A high‐fidelity multibody‐system dynamic model of the looped tether transportation system (L‐TTS) is proposed in this study to study its large deformation as well as large overall motion. The absolute nodal coordinate formulation (ANCF)‐based gradient‐deficient beam element is employed to establish the accurate model of the two flexible tethers subject to large deformations. The relative movement of climbers along tethers is described by using the sliding joint model based on ANCF. To reduce the collision risks between tethers and climbers, two libration suppression strategies, namely, the decelerated motion of climbers relative to tethers and multiple climbers per tether are investigated in this study. Several numerical simulations not only validate the effectiveness of the two strategies in reducing the collision risks between climbers and tethers, the overall librations of L‐TTS, and the magnitudes of the longitudinal elastic force of tethers, but also verify the good performance of the high‐fidelity model proposed in this study for dynamic simulation of the L‐TTS in microgravity conditions.

Power-form nonlinear contact force models are widely adopted in relatively moving parts of macro (e.g., rolling bearings considering Hertzian contact restoring force between rolling elements and bearing raceways) or micro (e.g., the micro cantilever probe system of atomic force microscopy) scale mechanical systems, and contact resonance could cause serious problems of wear, contact fatigue, vibration, and noise, which has attracted widespread attention. In the present paper, the softening/hardening stiffness characteristics of continuous and one-sided contact power-form nonlinear spring models are addressed, respectively, by the analysis of the monotone features of resonant frequency-response skeleton lines. Herein, the period-n solution branch and its stability characteristics are obtained by the harmonic balance and alternating frequency/time domain (HB–AFT) method and Floquet theory. Compared with previous studies, this paper will furtherly clarify the influences of externally normal load, the power form exponent term, and excitation amplitude on the softening/hardening stiffness characteristics of general power-form spring systems. In addition, for a power-form system with a one-sided contact, the phenomena of primary and super/sub-harmonic hysteretic resonances inducing period-doubling, folding bifurcation, the coexistence of multiple solutions are demonstrated. Besides, it gives the evolution mechanism of two types of intermittency chaos in a one-sided contact system. The overall results may have certain basic theoretical significance and engineering values for the control of vibration and noise in contact mechanical systems.

This paper studied the dynamic characteristics of electrodynamic tethered satellite with consideration of coupled multiphysics field for orbital boost maneuver by a fully insulated electrodynamic tether (EDT). We proposed a simplified analytical nonlinear current–voltage circuit method based on the Parker–Murphy model to evaluate the real-time electric current-carrying tether. Furthermore, the performances of orbital boost maneuver by a fully insulated electrodynamic tether is investigated. This current–voltage model is influenced by the electron density, the intensity of Earth’s magnetic field and the space plasma temperature. The hollow plasma contactor located on the sub-satellite to attract the electrons from the ambient plasma. An on-board power supply is adopted to change the direction of electric current for boosting the system. The direction of electric current in tether is from main-satellite to sub-satellite. The efficiency of orbital boost maneuver is compared with different sizes of anodic contactors and the given voltage of power supply. The simulation results showed that electric current is easily affected by the fluctuation of electron density, the Earth’s magnetic field and plasma temperature. The electrodynamic tether system can stable boost its orbit altitude from 400 to 1200 km in four cases by a fully insulated electrodynamic tether.

In recent years, flexible structures composed of cables, plates and shells, such as rotors and solar sails that rotate around a fixed axis have been widely used in aerospace, energy and other industrial fields. Traditional structural dynamics or multi-flexible dynamics modeling methods based on structural small deformation assumptions cannot accurately describe the nonlinear dynamics of flexible structures undergoing large-scale rotation. The Absolute Nodal Coordinate Formulation (ANCF) can accurately describe the flexible multi-body system with both large rigid motions and large deformation. Such flexible structures, while undergoing a wide range of rotational motions, are accompanied by structural vibrations that are excited by unbalanced centrifugal forces, aerodynamic forces, etc., resulting in very complex dynamic behaviors. Therefore, it is of great scientific significance and application value to dynamically model and predict the dynamic response of such flexible structures with a wide range of rotational motions. In this paper, the cylindrical shell element of ANCF proposed by Liu et al. which can realize efficient calculation is briefly introduced. The analytical expressions of elastic force and Jacobin matrix of this shell element are given. Modal analysis of shell structures modeled by ANCF cylindrical shell element and rotating around a fixed axis is studied. The effect of curvature and angular velocities on the modal of shell structures is validated.