コード例 #1
0
    def open_loop(self, current_att_state, current_jd):
        # Current state
        self.mpc_current_quaternion_i2b = current_att_state[0]
        self.mpc_current_omega_b = current_att_state[1]
        self.mpc_current_torque_b = current_att_state[2]

        self.mpc_start_jd = current_jd
        self.mpc_main_count_time = 0

        last_omega_b = self.mpc_current_omega_b
        last_quaternion_q_i2b = self.mpc_current_quaternion_i2b
        last_torque_b = self.mpc_current_torque_b

        last_pos_i, last_vel_i = self.mpc_dynamics_orb.update_state_orbit(current_jd)
        last_sideral = gstime(current_jd)
        last_tar_pos_eci = rotationZ(self.tar_pos_ecef, last_sideral)
        last_rel_vector = last_tar_pos_eci - last_pos_i

        for i in range(self.N_pred_horiz):
            self.mpc_main_count_time += self.mpc_sim_step_prop

            self.mpc_future_jd = self.mpc_start_jd + self.mpc_main_count_time * inv_sec_day
            mpc_decyear = JdToDecyear(self.mpc_future_jd)

            # Dynamics update
            current_q_i2b, current_omega_b = self.mpc_update_attitude(last_omega_b,
                                                                      last_quaternion_q_i2b,
                                                                      last_torque_b)

            current_position_i, current_velocity_i = self.mpc_dynamics_orb.update_state_orbit(self.mpc_future_jd)
            current_sideral = gstime(self.mpc_future_jd)
            current_tar_pos_eci = rotationZ(self.tar_pos_ecef, last_sideral)

            # ECI to Geodetic state
            alt, long, lat = eci_to_geodetic(current_position_i, current_sideral)

            # Get Earth magnetic field
            mag_b = self.get_mag_earth_b(mpc_decyear, alt, long, lat, current_q_i2b, current_sideral)
            #print(mag_b, ', Paso:', i + 1)

            # Control
            current_tar_pos_b = current_q_i2b.frame_conv(current_tar_pos_eci)

            current_torque_b = np.zeros(3)

            # Save last data
            last_omega_b = current_omega_b
            last_quaternion_q_i2b = current_q_i2b
            last_torque_b = current_torque_b
            last_tar_pos_eci = current_tar_pos_eci
        return
コード例 #2
0
    def get_omega_tar(self, current_jd, current_position_i, current_velocity_i,
                      current_q_i2b):
        # omega_target_b error
        sideral = gstime(current_jd)
        tar_pos_i = rotationZ(self.tar_pos_ecef, -sideral)
        vel_gs_i = np.cross(earth_rot_i, tar_pos_i)
        vel_gs_sc = vel_gs_i - current_velocity_i
        pos_gs_sc = tar_pos_i - current_position_i
        mag_omega_gs_sc = np.linalg.norm(vel_gs_sc) / np.linalg.norm(pos_gs_sc)

        unit_vec_pos = pos_gs_sc / np.linalg.norm(pos_gs_sc)
        unit_vec_vel = vel_gs_sc / np.linalg.norm(vel_gs_sc)

