-
Notifications
You must be signed in to change notification settings - Fork 1
/
Copy pathfusion-main.m
334 lines (249 loc) · 10.7 KB
/
fusion-main.m
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
% This code contains the EKF based Attitude, Heading, and Reference System (AHRS) for a fighter-jet class of aircraft.
% Sensors: GPS, IMU, Magnetometer, Pitot-tube
clc
clearvars
close all
%% Load all data
[acc_imu, gps_vel, ang_rates, psi_mag,ang_imu,ang_hyb,gps_pose,imu_vel, dt, t] = flight_data();
%count_dt = 1;
% for ii = 1:length(dt)
% if dT(ii)~=0
% dt_gps(count_dt) = dT(ii);
% gps_vel(1,count_dt) = GPS_vel(1,:);
% count_dt = count_dt+1;
% end
% end
dt = ones(10000)*0.02;
t = 0:dt(1):1800;
acc_imu_x = acc_imu(1,:); % Acc Data, z Up to down
acc_imu_y = acc_imu(2,:);
acc_imu_z = acc_imu(3,:);
p_m = ang_rates(1,:); % Gyro Data, Z down
q_m = ang_rates(2,:);
r_m = ang_rates(3,:);
ang_imu_phi = ang_imu(1,:); % IMU angle Data
ang_imu_theta = ang_imu(2,:);
ang_imu_psi = ang_imu(3,:);
ang_hyb_phi = ang_hyb(1,:); % hyb angle Data
ang_hyb_theta = ang_hyb(2,:);
ang_hyb_psi = ang_hyb(3,:);
Gps_data_rate = 1e10/4; % every "" seconds
Imu_data_rate = 1/100; % every "" seconds
Mag_data_rate = 1/100; % every "" seconds
Pitot_data_rate = 1e10; % every "" seconds, high value if no data
gps_vel_N(1) = 0;
gps_vel_E(1) = 0;
gps_vel_D(1) = 0;
vel_gps_N = gps_vel(1,:); % GPS Data, z Up to down
vel_gps_E = gps_vel(2,:);
vel_gps_D = gps_vel(3,:);
%
dv_N = diff(vel_gps_N);
dv_E = diff(vel_gps_E);
dv_D = diff(vel_gps_D);
acc_gps_N = dv_N./dt(1); % Acc derived from GPS
acc_gps_E = dv_E./dt(1);
acc_gps_D = dv_D./dt(1);
g = 9.81;
g_vec = [0;0;g];
count_gps = 1;
count_mag = 1;
count_pitot = 1;
count_imu = 1;
count_pred = 1;
t_gps(count_gps) = 0;
t_imu(count_imu) = 0;
t_mag(count_mag) = 0;
t_pitot(count_pitot) = 0;
%% Parameter Initialization
b_p = 0.001;
b_q = 0.001;
b_r = 0.001;
bias = [b_p,b_q,b_r];
[X,P] = EKF_init(bias); % Filter Initialization
XX(:,1) = X;
PP{1} = P;
phi = X(1);
theta = X(2);
psi = X(3);
b_p = X(4);
b_q = X(5);
b_r = X(6);
for i=1:length(t)
%% Prediction
% Continuous Time x_dot = F_nlin*x + G*w
% Discrete Time x(k+1) = (1 + F_nlin*dt)*x(k) + G*dt*w(k) = Phi(k)*x(k) + Tau(k)*w(k)
%count_pred = count_pred +1;
F_nlin = [(p_m(i) - b_p) + (q_m(i)-b_q)*sin(phi)*tan(theta) + (r_m(i)-b_r)*cos(phi)*tan(theta);
(q_m(i)-b_q)*cos(phi) - (r_m(i)-b_r)*sin(phi);
(q_m(i)-b_q)*sin(phi)/cos(theta) + (r_m(i)-b_r)*cos(phi)/cos(theta);
