Место издания:State Research Center of the Russian Federation Concern CSRI Elektropribor, JSC
Первая страница:76
Последняя страница:80
Аннотация:The aim of the study is to modify previously developed inertial measurement unit calibration method in order to take sensor error variations over temperature time derivative into consideration. The method itself is designed for calibration of inertial measurement units of navigation, tactical and low grade on a turntable with horizontal axis of rotation. Conventional parameters of inertial sensor error model – null biases, errors of scaling factors, sensor misalignments, dynamic drift coefficients and others, if necessary, – are estimated. Since the motion of an inertial unit in calibration is not arbitrary (only rotation and no linear translation), sensor output becomes redundant, and not only the motion itself can be determined, but also sensor error parameters, under appropriate conditions of observability. Neither angular nor rate measurement or precise positioning is required from the turntable. This allows us to get estimates for all desired parameters in a simple procedure with no need in precise equipment and without strict compliance with any predefined plan of operations. Introducing linear sensor error variations over temperature time derivative into the model, we demonstrate that its coefficients are observable in an experiment similar to that in previously developed calibration method, but with temperature changing over time. Using covariance analysis we get an estimation of calibration accuracy in experiments with two different temperature modes – inertial unit self-heating and controlled linear temperature change in a thermal chamber.