        unit_vec_omega_gs_sc = np.cross(unit_vec_pos, unit_vec_vel)
        omega_gs_from_sc_i = mag_omega_gs_sc * unit_vec_omega_gs_sc
        return current_q_i2b.frame_conv(omega_gs_from_sc_i)
コード例 #3
0
 def update_state(self, current_jd, center_object_pos_i, center_object_vel_i,
                  sc_pos_from_center_i, sc_vel_from_center_i, q_i2b, iscenter=False):
     emb_ssb_pos, emb_ssb_vel = self.kernel_spk[0, 3].compute_and_differentiate(current_jd)
     earth_emb_pos, earth_emb_vel = self.kernel_spk[3, 399].compute_and_differentiate(
         current_jd)  # vector from EMB 2 earth
     earth_ssb_pos = emb_ssb_pos + earth_emb_pos
     earth_ssb_vel = emb_ssb_vel + earth_emb_vel
     earth_ssb_pos *= 1000  # km to m
     earth_ssb_vel *= 1000 / 86400.0  # km/day to m/s
     if iscenter:
         return earth_ssb_pos, earth_ssb_vel
     self.current_pos_from_center_i = earth_ssb_pos - center_object_pos_i
     self.current_vel_from_center_i = earth_ssb_vel - center_object_vel_i
     self.current_pos_from_sc_i = self.current_pos_from_center_i - sc_pos_from_center_i
     self.current_vel_from_sc_i = self.current_vel_from_center_i - sc_vel_from_center_i
     self.current_pos_from_sc_b = q_i2b.frame_conv(self.current_pos_from_sc_i)
     self.current_vel_from_sc_b = q_i2b.frame_conv(self.current_vel_from_sc_i)
     self.current_sideral = gstime(current_jd)
コード例 #4
0
    def open_loop(self, current_att_state, current_jd):
        # Current state
        self.mpc_current_quaternion_i2b = current_att_state[0]
        self.mpc_current_omega_b = current_att_state[1]
        self.mpc_current_torque_b = current_att_state[2]

        self.mpc_start_jd = current_jd
        self.mpc_main_count_time = 0

        # Arrays of independent variables of control
        self.mpc_array_jd = self.mpc_start_jd + np.arange(
            0, self.N_pred_horiz) * self.mpc_sim_step_prop * inv_sec_day
        temp = [
            self.mpc_dynamics_orb.update_state_orbit(elem)
            for elem in self.mpc_array_jd
        ]
        self.mpc_array_sc_pos_i = [
            temp[i][0] for i in range(self.N_pred_horiz)
        ]
        self.mpc_array_sc_vel_i = [
            temp[i][1] for i in range(self.N_pred_horiz)
        ]
        self.mpc_array_sideral = [gstime(elem) for elem in self.mpc_array_jd]
        self.mpc_array_tar_pos_i = [
            rotationZ(self.tar_pos_ecef, -k_sideral)
            for k_sideral in self.mpc_array_sideral
        ]
        self.mpc_array_tar_pos_sc_i = [
            self.mpc_array_tar_pos_i[i] - self.mpc_array_sc_pos_i[i]
            for i in range(self.N_pred_horiz)
        ]
        temp = [
            eci_to_geodetic(self.mpc_array_sc_pos_i[i],
                            self.mpc_array_sideral[i])
            for i in range(self.N_pred_horiz)
        ]
        self.mpc_array_alt = [temp[i][0] for i in range(self.N_pred_horiz)]
        self.mpc_array_lon = [temp[i][1] for i in range(self.N_pred_horiz)]
        self.mpc_array_lat = [temp[i][2] for i in range(self.N_pred_horiz)]

        # Get Earth magnetic field
        self.mpc_array_decyear = [
            JdToDecyear(elem) for elem in self.mpc_array_jd
        ]

        self.mpc_array_mag_i = [
            self.get_mag_earth_ned(self.mpc_array_decyear[i],
                                   self.mpc_array_alt[i],
                                   self.mpc_array_lon[i],
                                   self.mpc_array_lat[i],
                                   self.mpc_array_sideral[i])
            for i in range(self.N_pred_horiz)
        ]
        """
        x0 = np.zeros(self.N_pred_horiz-1)
        xl = np.zeros(3*(self.N_pred_horiz-1))
        xu = 1e4*np.ones(3*(self.N_pred_horiz-1))
        bounds = Bounds(xl, xu)      
        res = minimize(self.objetive_function, x0, method='trust-constr', options={'verbose': 1}, bounds=bounds)
        #res = minimize(self.objetive_function, x0, method='SLSQP', options={'ftol': 1e-9, 'disp': True}, bounds=bounds)
        """
        bounds1 = [(-1e-4, 1e-4)] * (3 * (self.N_pred_horiz - 1))

