diff --git a/matlab/generated/Inertial Nav EKF/Optical Flow Fusion Alternative.txt b/matlab/generated/Inertial Nav EKF/Optical Flow Fusion Alternative.txt
new file mode 100644
index 0000000000..fbe105bf32
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+++ b/matlab/generated/Inertial Nav EKF/Optical Flow Fusion Alternative.txt	
@@ -0,0 +1,281 @@
+// Auto code for fusion of line of sight rate massurements from a optical flow camera aligned with the Z body axis
+// Generated using MAtlab in-built symbolic toolbox to c-code function
+// Observations are body modtion compensated optica flow rates about the X and Y body axis
+// Sequential fusion is used (observation errors about each axis are assumed to be uncorrelated)
+
+// intermediate variable from algebraic optimisation
+float SH_LOS[14];
+SH_LOS[0] = sq(q0) - sq(q1) - sq(q2) + sq(q3);
+SH_LOS[1] = vn*(sq(q0) + sq(q1) - sq(q2) - sq(q3)) - vd*(2*q0*q2 - 2*q1*q3) + ve*(2*q0*q3 + 2*q1*q2);
+SH_LOS[2] = ve*(sq(q0) - sq(q1) + sq(q2) - sq(q3)) + vd*(2*q0*q1 + 2*q2*q3) - vn*(2*q0*q3 - 2*q1*q2);
+SH_LOS[3] = 1/(pd - ptd);
+SH_LOS[4] = vd*SH_LOS[0] - ve*(2*q0*q1 - 2*q2*q3) + vn*(2*q0*q2 + 2*q1*q3);
+SH_LOS[5] = 2.0f*q0*q2 - 2.0f*q1*q3;
+SH_LOS[6] = 2.0f*q0*q1 + 2.0f*q2*q3;
+SH_LOS[7] = q0*q0;
+SH_LOS[8] = q1*q1;
+SH_LOS[9] = q2*q2;
+SH_LOS[10] = q3*q3;
+SH_LOS[11] = q0*q3*2.0f;
+SH_LOS[12] = pd-ptd;
+SH_LOS[13] = 1.0f/(SH_LOS[12]*SH_LOS[12]);
+
+// Calculate the observation jacobians for the LOS rate about the X body axis
+float H_LOS[24];
+H_LOS[0] = SH_LOS[3]*SH_LOS[2]*SH_LOS[6]-SH_LOS[3]*SH_LOS[0]*SH_LOS[4];
+H_LOS[1] = SH_LOS[3]*SH_LOS[2]*SH_LOS[5];
+H_LOS[2] = SH_LOS[3]*SH_LOS[0]*SH_LOS[1];
+H_LOS[3] = SH_LOS[3]*SH_LOS[0]*(SH_LOS[11]-q1*q2*2.0f);
+H_LOS[4] = -SH_LOS[3]*SH_LOS[0]*(SH_LOS[7]-SH_LOS[8]+SH_LOS[9]-SH_LOS[10]);
+H_LOS[5] = -SH_LOS[3]*SH_LOS[0]*SH_LOS[6];
+H_LOS[8] = SH_LOS[2]*SH_LOS[0]*SH_LOS[13];
+
+// Calculate the observation jacobians for the LOS rate about the Y body axis
+float H_LOS[24];
+H_LOS[0] = -SH_LOS[3]*SH_LOS[6]*SH_LOS[1];
+H_LOS[1] = -SH_LOS[3]*SH_LOS[0]*SH_LOS[4]-SH_LOS[3]*SH_LOS[1]*SH_LOS[5];
+H_LOS[2] = SH_LOS[3]*SH_LOS[2]*SH_LOS[0];
+H_LOS[3] = SH_LOS[3]*SH_LOS[0]*(SH_LOS[7]+SH_LOS[8]-SH_LOS[9]-SH_LOS[10]);
+H_LOS[4] = SH_LOS[3]*SH_LOS[0]*(SH_LOS[11]+q1*q2*2.0f);
+H_LOS[5] = -SH_LOS[3]*SH_LOS[0]*SH_LOS[5];
+H_LOS[8] = -SH_LOS[0]*SH_LOS[1]*SH_LOS[13];
+
+// Intermediate variables used to calculate the Kalman gain matrices for the LOS rate about the X body axis
+float t2 = SH_LOS[3];
+float t3 = SH_LOS[0];
+float t4 = SH_LOS[2];
+float t5 = SH_LOS[6];
+float t100 = t2 * t3 * t5;
+float t6 = SH_LOS[4];
+float t7 = t2*t3*t6;
