 links per satellite and 0.069 m using “all-connected” link topology with theoretically maximum numbers of links. After that, we carry out refined POD experiments with several sets of satellite numbers and different observation accuracy. The results show the higher link ranging accuracy and the more numbers of links bring higher POD precision. POD with ISLs gets bad performance in the case of center of gravity reference when link ranging accuracy is poor and numbers of links are small. When the link accuracy is 40 cm, average 3D orbital errors of 60-LEO constellation are 0.358 m, which can only meet the demand of autonomous navigation. With the constraint of the right ascension of the ascending node (RAAN), POD using ISLs reaches an extremely high precision when adopting a spatial reference provided by navigation satellites. For 120-LEO constellation, the average 3D orbital errors are 0.010 m; for 192-LEO constellation, the errors are 0.006 m.

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Kumar, Vinod y Hari B. Hablani. "Autonomous Formation Keeping of Geostationary Satellites with Regional Navigation Satellites and Dynamics". Journal of Guidance, Control, and Dynamics 40, n.º 3 (marzo de 2017): 563–83. http://dx.doi.org/10.2514/1.g001652.

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Gao, Youtao, Junkang Chen, Bo Xu y Jianhua Zhou. "Research on the Effectiveness of Different Estimation Algorithm on the Autonomous Orbit Determination of Lagrangian Navigation Constellation". International Journal of Aerospace Engineering 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8392148.

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The accuracy of autonomous orbit determination of Lagrangian navigation constellation will affect the navigation accuracy for the deep space probes. Because of the special dynamical characteristics of Lagrangian navigation satellite, the error caused by different estimation algorithm will cause totally different autonomous orbit determination accuracy. We apply the extended Kalman filter and the fading–memory filter to determinate the orbits of Lagrangian navigation satellites. The autonomous orbit determination errors are compared. The accuracy of autonomous orbit determination using fading-memory filter can improve 50% compared to the autonomous orbit determination accuracy using extended Kalman filter. We proposed an integrated Kalman fading filter to smooth the process of autonomous orbit determination and improve the accuracy of autonomous orbit determination. The square root extended Kalman filter is introduced to deal with the case of inaccurate initial error variance matrix. The simulations proved that the estimation method can affect the accuracy of autonomous orbit determination greatly.

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Olive, Xavier. "FDI(R) for satellites: How to deal with high availability and robustness in the space domain?" International Journal of Applied Mathematics and Computer Science 22, n.º 1 (1 de marzo de 2012): 99–107. http://dx.doi.org/10.2478/v10006-012-0007-8.

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FDI(R) for satellites: How to deal with high availability and robustness in the space domain?The European leader for satellite systems and at the forefront of orbital infrastructures, Thales Alenia Space, is a joint venture between Thales (67%) and Finmeccanica (33%) and forms with Telespazio a Space Alliance. Thales Alenia Space is a worldwide reference in telecoms, radar and optical Earth observation, defence and security, navigation and science. It has 11 industrial sites in 4 European countries (France, Italy, Spain and Belgium) with over 7200 employees worldwide. Satellite evolution and the wish to design more autonomous missions imply the enhancement of the satellite architecture and special attention paid to fault management (i.e., Fault Detection, Isolation and Recovery, or FDIR, in space). Nevertheless, the constraints on FDIR techniques and strategies remain the same as for standard missions: robustness, reactive detection, quick isolation/identification and validation. This paper gives an introduction to Fault Tolerance (FT) in the space domain and some principles for the coming FT architectures. The current context of FDIR is presented by describing the approach implemented on telecommunication satellites and, more precisely, on one of the most FDIR sensible subsystems: the AOCS (Attitude and Orbit Control System). Following the current state of FDIR in the space domain, some perspectives are given such as a centralized distributed FDIR strategy for the next generation of autonomous satellites as well as some research tracks and hybrid diagnosis.

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Xu, Zhanpeng, Xiaoqian Chen, Yiyong Huang, Yuzhu Bai y Qifeng Chen. "Collision prediction and avoidance for satellite ultra-close relative motion with zonotope-based reachable sets". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, n.º 11 (14 de noviembre de 2018): 3920–37. http://dx.doi.org/10.1177/0954410018810255.

