Struct MetaAlmanac
pub struct MetaAlmanac {
pub files: Vec<MetaFile>,
}Expand description
A structure to set up an Almanac, with automatic downloading, local storage, checksum checking, and more.
§Behavior
If the URI is a local path, relative or absolute, nothing will be fetched from a remote. Relative paths are relative to the execution folder (i.e. the current working directory). If the URI is a remote path, the MetaAlmanac will first check if the file exists locally. If it exists, it will check that the CRC32 checksum of this file matches that of the specs. If it does not match, the file will be downloaded again. If no CRC32 is provided but the file exists, then the MetaAlmanac will fetch the remote file and overwrite the existing file. The downloaded path will be stored in the “AppData” folder.
:type maybe_path: str, optional :rtype: MetaAlmanac
Fields§
§files: Vec<MetaFile>Implementations§
§impl MetaAlmanac
impl MetaAlmanac
pub fn new(path: &str) -> Result<MetaAlmanac, MetaAlmanacError>
pub fn new(path: &str) -> Result<MetaAlmanac, MetaAlmanacError>
Loads the provided path as a Dhall configuration file and processes each file.
Examples found in repository?
35fn main() -> Result<(), Box<dyn Error>> {
36 pel::init();
37
38 // ====================== //
39 // === ALMANAC SET UP === //
40 // ====================== //
41
42 // Dynamics models require planetary constants and ephemerides to be defined.
43 // Let's start by grabbing those by using ANISE's MetaAlmanac.
44
45 let data_folder: PathBuf = [
46 env!("CARGO_MANIFEST_DIR"),
47 "examples",
48 "06_lunar_orbit_determination",
49 ]
50 .iter()
51 .collect();
52
53 let meta = data_folder.join("metaalmanac.dhall");
54
55 // Load this ephem in the general Almanac we're using for this analysis.
56 let almanac = MetaAlmanac::new(meta.to_string_lossy().as_ref())
57 .map_err(Box::new)?
58 .process(true)
59 .map_err(Box::new)?;
60
61 // Lock the almanac (an Arc is a read only structure).
62 let almanac = Arc::new(almanac);
63
64 // Build a nominal trajectory
65 // TODO: Switch this to a sequence once the OD over a spacecraft sequence is implemented.
66
67 let epoch = Epoch::from_gregorian_utc_at_noon(2024, 2, 29);
68 let moon_j2000 = almanac.frame_info(MOON_J2000)?;
69
70 // To build the trajectory we need to provide a spacecraft template.
71 let orbiter = Spacecraft::builder()
72 .mass(Mass::from_dry_and_prop_masses(1018.0, 900.0))
73 .srp(SRPData {
74 area_m2: 3.9 * 2.7,
75 coeff_reflectivity: 0.96,
76 })
77 .orbit(Orbit::try_keplerian_altitude(
78 150.0, 0.00212, 33.6, 45.0, 45.0, 0.0, epoch, moon_j2000,
79 )?) // Setting a zero orbit here because it's just a template
80 .build();
81
82 // ========================== //
83 // === BUILD NOMINAL TRAJ === //
84 // ========================== //
85
86 // Set up the spacecraft dynamics.
87
88 // Specify that the orbital dynamics must account for the graviational pull of the Earth and the Sun.
89 // The gravity of the Moon will also be accounted for since the spaceraft in a lunar orbit.
90 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![EARTH, SUN, JUPITER_BARYCENTER]);
91
92 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
93 // We're using the GRAIL JGGRX model.
94 let mut jggrx_meta = MetaFile {
95 uri: "http://public-data.nyxspace.com/nyx/models/Luna_jggrx_1500e_sha.tab.gz".to_string(),
96 crc32: Some(0x6bcacda8), // Specifying the CRC32 avoids redownloading it if it's cached.
97 };
98 // And let's download it if we don't have it yet.
99 jggrx_meta.process(true)?;
100
101 // Build the spherical harmonics.
102 // The harmonics must be computed in the body fixed frame.
103 // We're using the long term prediction of the Moon principal axes frame.
104 let moon_pa_frame = MOON_PA_FRAME.with_orient(31008);
105 let sph_harmonics = GravityField::new(GravityFieldData::from_shadr(
106 &jggrx_meta.uri,
107 80,
108 80,
109 true,
110 almanac.frame_info(moon_pa_frame)?,
111 )?);
112
113 // Include the spherical harmonics into the orbital dynamics.
114 orbital_dyn.accel_models.push(sph_harmonics);
115
116 // We define the solar radiation pressure, using the default solar flux and accounting only
117 // for the eclipsing caused by the Earth and Moon.
118 // Note that by default, enabling the SolarPressure model will also enable the estimation of the coefficient of reflectivity.
119 let srp_dyn = SolarPressure::new(vec![MOON_J2000], &almanac)?;
120
121 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
122 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
123 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
124
125 println!("{dynamics}");
126
127 let setup = Propagator::rk89(dynamics.clone(), IntegratorOptions::default());
128
129 let truth_traj = setup
130 .with(orbiter, almanac.clone())
131 .for_duration_with_traj(Unit::Day * 2)?
132 .1;
133
134 // ==================== //
135 // === OD SIMULATOR === //
136 // ==================== //
137
138 // Load the Deep Space Network ground stations.
139 // Nyx allows you to build these at runtime but it's pretty static so we can just load them from YAML.
140 let ground_station_file = data_folder.join("dsn-network.yaml");
141 let devices = GroundStation::load_named(ground_station_file)?;
142
143 let proc_devices = devices.clone();
144
145 // Typical OD software requires that you specify your own tracking schedule or you'll have overlapping measurements.
146 // Nyx can build a tracking schedule for you based on the first station with access.
147 let configs: BTreeMap<String, TrkConfig> =
148 TrkConfig::load_named(data_folder.join("tracking-cfg.yaml"))?;
149
150 // Build the tracking arc simulation to generate a "standard measurement".
151 let mut trk = TrackingArcSim::<Spacecraft, GroundStation>::with_seed(
152 devices.clone(),
153 truth_traj.clone(),
154 configs,
155 123, // Set a seed for reproducibility
156 )?;
157
158 trk.build_schedule(almanac.clone())?;
159 let arc = trk.generate_measurements(almanac.clone())?;
160 // Save the simulated tracking data
161 arc.to_parquet_simple("./data/04_output/06_lunar_simulated_tracking.parquet")?;
162
163 // We'll note that in our case, we have continuous coverage of LRO when the vehicle is not behind the Moon.
164 println!("{arc}");
165
166 // Now that we have simulated measurements, we'll run the orbit determination.
167
168 // ===================== //
169 // === OD ESTIMATION === //
170 // ===================== //
171
172 let sc = SpacecraftUncertainty::builder()
173 .nominal(orbiter)
174 .frame(LocalFrame::RIC)
175 .x_km(0.5)
176 .y_km(0.5)
177 .z_km(0.5)
178 .vx_km_s(5e-3)
179 .vy_km_s(5e-3)
180 .vz_km_s(5e-3)
181 .build();
182
183 // Build the filter initial estimate, which we will reuse in the filter.
184 let initial_estimate = sc.to_estimate()?;
185
186 println!("== FILTER STATE ==\n{orbiter:x}\n{initial_estimate}");
187
188 // Build the SNC in the Moon J2000 frame, specified as a velocity noise over time.
189 let process_noise = ProcessNoise3D::from_velocity_km_s(
190 &[1e-14, 1e-14, 1e-14],
191 1 * Unit::Hour,
192 10 * Unit::Minute,
193 None,
194 );
195
196 println!("{process_noise}");
197
198 // We'll set up the OD process to reject measurements whose residuals are move than 3 sigmas away from what we expect.
199 let odp = SpacecraftKalmanScalarOD::new(
200 setup,
201 KalmanVariant::ReferenceUpdate,
202 Some(ResidRejectCrit::default()),
203 proc_devices,
204 almanac.clone(),
205 )
206 .with_process_noise(process_noise);
207
208 let od_sol = odp.process_arc(initial_estimate, &arc)?;
209
210 let final_est = od_sol.estimates.last().unwrap();
211
212 println!("{final_est}");
213
214 let ric_err = truth_traj
215 .at(final_est.epoch())?
216 .orbit
217 .ric_difference(&final_est.orbital_state())?;
218 println!("== RIC at end ==");
219 println!("RIC Position (m): {:.3}", ric_err.radius_km * 1e3);
220 println!("RIC Velocity (m/s): {:.3}", ric_err.velocity_km_s * 1e3);
221
222 println!(
223 "Num residuals rejected: #{}",
224 od_sol.rejected_residuals().len()
225 );
226 println!(
227 "Percentage within +/-3: {}",
228 od_sol.residual_ratio_within_threshold(3.0).unwrap()
229 );
230 println!("Whitened residuals normal? {}", od_sol.is_normal(None)?);
231 println!("NIS test success? {}", od_sol.is_nis_consistent(None)?);
232
233 od_sol.to_parquet(
234 "./data/04_output/06_lunar_od_results.parquet",
235 ExportCfg::default(),
236 )?;
237
238 let od_trajectory = od_sol.to_traj()?;
239 // Build the RIC difference.
240 od_trajectory.ric_diff_to_parquet(
241 &truth_traj,
242 "./data/04_output/06_lunar_od_truth_error.parquet",
243 ExportCfg::default(),
244 )?;
245
246 Ok(())
247}More examples
35fn main() -> Result<(), Box<dyn Error>> {
36 pel::init();
37
38 // ====================== //
39 // === ALMANAC SET UP === //
40 // ====================== //
41
42 // Dynamics models require planetary constants and ephemerides to be defined.
43 // Let's start by grabbing those by using ANISE's MetaAlmanac.
44
45 let output_folder: PathBuf = [env!("CARGO_MANIFEST_DIR"), "../data", "04_output"]
46 .iter()
47 .collect();
48
49 let data_folder: PathBuf = [env!("CARGO_MANIFEST_DIR"), "examples", "04_lro_od"]
50 .iter()
51 .collect();
52
53 let meta = data_folder.join("lro-dynamics.dhall");
54
55 // Load this ephem in the general Almanac we're using for this analysis.
56 let mut almanac = MetaAlmanac::new(meta.to_string_lossy().as_ref())
57 .map_err(Box::new)?
58 .process(true)
59 .map_err(Box::new)?;
60
61 let mut moon_pc = almanac.get_planetary_data_from_id(MOON).unwrap();
62 moon_pc.mu_km3_s2 = 4902.74987;
63 almanac.set_planetary_data_from_id(MOON, moon_pc).unwrap();
64
65 let mut earth = almanac.get_planetary_data_from_id(EARTH).unwrap();
66 earth.mu_km3_s2 = 398600.436;
67 almanac.set_planetary_data_from_id(EARTH, earth).unwrap();
68
69 // Save this new kernel for reuse.
70 // In an operational context, this would be part of the "Lock" process, and should not change throughout the mission.
71 almanac
72 .planetary_data
73 .values()
74 .next()
75 .unwrap()
76 .save_as(&data_folder.join("lro-specific.pca"), true)?;
77
78 // Lock the almanac (an Arc is a read only structure).
