calculate SN3D A2B matrix instead of FUMA

A2B_matrix.m

@@ -15,7 +15,7 @@ function [A2B pv max_err] = A2B_matrix(Y, X, v_z_factor)
   pv = X1 \ Y;
   max_err = max (Y - (X1 * pv));
   pv = fill_v_z( pv );
-  A2B = [sqrt(2)/2 0 0 0; 0 1 0 0; 0 0 1 0; 0 0 0 1] / pv;
+  A2B = [1 0 0 0; 0 1 0 0; 0 0 1 0; 0 0 0 1] / pv;
 end
 
 function X = measurement_dirs_z0(n)