Abstract: Besides performing the function of tracking and detection of targets, novel targeting pods have strapdown inertial navigation systems equipped in them to perform the navigation function. The strapdown navigation system fitted in a targeting pod usually adopts low precision inertial components, and the transfer alignment process is performed only in low dynamic conditions. To solve the above problem, a novel transfer alignment method is proposed to estimate and modify the misalignment and other states in real time. The method utilizes the specific force difference integration and angular velocity of the main inertial navigation system and the slave inertial navigation system to implement transfer alignment. The observability of the system states is analyzed in conditions of low instrument precision and low dynamics. A simulation project is designed and the result shows that the misalignment of the method can meet the performance requirements of rapid transfer alignment and that the performance reaches 5′, which is better than the traditional alignment method in conditions of low instrument precision and low dynamics.

Key words: targeting pod, strapdown inertial navigation system, transfer alignment, Kalman filters, bending distortion