79 let almanac = Arc::new(almanac);
80
81 // Orbit determination requires a Trajectory structure, which can be saved as parquet file.
82 // In our case, the trajectory comes from the BSP file, so we need to build a Trajectory from the almanac directly.
83 // To query the Almanac, we need to build the LRO frame in the J2000 orientation in our case.
84 // Inspecting the LRO BSP in the ANISE GUI shows us that NASA has assigned ID -85 to LRO.
85 let lro_frame = Frame::from_ephem_j2000(-85);
86
87 // To build the trajectory we need to provide a spacecraft template.
88 let sc_template = Spacecraft::builder()
89 .mass(Mass::from_dry_and_prop_masses(1018.0, 900.0)) // Launch masses
90 .srp(SRPData {
91 // SRP configuration is arbitrary, but we will be estimating it anyway.
92 area_m2: 3.9 * 2.7,
93 coeff_reflectivity: 0.96,
94 })
95 .orbit(Orbit::zero(MOON_J2000)) // Setting a zero orbit here because it's just a template
96 .build();
97 // Now we can build the trajectory from the BSP file.
98 // We'll arbitrarily set the tracking arc to 24 hours with a five second time step.
99 let traj_as_flown = Traj::from_bsp(
100 lro_frame,
101 MOON_J2000,
102 almanac.clone(),
103 sc_template,
104 5.seconds(),
105 Some(Epoch::from_str("2024-01-01 00:00:00 UTC")?),
106 Some(Epoch::from_str("2024-01-02 00:00:00 UTC")?),
107 Aberration::LT,
108 Some("LRO".to_string()),
109 )?;
110
111 println!("{traj_as_flown}");
112
113 // ====================== //
114 // === MODEL MATCHING === //
115 // ====================== //
116
117 // Set up the spacecraft dynamics.
118
119 // Specify that the orbital dynamics must account for the graviational pull of the Earth and the Sun.
120 // The gravity of the Moon will also be accounted for since the spaceraft in a lunar orbit.
121 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![EARTH, SUN, JUPITER_BARYCENTER]);
122
123 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
124 // We're using the GRAIL JGGRX model.
125 let mut jggrx_meta = MetaFile {
126 uri: "http://public-data.nyxspace.com/nyx/models/Luna_jggrx_1500e_sha.tab.gz".to_string(),
127 crc32: Some(0x6bcacda8), // Specifying the CRC32 avoids redownloading it if it's cached.
128 };
129 // And let's download it if we don't have it yet.
130 jggrx_meta.process(true)?;
131
132 // Build the spherical harmonics.
133 // The harmonics must be computed in the body fixed frame.
134 // We're using the long term prediction of the Moon principal axes frame.
135 let moon_pa_frame = MOON_PA_FRAME.with_orient(31008);
136 let sph_harmonics = GravityField::new(GravityFieldData::from_shadr(
137 &jggrx_meta.uri,
138 80,
139 80,
140 true,
141 almanac.frame_info(moon_pa_frame)?,
142 )?);
143
144 // Include the spherical harmonics into the orbital dynamics.
145 orbital_dyn.accel_models.push(sph_harmonics);
146
147 // We define the solar radiation pressure, using the default solar flux and accounting only
148 // for the eclipsing caused by the Earth and Moon.
149 // Note that by default, enabling the SolarPressure model will also enable the estimation of the coefficient of reflectivity.
150 let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], &almanac)?;
151
152 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
153 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
154 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
155
156 println!("{dynamics}");
157
158 // Now we can build the propagator.
159 let setup = Propagator::default_dp78(dynamics.clone());
160
161 // For reference, let's build the trajectory with Nyx's models from that LRO state.
162 let (sim_final, traj_as_sim) = setup
163 .with(*traj_as_flown.first(), almanac.clone())
164 .until_epoch_with_traj(traj_as_flown.last().epoch())?;
165
166 println!("SIM INIT: {:x}", traj_as_flown.first());
167 println!("SIM FINAL: {sim_final:x}");
168 // Compute RIC difference between SIM and LRO ephem
169 let sim_lro_delta = sim_final
170 .orbit
171 .ric_difference(&traj_as_flown.last().orbit)?;
172 println!("{traj_as_sim}");
173 println!(
174 "SIM v LRO - RIC Position (m): {:.3}",
175 sim_lro_delta.radius_km * 1e3
176 );
177 println!(
178 "SIM v LRO - RIC Velocity (m/s): {:.3}",
179 sim_lro_delta.velocity_km_s * 1e3
180 );
181
182 traj_as_sim.ric_diff_to_parquet(
183 &traj_as_flown,
184 output_folder.join("./04_lro_sim_truth_error.parquet"),
185 ExportCfg::default(),
186 )?;
187
188 // ==================== //
189 // === OD SIMULATOR === //
190 // ==================== //
191
192 // After quite some time trying to exactly match the model, we still end up with an oscillatory difference on the order of 150 meters between the propagated state
193 // and the truth LRO state.
194
195 // Therefore, we will actually run an estimation from a dispersed LRO state.
196 // The sc_seed is the true LRO state from the BSP.
197 let sc_seed = *traj_as_flown.first();
198
199 // Load the Deep Space Network ground stations.
200 // Nyx allows you to build these at runtime but it's pretty static so we can just load them from YAML.
201 let ground_station_file: PathBuf = [
202 env!("CARGO_MANIFEST_DIR"),
203 "examples",
204 "04_lro_od",
205 "dsn-network.yaml",
206 ]
207 .iter()
208 .collect();
209
210 let devices = GroundStation::load_named(ground_station_file)?;
211
212 let mut proc_devices = devices.clone();
213
214 // Increase the noise in the devices to accept more measurements.
215 for gs in proc_devices.values_mut() {
216 if let Some(noise) = &mut gs
217 .stochastic_noises
218 .as_mut()
219 .unwrap()
220 .get_mut(&MeasurementType::Range)
221 {
222 *noise.white_noise.as_mut().unwrap() *= 3.0;
223 }
224 }
225
226 // Typical OD software requires that you specify your own tracking schedule or you'll have overlapping measurements.
227 // Nyx can build a tracking schedule for you based on the first station with access.
228 let trkconfg_yaml: PathBuf = [
229 env!("CARGO_MANIFEST_DIR"),
230 "examples",
231 "04_lro_od",
232 "tracking-cfg.yaml",
233 ]
234 .iter()
235 .collect();
236
237 let configs: BTreeMap<String, TrkConfig> = TrkConfig::load_named(trkconfg_yaml)?;
238
239 // Build the tracking arc simulation to generate a "standard measurement".
240 let mut trk = TrackingArcSim::<Spacecraft, GroundStation>::with_seed(
241 devices.clone(),
242 traj_as_flown.clone(),
243 configs,
244 123, // Set a seed for reproducibility
245 )?;
246
247 trk.build_schedule(almanac.clone())?;
248 let arc = trk.generate_measurements(almanac.clone())?;
249 // Save the simulated tracking data
250 arc.to_parquet_simple(output_folder.join("04_lro_simulated_tracking.parquet"))?;
251
252 // We'll note that in our case, we have continuous coverage of LRO when the vehicle is not behind the Moon.
253 println!("{arc}");
254
255 // Now that we have simulated measurements, we'll run the orbit determination.
256
257 // ===================== //
258 // === OD ESTIMATION === //
259 // ===================== //
260
261 let sc = SpacecraftUncertainty::builder()
262 .nominal(sc_seed)
263 .frame(LocalFrame::RIC)
264 .x_km(0.5)
265 .y_km(0.5)
266 .z_km(0.5)
267 .vx_km_s(5e-3)
268 .vy_km_s(5e-3)
269 .vz_km_s(5e-3)
270 .build();
271
272 // Build the filter initial estimate, which we will reuse in the filter.
273 let mut initial_estimate = sc.to_estimate()?;
274 initial_estimate.covar *= 3.0;
275
276 println!("== FILTER STATE ==\n{sc_seed:x}\n{initial_estimate}");
277
278 // Build the SNC in the Moon J2000 frame, specified as a velocity noise over time.
279 let process_noise = ProcessNoise3D::from_velocity_km_s(
280 &[1e-12, 1e-12, 1e-12],
281 1 * Unit::Hour,
282 10 * Unit::Minute,
283 None,
284 );
285
286 println!("{process_noise}");
287
288 // We'll set up the OD process to reject measurements whose residuals are move than 3 sigmas away from what we expect.
289 let odp = SpacecraftKalmanOD::new(
290 setup,
291 KalmanVariant::ReferenceUpdate,
292 Some(ResidRejectCrit::default()),
293 proc_devices,
294 almanac.clone(),
295 )
296 .with_process_noise(process_noise);
297
298 let od_sol = odp.process_arc(initial_estimate, &arc)?;
299
300 let final_est = od_sol.estimates.last().unwrap();
301
302 println!("{final_est}");
303
304 let ric_err = traj_as_flown
305 .at(final_est.epoch())?
306 .orbit
307 .ric_difference(&final_est.orbital_state())?;
308 println!("== RIC at end ==");
309 println!("RIC Position (m): {:.3}", ric_err.radius_km * 1e3);
310 println!("RIC Velocity (m/s): {:.3}", ric_err.velocity_km_s * 1e3);
311
312 println!(
313 "Num residuals rejected: #{}",
314 od_sol.rejected_residuals().len()
315 );
316 println!(
317 "Percentage within +/-3: {}",
318 od_sol.residual_ratio_within_threshold(3.0).unwrap()
319 );
320 println!("Ratios normal? {}", od_sol.is_normal(None).unwrap());
321
322 od_sol.to_parquet(
323 output_folder.join("04_lro_od_results.parquet"),
324 ExportCfg::default(),
325 )?;
326
327 // Create the ephemeris
328 let ephem = od_sol.to_ephemeris("LRO rebuilt".to_string());
329 let ephem_start = ephem.start_epoch().unwrap();
330 let ephem_end = ephem.end_epoch().unwrap();
331 // Check that the covariance is PSD throughout the ephemeris by interpolating it.
332 for epoch in TimeSeries::inclusive(ephem_start, ephem_end, Unit::Minute * 5) {
333 ephem
334 .covar_at(
335 epoch,
336 anise::ephemerides::ephemeris::LocalFrame::RIC,
337 &almanac,
338 )
339 .unwrap_or_else(|e| panic!("covar not PSD at {epoch}: {e}"));
340 }
341 // Export as BSP!
342 ephem
343 .write_spice_bsp(
344 -85,
345 output_folder.join("04_lro_rebuilt.bsp").to_str().unwrap(),
346 None,
347 )
348 .expect("could not built BSP");
349 let new_almanac = Almanac::default()
350 .load(output_folder.join("04_lro_rebuilt.bsp").to_str().unwrap())
351 .unwrap();
352 new_almanac.describe(None, None, None, None, None, None, None, None);
353 let (spk_start, spk_end) = new_almanac.spk_domain(-85).unwrap();
354
355 assert!((ephem_start - spk_start).abs() < Unit::Microsecond * 1);
356 assert!((ephem_end - spk_end).abs() < Unit::Microsecond * 1);
357
358 // In our case, we have the truth trajectory from NASA.
