皮卫星星箭分离动力学模拟及其灵敏度分析

皮卫星能源有限、姿控能力差等特点决定其对星箭分离初始姿态要求较高。在采用自主研发的皮卫星星箭分离机构的基础上，以多体动力学理论为基础，采用ADAMS软件建立了皮卫星及其星箭分离机构虚拟样机模型，分别就皮卫星质心偏离量、分离弹簧与舱门扭簧弹性系数对入轨初始姿态影响展开了分析。分析结果表明：质心偏心量对分离姿态影响最明显，分离弹簧与舱门扭簧弹性系数对其影响次之，合理配置分离弹簧与舱门扭簧弹性系数有利于卫星保持良好的姿态分离。在轨分离试验显示：分离时刻皮卫星滚动角速度、俯仰角速度、偏航角速度分别为-0.18（°）/s，-1.6（°）/s，0.95（°）/s，与在轨环境下仿真结果基本相符；入轨初始姿态能满足皮卫星的姿控要求，为其后续工作提供了保障。

Dynamic Simulation and Sensitivity Analysis of Picosatellite Separation System

The picosatellite attitude control system makes high claims on orbit injection initial attitude for its limited energy and poor attitude control ability. In this article, based on the self-developed separation mechanism of picosatellite and the multi-body dynamics theory, the virtual prototype model of picosatellite and its separation mechanism is established by ADAMS software. The influences of the picosatellite eccentricity, the main spring elastic coefficient and the elastic coefficient of the torsional spring on the initial attitude are analyzed. The result shows that the eccentricity of the picosatellite has the most obvious influence on the separation attitude, followed by the elastic coefficient of the main spring and the torsional spring. The reasonable configuration of the elastic coefficient of the main spring and elastic coefficient of the torsional spring are conducive to maintain a good separation attitude. Moreover, the on-orbit separation test shows that the rolling rate, pitch rate and yaw rate are -0.18（°）/s,-1.60（°）/s and 0.95（°）/s respectively, which are consistent with the simulation results under the in-orbit environment. The initial attitude in orbit can satisfy the requirement of the attitude control system of picosatellite and provide guarantee for its follow-up activities.