+float t9 = t2*t4*t5;
+float t8 = t7-t9;
+float t10 = q0*q3*2.0f;
+float t21 = q1*q2*2.0f;
+float t11 = t10-t21;
+float t101 = t2 * t3 * t11;
+float t12 = pd-ptd;
+float t13 = 1.0f/(t12*t12);
+float t104 = t3 * t4 * t13;
+float t14 = SH_LOS[5];
+float t102 = t2 * t4 * t14;
+float t15 = SH_LOS[1];
+float t103 = t2 * t3 * t15;
+float t16 = q0*q0;
+float t17 = q1*q1;
+float t18 = q2*q2;
+float t19 = q3*q3;
+float t20 = t16-t17+t18-t19;
+float t105 = t2 * t3 * t20;
+float t22 = P[1][1]*t102;
+float t23 = P[3][0]*t101;
+float t24 = P[8][0]*t104;
+float t25 = P[1][0]*t102;
+float t26 = P[2][0]*t103;
+float t63 = P[0][0]*t8;
+float t64 = P[5][0]*t100;
+float t65 = P[4][0]*t105;
+float t27 = t23+t24+t25+t26-t63-t64-t65;
+float t28 = P[3][3]*t101;
+float t29 = P[8][3]*t104;
+float t30 = P[1][3]*t102;
+float t31 = P[2][3]*t103;
+float t67 = P[0][3]*t8;
+float t68 = P[5][3]*t100;
+float t69 = P[4][3]*t105;
+float t32 = t28+t29+t30+t31-t67-t68-t69;
+float t33 = t101*t32;
+float t34 = P[3][8]*t101;
+float t35 = P[8][8]*t104;
+float t36 = P[1][8]*t102;
+float t37 = P[2][8]*t103;
+float t70 = P[0][8]*t8;
+float t71 = P[5][8]*t100;
+float t72 = P[4][8]*t105;
+float t38 = t34+t35+t36+t37-t70-t71-t72;
+float t39 = t104*t38;
+float t40 = P[3][1]*t101;
+float t41 = P[8][1]*t104;
+float t42 = P[2][1]*t103;
+float t73 = P[0][1]*t8;
+float t74 = P[5][1]*t100;
+float t75 = P[4][1]*t105;
+float t43 = t22+t40+t41+t42-t73-t74-t75;
+float t44 = t102*t43;
+float t45 = P[3][2]*t101;
+float t46 = P[8][2]*t104;
+float t47 = P[1][2]*t102;
+float t48 = P[2][2]*t103;
+float t76 = P[0][2]*t8;
+float t77 = P[5][2]*t100;
+float t78 = P[4][2]*t105;
+float t49 = t45+t46+t47+t48-t76-t77-t78;
+float t50 = t103*t49;
+float t51 = P[3][5]*t101;
+float t52 = P[8][5]*t104;
+float t53 = P[1][5]*t102;
+float t54 = P[2][5]*t103;
+float t79 = P[0][5]*t8;
+float t80 = P[5][5]*t100;
+float t81 = P[4][5]*t105;
+float t55 = t51+t52+t53+t54-t79-t80-t81;
+float t56 = P[3][4]*t101;
+float t57 = P[8][4]*t104;
+float t58 = P[1][4]*t102;
+float t59 = P[2][4]*t103;
+float t83 = P[0][4]*t8;
+float t84 = P[5][4]*t100;
+float t85 = P[4][4]*t105;
+float t60 = t56+t57+t58+t59-t83-t84-t85;
+float t66 = t8*t27;
+float t82 = t100*t55;
+float t86 = t105*t60;
+float t61 = R_LOS+t33+t39+t44+t50-t66-t82-t86; // innovation variance - should always be >= R_LOS
+float t62 = 1.0f/t61;
+
+// Calculate the Kalman gain matrix for the LOS rate about the X body axis
+float Kfusion[24];
+Kfusion[0] = t62*(-P[0][0]*t8-P[0][5]*t100+P[0][3]*t101+P[0][1]*t102+P[0][2]*t103+P[0][8]*t104-P[0][4]*t105);
+Kfusion[1] = t62*(t22-P[1][0]*t8-P[1][5]*t100+P[1][3]*t101+P[1][2]*t103+P[1][8]*t104-P[1][4]*t105);
