tailieunhanh - Sensor Fusion and its Applications Part 2

Tham khảo tài liệu 'sensor fusion and its applications part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 24 Sensor Fusion and Its Applications P 1 k 1 . PNk 1 PJk 1 PNỈ k 1 . PNN k ĩ PN m k ĩ PẠk 1 PmN k 1 PJk 1 B k 1 0 0 i 0 0 BT k 1 0 01 . 0 BN k 1 0 0 PN N k 0 0 . BN k 1 0 0 0 k 0 0 P k mm 0 . 0 r k J C k 1 . 0 0 PQk 0 0 Ck 1 .0 0 1 0 Q k 1 0 0 PQ 0 0 CN k 1 0 0 0 r k _ 0 0 Qk _ 0 .0 rT k _ If taken the equal sign that is achieved the de-correlation of local estimates on the one hand the global optimal fusion estimate can be realized by Theorem but on the other the initial covariance matrix and process noise covariance of the sub-filter themselves can enlarged by Pi 1 times. What s more the filter results of every local filter will not be optimal. Structure and Performance Analysis of the Combined Filter The combined filter is a 2-level filter. The characteristic to distinguish from the traditional distributed filters is the use of information distribution to realize information share of every sub-filter. Information fusion structure of the combined filter is shown in Fig. . Fig. Structure Indication of the Combined Filter State Optimal Estimation for Nonstandard Multi-sensor Information Fusion System 25 From the filter structure shown in the Fig. the fusion process for the combined filter can be divided into the following four steps. Stepl Given initial value and information distribution The initial value of the global state in the initial moment is supposed to be X0 the covariance to be Qo the state estimate vector of the local filter the system covariance matrix and the state vector covariance matrix separately respectively to be Xị Qi Pị i 1 N and the corresponding master filter to be X . Q P .The information is distributed through the information distribution m m m factor by the following rules in the sub-filter and the master filter. ÍQ-1 k Q-1 k Q-1 k - Q-1 k Q1 k Q k pQQXk g X i X SÍ-2 X NX m X ii-i X s r i g X pa. k PT1 k k p- k k - p- k k p k k pa. k Rp k k g X I 1x1 2x1 N X I m X I i X I gxl X k k Xg k k i 1 2 - N m Where Pị