Control algorithm design of platform rotation for hybrid inertial navigation system
Hybrid inertial navigation system(HINS)can effectively improve the independent navigation accuracy of inertial navigation system by using error modulation.The traditional three-frame HINS platform rotation control algorithm can stabilize the rotational platform relative to the reference frame(geographical system or inertial system).However,singularity will appear when error modulation rotation is superimposed on this basis,which makes the rotational platform unable to rotate in a predetermined way.To solve the problem of singularity,the transforming relation between the corresponding coordinate systems during the rotation of HINS rotational platform under different navigation states is analyzed.Taking the control of the rotational platform to reach the specified position as the control goal,the quaternion is used to solve the control instructions,and a quaternion rotational platform control algorithm is designed based on the coordinate transforming relationship.The results of simulation and experiment show that the proposed algorithm avoids singularity when calculating the angular position information of frame instructions,and makes the three-frame HINS rotate in a predetermined way.