359 // So we can compute the RIC state difference between the real LRO ephem and what we've just estimated.
360 // Export the OD trajectory first.
361 let od_trajectory = od_sol.to_traj()?;
362 // Build the RIC difference.
363 od_trajectory.ric_diff_to_parquet(
364 &traj_as_flown,
365 output_folder.join("04_lro_od_truth_error.parquet"),
366 ExportCfg::default(),
367 )?;
368
369 Ok(())
370}pub fn process(&mut self, autodelete: bool) -> Result<Almanac, AlmanacError>
pub fn process(&mut self, autodelete: bool) -> Result<Almanac, AlmanacError>
Fetch all of the URIs and return a loaded Almanac
When downloading the data, ANISE will create a temporarily lock file to prevent race conditions
where multiple processes download the data at the same time. Set autodelete to true to delete
this lock file if a dead lock is detected after 10 seconds. Set this flag to false if you have
more than ten processes which may attempt to download files in parallel.
Examples found in repository?
35fn main() -> Result<(), Box<dyn Error>> {
36 pel::init();
37
38 // ====================== //
39 // === ALMANAC SET UP === //
40 // ====================== //
41
42 // Dynamics models require planetary constants and ephemerides to be defined.
43 // Let's start by grabbing those by using ANISE's MetaAlmanac.
44
45 let data_folder: PathBuf = [
46 env!("CARGO_MANIFEST_DIR"),
47 "examples",
48 "06_lunar_orbit_determination",
49 ]
50 .iter()
51 .collect();
52
53 let meta = data_folder.join("metaalmanac.dhall");
54
55 // Load this ephem in the general Almanac we're using for this analysis.
56 let almanac = MetaAlmanac::new(meta.to_string_lossy().as_ref())
57 .map_err(Box::new)?
58 .process(true)
59 .map_err(Box::new)?;
60
61 // Lock the almanac (an Arc is a read only structure).
62 let almanac = Arc::new(almanac);
63
64 // Build a nominal trajectory
65 // TODO: Switch this to a sequence once the OD over a spacecraft sequence is implemented.
66
67 let epoch = Epoch::from_gregorian_utc_at_noon(2024, 2, 29);
68 let moon_j2000 = almanac.frame_info(MOON_J2000)?;
69
70 // To build the trajectory we need to provide a spacecraft template.
71 let orbiter = Spacecraft::builder()
72 .mass(Mass::from_dry_and_prop_masses(1018.0, 900.0))
73 .srp(SRPData {
74 area_m2: 3.9 * 2.7,
75 coeff_reflectivity: 0.96,
76 })
77 .orbit(Orbit::try_keplerian_altitude(
78 150.0, 0.00212, 33.6, 45.0, 45.0, 0.0, epoch, moon_j2000,
79 )?) // Setting a zero orbit here because it's just a template
80 .build();
81
82 // ========================== //
83 // === BUILD NOMINAL TRAJ === //
84 // ========================== //
85
86 // Set up the spacecraft dynamics.
87
88 // Specify that the orbital dynamics must account for the graviational pull of the Earth and the Sun.
89 // The gravity of the Moon will also be accounted for since the spaceraft in a lunar orbit.
90 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![EARTH, SUN, JUPITER_BARYCENTER]);
91
92 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
93 // We're using the GRAIL JGGRX model.
94 let mut jggrx_meta = MetaFile {
95 uri: "http://public-data.nyxspace.com/nyx/models/Luna_jggrx_1500e_sha.tab.gz".to_string(),
96 crc32: Some(0x6bcacda8), // Specifying the CRC32 avoids redownloading it if it's cached.
97 };
98 // And let's download it if we don't have it yet.
99 jggrx_meta.process(true)?;
100
101 // Build the spherical harmonics.
102 // The harmonics must be computed in the body fixed frame.
103 // We're using the long term prediction of the Moon principal axes frame.
104 let moon_pa_frame = MOON_PA_FRAME.with_orient(31008);
105 let sph_harmonics = GravityField::new(GravityFieldData::from_shadr(
106 &jggrx_meta.uri,
107 80,
108 80,
109 true,
110 almanac.frame_info(moon_pa_frame)?,
111 )?);
112
113 // Include the spherical harmonics into the orbital dynamics.
114 orbital_dyn.accel_models.push(sph_harmonics);
115
116 // We define the solar radiation pressure, using the default solar flux and accounting only
117 // for the eclipsing caused by the Earth and Moon.
118 // Note that by default, enabling the SolarPressure model will also enable the estimation of the coefficient of reflectivity.
119 let srp_dyn = SolarPressure::new(vec![MOON_J2000], &almanac)?;
120
121 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
122 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
123 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
124
125 println!("{dynamics}");
126
127 let setup = Propagator::rk89(dynamics.clone(), IntegratorOptions::default());
128
129 let truth_traj = setup
130 .with(orbiter, almanac.clone())
131 .for_duration_with_traj(Unit::Day * 2)?
132 .1;
133
134 // ==================== //
135 // === OD SIMULATOR === //
136 // ==================== //
137
138 // Load the Deep Space Network ground stations.
139 // Nyx allows you to build these at runtime but it's pretty static so we can just load them from YAML.
140 let ground_station_file = data_folder.join("dsn-network.yaml");
141 let devices = GroundStation::load_named(ground_station_file)?;
142
143 let proc_devices = devices.clone();
144
145 // Typical OD software requires that you specify your own tracking schedule or you'll have overlapping measurements.
146 // Nyx can build a tracking schedule for you based on the first station with access.
147 let configs: BTreeMap<String, TrkConfig> =
148 TrkConfig::load_named(data_folder.join("tracking-cfg.yaml"))?;
149
150 // Build the tracking arc simulation to generate a "standard measurement".
151 let mut trk = TrackingArcSim::<Spacecraft, GroundStation>::with_seed(
152 devices.clone(),
153 truth_traj.clone(),
154 configs,
155 123, // Set a seed for reproducibility
156 )?;
157
158 trk.build_schedule(almanac.clone())?;
159 let arc = trk.generate_measurements(almanac.clone())?;
160 // Save the simulated tracking data
161 arc.to_parquet_simple("./data/04_output/06_lunar_simulated_tracking.parquet")?;
162
163 // We'll note that in our case, we have continuous coverage of LRO when the vehicle is not behind the Moon.
164 println!("{arc}");
165
166 // Now that we have simulated measurements, we'll run the orbit determination.
167
168 // ===================== //
169 // === OD ESTIMATION === //
170 // ===================== //
171
172 let sc = SpacecraftUncertainty::builder()
173 .nominal(orbiter)
174 .frame(LocalFrame::RIC)
175 .x_km(0.5)
176 .y_km(0.5)
177 .z_km(0.5)
178 .vx_km_s(5e-3)
179 .vy_km_s(5e-3)
180 .vz_km_s(5e-3)
181 .build();
182
183 // Build the filter initial estimate, which we will reuse in the filter.
184 let initial_estimate = sc.to_estimate()?;
185
186 println!("== FILTER STATE ==\n{orbiter:x}\n{initial_estimate}");
187
188 // Build the SNC in the Moon J2000 frame, specified as a velocity noise over time.
189 let process_noise = ProcessNoise3D::from_velocity_km_s(
190 &[1e-14, 1e-14, 1e-14],
191 1 * Unit::Hour,
192 10 * Unit::Minute,
193 None,
194 );
195
196 println!("{process_noise}");
197
198 // We'll set up the OD process to reject measurements whose residuals are move than 3 sigmas away from what we expect.
199 let odp = SpacecraftKalmanScalarOD::new(
200 setup,
201 KalmanVariant::ReferenceUpdate,
202 Some(ResidRejectCrit::default()),
203 proc_devices,
204 almanac.clone(),
205 )
206 .with_process_noise(process_noise);
207
208 let od_sol = odp.process_arc(initial_estimate, &arc)?;
209
210 let final_est = od_sol.estimates.last().unwrap();
211
212 println!("{final_est}");
213
214 let ric_err = truth_traj
215 .at(final_est.epoch())?
216 .orbit
217 .ric_difference(&final_est.orbital_state())?;
218 println!("== RIC at end ==");
219 println!("RIC Position (m): {:.3}", ric_err.radius_km * 1e3);
220 println!("RIC Velocity (m/s): {:.3}", ric_err.velocity_km_s * 1e3);
221
222 println!(
223 "Num residuals rejected: #{}",
224 od_sol.rejected_residuals().len()
225 );
226 println!(
227 "Percentage within +/-3: {}",
228 od_sol.residual_ratio_within_threshold(3.0).unwrap()
229 );
230 println!("Whitened residuals normal? {}", od_sol.is_normal(None)?);
231 println!("NIS test success? {}", od_sol.is_nis_consistent(None)?);
232
233 od_sol.to_parquet(
234 "./data/04_output/06_lunar_od_results.parquet",
235 ExportCfg::default(),
236 )?;
237
238 let od_trajectory = od_sol.to_traj()?;
239 // Build the RIC difference.
240 od_trajectory.ric_diff_to_parquet(
241 &truth_traj,
242 "./data/04_output/06_lunar_od_truth_error.parquet",
243 ExportCfg::default(),
244 )?;
245
246 Ok(())
247}More examples
35fn main() -> Result<(), Box<dyn Error>> {
36 pel::init();
37
38 // ====================== //
39 // === ALMANAC SET UP === //
40 // ====================== //
41
42 // Dynamics models require planetary constants and ephemerides to be defined.
43 // Let's start by grabbing those by using ANISE's MetaAlmanac.
44
45 let output_folder: PathBuf = [env!("CARGO_MANIFEST_DIR"), "../data", "04_output"]
46 .iter()
47 .collect();
48
49 let data_folder: PathBuf = [env!("CARGO_MANIFEST_DIR"), "examples", "04_lro_od"]
50 .iter()
51 .collect();
52
53 let meta = data_folder.join("lro-dynamics.dhall");
54
55 // Load this ephem in the general Almanac we're using for this analysis.
56 let mut almanac = MetaAlmanac::new(meta.to_string_lossy().as_ref())
57 .map_err(Box::new)?
58 .process(true)
59 .map_err(Box::new)?;
60
61 let mut moon_pc = almanac.get_planetary_data_from_id(MOON).unwrap();
62 moon_pc.mu_km3_s2 = 4902.74987;
63 almanac.set_planetary_data_from_id(MOON, moon_pc).unwrap();
64
65 let mut earth = almanac.get_planetary_data_from_id(EARTH).unwrap();
66 earth.mu_km3_s2 = 398600.436;
67 almanac.set_planetary_data_from_id(EARTH, earth).unwrap();
68
69 // Save this new kernel for reuse.
70 // In an operational context, this would be part of the "Lock" process, and should not change throughout the mission.
71 almanac
72 .planetary_data
73 .values()
74 .next()
75 .unwrap()
76 .save_as(&data_folder.join("lro-specific.pca"), true)?;
77
78 // Lock the almanac (an Arc is a read only structure).
79 let almanac = Arc::new(almanac);
80
81 // Orbit determination requires a Trajectory structure, which can be saved as parquet file.
82 // In our case, the trajectory comes from the BSP file, so we need to build a Trajectory from the almanac directly.
