Patent ID: 11912433
Assignee: SOUTHEAST UNIVERSITY
Field: Transport (Mechanical engineering)
Classification: CPC B  G | IPC B  G

Claim 2:
3. The dual-filter-based transfer alignment method under dynamic deformation according to claim 2, wherein in step (2), the flexural deformation angle, the flexural deformation angular speed and the coupling angle are used as state quantities and the model of filter 1 is established with an attitude matching method as follows:
the state quantities of the filter 1 are selected as follows:

x1=[δ{right arrow over (ϕ)} {right arrow over (ε)}s {right arrow over (ρ)}0 {right arrow over (θ)} {right arrow over ({dot over (θ)})} Δ{right arrow over (ϕ)}]T,

wherein, δ{right arrow over (ϕ)} represents attitude error, {right arrow over (ε)}s represents zero drift of gyro measurement in the subsystem, and {right arrow over (ρ)}0 represents initial installation angle error between the main system and the subsystem;
the state equation of filter 1 is:

{dot over (x)}1=F1x1+G1w1,

wherein, F1 represents the state transition matrix of filter 1, G1 represents the system noise distribution matrix of filter 1, w1 represents the system noise of filter 1, the state transition matrix F1 is expressed as:, F
    1
   
   =
   
    [
    
     
      
       
        (
        
         
          -
          
           
            ω
            →
           
           in
           m
          
         
         ×
        
        )
       
      
      
       
        -
        
         C
         
          s
          ′
         
         n
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
     
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
     
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
     
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        I
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
     
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        B
        1
       
      
      
       
        B
        2
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
     
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
      
       
        F
        64
       
      
      
       
        F
        65
       
      
      
       
        0
        
         3
         ×
         3
        
       
      
     
    
    ]
   
  
  ,
 

wherein, {right arrow over (ω)}inn represents the rotation of the navigation system with respect to the inertial system, {right arrow over (ω)}inn× represents an antisymmetric matrix, Csn, represents a transformation matrix between the ideal coordinate system of the subsystem and the navigation coordinate system, and, B
    1
   
   =
   
    [
    
     
      
       0
      
      
       
        
         -
         2
        
        ⁢
        
         β
         y
        
       
      
      
       0
      
     
     
      
       0
      
      
       0
      
      
       
        
         -
         2
        
        ⁢
        
         β
         z
        
       
      
     
     
      
       
        
         -
         2
        
        ⁢
        
         β
         x
        
       
      
      
       0
      
      
       0
      
     
    
    ]
   
  
  ⁢
  

  
   
    
     B
     2
    
    =
    
     [
     
      
       
        0
       
       
        
         -
         
          β
          y
          2
         
        
       
       
        0
       
      
      
       
        0
       
       
        0
       
       
        
         -
         
          β
          z
          2
         
        
       
      
      
       
        
         -
         
          β
          x
          2
         
        
       
       
        0
       
       
        0
       
      
     
     ]
    
   
   ,, βi(i=x,y,x) represent the coefficients of the second-order Markov model in east, north, and sky directions, F64=MB2, F65=MB1;
the system measurement equation is:

y1=H1x1+μ1,

wherein, y1 represents the difference between the true value of attitude and the estimated value from the filter, H1 represents the measurement matrix of the filter 1, and μ1 represents the measurement noise in the filter 1.