To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, ne...To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, net, and target (i.e., GEO debris) constitute a rig- id-flexible coupled tethered combination system (TCS), and subsequently the system is transported to the graveyard orbit by a thruster equipped on the tug. This paper attempts to study the dynamics of tether-tugging leorbiting after net capture. The net is equivalent to four flexible bridles, and the tug and target are viewed as rigid bodies. A sophisticated mathematical model is developed, taking into account the system orbital motion, relative motion of two spacecraft and spacecraft attitude motion. Given the complexity of the model, the numerical method is adopted to study the system dynamics characteristics. Particular attention is given to the investigation of the possible risks such as tether slack, spacecraft collision, tether rupture, tether-tug intertwist and destabilizing of the rug's attitude. The influence of the initial conditions and the magnitudes of the thrust are studied.展开更多
Recent studies have indicated that hypervelocity impacts by meteoroids and space debris can induce spacecraft anomalies. However, the basic physical process through which space debris impacts cause anomalies is not en...Recent studies have indicated that hypervelocity impacts by meteoroids and space debris can induce spacecraft anomalies. However, the basic physical process through which space debris impacts cause anomalies is not entirely clear. Currently, impact-generated plasma is thought to be the primary cause of electrical spacecraft anomalies, while the effects of impact-generated mechanical damage have rarely been researched. This paper presents new evidence showing that impact-generated mechanical damage strongly influences electrostatic discharge. Hypervelocity impact experiments were conducted in a plasma drag particle accelerator, using particles with diameters of 200–500 ?m and velocities of 2–7 km/s. The impact-generated mechanical damage on a specimen surface was measured by a stereoscopic microscope and 3D Profilometer and it indicated that microscopic irregularities around the impact crater could be responsible for local electric field enhancement. Furthermore, the influence of impact-generated mechanical damage on electrostatic discharge was simulated in an inverted potential gradient situation. The experimental results show that the electrostatic discharge voltage threshold was significantly reduced after the specimen was impacted by particles.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11272345)
文摘To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, net, and target (i.e., GEO debris) constitute a rig- id-flexible coupled tethered combination system (TCS), and subsequently the system is transported to the graveyard orbit by a thruster equipped on the tug. This paper attempts to study the dynamics of tether-tugging leorbiting after net capture. The net is equivalent to four flexible bridles, and the tug and target are viewed as rigid bodies. A sophisticated mathematical model is developed, taking into account the system orbital motion, relative motion of two spacecraft and spacecraft attitude motion. Given the complexity of the model, the numerical method is adopted to study the system dynamics characteristics. Particular attention is given to the investigation of the possible risks such as tether slack, spacecraft collision, tether rupture, tether-tug intertwist and destabilizing of the rug's attitude. The influence of the initial conditions and the magnitudes of the thrust are studied.
文摘Recent studies have indicated that hypervelocity impacts by meteoroids and space debris can induce spacecraft anomalies. However, the basic physical process through which space debris impacts cause anomalies is not entirely clear. Currently, impact-generated plasma is thought to be the primary cause of electrical spacecraft anomalies, while the effects of impact-generated mechanical damage have rarely been researched. This paper presents new evidence showing that impact-generated mechanical damage strongly influences electrostatic discharge. Hypervelocity impact experiments were conducted in a plasma drag particle accelerator, using particles with diameters of 200–500 ?m and velocities of 2–7 km/s. The impact-generated mechanical damage on a specimen surface was measured by a stereoscopic microscope and 3D Profilometer and it indicated that microscopic irregularities around the impact crater could be responsible for local electric field enhancement. Furthermore, the influence of impact-generated mechanical damage on electrostatic discharge was simulated in an inverted potential gradient situation. The experimental results show that the electrostatic discharge voltage threshold was significantly reduced after the specimen was impacted by particles.