0;0;0];
F_lin = [((q_m(i)-b_q)*cos(phi)*tan(theta) - (r_m(i)-b_r)*sin(phi)*tan(theta)), (sec(theta)^2)*((q_m(i)-b_q)*sin(phi) + (r_m(i)-b_r)*cos(phi)), 0, -1, -sin(phi)*tan(theta), -cos(phi)*tan(theta);
(-(q_m(i)-b_q)*sin(phi) - (r_m(i)-b_r)*cos(phi)), 0, 0, 0, -cos(phi), sin(phi);
((q_m(i)-b_q)*cos(phi)/cos(theta) - (r_m(i)-b_r)*sin(phi)/cos(theta)), ((q_m(i)-b_q)*sin(phi)*tan(theta)/cos(theta) + (r_m(i)-b_r)*cos(phi)*tan(theta)/cos(theta)), 0, 0, -sin(phi)/cos(theta), -cos(phi)/cos(theta);
0, 0, 0, 0, 0, 0;
0, 0, 0, 0, 0, 0;
0, 0, 0, 0, 0, 0];
G = [-1 -sin(phi)*tan(theta) -cos(phi)*tan(theta) 0 0 0;
0 -cos(phi) sin(phi) 0 0 0;
0 -sin(phi)/cos(theta) -cos(phi)/cos(theta) 0 0 0;
0 0 0 1 0 0;
0 0 0 0 1 0;
0 0 0 0 0 1 ];
err_bound_phi = deg2rad(1);
err_bound_theta = deg2rad(1);
err_bound_psi = deg2rad(0.5);
eps_phi_rate = err_bound_phi;
eps_theta_rate = err_bound_theta;
eps_psi_rate = err_bound_psi;
eps_b_p = 1e-2;
eps_b_q = 1e-2;
eps_b_r = 1e-2;
Q = diag([eps_phi_rate^2,eps_theta_rate^2,eps_psi_rate^2,eps_b_p^2,eps_b_q^2,eps_b_r^2]);
A_stm = eye(6) + F_lin*dt(i);
[X, P] = EKF_prediction(X,P,F_nlin,A_stm,G,Q,dt(i));
phi = X(1); theta = X(2); psi = X(3); b_p = X(4); b_q = X(5); b_r = X(6);
%% Update
del_t_gps = t(i) - t_gps(count_gps);
del_t_pitot = t(i) - t_pitot(count_pitot);
del_t_mag = t(i) - t_mag(count_mag);
if del_t_gps >= Gps_data_rate % Check if GPS data_received, perform update
count_gps = count_gps + 1;
t_gps(count_gps) = t(i);
% gps_pose_N(count_gps) = gps_pose(1,i);
% gps_pose_E(count_gps) = gps_pose(2,i);
% gps_pose_D(count_gps) = gps_pose(3,i);
gps_vel_N(count_gps) = vel_gps_N(i);%(gps_pose_N(count_gps) - gps_pose_N(count_gps-1))/del_t_gps;
gps_acc_N(count_gps) = acc_gps_N(i);%(gps_vel_N(count_gps) - gps_vel_N(count_gps-1))/del_t_gps;
gps_vel_E(count_gps) = vel_gps_E(i);%(gps_pose_E(count_gps) - gps_pose_E(count_gps-1))/del_t_gps;
gps_acc_E(count_gps) = acc_gps_E(i);%(gps_vel_E(count_gps) - gps_vel_E(count_gps-1))/del_t_gps;
gps_vel_D(count_gps) = vel_gps_D(i);%(gps_pose_D(count_gps) - gps_pose_D(count_gps-1))/del_t_gps;
gps_acc_D(count_gps) = acc_gps_D(i);%(gps_vel_D(count_gps) - gps_vel_D(count_gps-1))/del_t_gps;
% GPS-IMU Measurement model
% psi_m = mod(atan2(vel_gps_y(i),vel_gps_x(i)),2*pi);
psi_m = mod(atan2(gps_vel_E(count_gps),gps_vel_N(count_gps)),2*pi);
% r_x_m = acc_gps_x(i)*cos(psi_m) + acc_gps_y(i)*sin(psi_m);% gps acc ?
