To achieve rapid and stable detumbling of a space noncooperative satellite, an adaptive variable admittance control method for the manipulator is proposed verified through simulation study ground experiment. The block diagram presented, compliant model established. controller includes fixed in task space, pose compensator grasping point on docking ring, damping regulator based joint angular velocity, stability proven by Lyapunov method. Subsequently, advantage comparison with other methods,...

Tether-nets in space applications are flexible capture systems for removing debris. A new, low-mass, rectangular tether-net deployed by ten towing blocks is proposed this paper the purpose of capturing main body satellites. The dynamic model a during deployment process was established. accuracy simulation validated comparing it with on-ground experiments. In addition, influence block mass and launch speed on maximum area lengths long side short were systematically analyzed. results show that...

In this article, a new method to design multibeam antenna based on phase-gradient metasurface (MS) is proposed and demonstrated through two cases of single source multisource. The basic idea employ the feeding operating in high-order TM20 (TM02) mode generate split beams. Then, by loading an F–P cavity MS, narrow main lobe obtained. Also, gain raised sidelobe level (SLL) cut down. addition, for single-source antenna, impedance matching improved further enhanced holes. Moreover, adding...

In this paper, a multi-beam antenna based on annular slot and uneven metasurface is proposed. Through using the formed by patches with different dimensions as radiator, beam focus direction of θ = 32°. As result, gain improved. Furthermore, employing compound double ground plane, further raised backward radiation reduced. The realized has dimension 65 × 4.862 mm3 (equal to 1.08λ0 0.08λ0). results indicate that proposed can operate from 4.95 5.42 GHz. case four ports are excited respectively,...

Abstract Rice‐animal co‐culture (RAC) systems are an integrated farming approach to mitigate the diverse challenges facing food system. Studies of production potential and ecological mechanisms RAC have demonstrated natural advantages over traditional systems. The quantification promotion at regional global scales, however, remains unclear. Writing in Earth's Future, Cui et al. (2023, https://doi.org/10.1029/2022EF002984 ) comprehensively assessed system identified benefits using a...

Space instable target simulator (SITS) is a vital actuator for ground verification of on-orbital capture technology, the motion performance which directly affects simulation credibility. Different delays reduce stability SITS and ultimately lead to its divergence. In order achieve high fidelity simulation, impact force measurement delay, discrete control cycle, response delay on analyzed firstly. Then, dynamic equation transfer function identification model hybrid constructed, necessary...

The space instable target simulator (SITS) is a vital actuator for ground verification of on-orbital capture technology, the motion performance which directly affects simulation credibility. Different delays reduce stability SITS and ultimately lead to its divergence. In order achieve high-fidelity simulation, impacts force measurement delay, discrete control cycle, response delay on are analyzed first. Then, dynamic equation transfer function identification model hybrid constructed,...

<title>Abstract</title> To achieve rapid and stable detumbling of a space non-cooperative satellite, an adaptive variable admittance control method for the manipulator is proposed verified through on-ground experiment. The composition designed hardware-in-the-loop verification platform are first demonstrated, on this basis, principle elaborated. Subsequently, block diagram presented, compliant model kinematic established. controller includes fixed in task space, pose compensator grasping...

In order to cope with all kinds of emergencies on the freeway and improve emergency response capability system, road network is quantitatively assessed. Based system resilience theory, a assessment index constructed from three aspects: resistance capability, adaptive recovery optimization capability. The concept cloud model introduced, traditional hierarchical analysis scalar theory modified show randomness, fuzziness dispersion evaluation numerical characteristics expectation, entropy super...

In this paper, a multi-beam antenna based on uneven matasurface is propoesd. Beamforming achieved by single layer metasurface placed above the radiating element. By employing metasurface, beam becomes more concentrated. The results show that radiates four beams pointing at (θ, φ) = (20°, 0°), 90°), 180°), 270°). working bandwidth of 5.86~6.41 GHz (0.55 GHz), and gain reaches 9.12 dBi.

In this paper, a dual-frequency dual-beam antenna loaded with metasurface is proposed. Firstly, the feeding unit composed of two printed dipole used to provide excitation. And then, by loading periodically arranged square rings, beams steered different directions are realized and wider working frequency bands obtained. At same time, beam gains improved. The results show that resonant frequencies at 57 GHz 66 GHz, corresponding maximum radiation pointing (φ,θ) = (164°, 90°), (196°, 90°) (φ,...

This paper proposes a multi-beam antenna based on square ring slot and metasurface. Steering the beam in elevation plane is realized by placing metasurface above radiating element. And non-uniform characteristics of helps to make more concentrated. Also, gain proposed improved increasing number slot. The results show that radiates four beams pointing at (θ, ϕ) = (30°, 0°), 90°), 180°), 270°). -10 dB impedance bandwidth 3.94~5.50 GHz (1.56 GHz), 9.56 dBi.