Journal of Systems Engineering and Electronics ›› 2018, Vol. 29 ›› Issue (3): 618-624.doi: 10.21629/JSEE.2018.03.19

• Software Algorithm and Simulation • Previous Articles     Next Articles

Modeling of disturbance torque in an aerostatic bearings-based nano-satellite simulator

Yanfang LIU*(), Mingying HUO(), Naiming QI()   

  • Received:2017-04-17 Online:2018-06-28 Published:2018-07-02
  • Contact: Yanfang LIU E-mail:liu-yanfang@hotmail.com;huomingying123@163.com;qinmok@163.com
  • About author:LIU Yanfang was born in 1986. He received his B.S. degree in aircraft design engineering from Harbin Engineering University in 2008 and Ph.D. degree in aeronautical and astronautical science and technology from Harbin Institute of Technology in 2013. He visited and studied in the area of nano-positioning based on piezoelectric actuators in York University in 2013. He is currently an associate professor in Harbin Institute of Technology. His research interests are spacecraft simulator technique and system, dynamics, control and navigation of spacecraft, mechanical and electrical integration and ground simulation of spacecraft, simulation of low gravity environment, smart materials and structures, and shape and vibration control of flexible systems. E-mail: liu-yanfang@hotmail.com|HUO Mingying was born in 1986. He visited and studied in University of Pisa in 2014, and received his Ph.D. degree in aeronautical and astronautical science and technology from Harbin Institute of Technology in 2015. He is currently a research assistant in Harbin Institute of Technology. His research interests are dynamics and control of electric sail, deep-space exploration, path planning of spacecraft, spacecraft simulator technique and system, and simulation of low gravity environment. E-mail: huomingying123@163.com|QI Naiming is a professor with School of Astronautics, Harbin Institute of Technology. He received his Ph.D. degree from Harbin Institute of Technology in 2001. His area of research includes aircraft dynamics, guidance, simulation of space environment, and control and integration of electro-mechanical system. E-mail: qinmok@163.com
  • Supported by:
    the National Natural Science Foundation of China(11672093);the National Natural Science Foundation of China(51705109);the Special Foundation of Heilongjiang Postdoctoral Science(LBH-TZ1609);the Open Fund of National Defense Key Discipline Laboratory of Micro-Spacecraft Technology(HIT.KLOF.MST.201507);the Fundamental Research Funds for the Central Universities(HIT.NSRIF.201622);This work was supported by the National Natural Science Foundation of China (11672093; 51705109), the Special Foundation of Heilongjiang Postdoctoral Science (LBH-TZ1609), the Open Fund of National Defense Key Discipline Laboratory of Micro-Spacecraft Technology (HIT.KLOF.MST.201507), and the Fundamental Research Funds for the Central Universities (HIT.NSRIF.201622)

Abstract:

The disturbance torque of aerostatic bearings is in the same order of the reaction wheel, which causes difficulty in evaluation of the designed attitude control strategy of a nano-satellite based on the aerostatic bearing. Two approaches are proposed to model the disturbance torque. Firstly, the gravity induced moment, the vortex torque, and the damping moment are modeled separately. However, the vortex torque and the damping moment are coupled with each other as both of them are caused by the viscosity. In the second approach, the coupling effect is considered. A nano-satellite is constructed based on aerostatic bearing. The time history of the free rotation rate from an initial speed is measured by the gyro, which is further used to calculate the rotation angle and acceleration. The static vortex torque is measured via the removable micro-torque measurement system. Based on these data, the model parameters are identified and modeling errors are presented. Results show that the second model is more precise. The root mean squire error is less than 0.5×10-4 N·m and the relative error of the static vortex torque is 0.16%.

Key words: aerostatic bearing, disturbance torque, vortex torque, spacecraft simulator, modeling and identification