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Collision prediction and avoidance are critical for satellite proximity operations, and the key is the treatment of satellites' motion uncertainties and shapes, especially for ultra-close autonomous systems. In this paper, the zonotope-based reachable sets are utilized to propagate the uncertainties. For satellites with slender structures (such as solar panels), their shapes are simplified as cuboids which is a special class of zonotopes, instead of the classical sphere approach. The domains in position subspace influenced by the uncertainties and shapes are determined, and the relative distance is estimated to assess the safety of satellites. Moreover, with the approximation of the domains, the worst-case uncertainties for path constraints are determined, and a robust model predictive control method is proposed to deal with the line of sight and obstacle avoidance constraints. With zonotope representations of satellites, the proposed robust model predictive control is capable of handling the shapes of the satellite and obstacle simultaneously. Numerical simulations demonstrate the effectiveness of the proposed methods with an elliptic reference orbit. 1

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Kai, Xiong, Wei Chunling y Liu Liangdong. "Autonomous navigation for a group of satellites with star sensors and inter-satellite links". Acta Astronautica 86 (mayo de 2013): 10–23. http://dx.doi.org/10.1016/j.actaastro.2012.12.001.

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Liu, Song, Yingwu Chen, Lining Xing y Xiaojun Guo. "Time-dependent autonomous task planning of agile imaging satellites". Journal of Intelligent & Fuzzy Systems 31, n.º 3 (13 de agosto de 2016): 1365–75. http://dx.doi.org/10.3233/ifs-162202.

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McInnes, Colin R. "Autonomous ring formation for a planar constellation of satellites". Journal of Guidance, Control, and Dynamics 18, n.º 5 (septiembre de 1995): 1215–17. http://dx.doi.org/10.2514/3.21531.

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Long, Jun, Cong Li, Lei Zhu, Shilong Chen y Junfeng Liu. "An Efficient Task Autonomous Planning Method for Small Satellites". Information 9, n.º 7 (20 de julio de 2018): 181. http://dx.doi.org/10.3390/info9070181.

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Existing on-board planning systems do not apply to small satellites with limited onboard computer capacity and on-board resources. This study aims to investigate the problem of autonomous task planning for small satellites. Based on the analysis of the problem and its constraints, a model of task autonomous planning was implemented. According to the long-cycle task planning requirements, a framework of rolling planning was proposed, including a rolling window and planning unit in the solution, and we proposed an improved genetic algorithm (IGA) for rolling planning. This algorithm categorized each individual based on the compliance of individuals with a time partial order constraint and resource constraint, and designed an appropriate crossover operator and mutation operator for each type of individual. The experimental result showed that the framework and algorithm can not only respond quickly to observation tasks, but can produce effective planning programs to ensure the successful completion of observation tasks.

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30

Shim, Sun-Hwa, Sang-Young Park y Kyu-Hong Choi. "Autonomous Real-time Relative Navigation for Formation Flying Satellites". Journal of Astronomy and Space Sciences 26, n.º 1 (15 de marzo de 2009): 59–74. http://dx.doi.org/10.5140/jass.2009.26.1.059.

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31

Durand, J. M. "Satellite Navigation: GPS Inadequacies: Comparative Study into Solutions for Civil Aviation". Journal of Navigation 43, n.º 1 (enero de 1990): 8–17. http://dx.doi.org/10.1017/s037346330001376x.

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The Global Positioning System (GPS) will be an extremely high-performance satellite-based navigation system which is expected to provide a sole means air navigation service for most aeronautical flight phases. It will be particularly suitable for ‘en route’, ‘terminal’ and ‘non-precision approach’ phases, thus providing substantial savings on aircraft operating costs.However, GPS has three major disadvantages for civil aviation: (1) Insufficient system integrity, since satellites can transmit erroneous information for two hours before being repaired or neutralized. In such an event, the many simultaneous users of the satellite that has lost its integrity can derive false positions and remain unaware of the problem. (2) Availability constrained by the limited number of satellites. Users are then unable to obtain a position fix or else obtain a result with significantly degraded performance. (3) Deliberate spatio-temporal degradation (selective availability) of system performance, the characteristics of which are not fully known or defined.Many solutions to these problems have been put forward. One concept uses the redundancy of the GPS system itself (receiver autonomous integrity monitoring). Another set of solutions is based on complementary information from autonomous navigation equipment (altimeter, clock, inertial system) or external navigation systems already available or being developed (Omega, Loran-C, GLONASS). A third type of solution is to implement a system by which to monitor the status of the GPS satellites and broadcast the information to users.This paper reports on the different techniques put forward and uses different qualitative criteria (technical feasibility, cost, political independence, etc.) to assess their suitability for civil aviation applications. The comparison leads to the recommendation of a system to monitor the status of the GPS satellites and broadcast the information to users. The characteristics of such messages would be as similar as possible to those of GPS messages.