% r_y_m = -acc_gps_x(i)*sin(psi_m) + acc_gps_y(i)*cos(psi_m);
% r_z_m = acc_gps_z(i) - g;
r_x_m = gps_acc_N(count_gps)*cos(psi_m) + gps_acc_E(count_gps)*sin(psi_m);% gps acc ?
r_y_m = -gps_acc_N(count_gps)*sin(psi_m) + gps_acc_E(count_gps)*cos(psi_m);
r_z_m = gps_acc_D(count_gps) - g;
exprs_1_m = 1*sqrt(r_x_m^2 + r_z_m^2 - acc_imu_x(i)^2);
theta_m = atan((-r_x_m*r_z_m - acc_imu_x(i)*exprs_1_m)/(acc_imu_x(i)^2 - r_z_m^2));
r_theta_m = r_x_m*sin(theta_m) + r_z_m*cos(theta_m);
exprs_2_m = 1*sqrt(r_y_m^2 + r_theta_m^2 - acc_imu_y(i)^2);
phi_m = atan((r_theta_m*r_y_m + acc_imu_y(i)*exprs_2_m)/(acc_imu_y(i)^2 - r_theta_m^2));
Z_gps(:,count_gps) = [phi_m;theta_m;psi_m];
psi_comp = mod(psi,2*pi);
% r_x = acc_gps_x(i)*cos(psi_comp) + acc_gps_y(i)*sin(psi_comp);
% r_y = -acc_gps_x(i)*sin(psi_comp) + acc_gps_y(i)*cos(psi_comp);
% r_z = acc_gps_z(i) - g;
r_x = gps_acc_N(count_gps)*cos(psi_comp) + gps_acc_E(count_gps)*sin(psi_comp);
r_y = -gps_acc_N(count_gps)*sin(psi_comp) + gps_acc_E(count_gps)*cos(psi_comp);
r_z = gps_acc_D(count_gps) - g;
exprs_1 = 1*sqrt(r_x^2 + r_z^2 - acc_imu_x(i)^2);
theta_comp = atan((-r_x*r_z - acc_imu_x(i)*exprs_1)/(acc_imu_x(i)^2 - r_z^2));
r_theta = r_x*sin(theta_comp) + r_z*cos(theta_comp);
exprs_2 = 1*sqrt(r_y^2 + r_theta^2 - acc_imu_y(i)^2);
phi_comp = atan((r_theta*r_y + acc_imu_y(i)*exprs_2)/(acc_imu_y(i)^2 - r_theta^2));
h_gps = [phi_comp;theta_comp;psi_comp];
H_gps = [eye(3,3) zeros(3,3)];
sigma_phi_m = deg2rad(2);
sigma_theta_m = deg2rad(2);
sigma_psi_m = deg2rad(1);
R_gps = diag([sigma_phi_m^2,sigma_theta_m^2,sigma_psi_m^2]);
sensor = 'GPS';
[X, P] = EKF_update(X,P,Z_gps(:,count_gps),H_gps,h_gps,R_gps,sensor);
phi = X(1); theta = X(2); psi = X(3); b_p = X(4); b_q = X(5); b_r = X(6);
end
if del_t_mag >= Mag_data_rate % Check if MAG data_received, perform update
count_mag = count_mag + 1;
t_mag(count_mag) = t(i);
Z_mag(count_mag) = psi_mag(i);
h_mag = psi;
H_mag = [0 0 1 0 0 0];
sigma_psi_mag = deg2rad(1.5);
R_mag = sigma_psi_mag^2;
sensor = 'MAG';
[X, P] = EKF_update(X,P,Z_mag(count_mag),H_mag,h_mag,R_mag,sensor);
phi = X(1); theta = X(2); psi = X(3); b_p = X(4); b_q = X(5); b_r = X(6);
end
if del_t_pitot >= Pitot_data_rate % Check if Pitot data_received, perform update
disp('inside_pitot')
pause(2)
count_pitot = count_pitot + 1;
t_pitot(count_pitot) = t(i);
h_pitor = psi_mag(i);
H_pitot = [0 0 1 0 0 0];
sigma_velx_pitot = rand;
sigma_vely_pitot = rand;
R_pitot = diag([sigma_velx_pitot, sigma_vely_pitot]);
Z_pitot(count_pitot) = [0,0];
sensor = 'Pitot';
[X, P] = EKF_update(X,P,Z_pitot(count_pitot),H_pitot,h_pitot,R_pitot,sensor);
phi = X(1); theta = X(2); psi = X(3); b_p = X(4); b_q = X(5); b_r = X(6);
end
