Design Of Microsatellite Micro-Thrust System For Ultra-Low Orbit Maintenance And Micro-Force Measurement

Ultra-low orbit calibration microsatellite has unique advantages in applications such as military reconnaissance and scientific exploration,because of its lower-altitude orbit,it has better economic benefits and broader application prospects.In the meantime,the operational life span of ultra-low-orbit microsatellite is shorter than the traditional low-orbit satellite's life,because it is subject to dozens of orders of magnitude higher atmospheric resistance when it is in lower orbits.Therefore,in order to prolong the operation life span,it is necessary to implement orbit maintenance control for ultra-low-orbit microsatellites,and the push-based micro-pushing is more suitable for the maintenance control of microsatellites with high specific impulse,no fuel consumption and low price.In this paper,based on the orbit maintenance of ultra-low-orbit microsatellites,the new vacuum arc thruster was applied to provide continuous and small control of ultra-low-orbit microsatellites and the micro-forces were calibreted.The main research contents of this paper include:Firstly,under different perturbation factors the orbital drift is analyzed in the ultra-low-orbit environment.Based on the Gaussian perturbation equation of motion of satellite orbits,under the action of ultra-low-orbit atmospheric drag and J2 perturbation factors,the orbital variation characteristics are analyzed by numerical solution.The calculation results show that the atmospheric resistance make the orbital height decay rapidly under ultra-low rail conditions.Given the attenuation rate,it provides the theoretical basis and input conditions for the micro-push-based ultra-low orbital orbit maintenance.Secondly,based on vacuum arc micro-thrust,an ultra-low orbit maintenance strategy is proposed.Under the condition of J2 perturbation and atmospheric resistance,the continuous micro-thrust of vacuum arc micro-push is proposed to compensate the power;due to the limited life of a single micro-push switch and the insufficient thrust,this paper also designs the configuration of the micro-thrust array to improve the reliability of the thrust system and to increase the thrust.The simulation analysis shows that by designing a reasonable layout,the vacuum arc micro-push can be applied to the precise orbit maintenance control of ultra-low-orbit micro satellites stably and reliably.Thirdly,a micro-thrust measurement system capable of measuring 10?N was designed and built.It is vital to the precise orbit maintenance based on micro-push that single thrust is calibrated accurately.In order to verify the reliability of the vacuum arc micro-push array to maintain the power demand of the ultra-low track,based on gravity complex pendulum a micro-thrust measurement system is designed and built.According to the accuracy of micro-force measurement and environmental requirements,the overall scheme software and hardware design of the system based on pendulum as the measurement principle is carried out.Finally,the actual measurement and analysis of micro-thrust measurement system are completed.The test system has a simple principle and the difficulty lies in the processing of measurement data.In order to improve the measurement accuracy,the test system has completed the complete frequency test,the recovery coefficient calibration experiment and the standard quality verification experiments,and the measuring process and steps are sorted out,so that the micro force measurement accuracy reaches the order of 10?N,which fully meets the micro-push test requirements.Further,the practicality of the micro-thrust measurement system is promoted.