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32

TANG, ChengPan, XiaoGong HU, ShanShi ZHOU, JunYang PAN, Rui GUO, GuangMing HU, LingFeng ZHU, XiaoJie LI, Shan WU y Yan WANG. "Centralized autonomous orbit determination of Beidou navigation satellites with inter-satellite link measurements: preliminary results". SCIENTIA SINICA Physica, Mechanica & Astronomica 47, n.º 2 (22 de diciembre de 2016): 029501. http://dx.doi.org/10.1360/sspma2016-00355.

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33

Höyhtyä, Marko y Jussi Martio. "Integrated Satellite–Terrestrial Connectivity for Autonomous Ships: Survey and Future Research Directions". Remote Sensing 12, n.º 15 (4 de agosto de 2020): 2507. http://dx.doi.org/10.3390/rs12152507.

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An autonomous vessel uses multiple different radio technologies such as satellites, mobile networks and dedicated narrowband systems, to connect to other ships, services, and the remote operations center (ROC). In-ship communication is mainly implemented with wired technologies but also wireless links can be used. In this survey paper, we provide a short overview of autonomous and remote-controlled systems. This paper reviews 5G-related standardization in the maritime domain, covering main use cases and both the role of autonomous ships and that of people onboard. We discuss the concept of a connectivity manager, an intelligent entity that manages complex set of technologies, integrating satellite and terrestrial technologies together, ensuring robust in-ship connections and ship-to-outside connections in any environment. This survey paper describes the architecture and functionalities of connectivity management required for an autonomous ship to be able to operate globally. As a specific case example, we have implemented a research environment consisting of ship simulators with connectivity components. Our simulation results on the effects of delays to collision avoidance confirm the role of reliable connectivity for safety. Finally, we outline future research directions for autonomous ship connectivity research, providing ideas for further work.

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34

CODIK, ANDREW. "Autonomous Navigation of GPS Satellites: A Challenge For The Future". Navigation 32, n.º 3 (septiembre de 1985): 221–32. http://dx.doi.org/10.1002/j.2161-4296.1985.tb00906.x.

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35

Wen, Changxuan y Pini Gurfil. "Guidance, navigation and control for autonomous R-bar proximity operations for geostationary satellites". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, n.º 3 (13 de noviembre de 2016): 452–73. http://dx.doi.org/10.1177/0954410016638877.

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R-bar refers to the local vertical axis pointing radially upward in a satellite-fixed reference frame. Approaching a satellite along the R-bar, especially for rendezvous and docking to geostationary satellites, is advantageous in terms of safety considerations and flight time compared to other options. In this paper, a specialized study on autonomous R-bar proximity operations with respect to a geostationary target from a separation of several kilometers to a few hundreds of meters, commonly referred to as the closing phase, is carried out and a comprehensive solution for both attitude and orbit control in this scenario is proposed. An integrative design of the guidance, navigation, and control for R-bar proximity operations is presented. Impulsive R-bar hopping maneuvers are developed for the trajectory guidance. This method is shown to be passively safe and time efficient. The onboard sensors provide measurements of the line-of-sight, range to the target, attitude and angular velocity in the inertial frame. Due to the sensitivity of the sensor’s pointing in the far-range phase, a sliding mode attitude control law is introduced to align the optical axis with the line-of-sight to the target. Sensor measurements are fused and processed by an extended Kalman filter. Simulation results indicate that the proposed integrative guidance, navigation, and control algorithms are robust to uncertainties and noise, and can be used as a comprehensive solution for R-bar rendezvous and docking mission design during the closing phase.