        res = optimize.differential_evolution(self.objective_func,
                                              bounds1,
                                              maxiter=20,
                                              popsize=10,
                                              tol=1e-4)
        return res.x[0:3], res.fun
コード例 #5
0
 def calc_gst(self, current_jd):
     self.current_sideral = gstime(current_jd)
コード例 #6
0
ファイル: Earth.py プロジェクト: spel-uchile/LandingSimulator
 def update_state(self, current_jd):
     self.current_sideral = gstime(current_jd)
コード例 #7
0
    def check_mode(self):
        if self.adcs_mode == DETUMBLING:
            self.omega_b_tar = np.array([0.0, 0.0, 0.0])
            # self.controller.set_gain(self.P_omega, self.I_quat, np.diag([0.0, 0.0, 0.0]))
        elif self.adcs_mode == NAD_POINT:
            print('Nadir pointing mode...')
        elif self.adcs_mode == REF_POINT:
            # Vector direction of the Body frame to point to another vector
            self.b_dir = np.array([0, 0, 1])

            # Vector target from Inertial frame
            i_tar = np.array([1, -1, -1])
            i_tar = i_tar / np.linalg.norm(i_tar)
            self.b_tar_i = i_tar
            self.controller.set_ref_vector_i(i_tar)

            # Vector target from body frame
            self.b_tar_b = self.q_i2b_est.frame_conv(i_tar)
            self.b_tar_b /= np.linalg.norm(self.b_tar_b)

            self.current_theta_e = np.arccos(np.dot(self.b_dir, self.b_tar_b))
            self.vec_u_e = np.cross(self.b_dir, self.b_tar_b)
            self.vec_u_e /= np.linalg.norm(self.vec_u_e)

            self.q_b2b_now2tar.setquaternion(
                [self.vec_u_e, self.current_theta_e])
            self.q_b2b_now2tar.normalize()
            self.q_i2b_tar = self.q_i2b_est * self.q_b2b_now2tar
        elif self.adcs_mode == GS_POINT:
            # omega_target_b error
            sideral = gstime(self.dynamics.simtime.current_jd)
            tar_pos_i = rotationZ(self.tar_pos_ecef, -sideral)
            self.tar_pos_eci = tar_pos_i
            vel_gs_i = np.cross(earth_rot_i, tar_pos_i)
            vel_gs_sc = vel_gs_i - self.dynamics.orbit.current_velocity_i
            pos_sc2tar_i = tar_pos_i - self.dynamics.orbit.current_position_i
            mag_omega_gs_sc = np.linalg.norm(vel_gs_sc) / np.linalg.norm(
                pos_sc2tar_i)

            unit_vec_pos = pos_sc2tar_i / np.linalg.norm(pos_sc2tar_i)
            unit_vec_vel = vel_gs_sc / np.linalg.norm(vel_gs_sc)

            unit_vec_omega_gs_sc = np.cross(unit_vec_pos, unit_vec_vel)
            omega_gs_from_sc_i = mag_omega_gs_sc * unit_vec_omega_gs_sc

            self.omega_b_tar = self.q_i2b_est.frame_conv(omega_gs_from_sc_i)

            # Vector direction of the Body frame to point to another vector
            self.b_dir = np.array([0, 0, 1])
            # Error
            self.b_tar_i = pos_sc2tar_i / np.linalg.norm(pos_sc2tar_i)
            current_tar_pos_b = self.q_i2b_est.frame_conv(pos_sc2tar_i)
            self.b_tar_b = current_tar_pos_b / np.linalg.norm(
                current_tar_pos_b)
            self.current_theta_e = np.arccos(np.dot(self.b_dir, self.b_tar_b))
            self.vec_u_e = np.cross(self.b_dir, self.b_tar_b)
            self.vec_u_e /= np.linalg.norm(self.vec_u_e)

            self.q_b2b_now2tar.setquaternion(
                [self.vec_u_e, self.current_theta_e])
            self.q_b2b_now2tar.normalize()
            self.q_i2b_tar = self.q_i2b_est * self.q_b2b_now2tar
        else:
            print('No mode selected')