83 // To query the Almanac, we need to build the LRO frame in the J2000 orientation in our case.
84 // Inspecting the LRO BSP in the ANISE GUI shows us that NASA has assigned ID -85 to LRO.
85 let lro_frame = Frame::from_ephem_j2000(-85);
86
87 // To build the trajectory we need to provide a spacecraft template.
88 let sc_template = Spacecraft::builder()
89 .mass(Mass::from_dry_and_prop_masses(1018.0, 900.0)) // Launch masses
90 .srp(SRPData {
91 // SRP configuration is arbitrary, but we will be estimating it anyway.
92 area_m2: 3.9 * 2.7,
93 coeff_reflectivity: 0.96,
94 })
95 .orbit(Orbit::zero(MOON_J2000)) // Setting a zero orbit here because it's just a template
96 .build();
97 // Now we can build the trajectory from the BSP file.
98 // We'll arbitrarily set the tracking arc to 24 hours with a five second time step.
99 let traj_as_flown = Traj::from_bsp(
100 lro_frame,
101 MOON_J2000,
102 almanac.clone(),
103 sc_template,
104 5.seconds(),
105 Some(Epoch::from_str("2024-01-01 00:00:00 UTC")?),
106 Some(Epoch::from_str("2024-01-02 00:00:00 UTC")?),
107 Aberration::LT,
108 Some("LRO".to_string()),
109 )?;
110
111 println!("{traj_as_flown}");
112
113 // ====================== //
114 // === MODEL MATCHING === //
115 // ====================== //
116
117 // Set up the spacecraft dynamics.
118
119 // Specify that the orbital dynamics must account for the graviational pull of the Earth and the Sun.
120 // The gravity of the Moon will also be accounted for since the spaceraft in a lunar orbit.
121 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![EARTH, SUN, JUPITER_BARYCENTER]);
122
123 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
124 // We're using the GRAIL JGGRX model.
125 let mut jggrx_meta = MetaFile {
126 uri: "http://public-data.nyxspace.com/nyx/models/Luna_jggrx_1500e_sha.tab.gz".to_string(),
127 crc32: Some(0x6bcacda8), // Specifying the CRC32 avoids redownloading it if it's cached.
128 };
129 // And let's download it if we don't have it yet.
130 jggrx_meta.process(true)?;
131
132 // Build the spherical harmonics.
133 // The harmonics must be computed in the body fixed frame.
134 // We're using the long term prediction of the Moon principal axes frame.
135 let moon_pa_frame = MOON_PA_FRAME.with_orient(31008);
136 let sph_harmonics = GravityField::new(GravityFieldData::from_shadr(
137 &jggrx_meta.uri,
138 80,
139 80,
140 true,
141 almanac.frame_info(moon_pa_frame)?,
142 )?);
143
144 // Include the spherical harmonics into the orbital dynamics.
145 orbital_dyn.accel_models.push(sph_harmonics);
146
147 // We define the solar radiation pressure, using the default solar flux and accounting only
148 // for the eclipsing caused by the Earth and Moon.
149 // Note that by default, enabling the SolarPressure model will also enable the estimation of the coefficient of reflectivity.
150 let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], &almanac)?;
151
152 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
153 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
154 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
155
156 println!("{dynamics}");
157
158 // Now we can build the propagator.
159 let setup = Propagator::default_dp78(dynamics.clone());
160
161 // For reference, let's build the trajectory with Nyx's models from that LRO state.
162 let (sim_final, traj_as_sim) = setup
163 .with(*traj_as_flown.first(), almanac.clone())
164 .until_epoch_with_traj(traj_as_flown.last().epoch())?;
165
166 println!("SIM INIT: {:x}", traj_as_flown.first());
167 println!("SIM FINAL: {sim_final:x}");
168 // Compute RIC difference between SIM and LRO ephem
169 let sim_lro_delta = sim_final
170 .orbit
171 .ric_difference(&traj_as_flown.last().orbit)?;
172 println!("{traj_as_sim}");
173 println!(
174 "SIM v LRO - RIC Position (m): {:.3}",
175 sim_lro_delta.radius_km * 1e3
176 );
177 println!(
178 "SIM v LRO - RIC Velocity (m/s): {:.3}",
179 sim_lro_delta.velocity_km_s * 1e3
180 );
181
182 traj_as_sim.ric_diff_to_parquet(
183 &traj_as_flown,
184 output_folder.join("./04_lro_sim_truth_error.parquet"),
185 ExportCfg::default(),
186 )?;
187
188 // ==================== //
189 // === OD SIMULATOR === //
190 // ==================== //
191
192 // After quite some time trying to exactly match the model, we still end up with an oscillatory difference on the order of 150 meters between the propagated state
193 // and the truth LRO state.
194
195 // Therefore, we will actually run an estimation from a dispersed LRO state.
196 // The sc_seed is the true LRO state from the BSP.
197 let sc_seed = *traj_as_flown.first();
198
199 // Load the Deep Space Network ground stations.
200 // Nyx allows you to build these at runtime but it's pretty static so we can just load them from YAML.
201 let ground_station_file: PathBuf = [
202 env!("CARGO_MANIFEST_DIR"),
203 "examples",
204 "04_lro_od",
205 "dsn-network.yaml",
206 ]
207 .iter()
208 .collect();
209
210 let devices = GroundStation::load_named(ground_station_file)?;
211
212 let mut proc_devices = devices.clone();
213
214 // Increase the noise in the devices to accept more measurements.
215 for gs in proc_devices.values_mut() {
216 if let Some(noise) = &mut gs
217 .stochastic_noises
218 .as_mut()
219 .unwrap()
220 .get_mut(&MeasurementType::Range)
221 {
222 *noise.white_noise.as_mut().unwrap() *= 3.0;
223 }
224 }
225
226 // Typical OD software requires that you specify your own tracking schedule or you'll have overlapping measurements.
227 // Nyx can build a tracking schedule for you based on the first station with access.
228 let trkconfg_yaml: PathBuf = [
229 env!("CARGO_MANIFEST_DIR"),
230 "examples",
231 "04_lro_od",
232 "tracking-cfg.yaml",
233 ]
234 .iter()
235 .collect();
236
237 let configs: BTreeMap<String, TrkConfig> = TrkConfig::load_named(trkconfg_yaml)?;
238
239 // Build the tracking arc simulation to generate a "standard measurement".
240 let mut trk = TrackingArcSim::<Spacecraft, GroundStation>::with_seed(
241 devices.clone(),
242 traj_as_flown.clone(),
243 configs,
244 123, // Set a seed for reproducibility
245 )?;
246
247 trk.build_schedule(almanac.clone())?;
248 let arc = trk.generate_measurements(almanac.clone())?;
249 // Save the simulated tracking data
250 arc.to_parquet_simple(output_folder.join("04_lro_simulated_tracking.parquet"))?;
251
252 // We'll note that in our case, we have continuous coverage of LRO when the vehicle is not behind the Moon.
253 println!("{arc}");
254
255 // Now that we have simulated measurements, we'll run the orbit determination.
256
257 // ===================== //
258 // === OD ESTIMATION === //
259 // ===================== //
260
261 let sc = SpacecraftUncertainty::builder()
262 .nominal(sc_seed)
263 .frame(LocalFrame::RIC)
264 .x_km(0.5)
265 .y_km(0.5)
266 .z_km(0.5)
267 .vx_km_s(5e-3)
268 .vy_km_s(5e-3)
269 .vz_km_s(5e-3)
270 .build();
271
272 // Build the filter initial estimate, which we will reuse in the filter.
273 let mut initial_estimate = sc.to_estimate()?;
274 initial_estimate.covar *= 3.0;
275
276 println!("== FILTER STATE ==\n{sc_seed:x}\n{initial_estimate}");
277
278 // Build the SNC in the Moon J2000 frame, specified as a velocity noise over time.
279 let process_noise = ProcessNoise3D::from_velocity_km_s(
280 &[1e-12, 1e-12, 1e-12],
281 1 * Unit::Hour,
282 10 * Unit::Minute,
283 None,
284 );
285
286 println!("{process_noise}");
287
288 // We'll set up the OD process to reject measurements whose residuals are move than 3 sigmas away from what we expect.
289 let odp = SpacecraftKalmanOD::new(
290 setup,
291 KalmanVariant::ReferenceUpdate,
292 Some(ResidRejectCrit::default()),
293 proc_devices,
294 almanac.clone(),
295 )
296 .with_process_noise(process_noise);
297
298 let od_sol = odp.process_arc(initial_estimate, &arc)?;
299
300 let final_est = od_sol.estimates.last().unwrap();
301
302 println!("{final_est}");
303
304 let ric_err = traj_as_flown
305 .at(final_est.epoch())?
306 .orbit
307 .ric_difference(&final_est.orbital_state())?;
308 println!("== RIC at end ==");
309 println!("RIC Position (m): {:.3}", ric_err.radius_km * 1e3);
310 println!("RIC Velocity (m/s): {:.3}", ric_err.velocity_km_s * 1e3);
311
312 println!(
313 "Num residuals rejected: #{}",
314 od_sol.rejected_residuals().len()
315 );
316 println!(
317 "Percentage within +/-3: {}",
318 od_sol.residual_ratio_within_threshold(3.0).unwrap()
319 );
320 println!("Ratios normal? {}", od_sol.is_normal(None).unwrap());
321
322 od_sol.to_parquet(
323 output_folder.join("04_lro_od_results.parquet"),
324 ExportCfg::default(),
325 )?;
326
327 // Create the ephemeris
328 let ephem = od_sol.to_ephemeris("LRO rebuilt".to_string());
329 let ephem_start = ephem.start_epoch().unwrap();
330 let ephem_end = ephem.end_epoch().unwrap();
331 // Check that the covariance is PSD throughout the ephemeris by interpolating it.
332 for epoch in TimeSeries::inclusive(ephem_start, ephem_end, Unit::Minute * 5) {
333 ephem
334 .covar_at(
335 epoch,
336 anise::ephemerides::ephemeris::LocalFrame::RIC,
337 &almanac,
338 )
339 .unwrap_or_else(|e| panic!("covar not PSD at {epoch}: {e}"));
340 }
341 // Export as BSP!
342 ephem
343 .write_spice_bsp(
344 -85,
345 output_folder.join("04_lro_rebuilt.bsp").to_str().unwrap(),
346 None,
347 )
348 .expect("could not built BSP");
349 let new_almanac = Almanac::default()
350 .load(output_folder.join("04_lro_rebuilt.bsp").to_str().unwrap())
351 .unwrap();
352 new_almanac.describe(None, None, None, None, None, None, None, None);
353 let (spk_start, spk_end) = new_almanac.spk_domain(-85).unwrap();
354
355 assert!((ephem_start - spk_start).abs() < Unit::Microsecond * 1);
356 assert!((ephem_end - spk_end).abs() < Unit::Microsecond * 1);
357
358 // In our case, we have the truth trajectory from NASA.
359 // So we can compute the RIC state difference between the real LRO ephem and what we've just estimated.
360 // Export the OD trajectory first.
361 let od_trajectory = od_sol.to_traj()?;
362 // Build the RIC difference.
