锥运动条件下新的速度误差补偿项研究

A Novel Error Compensation Term in Velocity Updating of SINS under Coning Angular Motion Conditions

经典的捷联惯导积分算法往往需要在姿态更新过程中对圆锥误差项进行精确补偿。虽然考虑了载体姿态变化的影响,但速度更新算法通常忽略了圆锥效应的作用。就圆锥误差项引起的速度误差进行了研究。指出其与陀螺角增量对速度更新的影响方式相同。在假设的线性斜坡模型条件下,利用两个连续的角增量和比力增量,详细推导了新的速度误差项的二子样更新补偿算法。在一种特殊的机动条件下,即当载体绕横轴作圆锥角振动的同时又沿立轴作同频同相的线振动,推导的二子样优化算法能够使该误差补偿项的平均性能最优。仿真结果证明该优化算法能够对新的速度误差积分项进行有效的补偿。

Coning effects must be accurately compensated in the attitude updating of the classical strapdown inertial navigation integration algorithm. These effects are not involved in the velocity updating, though the attitude change is being taken into it. The novel velocity error term induced by the coning correction is studied in this paper. These effects as the gyro angular increment data have the influence on the velocity updating in the same way. For the assumed linear ramp model, a two-sample compensation algorithm for the novel velocity error term is deduced in detail by using the two successive integrated angular rate increment and specific force increment measurements. The weighting coefficients are then optimized for best average performance in a specific environment, i.e. the body is exposed to a coning angular vibration about the x axis of the body frame combined with a linear vibration at the same frequency and in phase along the z axis. The simulation results validate that the two-sample optimization algorithm can compensate the integrated term of the novel velocity error effectively.