The rapid development of Low Earth Orbit (LEO) mega constellations has significantly contributed to several aspects human scientific progress, such as communication, navigation, and remote sensing. However, unrestrained deployment also strained orbital resources increased spacecraft congestion in LEO, which seriously affects the safety in-orbit operations many space assets. For long-term sustainable activities LEO regions, environment stability must be maintained using more rational...

In this paper, a path planning algorithm for multi-arm space robot is proposed. The capable of maneuvering on the exterior large station. Based maneuver strategy, continuous and smooth trajectories manipulator end effectors are first determined via polynomial interpolation method. Then, kinematics describing relation between effector joint angles as well platform formulated. A Moore–Penrose pseudoinverse solution calculated to describe motion manipulators, particularly, considering...

The stationary hovering characteristic of elliptical orbit was analyzed in two cases this paper. In the first case, short-time at R-bar and V-bar were by calculating drift coefficient relative acceleration. approximate uncontrolled region obtained computing variation with orbital elements (semimajor axis, eccentricity, true anomaly). second long-time velocity increment costs an period using open-loop controller. Analytical numerical analysis showed that it is easier for high low eccentricity...

The control moment gyroscope (CMG) is used as the actuator of attitude for modern satellites. Because static and dynamic rotor imbalances installation errors, it becomes one main vibration sources on a satellite. To provide quiet environment optical payloads, CMG disturbance characteristics due to errors are analyzed, application remote sensing satellites discussed. In first step, we construct model according Newton-Euler approach, taking into consideration. This analyzed in detail, axial...

This paper presents a novel control strategy for attitude and vibration suppression of flexible spacecraft. A set moment gyroscopes are distributed on the structure spacecraft to provide torques. The interactions between flexibilities incorporated in equations motion. nonlinear controller is first formulated determine desired input large angle three-axis maneuvers suppression. Then, steering law designed obtain gimbal commands gyroscopes. For small error stabilization, simple adaptive...

A new vibration control strategy is presented to realize rapid attitude maneuvers and stabilization for a spacecraft with flexible appendages. This combines the command input shaping technique of passive isolation sources. The analytical dynamic model moment gyroscopes, system, appendages constructed. Based on this proportion differentiation (PD) law, modal parameters closed-loop system are calculated, multiple mode shapers designed. Several simulations comparative studies have shown that...

Spin-2 ultralight dark matter (ULDM) is a viable candidate and it can be constrained using gravitational wave (GW) observations. In this paper, we investigate the detectability of spin-2 ULDM by space-based GW interferometers. By considering direct coupling between ordinary matter, derive corresponding response functions sensitivity curves for various time-delay interferometry channels calculate optimal future millihertz detectors. Our results demonstrate that detectors place stringent...

In order to recovery geostationary orbit environment, a Space Tether-Net system, which is used capture and remove the retired or malfunction satellites graveyard orbit, proposed designed in this paper. Firstly debris introduced based on DISCOS database, then mission sequence by using space tether net system designed, after that detailed descriptions about tool are presented illustrate advantages of flexible net. Finally key subsystems, including Data Management Compute, Attitude & Orbital...

The objective of this paper is to find the minimum-fuel transfer needed for servicing client geostationary satellites while considering perturbations that have been neglected in previous studies. effect Earth's triaxiality on semimajor axis and longitude derived by method averaging used designing a two-impulse planar phasing maneuver. maneuver then extended three-impulse matching eccentricity. inclination variation due lunisolar modeled determine eliminating normal direction excursion. Then,...

This brief is devoted to the power-constrained low-thrust optimal control problem (OCP). First, a general model for class of power constraints proposed by defining piecewise smooth function, which describes discontinuities system. Subsequently, recursive smoothing function generalized discontinuous terms leading family OCPs, whose solutions converge solution OCP. The distinguished feature that variations bound, caused constraints, are embedded into and retrieved gradually. Consequently,...

The space tether-net system for on-orbit capture is proposed in this paper. In order to research the dynamic behaviors during deployment, both free and nonfree deployment dynamics circular orbit are developed; motion with respect Local Vertical Horizontal frame also researched analysis simulation. results show that case of net follows curve trajectories due relative perturbation, initial velocities planned by state transformation equations static floating target captures; non-free undergoes...

An improved method based on special-point-based maneuvers is presented to realize autonomous rendezvous phasing in a near-circular orbit. The segment divided into three subphases (the initial subphase, the natural and adjusting subphase) according relationship between orbital phase angle semimajor axis difference chaser target. Maneuver orbit done subphase. In two spacecraft reduced naturally due difference, then maneuver implemented. step by satisfy close approaches requirement. addition...