363 od_trajectory.ric_diff_to_parquet(
364 &traj_as_flown,
365 output_folder.join("04_lro_od_truth_error.parquet"),
366 ExportCfg::default(),
367 )?;
368
369 Ok(())
370}pub fn latest() -> Result<Almanac, AlmanacError>
pub fn latest() -> Result<Almanac, AlmanacError>
Returns an Almanac loaded from the latest NAIF data via the default MetaAlmanac.
The MetaAlmanac will download the DE440s.bsp file, the PCK0008.PCA, the full Moon Principal Axis BPC (moon_pa_de440_200625) and the latest high precision Earth kernel from JPL.
§File list
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/de440s.bsp
- http://public-data.nyxspace.com/anise/v0.10/pck11.pca
- http://public-data.nyxspace.com/anise/v0.10/moon_fk_de440.epa
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/moon_pa_de440_200625.bpc
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/earth_latest_high_prec.bpc
§Reproducibility
Note that the earth_latest_high_prec.bpc file is updated daily (or so). As such,
if queried at some future time, the Earth rotation parameters may have changed between two queries.
Examples found in repository?
28fn main() -> Result<(), Box<dyn Error>> {
29 pel::init();
30 // Set up the dynamics like in the orbit raise.
31 let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
32 let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
33
34 // Define the GEO orbit, and we're just going to maintain it very tightly.
35 let earth_j2000 = almanac.frame_info(EARTH_J2000)?;
36 let orbit = Orbit::try_keplerian(42164.0, 1e-5, 0., 163.0, 75.0, 0.0, epoch, earth_j2000)?;
37 println!("{orbit:x}");
38
39 let sc = Spacecraft::builder()
40 .orbit(orbit)
41 .mass(Mass::from_dry_and_prop_masses(1000.0, 1000.0)) // 1000 kg of dry mass and prop, totalling 2.0 tons
42 .srp(SRPData::from_area(3.0 * 6.0)) // Assuming 1 kW/m^2 or 18 kW, giving a margin of 4.35 kW for on-propulsion consumption
43 .thruster(Thruster {
44 // "NEXT-STEP" row in Table 2
45 isp_s: 4435.0,
46 thrust_N: 0.472,
47 })
48 .mode(GuidanceMode::Thrust) // Start thrusting immediately.
49 .build();
50
51 // Set up the spacecraft dynamics like in the orbit raise example.
52
53 let prop_time = 30.0 * Unit::Day;
54
55 // Define the guidance law -- we're just using a Ruggiero controller as demonstrated in AAS-2004-5089.
56 let objectives = &[
57 Objective::within_tolerance(
58 StateParameter::Element(OrbitalElement::SemiMajorAxis),
59 42_165.0,
60 20.0,
61 ),
62 Objective::within_tolerance(
63 StateParameter::Element(OrbitalElement::Eccentricity),
64 0.001,
65 5e-5,
66 ),
67 Objective::within_tolerance(
68 StateParameter::Element(OrbitalElement::Inclination),
69 0.05,
70 1e-2,
71 ),
72 ];
73
74 let ruggiero_ctrl = Ruggiero::from_max_eclipse(objectives, sc, 0.2)?;
75 println!("{ruggiero_ctrl}");
76
77 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
78
79 let mut jgm3_meta = MetaFile {
80 uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
81 crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
82 };
83 jgm3_meta.process(true)?;
84
85 let harmonics = GravityField::new(GravityFieldData::from_cof(
86 &jgm3_meta.uri,
87 8,
88 8,
89 true,
90 almanac.frame_info(IAU_EARTH_FRAME)?,
91 )?);
92 orbital_dyn.accel_models.push(harmonics);
93
94 let srp_dyn = SolarPressure::default_flux(EARTH_J2000, &almanac)?;
95 let sc_dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn)
96 .with_guidance_law(ruggiero_ctrl.clone());
97
98 println!("{sc_dynamics}");
99
100 // Finally, let's use the Monte Carlo framework built into Nyx to propagate spacecraft.
101
102 // Let's start by defining the dispersion.
103 // The MultivariateNormal structure allows us to define the dispersions in any of the orbital parameters, but these are applied directly in the Cartesian state space.
104 // Note that additional validation on the MVN is in progress -- https://github.com/nyx-space/nyx/issues/339.
105 let mc_rv = MvnSpacecraft::new(
106 sc,
107 vec![StateDispersion::zero_mean(
108 StateParameter::Element(OrbitalElement::SemiMajorAxis),
109 3.0,
110 )],
111 )?;
112
113 let my_mc = MonteCarlo::new(
114 sc, // Nominal state
115 mc_rv,
116 "03_geo_sk".to_string(), // Scenario name
117 None, // No specific seed specified, so one will be drawn from the computer's entropy.
118 );
119
120 // Build the propagator setup.
121 let setup = Propagator::rk89(
122 sc_dynamics.clone(),
123 IntegratorOptions::builder()
124 .min_step(10.0_f64.seconds())
125 .error_ctrl(ErrorControl::RSSCartesianStep)
126 .build(),
127 );
128
129 let num_runs = 25;
130 let rslts = my_mc.run_until_epoch(setup, almanac.clone(), sc.epoch() + prop_time, num_runs);
131
132 assert_eq!(rslts.runs.len(), num_runs);
133
134 rslts.to_parquet("03_geo_sk.parquet", ExportCfg::default())?;
135
136 Ok(())
137}More examples
27fn main() -> Result<(), Box<dyn Error>> {
28 pel::init();
29
30 // Dynamics models require planetary constants and ephemerides to be defined.
31 // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
32 // This will automatically download the DE440s planetary ephemeris,
33 // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
34 // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
35 // planetary constants kernels.
36 // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
37 // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
38 // references to many functions.
39 let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
40 // Fetch the EME2000 frame from the Almabac
41 let eme2k = almanac.frame_info(EARTH_J2000).unwrap();
42 // Define the orbit epoch
43 let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
44
45 // Build the spacecraft itself.
46 // Using slide 6 of https://aerospace.org/sites/default/files/2018-11/Davis-Mayberry_HPSEP_11212018.pdf
47 // for the "next gen" SEP characteristics.
48
49 // GTO start
50 let orbit = Orbit::keplerian(24505.9, 0.725, 7.05, 0.0, 0.0, 0.0, epoch, eme2k);
51
52 let sc = Spacecraft::builder()
53 .orbit(orbit)
54 .mass(Mass::from_dry_and_prop_masses(1000.0, 1000.0)) // 1000 kg of dry mass and prop, totalling 2.0 tons
55 .srp(SRPData::from_area(3.0 * 6.0)) // Assuming 1 kW/m^2 or 18 kW, giving a margin of 4.35 kW for on-propulsion consumption
56 .thruster(Thruster {
57 // "NEXT-STEP" row in Table 2
58 isp_s: 4435.0,
59 thrust_N: 0.472,
60 })
61 .mode(GuidanceMode::Thrust) // Start thrusting immediately.
62 .build();
63
64 let prop_time = 180.0 * Unit::Day;
65
66 // Define the guidance law -- we're just using a Ruggiero controller as demonstrated in AAS-2004-5089.
67 let objectives = &[
68 Objective::within_tolerance(
69 StateParameter::Element(OrbitalElement::SemiMajorAxis),
70 42_165.0,
71 20.0,
72 ),
73 Objective::within_tolerance(
74 StateParameter::Element(OrbitalElement::Eccentricity),
75 0.001,
76 5e-5,
77 ),
78 Objective::within_tolerance(
79 StateParameter::Element(OrbitalElement::Inclination),
80 0.05,
81 1e-2,
82 ),
83 ];
84
85 // Ensure that we only thrust if we have more than 20% illumination.
86 let ruggiero_ctrl = Ruggiero::from_max_eclipse(objectives, sc, 0.2).unwrap();
87 println!("{ruggiero_ctrl}");
88
89 // Define the high fidelity dynamics
90
91 // Set up the spacecraft dynamics.
92
93 // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
94 // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
95 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
96
97 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
98 // We're using the JGM3 model here, which is the default in GMAT.
99 let mut jgm3_meta = MetaFile {
100 uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
101 crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
102 };
103 // And let's download it if we don't have it yet.
104 jgm3_meta.process(true)?;
105
106 // Build the spherical harmonics.
107 // The harmonics must be computed in the body fixed frame.
108 // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
109 let harmonics = GravityField::new(
110 GravityFieldData::from_cof(
111 &jgm3_meta.uri,
112 8,
113 8,
114 true,
115 almanac.frame_info(IAU_EARTH_FRAME)?,
116 )
117 .unwrap(),
118 );
119
120 // Include the spherical harmonics into the orbital dynamics.
121 orbital_dyn.accel_models.push(harmonics);
122
123 // We define the solar radiation pressure, using the default solar flux and accounting only
124 // for the eclipsing caused by the Earth.
125 let srp_dyn = SolarPressure::default_flux(EARTH_J2000, &almanac)?;
126
127 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
128 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
129 let sc_dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn)
130 .with_guidance_law(ruggiero_ctrl.clone());
131
132 println!("{orbit:x}");
133
134 // We specify a minimum step in the propagator because the Ruggiero control would otherwise drive this step very low.
135 let (final_state, traj) = Propagator::rk89(
136 sc_dynamics.clone(),
137 IntegratorOptions::builder()
138 .min_step(10.0_f64.seconds())
139 .error_ctrl(ErrorControl::RSSCartesianStep)
140 .build(),
141 )
142 .with(sc, almanac.clone())
143 .for_duration_with_traj(prop_time)?;
144
145 let prop_usage = sc.mass.prop_mass_kg - final_state.mass.prop_mass_kg;
146 println!("{:x}", final_state.orbit);
147 println!("prop usage: {prop_usage:.3} kg");
148
149 // Finally, export the results for analysis, including the penumbra percentage throughout the orbit raise.
150 traj.to_parquet("./03_geo_raise.parquet", ExportCfg::default())?;
151
152 for status_line in ruggiero_ctrl.status(&final_state) {
153 println!("{status_line}");
154 }
155
156 ruggiero_ctrl
157 .achieved(&final_state)
158 .expect("objective not achieved");
159
160 Ok(())
161}26fn main() -> Result<(), Box<dyn Error>> {
27 pel::init();
28 // Dynamics models require planetary constants and ephemerides to be defined.
29 // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
30 // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
31
32 // Download the regularly update of the James Webb Space Telescope reconstucted (or definitive) ephemeris.
33 // Refer to https://naif.jpl.nasa.gov/pub/naif/JWST/kernels/spk/aareadme.txt for details.
34 let mut latest_jwst_ephem = MetaFile {
35 uri: "https://naif.jpl.nasa.gov/pub/naif/JWST/kernels/spk/jwst_rec.bsp".to_string(),
36 crc32: None,
37 };
38 latest_jwst_ephem.process(true)?;
39
40 // Load this ephem in the general Almanac we're using for this analysis.
41 let almanac = Arc::new(
42 MetaAlmanac::latest()
43 .map_err(Box::new)?
