Self-Calibration for Size Effect With Constrained Virtual Points

The principle of compensating size effect by special structure design or structure design value has its limitation. In this article, the internal size effect and the rotation center size effect are considered, and the coupling between them is eliminated by the constraint of virtual point position. Moreover, in order to avoid the influence of other error sources on the size effect error calibration, such as the gyro-accelerometer asynchronous time and quadratic error of the accelerometer are considered in the state equation to develop a 46D Kalman filter self-calibration model. The calibration accuracy of the size effect is better than 1.2 mm by comparing the design values of the high precision inertial measurement unit physical structure dimensions. The navigation experiment shows that the accuracy of velocity can be increased by more than 4.4 times after the size effect error is compensated.