Digital micro-thruster arrays can be used for special missions of micro/nano-satellites with the requirements of high precision and small impulse.This paper presents a novel control allocation algorithm for the digita...Digital micro-thruster arrays can be used for special missions of micro/nano-satellites with the requirements of high precision and small impulse.This paper presents a novel control allocation algorithm for the digital micro-thruster array,namely status graph based control allocation(SGBCA)algorithm,which aims at finding the optimal micro thrusters combination scheme to realize the sequential control synthesis for micro/nano-satellite during real-time orbit control tasks.A mathematical model is set up for the control allocation of this multivariate over-actuated system.Through dividing thrusters into disjoint segments by offline calculation and combining segments dynamically online to provide a sequence of the required impulse for the micro/nano-satellite,the time complexity of the control allocation algorithm decreases significantly.All levels of impulse can be generated by the digital micro thruster arrays and the service life of the arrays can be extended using the segment converting strategy proposed in this paper.The simulation indicates that the algorithm can satisfy the requirements of real-time orbit control for micro/nano-satellites.展开更多
At an accelerating development pace, Hicro-Nano Satellite technology has become one of the most ac- tive research topics in the current aerospace field. Its applications have been extended from engineering education a...At an accelerating development pace, Hicro-Nano Satellite technology has become one of the most ac- tive research topics in the current aerospace field. Its applications have been extended from engineering education and technology demonstration into various other fields, such as communication, remote sensing, navigation and scientific experiments just to name a few, In this paper issues raised on Micro/Nano-Satellites in recent news are reviewed and the opportunities and challenges confronting Micro/Nano-Satellites are analyzed. Then the Plicro/nano-Satellites of Na- tional University of Defense Technology, （NUDT） are briefly introduced. Finally, some suggestions on the development of Micro/Nano-Satellites in the future are proposed.展开更多
＂Tian Tuo 1＂ （TT-1） nano-satellite is the first single-board nano-satellite that was suc- cessfully launched in China. The main objective of TT-1 is technology demonstration and scientific measurements. The satell...＂Tian Tuo 1＂ （TT-1） nano-satellite is the first single-board nano-satellite that was suc- cessfully launched in China. The main objective of TT-1 is technology demonstration and scientific measurements. The satellite carries out the significant exploration of single-board architecture fea- sibility validation, and it is tailored to the low-cost philosophy by adopting numerous commercial- off-the-shelf （COTS） components. The satellite is featured with three-axis stabilization control capability. A pitch bias momentum wheel and three magnetic coils are adopted as control actuators. The sun sensors, magnetometers and a three-axis gyro are employed as the measurement sensors. The quaternion estimator （QUEST） and unscented Kalman filter （UKF） method are adopted for the nano-satellite attitude determination. On-orbit data received by ground station is conducted to analysis the performance of attitude determination and control system （ADCS）. The results show that the design of ADCS for TT-1 is suitable, robust and feasible.展开更多
文摘Digital micro-thruster arrays can be used for special missions of micro/nano-satellites with the requirements of high precision and small impulse.This paper presents a novel control allocation algorithm for the digital micro-thruster array,namely status graph based control allocation(SGBCA)algorithm,which aims at finding the optimal micro thrusters combination scheme to realize the sequential control synthesis for micro/nano-satellite during real-time orbit control tasks.A mathematical model is set up for the control allocation of this multivariate over-actuated system.Through dividing thrusters into disjoint segments by offline calculation and combining segments dynamically online to provide a sequence of the required impulse for the micro/nano-satellite,the time complexity of the control allocation algorithm decreases significantly.All levels of impulse can be generated by the digital micro thruster arrays and the service life of the arrays can be extended using the segment converting strategy proposed in this paper.The simulation indicates that the algorithm can satisfy the requirements of real-time orbit control for micro/nano-satellites.
文摘At an accelerating development pace, Hicro-Nano Satellite technology has become one of the most ac- tive research topics in the current aerospace field. Its applications have been extended from engineering education and technology demonstration into various other fields, such as communication, remote sensing, navigation and scientific experiments just to name a few, In this paper issues raised on Micro/Nano-Satellites in recent news are reviewed and the opportunities and challenges confronting Micro/Nano-Satellites are analyzed. Then the Plicro/nano-Satellites of Na- tional University of Defense Technology, （NUDT） are briefly introduced. Finally, some suggestions on the development of Micro/Nano-Satellites in the future are proposed.
文摘＂Tian Tuo 1＂ （TT-1） nano-satellite is the first single-board nano-satellite that was suc- cessfully launched in China. The main objective of TT-1 is technology demonstration and scientific measurements. The satellite carries out the significant exploration of single-board architecture fea- sibility validation, and it is tailored to the low-cost philosophy by adopting numerous commercial- off-the-shelf （COTS） components. The satellite is featured with three-axis stabilization control capability. A pitch bias momentum wheel and three magnetic coils are adopted as control actuators. The sun sensors, magnetometers and a three-axis gyro are employed as the measurement sensors. The quaternion estimator （QUEST） and unscented Kalman filter （UKF） method are adopted for the nano-satellite attitude determination. On-orbit data received by ground station is conducted to analysis the performance of attitude determination and control system （ADCS）. The results show that the design of ADCS for TT-1 is suitable, robust and feasible.