+Kfusion[2] = t62*(t48-P[2][0]*t8-P[2][5]*t100+P[2][3]*t101+P[2][1]*t102+P[2][8]*t104-P[2][4]*t105);
+Kfusion[3] = t62*(t28-P[3][0]*t8-P[3][5]*t100+P[3][1]*t102+P[3][2]*t103+P[3][8]*t104-P[3][4]*t105);
+Kfusion[4] = t62*(-t85-P[4][0]*t8-P[4][5]*t100+P[4][3]*t101+P[4][1]*t102+P[4][2]*t103+P[4][8]*t104);
+Kfusion[5] = t62*(-t80-P[5][0]*t8+P[5][3]*t101+P[5][1]*t102+P[5][2]*t103+P[5][8]*t104-P[5][4]*t105);
+Kfusion[6] = t62*(-P[6][0]*t8-P[6][5]*t100+P[6][3]*t101+P[6][1]*t102+P[6][2]*t103+P[6][8]*t104-P[6][4]*t105);
+Kfusion[7] = t62*(-P[7][0]*t8-P[7][5]*t100+P[7][3]*t101+P[7][1]*t102+P[7][2]*t103+P[7][8]*t104-P[7][4]*t105);
+Kfusion[8] = t62*(t35-P[8][0]*t8-P[8][5]*t100+P[8][3]*t101+P[8][1]*t102+P[8][2]*t103-P[8][4]*t105);
+Kfusion[9] = t62*(-P[9][0]*t8-P[9][5]*t100+P[9][3]*t101+P[9][1]*t102+P[9][2]*t103+P[9][8]*t104-P[9][4]*t105);
+Kfusion[10] = t62*(-P[10][0]*t8-P[10][5]*t100+P[10][3]*t101+P[10][1]*t102+P[10][2]*t103+P[10][8]*t104-P[10][4]*t105);
+Kfusion[11] = t62*(-P[11][0]*t8-P[11][5]*t100+P[11][3]*t101+P[11][1]*t102+P[11][2]*t103+P[11][8]*t104-P[11][4]*t105);
+Kfusion[12] = t62*(-P[12][0]*t8-P[12][5]*t100+P[12][3]*t101+P[12][1]*t102+P[12][2]*t103+P[12][8]*t104-P[12][4]*t105);
+Kfusion[13] = t62*(-P[13][0]*t8-P[13][5]*t100+P[13][3]*t101+P[13][1]*t102+P[13][2]*t103+P[13][8]*t104-P[13][4]*t105);
+Kfusion[14] = t62*(-P[14][0]*t8-P[14][5]*t100+P[14][3]*t101+P[14][1]*t102+P[14][2]*t103+P[14][8]*t104-P[14][4]*t105);
+Kfusion[15] = t62*(-P[15][0]*t8-P[15][5]*t100+P[15][3]*t101+P[15][1]*t102+P[15][2]*t103+P[15][8]*t104-P[15][4]*t105);
+Kfusion[16] = t62*(-P[16][0]*t8-P[16][5]*t100+P[16][3]*t101+P[16][1]*t102+P[16][2]*t103+P[16][8]*t104-P[16][4]*t105);
+Kfusion[17] = t62*(-P[17][0]*t8-P[17][5]*t100+P[17][3]*t101+P[17][1]*t102+P[17][2]*t103+P[17][8]*t104-P[17][4]*t105);
+Kfusion[18] = t62*(-P[18][0]*t8-P[18][5]*t100+P[18][3]*t101+P[18][1]*t102+P[18][2]*t103+P[18][8]*t104-P[18][4]*t105);
+Kfusion[19] = t62*(-P[19][0]*t8-P[19][5]*t100+P[19][3]*t101+P[19][1]*t102+P[19][2]*t103+P[19][8]*t104-P[19][4]*t105);
+Kfusion[20] = t62*(-P[20][0]*t8-P[20][5]*t100+P[20][3]*t101+P[20][1]*t102+P[20][2]*t103+P[20][8]*t104-P[20][4]*t105);
+Kfusion[21] = t62*(-P[21][0]*t8-P[21][5]*t100+P[21][3]*t101+P[21][1]*t102+P[21][2]*t103+P[21][8]*t104-P[21][4]*t105);
+Kfusion[22] = t62*(-P[22][0]*t8-P[22][5]*t100+P[22][3]*t101+P[22][1]*t102+P[22][2]*t103+P[22][8]*t104-P[22][4]*t105);
+Kfusion[23] = t62*(-P[23][0]*t8-P[23][5]*t100+P[23][3]*t101+P[23][1]*t102+P[23][2]*t103+P[23][8]*t104-P[23][4]*t105);
+
+// Intermediate variables used to calculate the Kalman gain matrices for the LOS rate about the Y body axis
+float t2 = SH_LOS[3];
