  Bioinspired polarized skylight navigation system (PSNS) is a new navigation
method, which imitates insects using polarized skylight for navigation.
However, the latest research shows that the current PSNS is difficult to obtain
the three-dimensional (3D) attitude in real time only relying on polarized
skylight. This causes not only that three-dimensional (3D) cannot be estimated
only by PSNS in real time, but also when polarized light is integrated with
other navigation methods, 3D attitude cannot be directly used for integrated
navigation. Therefore, an integrated navigation algorithm based on bi-direction
solar vector is proposed, and a DSP+FPGA (digital signal processor + field
programmable gate array) dual-core architecture PSNS/GNSS/SINS (global
navigation satellite system/strapdown inertial navigation system) integrated
navigation system was constructed.
