Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised m...
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Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.
Planet rovers are becoming more and more crucial as deep space exploration missions develop. Accurate terrain segmentation can increase the rovers' capacity for independent detection. At present, the task of Mars ...
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In order to obtain gravity field data with high-precision, ultra quiet control should be applied in the attitude control system to reduce the influence of micro vibration caused by attitude control, since the measurem...
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Onboard initial relative orbit determination (IROD) by using angle measurements is the key to space Situational Awareness. The camera offset measurement method is one of the most used IROD methods when only the angle ...
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An estimation algorithm of population feature distribution (EPFD) is proposed to improve the completion and imaging quality of imaging constellation observation tasks. Firstly, the observation task constraints and on-...
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With development of aerospace industry, the mass of liquid fuel carried by spacecraft is also increasing in order to complete more complex space exploration missions, such as on-orbit refueling and space debris remova...
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With development of aerospace industry, the mass of liquid fuel carried by spacecraft is also increasing in order to complete more complex space exploration missions, such as on-orbit refueling and space debris removal. And there is large liquid fuel consumption when spacecraft completes attitude and orbit maneuver, which greatly increases the nonlinearity and uncertainty of spacecraft dynamics and brings great challenges to spacecraft attitude maneuver control. Considering that during attitude maneuver, the control torque is easy to stimulate the liquid slosh, which will affect the attitude control performance and even lead to instability of the system. So it is necessary to constrain the angular velocity during attitude maneuver. In this paper, we consider the large angle attitude maneuver control of liquid-filled spacecraft system. Because of the consumption of liquid fuel, then the mass property of system is unknown and slowly time varying. So a novel finite-time attitude maneuver control law based on barrier Lyapunov function (BLF) and backstepping method in the presence of unknown, time varying system dynamics and angular velocity constraint, which aims at avoidance of violent liquid slosh, is proposed in this paper. Firstly, the sloshing liquid in a partially filled tank carried by the spacecraft is equivalent to a sloshing slug - a sphere of uniform density with a variable radius, and the rigid-liquid coupling dynamic equations with unknown parameters of the spacecraft are deduced by using the law of conservation of moment of momentum. Secondly, a finite-time prescribed performance function (FTPPF) is proposed to guarantee the convergence of spacecraft attitude error to zero within the setting time, with the help of FTPPF and the angular velocity constraint, a time-varying BLF and a logarithmic BLF are proposed correspondingly. Furthermore, a backstepping control law is designed for the spacecraft attitude maneuver based on augmented Lyapunov functions, mean
Cognitive navigation, a high-level and crucial function for organisms' survival in nature, enables autonomous exploration and navigation within the environment. However, most existing works for bio-inspired naviga...
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With the popularity of drones, incidents that threaten public safety caused by drones occur more frequently. In drone control and countermeasures scenarios, it is needed to further identify drones of the same type bas...
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To mitigate the threat of asteroid impact on life on Earth, non-nuclear kinetic energy high-speed impact has been identified as the most viable strategy. To ensure accurate impact on the asteroid's center of mass ...
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The autonomous mission planning problem of space targets tracking with multi-satellite is studied in this paper. For effective evaluation of different candidate tracking resource combinations, a tracking performance e...
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