+float t3 = SH_LOS[0];
+float t4 = SH_LOS[1];
+float t5 = SH_LOS[5];
+float t100 = t2 * t3 * t5;
+float t6 = SH_LOS[4];
+float t7 = t2*t3*t6;
+float t8 = t2*t4*t5;
+float t9 = t7+t8;
+float t10 = q0*q3*2.0f;
+float t11 = q1*q2*2.0f;
+float t12 = t10+t11;
+float t101 = t2 * t3 * t12;
+float t13 = pd-ptd;
+float t14 = 1.0f/(t13*t13);
+float t104 = t3 * t4 * t14;
+float t15 = SH_LOS[6];
+float t105 = t2 * t4 * t15;
+float t16 = SH_LOS[2];
+float t102 = t2 * t3 * t16;
+float t17 = q0*q0;
+float t18 = q1*q1;
+float t19 = q2*q2;
+float t20 = q3*q3;
+float t21 = t17+t18-t19-t20;
+float t103 = t2 * t3 * t21;
+float t22 = P[0][0]*t105;
+float t23 = P[1][1]*t9;
+float t24 = P[8][1]*t104;
+float t25 = P[0][1]*t105;
+float t26 = P[5][1]*t100;
+float t64 = P[4][1]*t101;
+float t65 = P[2][1]*t102;
+float t66 = P[3][1]*t103;
+float t27 = t23+t24+t25+t26-t64-t65-t66;
+float t28 = t9*t27;
+float t29 = P[1][4]*t9;
+float t30 = P[8][4]*t104;
+float t31 = P[0][4]*t105;
+float t32 = P[5][4]*t100;
+float t67 = P[4][4]*t101;
+float t68 = P[2][4]*t102;
+float t69 = P[3][4]*t103;
+float t33 = t29+t30+t31+t32-t67-t68-t69;
+float t34 = P[1][8]*t9;
+float t35 = P[8][8]*t104;
+float t36 = P[0][8]*t105;
+float t37 = P[5][8]*t100;
+float t71 = P[4][8]*t101;
+float t72 = P[2][8]*t102;
+float t73 = P[3][8]*t103;
+float t38 = t34+t35+t36+t37-t71-t72-t73;
+float t39 = t104*t38;
+float t40 = P[1][0]*t9;
+float t41 = P[8][0]*t104;
+float t42 = P[5][0]*t100;
+float t74 = P[4][0]*t101;
+float t75 = P[2][0]*t102;
+float t76 = P[3][0]*t103;
+float t43 = t22+t40+t41+t42-t74-t75-t76;
+float t44 = t105*t43;
+float t45 = P[1][2]*t9;
+float t46 = P[8][2]*t104;
+float t47 = P[0][2]*t105;
+float t48 = P[5][2]*t100;
+float t63 = P[2][2]*t102;
+float t77 = P[4][2]*t101;
+float t78 = P[3][2]*t103;
+float t49 = t45+t46+t47+t48-t63-t77-t78;
+float t50 = P[1][5]*t9;
+float t51 = P[8][5]*t104;
+float t52 = P[0][5]*t105;
+float t53 = P[5][5]*t100;
+float t80 = P[4][5]*t101;
+float t81 = P[2][5]*t102;
+float t82 = P[3][5]*t103;
+float t54 = t50+t51+t52+t53-t80-t81-t82;
+float t55 = t100*t54;
+float t56 = P[1][3]*t9;
+float t57 = P[8][3]*t104;
+float t58 = P[0][3]*t105;
+float t59 = P[5][3]*t100;
+float t83 = P[4][3]*t101;
+float t84 = P[2][3]*t102;
+float t85 = P[3][3]*t103;
+float t60 = t56+t57+t58+t59-t83-t84-t85;
+float t70 = t101*t33;
+float t79 = t102*t49;
+float t86 = t103*t60;
+float t61 = R_LOS+t28+t39+t44+t55-t70-t79-t86; // innovation variance - should always be >= R_LOS
+float t62 = 1.0f/t61;
+
+// Calculate the Kalman gain matrix for the LOS rate about the Y body axis
+float Kfusion[24];
+Kfusion[0] = -t62*(t22+P[0][1]*t9+P[0][5]*t100-P[0][4]*t101-P[0][2]*t102-P[0][3]*t103+P[0][8]*t104);
