A Method for Controlling Angular Momentum of Spacecraft in Inertial System

Abstract

The invention discloses angular momentum control method of a spacecraft in an inertial system. The method is characterized in that a three-axis stabile control is performed in the inertial system, and the feedback design is performed based on the angular momentum and three-axis posture angle information of a performing mechanism to obtain a feedback controller. According to the method, that the gravity gradient torque is to be more than the pneumatic torque is removed; the performing mechanism is unsaturated while the long-term stable flying is ensured; the method is applied to the spacecraft posture control in the circumstance that a magnetorquer cannot be assembled or the magnetorquer suffers from fault and unloading cannot be or is not proposed to be performed by the air injection mode.

Description

technical field [0001] The invention relates to an angular momentum control method, which belongs to the field of spacecraft attitude control. Background technique [0002] When a spacecraft using angular momentum exchange actuators (flywheels, control torque gyroscopes) for attitude control is in orbit for a long time, under the action of space environment disturbance torque, the angular momentum of the actuators will increase and then reach saturation. Momentum unloaded. At present, the main unloading methods include magnetic torque device unloading and jet unloading. [0003] Due to the large inertia of the space station, the environmental torque is also large. For example, the maximum aerodynamic moment of the International Space Station reaches 8.8Nm. It is impossible to use the magnetic torquer to complete the unloading of the angular kinetic accumulation caused by such a large external disturbance torque. Therefore, the space station uses The gravitational gradient ...

AI Technical Summary

Problems solved by technology

The International Space Station actually uses the gravity gradient moment to balance the aerodynamic moment, so the inertia characteristics of the space station must meet certain constraints, that is, its main inertial axes must have a large difference in order to generate enough gravity gradient moment to balance the aerodynamic moment, but this requirement Sometimes it cannot be satisfied. For example, when my country’s space station had only one core module in orbit in the early days, due to the slender configuration of the module, the moment of inertia of the pitch axis and the yaw axis were close, so it could not generate enough gravity gradient moment. Angular momentum control not possible with moment balance attitude control

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