XX(:,i+1) = X;
PP{i+1} = P;
end
%gps_acc_x_f = medfilt1(gps_acc_E,3);
% acc_gps_x_f = medfilt1(acc_gps_x,2);
figure(200)
grid on
subplot(3,1,1)
plot(t,rad2deg(ang_imu_phi(1:length(t))),'k',t,rad2deg(ang_hyb_phi(1:length(t))),'c.',t,rad2deg(XX(1,1:length(t))),'b');
xlim([0 1600]);
legend('IMU', 'HYB','COMPUTED')
%title('Velocity East')
xlabel('Time (s)')
ylabel('Roll: \phi (\circ)')
subplot(3,1,2)
plot(t,rad2deg(ang_imu_theta(1:length(t))),'k',t,rad2deg(ang_hyb_theta(1:length(t))),'c.',t,rad2deg(XX(2,1:length(t))),'b');
xlim([0 1600]);
legend('IMU', 'HYB','COMPUTED')
xlabel('Time (s)')
ylabel('Pitch: \theta (\circ)')
subplot(3,1,3)
plot(t,rad2deg(ang_imu_psi(1:length(t))),'k',t_mag,rad2deg(Z_mag),'c.',t,rad2deg(XX(3,1:length(t))),'b');
legend('IMU', 'Sensor','COMPUTED')
xlim([0 1600]);
xlabel('Time (s)')
ylabel('Yaw: \psi (\circ)')
print(figure(200),'Angles','-depsc');
figure(111)
subplot(3,1,1)
plot(t,rad2deg(XX(4,1:length(t))),'k')
xlim([0 1600]);
xlabel('Time (s)')
ylabel('Roll-rate-bias:b_p(\circ/s)')
subplot(3,1,2)
plot(t,rad2deg(XX(5,1:length(t))),'k')
xlim([0 1600]);
xlabel('Time (s)')
ylabel('Pitch-rate-bias:b_q(\circ/s)')
subplot(3,1,3)
plot(t,rad2deg(XX(6,1:length(t))),'k')
xlim([0 1600]);
xlabel('Time (s)')
ylabel('Yaw-rate-bias:b_r(\circ/s)')
print(figure(111),'bias','-depsc')
count = 0;
for kk=1:13:length(t)
count = count+1;
R_N_B = [cos(ang_imu_psi(kk))*cos(ang_imu_theta(kk)) sin(ang_imu_psi(kk))*cos(ang_imu_theta(kk)) -sin(ang_imu_theta(kk));
cos(ang_imu_psi(kk))*sin(ang_imu_theta(kk))*sin(ang_imu_phi(kk))-sin(ang_imu_psi(kk))*cos(ang_imu_phi(kk)) cos(ang_imu_psi(kk))*cos(ang_imu_phi(kk))+sin(ang_imu_psi(kk))*sin(ang_imu_theta(kk))*sin(ang_imu_phi(kk)) cos(ang_imu_theta(kk))*sin(ang_imu_phi(kk))
sin(ang_imu_psi(kk))*sin(ang_imu_phi(kk))+cos(ang_imu_psi(kk))*sin(ang_imu_theta(kk))*cos(ang_imu_phi(kk)) sin(ang_imu_psi(kk))*sin(ang_imu_theta(kk))*cos(ang_imu_phi(kk))-cos(ang_imu_psi(kk))*sin(ang_imu_phi(kk)) cos(ang_imu_theta(kk))*cos(ang_imu_phi(kk))];
a_g(:,count) = R_N_B*[gps_acc_N(count);gps_acc_E(count);gps_acc_D(count)];
end
figure(100)
subplot(3,1,1)
plot(t,acc_gps_N(1:length(t)),'c.',t,acc_imu_x(1:length(t)),'k')%,t_gps,gps_acc_N,'r')%, t,acc_gps_x(1:length(t)),'m')
subplot(3,1,2)
plot(t,acc_imu_y(1:length(t)),'k',t_gps(1:length(a_g)),a_g(2,:),'r')%,t,acc_gps_E(1:length(t)),'m')
subplot(3,1,3)
plot(t,acc_imu_z(1:length(t)),'k',t_gps(1:length(a_g)),a_g(3,:),'r')%,t,acc_gps_D(1:length(t)),'m')
figure(101) % 3d trajectory
grid on
plot(t, imu_vel(1,1:length(t)),'k',t_gps,gps_vel_N,'b',t,vel_gps_N(1,1:length(t)),'c.');% imu_vel(2,1:13:end),imu_vel(3,1:13:end),'b');
% hold on
% plot3(gps_vel_N,gps_vel_E,gps_vel_D,'k');