+Kfusion[1] = -t62*(t23+P[1][5]*t100+P[1][0]*t105-P[1][4]*t101-P[1][2]*t102-P[1][3]*t103+P[1][8]*t104);
+Kfusion[2] = -t62*(-t63+P[2][1]*t9+P[2][5]*t100+P[2][0]*t105-P[2][4]*t101-P[2][3]*t103+P[2][8]*t104);
+Kfusion[3] = -t62*(-t85+P[3][1]*t9+P[3][5]*t100+P[3][0]*t105-P[3][4]*t101-P[3][2]*t102+P[3][8]*t104);
+Kfusion[4] = -t62*(-t67+P[4][1]*t9+P[4][5]*t100+P[4][0]*t105-P[4][2]*t102-P[4][3]*t103+P[4][8]*t104);
+Kfusion[5] = -t62*(t53+P[5][1]*t9+P[5][0]*t105-P[5][4]*t101-P[5][2]*t102-P[5][3]*t103+P[5][8]*t104);
+Kfusion[6] = -t62*(P[6][1]*t9+P[6][5]*t100+P[6][0]*t105-P[6][4]*t101-P[6][2]*t102-P[6][3]*t103+P[6][8]*t104);
+Kfusion[7] = -t62*(P[7][1]*t9+P[7][5]*t100+P[7][0]*t105-P[7][4]*t101-P[7][2]*t102-P[7][3]*t103+P[7][8]*t104);
+Kfusion[8] = -t62*(t35+P[8][1]*t9+P[8][5]*t100+P[8][0]*t105-P[8][4]*t101-P[8][2]*t102-P[8][3]*t103);
+Kfusion[9] = -t62*(P[9][1]*t9+P[9][5]*t100+P[9][0]*t105-P[9][4]*t101-P[9][2]*t102-P[9][3]*t103+P[9][8]*t104);
+Kfusion[10] = -t62*(P[10][1]*t9+P[10][5]*t100+P[10][0]*t105-P[10][4]*t101-P[10][2]*t102-P[10][3]*t103+P[10][8]*t104);
+Kfusion[11] = -t62*(P[11][1]*t9+P[11][5]*t100+P[11][0]*t105-P[11][4]*t101-P[11][2]*t102-P[11][3]*t103+P[11][8]*t104);
+Kfusion[12] = -t62*(P[12][1]*t9+P[12][5]*t100+P[12][0]*t105-P[12][4]*t101-P[12][2]*t102-P[12][3]*t103+P[12][8]*t104);
+Kfusion[13] = -t62*(P[13][1]*t9+P[13][5]*t100+P[13][0]*t105-P[13][4]*t101-P[13][2]*t102-P[13][3]*t103+P[13][8]*t104);
+Kfusion[14] = -t62*(P[14][1]*t9+P[14][5]*t100+P[14][0]*t105-P[14][4]*t101-P[14][2]*t102-P[14][3]*t103+P[14][8]*t104);
+Kfusion[15] = -t62*(P[15][1]*t9+P[15][5]*t100+P[15][0]*t105-P[15][4]*t101-P[15][2]*t102-P[15][3]*t103+P[15][8]*t104);
+Kfusion[16] = -t62*(P[16][1]*t9+P[16][5]*t100+P[16][0]*t105-P[16][4]*t101-P[16][2]*t102-P[16][3]*t103+P[16][8]*t104);
+Kfusion[17] = -t62*(P[17][1]*t9+P[17][5]*t100+P[17][0]*t105-P[17][4]*t101-P[17][2]*t102-P[17][3]*t103+P[17][8]*t104);
+Kfusion[18] = -t62*(P[18][1]*t9+P[18][5]*t100+P[18][0]*t105-P[18][4]*t101-P[18][2]*t102-P[18][3]*t103+P[18][8]*t104);
+Kfusion[19] = -t62*(P[19][1]*t9+P[19][5]*t100+P[19][0]*t105-P[19][4]*t101-P[19][2]*t102-P[19][3]*t103+P[19][8]*t104);
+Kfusion[20] = -t62*(P[20][1]*t9+P[20][5]*t100+P[20][0]*t105-P[20][4]*t101-P[20][2]*t102-P[20][3]*t103+P[20][8]*t104);
+Kfusion[21] = -t62*(P[21][1]*t9+P[21][5]*t100+P[21][0]*t105-P[21][4]*t101-P[21][2]*t102-P[21][3]*t103+P[21][8]*t104);
+Kfusion[22] = -t62*(P[22][1]*t9+P[22][5]*t100+P[22][0]*t105-P[22][4]*t101-P[22][2]*t102-P[22][3]*t103+P[22][8]*t104);
+Kfusion[23] = -t62*(P[23][1]*t9+P[23][5]*t100+P[23][0]*t105-P[23][4]*t101-P[23][2]*t102-P[23][3]*t103+P[23][8]*t104);