44 .load_from_metafile(latest_jwst_ephem, true)?,
45 );
46
47 // By loading this ephemeris file in the ANISE GUI or ANISE CLI, we can find the NAIF ID of the JWST
48 // in the BSP. We need this ID in order to query the ephemeris.
49 const JWST_NAIF_ID: i32 = -170;
50 // Let's build a frame in the J2000 orientation centered on the JWST.
51 const JWST_J2000: Frame = Frame::from_ephem_j2000(JWST_NAIF_ID);
52
53 // Since the ephemeris file is updated regularly, we'll just grab the latest state in the ephem.
54 let (earliest_epoch, latest_epoch) = almanac.spk_domain(JWST_NAIF_ID)?;
55 println!("JWST defined from {earliest_epoch} to {latest_epoch}");
56 // Fetch the state, printing it in the Earth J2000 frame.
57 let jwst_orbit = almanac.transform(JWST_J2000, EARTH_J2000, latest_epoch, None)?;
58 println!("{jwst_orbit:x}");
59
60 // Build the spacecraft
61 // SRP area assumed to be the full sunshield and mass if 6200.0 kg, c.f. https://webb.nasa.gov/content/about/faqs/facts.html
62 // SRP Coefficient of reflectivity assumed to be that of Kapton, i.e. 2 - 0.44 = 1.56, table 1 from https://amostech.com/TechnicalPapers/2018/Poster/Bengtson.pdf
63 let jwst = Spacecraft::builder()
64 .orbit(jwst_orbit)
65 .srp(SRPData {
66 area_m2: 21.197 * 14.162,
67 coeff_reflectivity: 1.56,
68 })
69 .mass(Mass::from_dry_mass(6200.0))
70 .build();
71
72 // Build up the spacecraft uncertainty builder.
73 // We can use the spacecraft uncertainty structure to build this up.
74 // We start by specifying the nominal state (as defined above), then the uncertainty in position and velocity
75 // in the RIC frame. We could also specify the Cr, Cd, and mass uncertainties, but these aren't accounted for until
76 // Nyx can also estimate the deviation of the spacecraft parameters.
77 let jwst_uncertainty = SpacecraftUncertainty::builder()
78 .nominal(jwst)
79 .frame(LocalFrame::RIC)
80 .x_km(0.5)
81 .y_km(0.3)
82 .z_km(1.5)
83 .vx_km_s(1e-4)
84 .vy_km_s(0.6e-3)
85 .vz_km_s(3e-3)
86 .build();
87
88 println!("{jwst_uncertainty}");
89
90 // Build the Kalman filter estimate.
91 // Note that we could have used the KfEstimate structure directly (as seen throughout the OD integration tests)
92 // but this approach requires quite a bit more boilerplate code.
93 let jwst_estimate = jwst_uncertainty.to_estimate()?;
94
95 // Set up the spacecraft dynamics.
96 // We'll use the point masses of the Earth, Sun, Jupiter (barycenter, because it's in the DE440), and the Moon.
97 // We'll also enable solar radiation pressure since the James Webb has a huge and highly reflective sun shield.
98
99 let orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN, JUPITER_BARYCENTER]);
100 let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], &almanac)?;
101
102 // Finalize setting up the dynamics.
103 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
104
105 // Build the propagator set up to use for the whole analysis.
106 let setup = Propagator::default(dynamics);
107
108 // All of the analysis will use this duration.
109 let prediction_duration = 6.5 * Unit::Day;
110
111 // === Covariance mapping ===
112 // For the covariance mapping / prediction, we'll use the common orbit determination approach.
113 // This is done by setting up a spacecraft Kalman filter OD process, and predicting for the analysis duration.
114
115 // Build the propagation instance for the OD process.
116 let odp = SpacecraftKalmanOD::new(
117 setup.clone(),
118 KalmanVariant::DeviationTracking,
119 None,
120 BTreeMap::new(),
121 almanac.clone(),
122 );
123
124 // The prediction step is 1 minute by default, configured in the OD process, i.e. how often we want to know the covariance.
125 assert_eq!(odp.max_step, 1_i64.minutes());
126 // Finally, predict, and export the trajectory with covariance to a parquet file.
127 let od_sol = odp.predict_for(jwst_estimate, prediction_duration)?;
128 od_sol.to_parquet("./02_jwst_covar_map.parquet", ExportCfg::default())?;
129
130 // === Monte Carlo framework ===
131 // Nyx comes with a complete multi-threaded Monte Carlo frame. It's blazing fast.
132
133 let my_mc = MonteCarlo::new(
134 jwst, // Nominal state
135 jwst_estimate.to_random_variable()?,
136 "02_jwst".to_string(), // Scenario name
137 None, // No specific seed specified, so one will be drawn from the computer's entropy.
138 );
139
140 let num_runs = 5_000;
141 let rslts = my_mc.run_until_epoch(
142 setup,
143 almanac.clone(),
144 jwst.epoch() + prediction_duration,
145 num_runs,
146 );
147
148 assert_eq!(rslts.runs.len(), num_runs);
149 // Finally, export these results, computing the eclipse percentage for all of these results.
150
151 rslts.to_parquet("02_jwst_monte_carlo.parquet", ExportCfg::default())?;
152
153 Ok(())
154}26fn main() -> Result<(), Box<dyn Error>> {
27 pel::init();
28 // Dynamics models require planetary constants and ephemerides to be defined.
29 // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
30 // This will automatically download the DE440s planetary ephemeris,
31 // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
32 // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
33 // planetary constants kernels.
34 // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
35 // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
36 // references to many functions.
37 let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
38 // Define the orbit epoch
39 let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
40
41 // Define the orbit.
42 // First we need to fetch the Earth J2000 from information from the Almanac.
43 // This allows the frame to include the gravitational parameters and the shape of the Earth,
44 // defined as a tri-axial ellipoid. Note that this shape can be changed manually or in the Almanac
45 // by loading a different set of planetary constants.
46 let earth_j2000 = almanac.frame_info(EARTH_J2000)?;
47
48 // Placing this GEO bird just above Colorado.
49 // In theory, the eccentricity is zero, but in practice, it's about 1e-5 to 1e-6 at best.
50 let orbit = Orbit::try_keplerian(42164.0, 1e-5, 0., 163.0, 75.0, 0.0, epoch, earth_j2000)?;
51 // Print in in Keplerian form.
52 println!("{orbit:x}");
53
54 let state_bf = almanac.transform_to(orbit, IAU_EARTH_FRAME, None)?;
55 let (orig_lat_deg, orig_long_deg, orig_alt_km) = state_bf.latlongalt()?;
56
57 // Nyx is used for high fidelity propagation, not Keplerian propagation as above.
58 // Nyx only propagates Spacecraft at the moment, which allows it to account for acceleration
59 // models such as solar radiation pressure.
60
61 // Let's build a cubesat sized spacecraft, with an SRP area of 10 cm^2 and a mass of 9.6 kg.
62 let sc = Spacecraft::builder()
63 .orbit(orbit)
64 .mass(Mass::from_dry_mass(9.60))
65 .srp(SRPData {
66 area_m2: 10e-4,
67 coeff_reflectivity: 1.1,
68 })
69 .build();
70 println!("{sc:x}");
71
72 // Set up the spacecraft dynamics.
73
74 // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
75 // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
76 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
77
78 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
79 // We're using the JGM3 model here, which is the default in GMAT.
80 let mut jgm3_meta = MetaFile {
81 uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
82 crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
83 };
84 // And let's download it if we don't have it yet.
85 jgm3_meta.process(true)?;
86
87 // Build the spherical harmonics.
88 // The harmonics must be computed in the body fixed frame.
89 // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
90 let harmonics_21x21 = GravityField::new(
91 GravityFieldData::from_cof(
92 &jgm3_meta.uri,
93 21,
94 21,
95 true,
96 almanac.frame_info(IAU_EARTH_FRAME)?,
97 )
98 .unwrap(),
99 );
100
101 // Include the spherical harmonics into the orbital dynamics.
102 orbital_dyn.accel_models.push(harmonics_21x21);
103
104 // We define the solar radiation pressure, using the default solar flux and accounting only
105 // for the eclipsing caused by the Earth and Moon.
106 let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], &almanac)?;
107
108 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
109 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
110 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
111
112 println!("{dynamics}");
113
114 // Finally, let's propagate this orbit to the same epoch as above.
115 // The first returned value is the spacecraft state at the final epoch.
116 // The second value is the full trajectory where the step size is variable step used by the propagator.
117 let (future_sc, trajectory) = Propagator::default(dynamics)
118 .with(sc, almanac.clone())
119 .until_epoch_with_traj(epoch + Unit::Century * 0.03)?;
120
121 println!("=== High fidelity propagation ===");
122 println!(
123 "SMA changed by {:.3} km",
124 orbit.sma_km()? - future_sc.orbit.sma_km()?
125 );
126 println!(
127 "ECC changed by {:.6}",
128 orbit.ecc()? - future_sc.orbit.ecc()?
129 );
130 println!(
131 "INC changed by {:.3e} deg",
132 orbit.inc_deg()? - future_sc.orbit.inc_deg()?
133 );
134 println!(
135 "RAAN changed by {:.3} deg",
136 orbit.raan_deg()? - future_sc.orbit.raan_deg()?
137 );
138 println!(
139 "AOP changed by {:.3} deg",
140 orbit.aop_deg()? - future_sc.orbit.aop_deg()?
141 );
142 println!(
143 "TA changed by {:.3} deg",
144 orbit.ta_deg()? - future_sc.orbit.ta_deg()?
145 );
146
147 // We also have access to the full trajectory throughout the propagation.
148 println!("{trajectory}");
149
150 println!("Spacecraft params after 3 years without active control:\n{future_sc:x}");
151
152 // With the trajectory, let's build a few data products.
153
154 // 1. Export the trajectory as a parquet file, which includes the Keplerian orbital elements.
155
156 let analysis_step = Unit::Minute * 5;
157
158 trajectory.to_parquet(
159 "./03_geo_hf_prop.parquet",
160 ExportCfg::builder().step(analysis_step).build(),
161 )?;
162
163 // 2. Compute the latitude, longitude, and altitude throughout the trajectory by rotating the spacecraft position into the Earth body fixed frame.
164
165 // We iterate over the trajectory, grabbing a state every two minutes.
166 let mut offset_s = vec![];
167 let mut epoch_str = vec![];
168 let mut longitude_deg = vec![];
169 let mut latitude_deg = vec![];
170 let mut altitude_km = vec![];
171
172 for state in trajectory.every(analysis_step) {
173 // Convert the GEO bird state into the body fixed frame, and keep track of its latitude, longitude, and altitude.
174 // These define the GEO stationkeeping box.
175
176 let this_epoch = state.epoch();
177
178 offset_s.push((this_epoch - orbit.epoch).to_seconds());
179 epoch_str.push(this_epoch.to_isoformat());
180
181 let state_bf = almanac.transform_to(state.orbit, IAU_EARTH_FRAME, None)?;
182 let (lat_deg, long_deg, alt_km) = state_bf.latlongalt()?;
183 longitude_deg.push(long_deg);
184 latitude_deg.push(lat_deg);
185 altitude_km.push(alt_km);
186 }
187
188 println!(
189 "Longitude changed by {:.3} deg -- Box is 0.1 deg E-W",
190 orig_long_deg - longitude_deg.last().unwrap()
191 );
192
193 println!(
194 "Latitude changed by {:.3} deg -- Box is 0.05 deg N-S",
195 orig_lat_deg - latitude_deg.last().unwrap()
196 );
197
198 println!(
199 "Altitude changed by {:.3} km -- Box is 30 km",
200 orig_alt_km - altitude_km.last().unwrap()
201 );
202
203 // Build the station keeping data frame.