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36

Feng, Shaojun, Washington Y. Ochieng, David Walsh y Rigas Ioannides. "A Highly Accurate and Computationally Efficient Method for Predicting RAIM Holes". Journal of Navigation 59, n.º 1 (15 de diciembre de 2005): 105–17. http://dx.doi.org/10.1017/s037346330500353x.

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Receiver Autonomous Integrity Monitoring (RAIM) is a method implemented within the receiver to protect users against satellite navigation system failures. For a receiver to execute a RAIM calculation, two conditions must be met: a minimum number of satellites and adequate satellite geometry. The non-existence of the minimum number of satellites (five) is referred to as a RAIM hole. Current regional and global RAIM availability studies use spatial (grid-based) and temporal sampling intervals driven by a trade-off between accuracy and computation workload. The implication of minimising computational load is that accuracy is compromised and potential RAIM holes remain un-sampled, with potential risk to safety. This paper proposes a direct and computationally efficient method (as opposed to the grid-based search approach) to predict RAIM holes. The method is based on the precise computation of satellite coverage (footprint) boundaries, the intersection points and analysis of the topology of the regions of intersection. Test results show that the proposed method is highly accurate and requires minimal computational load compared to the current approach.

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37

Adin, Iñigo, Paul Zabalegui, Alejandro Perez, Jaione Arrizabalaga, Jon Goya y Jaizki Mendizabal. "AIOSAT - Autonomous Indoor & Outdoor Safety Tracking System". Annual of Navigation 26, n.º 1 (1 de diciembre de 2019): 21–32. http://dx.doi.org/10.1515/aon-2019-0003.

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Abstract Even though satellite-based positioning increases rescue workers’ safety and efficiency, signal availability, reliability, and accuracy are often poor during fire operations, due to terrain formation, natural and structural obstacles or even the conditions of the operation. In central Europe, the stakeholders report a strong necessity to complement the location for mixed indoor-outdoor and GNSS blocked scenarios. As such, location information often needs to be augmented. For that, European Global Navigation Satellite System Galileo could help by improving the availability of the satellites with different features. Moreover, a multi-sensored collaborative system could also take advantage of the rescue personnel who are already involved in firefighting and complement the input data for positioning. The Autonomous Indoor & Outdoor Safety Tracking System (AIOSAT) is a multinational project founded through the Horizon 2020 program, with seven partners from Spain, Netherlands and Belgium. It is reaching the first year of progress (out of 3) and the overarching objective of AIOSAT system is to advance beyond the state of the art in tracking rescue workers by creating a high availability and high integrity team positioning and tracking system. On the system level approach, this goal is achieved by fusing the GNSS, EDAS/EGNOS, pedestrian dead reckoning and ultra-wide band ranging information, possibly augmented with map data. The system should be able to work both inside buildings and rural areas, which are the test cases defined by the final users involved in the consortium and the advisory board panel of the project

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38

Guerra, Edmundo, Antoni Grau, Yolanda Bolea y Rodrigo Munguia. "Enriching Low-Density Terrain Maps from Satellite with Autonomous Robots Data". Engineering Proceedings 6, n.º 1 (19 de mayo de 2021): 66. http://dx.doi.org/10.3390/i3s2021dresden-10157.

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Satellite imagery and remote sensoring have been used for some years in agriculture to create terrain maps for different soil features (humidity, vegetation index, etc.). Multichannel information provides lots of data, but with a big drawback: the low density of information per surface unit; that is, the multi-channeled pixels correspond to a large surface, and a fine characterization of the targeted areas is not possible. In this research, the authors propose the enrichment of such data by the use of autonomous robots that explore and sense the same targeted area of the satellite but yielding a finer detail of terrain, complementing and fusing both information sources. The sensory elements of the autonomous robots are in the visual spectrum as well as in the near-infrared spectrum, together with Lidar and radar information. This enrichment will provide a high-density map of the soil to the final user to improve crops, irrigation, seeding and other agricultural processes. The methodology to fuse data and create high-density maps will be deep learning techniques. The system will be validated in real fields with the use of real sensors to measure the data given by satellites and robots’ sensors.

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39

Abusali, P. A. M., B. D. Tapley y B. E. Schutz. "Autonomous Navigation of Global Positioning System Satellites Using Cross-Link Measurements". Journal of Guidance, Control, and Dynamics 21, n.º 2 (marzo de 1998): 321–27. http://dx.doi.org/10.2514/2.4238.

