姿态敏感器地面标定精密调整机构设计

Design of accurate adjustment mechanism for the attitude sensor

为了满足光学姿态敏感器地面标定更高精度的应用需求,针对当前敏感器地面测试设备的标定精度与设计值不一致的实际问题,提出了一种分辨率高、稳定性好的五自由度精密调整机构设计方案。分析了光轴一致性误差对星点位置误差的影响,结合姿态敏感器技术指标,采用搭积的调整层结构形式及合理的消隙方法,设计符合敏感器标定要求的调整架机械结构并进行力学分析。仿真结果与测试数据表明:调整机构的实测位移分辨率优于0.1μm,角分辨达到0.1″,在对星图的反复测试中,降低了光轴一致性误差对测试结果的影响,星点位置误差比使用常规调整机构时提高了5″以上,达到了敏感器地面标定的精度要求。

Aiming at the current practical problem that the calibration precision of ground test equipment of sensors is inconsistent with the design value, a design scheme for a precision adjusting mechanism is presented with high resolution, high stability and five degree of freedom, in order to meet the higher precision application demand of ground calibration of optical attitude sensors. At first, the influence of conformity error of optical axis on position error of star point is analyzed. With a combination of the technical indicators of attitude sensors, we adopt the independent control method of stacked adjusting hierarchy. Then, the gap elimination method is determined according to the gap form within the mechanism. Besides, an adjusting mechanism structure meeting the calibration requirements for sensors is designed. After that, statics analysis and modal analysis are carried out. Simulation results and test data show that the actual measurement displacement resolution of the adjusting mechanism is better than 0.1 p,m, and the angular resolution is 0.1 second of arc. During the stability test of star point position, star point position error decreases more than 5＂ compared with the error value in the test which adopts conventional adjusting mechanisms. It may reduce the influence of conformity error of the optical axis on the calibration precision of sensors and improve reliability of calibration results.