【注】本文所述的函数kfinit0不同于kfinit，后者的讲解链接见：PSINS工具箱函数介绍——kfinit

kfinit是kf的参数初始化函数，用于初始化滤波参数
本文所述的代码需要基于PSINS工具箱，工具箱的讲解：

• PSINS初学指导：https://blog.csdn.net/callmeup/article/details/137087932

kfinit0被kfinit调用，用于初始化kfinit函数里面没有定义的字段

使用方法

kf = kfinit0(kf, nts);
kf是关于卡尔曼滤波的参数，是一个结构体，参考kfinit这个函数：https://blog.csdn.net/callmeup/article/details/140779776
另一个输入值nts是INS的采样周期，一般在kfinit这个函数里面从ins结构体里面提取：

例程

代码

function kf = kfinit0(kf, nts)
% Always called by kfinit and initialize the remaining fields of kf.
%
% See also kfinit, kfupdate, kffeedback, psinstypedef.kf.nts = nts;[kf.m, kf.n] = size(kf.Hk);kf.I = eye(kf.n);kf.Kk = zeros(kf.n, kf.m);kf.measmask = [];            % measurement mask for no update  20/11/2022kf.measstop = zeros(kf.m,1); % measurement stop timekf.measlost = zeros(kf.m,1); % measurement lost timekf.measlog = 0;              % measurement log flagif ~isfield(kf, 'xk'),  kf.xk = zeros(kf.n, 1);  endif ~isfield(kf, 'Qk'),  kf.Qk = kf.Qt*kf.nts;  endif ~isfield(kf, 'Gammak'),  kf.Gammak = 1; kf.l = kf.n;  else, kf.l=size(kf.Gammak,2);  endif ~isfield(kf, 'fading'),  kf.fading = 1;  endif ~isfield(kf, 'adaptive'),  kf.adaptive = 0;  end
%     if kf.adaptive==1if ~isfield(kf, 'b'),  kf.b = 0.5;  endif ~isfield(kf, 'beta'),  kf.beta = 1;  endif ~isfield(kf, 'Rmin'),  kf.Rmin = 0.01*kf.Rk;  endif ~isfield(kf, 'Rmax'),  kf.Rmax = 100*kf.Rk;  endif ~isfield(kf, 'Qmin'),  kf.Qmin = 0.01*kf.Qk;  endif ~isfield(kf, 'Qmax'),  kf.Qmax = 100*kf.Qk;  end
%     endif ~isfield(kf, 'xtau'),  kf.xtau = ones(size(kf.xk))*eps;   endif ~isfield(kf, 'T_fb'),  kf.T_fb = 1;   endif ~isfield(kf, 'fbstr'),  kf.fbstr = 'avped';  endif ~isfield(kf, 'xconstrain'),  kf.xconstrain = 0;  endif ~isfield(kf, 'pconstrain'),  kf.pconstrain = 0;  endkf.Pmax = (diag(kf.Pxk)+1)*1.0e10;kf.Pmin = kf.Pmax*0;
%     kf.Pykk_1 = kf.Hk*kf.Pxk*kf.Hk'+kf.Rk;kf.Pykk_1 = kf.Hk*kf.Pxk*kf.Hk'+0;kf.xfb = zeros(kf.n, 1);
%     kf.coef_fb = (1.0-exp(-kf.T_fb./kf.xtau));
%     kf.coef_fb = ar1coefs(kf.T_fb, kf.xtau);xtau = kf.xtau;xtau(kf.xtau<kf.T_fb) = kf.T_fb;  kf.coef_fb = kf.T_fb./xtau;  %2015-2-22

运行结果

略

代码解析

kfinit0生成的量一般无关紧要，这里挑几个讲：

• kf.Kk：初始化Kf
  

• kf.Pykk_1：对$P_y$的计算