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40

Kong Xianghai, 孔祥海, 陈跃庭 Chen Yueting, 李奇 Li Qi, 冯华君 Feng Huajun y 徐之海 Xu Zhihai. "A Cloud-Top Height Detection Method for Autonomous Planning of Satellites". Acta Optica Sinica 35, n.º 7 (2015): 0728004. http://dx.doi.org/10.3788/aos201535.0728004.

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41

Lin-lin, Li y Sun Hui-xian. "A method of astronomical autonomous orbit and attitude determinations for satellites". Chinese Astronomy and Astrophysics 27, n.º 4 (octubre de 2003): 481–89. http://dx.doi.org/10.1016/s0275-1062(03)90072-5.

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42

Yoshida, Kazuya. "Space Robot Dynamics and Control: a Historical Perspective". Journal of Robotics and Mechatronics 12, n.º 4 (20 de agosto de 2000): 402–10. http://dx.doi.org/10.20965/jrm.2000.p0402.

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The Engineering Test Satellite VII (ETS-VII), developed and launched by National Space Development Agency of Japan (NASDA) on November 1997, has been successfully flown and carried out a lot of interesting orbital robotics experiments with a 2 meter-long, 6 DOF manipulator arm mounted on this un-manned spacecraft. The ETS-VII should be noted as one of remarkable outcomes of research effort on space robots, particularly characterized as an orbital free-flying robot which concept was brought in early 80s. This paper provides a historical overview and a summary of the ideas around dynamics and control proposed for free-flying space robots, then highlights key control technologies recently tested and verified on ETS-VII. The ETS-VII flight mission is an important milestone, but not a goal. The goal will be robotic service to satellites in orbits, including an emerging number ofcommunication satellites spreading out to the low-earth orbital networks or constellations. In a mission sequence of autonomous satellite capture, what part is now verified and what is left over for future researchxare also discussed.

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43

Haddadi Amlashi, H., F. Samadzadegan, F. Dadrass Javan y M. Savadkouhi. "COMPARING THE ACCURACY OF GNSS POSITIONING VARIANTS FOR UAV BASED 3D MAP GENERATION". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B1-2020 (6 de agosto de 2020): 443–49. http://dx.doi.org/10.5194/isprs-archives-xliii-b1-2020-443-2020.

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Abstract. GNSS stands for Global Navigation Satellite System and is the standard generic term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage. The advantage of having access to multiple satellites is accuracy, redundancy, and availability at all the times. Though satellite systems do not often fail, if one fails GNSS receivers can pick up signals from other systems. If the line of sight is obstructed, having access to multiple satellites is also a benefit. GPS (Global Positioning System, USA), GLONASS (Global Navigation Satellite System, Russia), BeiDou (Compass, China), and some regional systems are positioning systems that are usually used. In recent years with the development of the UAVs and GNSS receivers, it is possible to manage an accurate PPK (Post Processing Kinematic) networks with a GNSS receiver mounted on a UAV to achieve the position of images principal points WGS1984 and to reduce the need for GCPs. But the most important challenge in a PPK task is, which a combination of different GNSS constellations would result in the most accurate computed position in checkpoints. For this purpose, this study focused on a PPK equipped UAV to map an open pit (Golgohar mine near Sirjan city). For the purpose, different combination of GPS, GLONASS and BeiDou used for position computed. Results are plotted and compared and found out having access to multiple constellations while doing a PPK task would bring higher accuracies in building photogrammetric models although it may cause some random error due to the higher values of noise while the number of the satellites increases.

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44

Yu, Feng, Yi Zhao y Yanhua Zhang. "Pose Determination for Malfunctioned Satellites Based on Depth Information". International Journal of Aerospace Engineering 2019 (11 de junio de 2019): 1–15. http://dx.doi.org/10.1155/2019/6895628.