204 let mut sk_df = df!(
205 "Offset (s)" => offset_s.clone(),
206 "Epoch (UTC)" => epoch_str.clone(),
207 "Longitude E-W (deg)" => longitude_deg,
208 "Latitude N-S (deg)" => latitude_deg,
209 "Altitude (km)" => altitude_km,
210
211 )?;
212
213 // Create a file to write the Parquet to
214 let file = File::create("./03_geo_lla.parquet").expect("Could not create file");
215
216 // Create a ParquetWriter and write the DataFrame to the file
217 ParquetWriter::new(file).finish(&mut sk_df)?;
218
219 Ok(())
220}30fn main() -> Result<(), Box<dyn Error>> {
31 pel::init();
32 // Dynamics models require planetary constants and ephemerides to be defined.
33 // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
34 // This will automatically download the DE440s planetary ephemeris,
35 // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
36 // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
37 // planetary constants kernels.
38 // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
39 // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
40 // references to many functions.
41 let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
42 // Define the orbit epoch
43 let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
44
45 // Define the orbit.
46 // First we need to fetch the Earth J2000 from information from the Almanac.
47 // This allows the frame to include the gravitational parameters and the shape of the Earth,
48 // defined as a tri-axial ellipoid. Note that this shape can be changed manually or in the Almanac
49 // by loading a different set of planetary constants.
50 let earth_j2000 = almanac.frame_info(EARTH_J2000)?;
51
52 let orbit =
53 Orbit::try_keplerian_altitude(300.0, 0.015, 68.5, 65.2, 75.0, 0.0, epoch, earth_j2000)?;
54 // Print in in Keplerian form.
55 println!("{orbit:x}");
56
57 // There are two ways to propagate an orbit. We can make a quick approximation assuming only two-body
58 // motion. This is a useful first order approximation but it isn't used in real-world applications.
59
60 // This approach is a feature of ANISE.
61 let future_orbit_tb = orbit.at_epoch(epoch + Unit::Day * 3)?;
62 println!("{future_orbit_tb:x}");
63
64 // Two body propagation relies solely on Kepler's laws, so only the true anomaly will change.
65 println!(
66 "SMA changed by {:.3e} km",
67 orbit.sma_km()? - future_orbit_tb.sma_km()?
68 );
69 println!(
70 "ECC changed by {:.3e}",
71 orbit.ecc()? - future_orbit_tb.ecc()?
72 );
73 println!(
74 "INC changed by {:.3e} deg",
75 orbit.inc_deg()? - future_orbit_tb.inc_deg()?
76 );
77 println!(
78 "RAAN changed by {:.3e} deg",
79 orbit.raan_deg()? - future_orbit_tb.raan_deg()?
80 );
81 println!(
82 "AOP changed by {:.3e} deg",
83 orbit.aop_deg()? - future_orbit_tb.aop_deg()?
84 );
85 println!(
86 "TA changed by {:.3} deg",
87 orbit.ta_deg()? - future_orbit_tb.ta_deg()?
88 );
89
90 // Nyx is used for high fidelity propagation, not Keplerian propagation as above.
91 // Nyx only propagates Spacecraft at the moment, which allows it to account for acceleration
92 // models such as solar radiation pressure.
93
94 // Let's build a cubesat sized spacecraft, with an SRP area of 10 cm^2 and a mass of 9.6 kg.
95 let sc = Spacecraft::builder()
96 .orbit(orbit)
97 .mass(Mass::from_dry_mass(9.60))
98 .srp(SRPData {
99 area_m2: 10e-4,
100 coeff_reflectivity: 1.1,
101 })
102 .build();
103 println!("{sc:x}");
104
105 // Set up the spacecraft dynamics.
106
107 // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
108 // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
109 let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
110
111 // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
112 // We're using the JGM3 model here, which is the default in GMAT.
113 let mut jgm3_meta = MetaFile {
114 uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
115 crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
116 };
117 // And let's download it if we don't have it yet.
118 jgm3_meta.process(true)?;
119
120 // Build the spherical harmonics.
121 // The harmonics must be computed in the body fixed frame.
122 // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
123 let harmonics_21x21 = GravityField::new(
124 GravityFieldData::from_cof(
125 &jgm3_meta.uri,
126 21,
127 21,
128 true,
129 almanac.frame_info(IAU_EARTH_FRAME)?,
130 )
131 .unwrap(),
132 );
133
134 // Include the spherical harmonics into the orbital dynamics.
135 orbital_dyn.accel_models.push(harmonics_21x21);
136
137 // We define the solar radiation pressure, using the default solar flux and accounting only
138 // for the eclipsing caused by the Earth.
139 let srp_dyn = SolarPressure::default_flux(EARTH_J2000, &almanac)?;
140
141 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
142 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
143 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
144
145 println!("{dynamics}");
146
147 // Finally, let's propagate this orbit to the same epoch as above.
148 // The first returned value is the spacecraft state at the final epoch.
149 // The second value is the full trajectory where the step size is variable step used by the propagator.
150 let (future_sc, trajectory) = Propagator::default(dynamics)
151 .with(sc, almanac.clone())
152 .until_epoch_with_traj(future_orbit_tb.epoch)?;
153
154 println!("=== High fidelity propagation ===");
155 println!(
156 "SMA changed by {:.3} km",
157 orbit.sma_km()? - future_sc.orbit.sma_km()?
158 );
159 println!(
160 "ECC changed by {:.6}",
161 orbit.ecc()? - future_sc.orbit.ecc()?
162 );
163 println!(
164 "INC changed by {:.3e} deg",
165 orbit.inc_deg()? - future_sc.orbit.inc_deg()?
166 );
167 println!(
168 "RAAN changed by {:.3} deg",
169 orbit.raan_deg()? - future_sc.orbit.raan_deg()?
170 );
171 println!(
172 "AOP changed by {:.3} deg",
173 orbit.aop_deg()? - future_sc.orbit.aop_deg()?
174 );
175 println!(
176 "TA changed by {:.3} deg",
177 orbit.ta_deg()? - future_sc.orbit.ta_deg()?
178 );
179
180 // We also have access to the full trajectory throughout the propagation.
181 println!("{trajectory}");
182
183 // With the trajectory, let's build a few data products.
184
185 // 1. Export the trajectory as a CCSDS OEM version 2.0 file and as a parquet file, which includes the Keplerian orbital elements.
186
187 trajectory.to_oem_file(
188 "./01_cubesat_hf_prop.oem",
189 "CUBESAT-ID".to_string(),
190 Some("Nyx Space".to_string()),
191 Some("CUBESAT".to_string()),
192 ExportCfg::builder().step(Unit::Minute * 2).build(),
193 )?;
194
195 trajectory.to_parquet_with_cfg(
196 "./01_cubesat_hf_prop.parquet",
197 ExportCfg::builder().step(Unit::Minute * 2).build(),
198 )?;
199
200 // 2. Compare the difference in the radial-intrack-crosstrack frame between the high fidelity
201 // and Keplerian propagation. The RIC frame is commonly used to compute the difference in position
202 // and velocity of different spacecraft.
203 // 3. Compute the azimuth, elevation, range, and range-rate data of that spacecraft as seen from Boulder, CO, USA.
204
205 let boulder_station = GroundStation::from_point(
206 "Boulder, CO, USA".to_string(),
207 40.014984, // latitude in degrees
208 -105.270546, // longitude in degrees
209 1.6550, // altitude in kilometers
210 almanac.frame_info(IAU_EARTH_FRAME)?,
211 );
212
213 // We iterate over the trajectory, grabbing a state every two minutes.
214 let mut offset_s = vec![];
215 let mut epoch_str = vec![];
216 let mut ric_x_km = vec![];
217 let mut ric_y_km = vec![];
218 let mut ric_z_km = vec![];
219 let mut ric_vx_km_s = vec![];
220 let mut ric_vy_km_s = vec![];
221 let mut ric_vz_km_s = vec![];
222
223 let mut azimuth_deg = vec![];
224 let mut elevation_deg = vec![];
225 let mut range_km = vec![];
226 let mut range_rate_km_s = vec![];
227 for state in trajectory.every(Unit::Minute * 2) {
228 // Try to compute the Keplerian/two body state just in time.
229 // This method occasionally fails to converge on an appropriate true anomaly
230 // from the mean anomaly. If that happens, we just skip this state.
231 // The high fidelity and Keplerian states diverge continuously, and we're curious
232 // about the divergence in this quick analysis.
233 let this_epoch = state.epoch();
234 match orbit.at_epoch(this_epoch) {
235 Ok(tb_then) => {
236 offset_s.push((this_epoch - orbit.epoch).to_seconds());
237 epoch_str.push(format!("{this_epoch}"));
238 // Compute the two body state just in time.
239 let ric = state.orbit.ric_difference(&tb_then)?;
240 ric_x_km.push(ric.radius_km.x);
241 ric_y_km.push(ric.radius_km.y);
242 ric_z_km.push(ric.radius_km.z);
243 ric_vx_km_s.push(ric.velocity_km_s.x);
244 ric_vy_km_s.push(ric.velocity_km_s.y);
245 ric_vz_km_s.push(ric.velocity_km_s.z);
246
247 // Compute the AER data for each state.
248 let aer = almanac.azimuth_elevation_range_sez(
249 state.orbit,
250 boulder_station.to_orbit(this_epoch, &almanac)?,
251 None,
252 None,
253 )?;
254 azimuth_deg.push(aer.azimuth_deg);
255 elevation_deg.push(aer.elevation_deg);
256 range_km.push(aer.range_km);
257 range_rate_km_s.push(aer.range_rate_km_s);
258 }
259 Err(e) => warn!("{} {e}", state.epoch()),
260 };
261 }
262
263 // Build the data frames.
264 let ric_df = df!(
265 "Offset (s)" => offset_s.clone(),
266 "Epoch" => epoch_str.clone(),
267 "RIC X (km)" => ric_x_km,
268 "RIC Y (km)" => ric_y_km,
269 "RIC Z (km)" => ric_z_km,
270 "RIC VX (km/s)" => ric_vx_km_s,
271 "RIC VY (km/s)" => ric_vy_km_s,
272 "RIC VZ (km/s)" => ric_vz_km_s,
273 )?;
274
275 println!("RIC difference at start\n{}", ric_df.head(Some(10)));
276 println!("RIC difference at end\n{}", ric_df.tail(Some(10)));
277
278 let aer_df = df!(
279 "Offset (s)" => offset_s.clone(),
280 "Epoch" => epoch_str.clone(),
281 "azimuth (deg)" => azimuth_deg,
282 "elevation (deg)" => elevation_deg,
283 "range (km)" => range_km,
284 "range rate (km/s)" => range_rate_km_s,
285 )?;
286
287 // Finally, let's see when the spacecraft is visible, assuming 15 degrees minimum elevation.