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Autonomous on-orbit servicing is the future space activity which can be utilized to extend the satellite life. Relative pose estimation for a malfunctioned satellite is one of the key technologies to achieve robotic on-orbit servicing. In this paper, a relative pose determination method by using point cloud is presented for the final phase of the rendezvous and docking of malfunctioned satellites. The method consists of three parts: (1) planes are extracted from point cloud by utilizing the random sample consensus algorithm. (2) The eigenvector matrix and the diagonal eigenvalue matrix are calculated by decomposing the point cloud distribution matrix of the extracted plane. The eigenvalues are utilized to recognize rectangular planes, and the eigenvector matrix is the attitude rotation matrix from the sensor to the plane. The solution of multisolution problem is also presented. (3) An extended Kalman filter is designed to estimate the translational states, the rotational states, the location of mass center, and the moment-of-inertia ratios. Because the method only utilizes the local features without observing the whole satellite, it is suitable for the final phase of rendezvous and docking. The algorithm is validated by a series of mathematical simulations.

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45

Wang, Zhipeng, Wei Shao, Rui Li, Dan Song y Tinglin Li. "Characteristics of BDS Signal-in-Space User Ranging Errors and Their Effect on Advanced Receiver Autonomous Integrity Monitoring Performance". Sensors 18, n.º 12 (18 de diciembre de 2018): 4475. http://dx.doi.org/10.3390/s18124475.

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Signal-In-Space User Range Errors (SIS UREs) are assumed to be overbounded by a normal distribution with a standard deviation represented by the User Range Accuracy (URA). The BeiDou Navigation Satellite System (BDS) broadcast URA is not compatible with the historical SIS URE performance that affects the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) False Alert Probability (Pfa) and availability evaluation. This study compares the BDS broadcast and precise ephemeris from 1 March 2013 to 1 March 2017 to obtain SIS UREs. Through analyzing the statistical characteristics of the SIS UREs, we obtain the standard deviation σURE for the accuracy and continuity and σURA used for the integrity of the SIS UREs. The results show that the broadcast σURA of 2 m cannot completely overbound SIS UREs for all BDS satellites, but the σURA of 2.4 m can. Then, we use the σURA of 2.4 m to evaluate the ARAIM Pfa and availability. The results show that the Pfa may increase to 2 × 10−5 and exceed its limit by an order of magnitude. We also consider the differences between the SIS UREs of Geostationary Earth Orbit (GEO), Inclined Geo-Synchronous Orbit (IGSO), and Medium Earth Orbit (MEO). The results indicate that all Pfa values calculated by the computed σURE are less than the Pfa in the Integrity Support Message (ISM) for the worst-performing GEO satellite. The approximately 55% Pfa calculated by the computed σURE is less than the Pfa in ISM for the worst-performing IGSO satellite. Most Pfa values calculated by the computed σURE is less than the Pfa in the ISM for the worst-performing MEO satellite. For BDS satellites, the Pfa is mainly affected by σURE. When the σURA of 2.4 m is used to evaluate the availability, the computed availability is lower than the availability calculated by the broadcast σURA/σURE and the greatest degradation can reach 25%.

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46

Holdaway, R. "A Program for the Autonomous Ground Station Control of Small Scientific Satellites". IFAC Proceedings Volumes 29, n.º 1 (junio de 1996): 7378–83. http://dx.doi.org/10.1016/s1474-6670(17)58873-4.

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47

Li, Yong y Ai Zhang. "Observability analysis and autonomous navigation for two satellites with relative position measurements". Acta Astronautica 163 (octubre de 2019): 77–86. http://dx.doi.org/10.1016/j.actaastro.2019.02.030.

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48

Xinlong, Wang, Wang Bin y Li Hengnian. "An autonomous navigation scheme based on geomagnetic and starlight for small satellites". Acta Astronautica 81, n.º 1 (diciembre de 2012): 40–50. http://dx.doi.org/10.1016/j.actaastro.2012.07.013.

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49

Shang, Lin, Guohua Liu, Rui Zhang y Guotong Li. "An information fusion algorithm for integrated autonomous orbit determination of navigation satellites". Acta Astronautica 85 (abril de 2013): 33–40. http://dx.doi.org/10.1016/j.actaastro.2012.12.007.

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50

Li, Lincheng, Jingrui Zhang, Shuge Zhao, Rui Qi y Yanyan Li. "Autonomous onboard estimation of mean orbital elements for geostationary electric-propulsion satellites". Aerospace Science and Technology 94 (noviembre de 2019): 105369. http://dx.doi.org/10.1016/j.ast.2019.105369.

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