288 let mask = aer_df
289 .column("elevation (deg)")?
290 .gt(&Column::Scalar(ScalarColumn::new(
291 "elevation mask (deg)".into(),
292 Scalar::new(DataType::Float64, AnyValue::Float64(15.0)),
293 offset_s.len(),
294 )))?;
295 let cubesat_visible = aer_df.filter(&mask)?;
296
297 println!("{cubesat_visible}");
298
299 Ok(())
300}pub fn from_dhall(repr: &str) -> Result<MetaAlmanac, MetaAlmanacError>
pub fn from_dhall(repr: &str) -> Result<MetaAlmanac, MetaAlmanacError>
Loads this Meta Almanac from its Dhall string representation
§impl MetaAlmanac
impl MetaAlmanac
§impl MetaAlmanac
impl MetaAlmanac
pub fn py_new(
maybe_path: Option<String>,
) -> Result<MetaAlmanac, MetaAlmanacError>
pub fn py_new( maybe_path: Option<String>, ) -> Result<MetaAlmanac, MetaAlmanacError>
Loads the provided path as a Dhall file. If no path is provided, creates an empty MetaAlmanac that can store MetaFiles.
pub fn py_process(
&mut self,
py: Python<'_>,
autodelete: Option<bool>,
) -> Result<Almanac, AlmanacError>
pub fn py_process( &mut self, py: Python<'_>, autodelete: Option<bool>, ) -> Result<Almanac, AlmanacError>
Fetch all of the URIs and return a loaded Almanac.
When downloading the data, ANISE will create a temporarily lock file to prevent race conditions
where multiple processes download the data at the same time. Set autodelete to true to delete
this lock file if a dead lock is detected after 10 seconds. Set this flag to false if you have
more than ten processes which may attempt to download files in parallel.
:type autodelete: bool, optional :rtype: Almanac
Trait Implementations§
§impl Clone for MetaAlmanac
impl Clone for MetaAlmanac
§fn clone(&self) -> MetaAlmanac
fn clone(&self) -> MetaAlmanac
1.0.0 (const: unstable) · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read more§impl Debug for MetaAlmanac
impl Debug for MetaAlmanac
§impl Default for MetaAlmanac
By default, the MetaAlmanac will download the DE440s.bsp file, the PCK0008.PCA, the full Moon Principal Axis BPC (moon_pa_de440_200625) and the latest high precision Earth kernel from JPL.
impl Default for MetaAlmanac
By default, the MetaAlmanac will download the DE440s.bsp file, the PCK0008.PCA, the full Moon Principal Axis BPC (moon_pa_de440_200625) and the latest high precision Earth kernel from JPL.
§File list
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/de440s.bsp
- http://public-data.nyxspace.com/anise/v0.10/pck11.pca
- http://public-data.nyxspace.com/anise/v0.10/moon_fk_de440.epa
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/moon_pa_de440_200625.bpc
- https://naif.jpl.nasa.gov/pub/naif/generic_kernels/pck/earth_latest_high_prec.bpc
§Reproducibility
Note that the earth_latest_high_prec.bpc file is updated daily (or so). As such,
if queried at some future time, the Earth rotation parameters may have changed between two queries.
§fn default() -> MetaAlmanac
fn default() -> MetaAlmanac
impl DerefToPyAny for MetaAlmanac
§impl<'de> Deserialize<'de> for MetaAlmanac
impl<'de> Deserialize<'de> for MetaAlmanac
§fn deserialize<__D>(
__deserializer: __D,
) -> Result<MetaAlmanac, <__D as Deserializer<'de>>::Error>where
__D: Deserializer<'de>,
fn deserialize<__D>(
__deserializer: __D,
) -> Result<MetaAlmanac, <__D as Deserializer<'de>>::Error>where
__D: Deserializer<'de>,
§impl<'a, 'py> FromPyObject<'a, 'py> for MetaAlmanacwhere
MetaAlmanac: Clone,
impl<'a, 'py> FromPyObject<'a, 'py> for MetaAlmanacwhere
MetaAlmanac: Clone,
§type Error = PyClassGuardError<'a, 'py>
type Error = PyClassGuardError<'a, 'py>
§fn extract(
obj: Borrowed<'a, 'py, PyAny>,
) -> Result<MetaAlmanac, <MetaAlmanac as FromPyObject<'a, 'py>>::Error>
fn extract( obj: Borrowed<'a, 'py, PyAny>, ) -> Result<MetaAlmanac, <MetaAlmanac as FromPyObject<'a, 'py>>::Error>
§impl FromStr for MetaAlmanac
impl FromStr for MetaAlmanac
§impl<'py> IntoPyObject<'py> for MetaAlmanac
impl<'py> IntoPyObject<'py> for MetaAlmanac
§type Target = MetaAlmanac
type Target = MetaAlmanac
§type Output = Bound<'py, <MetaAlmanac as IntoPyObject<'py>>::Target>
type Output = Bound<'py, <MetaAlmanac as IntoPyObject<'py>>::Target>
§fn into_pyobject(
self,
py: Python<'py>,
) -> Result<<MetaAlmanac as IntoPyObject<'py>>::Output, <MetaAlmanac as IntoPyObject<'py>>::Error>
fn into_pyobject( self, py: Python<'py>, ) -> Result<<MetaAlmanac as IntoPyObject<'py>>::Output, <MetaAlmanac as IntoPyObject<'py>>::Error>
§impl PartialEq for MetaAlmanac
impl PartialEq for MetaAlmanac
§impl PyClass for MetaAlmanac
impl PyClass for MetaAlmanac
§impl PyTypeInfo for MetaAlmanac
impl PyTypeInfo for MetaAlmanac
§const NAME: &'static str = <Self as ::pyo3::PyClass>::NAME
const NAME: &'static str = <Self as ::pyo3::PyClass>::NAME
prefer using ::type_object(py).name() to get the correct runtime value
§const MODULE: Option<&'static str> = <Self as ::pyo3::impl_::pyclass::PyClassImpl>::MODULE
const MODULE: Option<&'static str> = <Self as ::pyo3::impl_::pyclass::PyClassImpl>::MODULE
prefer using ::type_object(py).module() to get the correct runtime value
§fn type_object_raw(py: Python<'_>) -> *mut PyTypeObject
fn type_object_raw(py: Python<'_>) -> *mut PyTypeObject
§fn type_object(py: Python<'_>) -> Bound<'_, PyType>
fn type_object(py: Python<'_>) -> Bound<'_, PyType>
§fn is_type_of(object: &Bound<'_, PyAny>) -> bool
fn is_type_of(object: &Bound<'_, PyAny>) -> bool
object is an instance of this type or a subclass of this type.§fn is_exact_type_of(object: &Bound<'_, PyAny>) -> bool
fn is_exact_type_of(object: &Bound<'_, PyAny>) -> bool
object is an instance of this type.§impl Serialize for MetaAlmanac
impl Serialize for MetaAlmanac
§fn serialize<__S>(
&self,
__serializer: __S,
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>where
__S: Serializer,
fn serialize<__S>(
&self,
__serializer: __S,
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>where
__S: Serializer,
§impl StaticType for MetaAlmanacwhere
Vec<MetaFile>: StaticType,
impl StaticType for MetaAlmanacwhere
Vec<MetaFile>: StaticType,
§fn static_type() -> SimpleType
fn static_type() -> SimpleType
impl StructuralPartialEq for MetaAlmanac
Auto Trait Implementations§
impl Freeze for MetaAlmanac
impl RefUnwindSafe for MetaAlmanac
impl Send for MetaAlmanac
impl Sync for MetaAlmanac
impl Unpin for MetaAlmanac
impl UnsafeUnpin for MetaAlmanac
impl UnwindSafe for MetaAlmanac
Blanket Implementations§
impl<T> Allocation for T
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
impl<ST, DT> CastableFrom<ST, Initialized, Initialized> for DT
impl<ST, DT> CastableFrom<ST, Uninit, Uninit> for DT
Source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> DeserializeOwned for Twhere
T: for<'de> Deserialize<'de>,
Source§impl<T> FromDhall for Twhere
T: DeserializeOwned,
impl<T> FromDhall for Twhere
T: DeserializeOwned,
fn from_dhall(v: &Value) -> Result<T, Error>
impl<'py, T> FromPyObjectOwned<'py> for Twhere
T: for<'a> FromPyObject<'a, 'py>,
§impl<T> Instrument for T
impl<T> Instrument for T
§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read more§impl<'py, T> IntoPyObjectExt<'py> for Twhere
T: IntoPyObject<'py>,
impl<'py, T> IntoPyObjectExt<'py> for Twhere
T: IntoPyObject<'py>,
§fn into_bound_py_any(self, py: Python<'py>) -> Result<Bound<'py, PyAny>, PyErr>
fn into_bound_py_any(self, py: Python<'py>) -> Result<Bound<'py, PyAny>, PyErr>
self into an owned Python object, dropping type information.§fn into_py_any(self, py: Python<'py>) -> Result<Py<PyAny>, PyErr>
fn into_py_any(self, py: Python<'py>) -> Result<Py<PyAny>, PyErr>
self into an owned Python object, dropping type information and unbinding it
from the 'py lifetime.§fn into_pyobject_or_pyerr(self, py: Python<'py>) -> Result<Self::Output, PyErr>
fn into_pyobject_or_pyerr(self, py: Python<'py>) -> Result<Self::Output, PyErr>
self into a Python object. Read more§impl<T> Pointable for T
impl<T> Pointable for T
§impl<T> PyErrArguments for T
impl<T> PyErrArguments for T
§impl<T> PyTypeCheck for Twhere
T: PyTypeInfo,
impl<T> PyTypeCheck for Twhere
T: PyTypeInfo,
§const NAME: &'static str = T::NAME
const NAME: &'static str = T::NAME
Use ::classinfo_object() instead and format the type name at runtime. Note that using built-in cast features is often better than manual PyTypeCheck usage.
§fn type_check(object: &Bound<'_, PyAny>) -> bool
fn type_check(object: &Bound<'_, PyAny>) -> bool
§fn classinfo_object(py: Python<'_>) -> Bound<'_, PyAny>
fn classinfo_object(py: Python<'_>) -> Bound<'_, PyAny>
isinstance and issubclass function. Read moreimpl<T> Read<Exclusive, BecauseExclusive> for Twhere
T: ?Sized,
impl<T> Scalar for T
impl<T> Scalar for T
§impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
§fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
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superset. Read more§fn is_in_subset(&self) -> bool
fn is_in_subset(&self) -> bool
self is actually part of its subset T (and can be converted to it).§fn to_subset_unchecked(&self) -> SS
fn to_subset_unchecked(&self) -> SS
self.to_subset but without any property checks. Always succeeds.§fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
self to the equivalent element of its superset.§impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
§fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
self from the equivalent element of its
superset. Read more§fn is_in_subset(&self) -> bool
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fn to_subset_unchecked(&self) -> SS
self.to_subset but without any property checks. Always succeeds.§fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
self to the equivalent element of its superset.