pub struct ExportCfg {
pub fields: Option<Vec<StateParameter>>,
pub start_epoch: Option<Epoch>,
pub end_epoch: Option<Epoch>,
pub step: Option<Duration>,
pub metadata: Option<HashMap<String, String>>,
pub timestamp: bool,
}Expand description
Configuration for exporting a trajectory to parquet.
Fields§
§fields: Option<Vec<StateParameter>>Fields to export, if unset, defaults to all possible fields.
start_epoch: Option<Epoch>Start epoch to export, defaults to the start of the trajectory
end_epoch: Option<Epoch>End epoch to export, defaults to the end of the trajectory
step: Option<Duration>An optional step, defaults to every state in the trajectory (which likely isn’t equidistant)
metadata: Option<HashMap<String, String>>Additional metadata to store in the Parquet metadata
timestamp: boolSet to true to append the timestamp to the filename
Implementations§
Source§impl ExportCfg
impl ExportCfg
Sourcepub fn builder() -> ExportCfgBuilder<((), (), (), (), (), ())>
pub fn builder() -> ExportCfgBuilder<((), (), (), (), (), ())>
Create a builder for building ExportCfg.
On the builder, call .fields(...)(optional), .start_epoch(...)(optional), .end_epoch(...)(optional), .step(...)(optional), .metadata(...)(optional), .timestamp(...)(optional) to set the values of the fields.
Finally, call .build() to create the instance of ExportCfg.
Examples found in repository?
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 = Harmonics::from_stor(
91 almanac.frame_info(IAU_EARTH_FRAME)?,
92 HarmonicsMem::from_cof(&jgm3_meta.uri, 21, 21, true).unwrap(),
93 );
94
95 // Include the spherical harmonics into the orbital dynamics.
96 orbital_dyn.accel_models.push(harmonics_21x21);
97
98 // We define the solar radiation pressure, using the default solar flux and accounting only
99 // for the eclipsing caused by the Earth and Moon.
100 let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], almanac.clone())?;
101
102 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
103 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
104 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
105
106 println!("{dynamics}");
107
108 // Finally, let's propagate this orbit to the same epoch as above.
109 // The first returned value is the spacecraft state at the final epoch.
110 // The second value is the full trajectory where the step size is variable step used by the propagator.
111 let (future_sc, trajectory) = Propagator::default(dynamics)
112 .with(sc, almanac.clone())
113 .until_epoch_with_traj(epoch + Unit::Century * 0.03)?;
114
115 println!("=== High fidelity propagation ===");
116 println!(
117 "SMA changed by {:.3} km",
118 orbit.sma_km()? - future_sc.orbit.sma_km()?
119 );
120 println!(
121 "ECC changed by {:.6}",
122 orbit.ecc()? - future_sc.orbit.ecc()?
123 );
124 println!(
125 "INC changed by {:.3e} deg",
126 orbit.inc_deg()? - future_sc.orbit.inc_deg()?
127 );
128 println!(
129 "RAAN changed by {:.3} deg",
130 orbit.raan_deg()? - future_sc.orbit.raan_deg()?
131 );
132 println!(
133 "AOP changed by {:.3} deg",
134 orbit.aop_deg()? - future_sc.orbit.aop_deg()?
135 );
136 println!(
137 "TA changed by {:.3} deg",
138 orbit.ta_deg()? - future_sc.orbit.ta_deg()?
139 );
140
141 // We also have access to the full trajectory throughout the propagation.
142 println!("{trajectory}");
143
144 println!("Spacecraft params after 3 years without active control:\n{future_sc:x}");
145
146 // With the trajectory, let's build a few data products.
147
148 // 1. Export the trajectory as a parquet file, which includes the Keplerian orbital elements.
149
150 let analysis_step = Unit::Minute * 5;
151
152 trajectory.to_parquet(
153 "./03_geo_hf_prop.parquet",
154 ExportCfg::builder().step(analysis_step).build(),
155 )?;
156
157 // 2. Compute the latitude, longitude, and altitude throughout the trajectory by rotating the spacecraft position into the Earth body fixed frame.
158
159 // We iterate over the trajectory, grabbing a state every two minutes.
160 let mut offset_s = vec![];
161 let mut epoch_str = vec![];
162 let mut longitude_deg = vec![];
163 let mut latitude_deg = vec![];
164 let mut altitude_km = vec![];
165
166 for state in trajectory.every(analysis_step) {
167 // Convert the GEO bird state into the body fixed frame, and keep track of its latitude, longitude, and altitude.
168 // These define the GEO stationkeeping box.
169
170 let this_epoch = state.epoch();
171
172 offset_s.push((this_epoch - orbit.epoch).to_seconds());
173 epoch_str.push(this_epoch.to_isoformat());
174
175 let state_bf = almanac.transform_to(state.orbit, IAU_EARTH_FRAME, None)?;
176 let (lat_deg, long_deg, alt_km) = state_bf.latlongalt()?;
177 longitude_deg.push(long_deg);
178 latitude_deg.push(lat_deg);
179 altitude_km.push(alt_km);
180 }
181
182 println!(
183 "Longitude changed by {:.3} deg -- Box is 0.1 deg E-W",
184 orig_long_deg - longitude_deg.last().unwrap()
185 );
186
187 println!(
188 "Latitude changed by {:.3} deg -- Box is 0.05 deg N-S",
189 orig_lat_deg - latitude_deg.last().unwrap()
190 );
191
192 println!(
193 "Altitude changed by {:.3} km -- Box is 30 km",
194 orig_alt_km - altitude_km.last().unwrap()
195 );
196
197 // Build the station keeping data frame.
198 let mut sk_df = df!(
199 "Offset (s)" => offset_s.clone(),
200 "Epoch (UTC)" => epoch_str.clone(),
201 "Longitude E-W (deg)" => longitude_deg,
202 "Latitude N-S (deg)" => latitude_deg,
203 "Altitude (km)" => altitude_km,
204
205 )?;
206
207 // Create a file to write the Parquet to
208 let file = File::create("./03_geo_lla.parquet").expect("Could not create file");
209
210 // Create a ParquetWriter and write the DataFrame to the file
211 ParquetWriter::new(file).finish(&mut sk_df)?;
212
213 Ok(())
214}More examples
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 = Harmonics::from_stor(
124 almanac.frame_info(IAU_EARTH_FRAME)?,
125 HarmonicsMem::from_cof(&jgm3_meta.uri, 21, 21, true).unwrap(),
126 );
127
128 // Include the spherical harmonics into the orbital dynamics.
129 orbital_dyn.accel_models.push(harmonics_21x21);
130
131 // We define the solar radiation pressure, using the default solar flux and accounting only
132 // for the eclipsing caused by the Earth.
133 let srp_dyn = SolarPressure::default(EARTH_J2000, almanac.clone())?;
134
135 // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
136 // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
137 let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
138
139 println!("{dynamics}");
140
141 // Finally, let's propagate this orbit to the same epoch as above.
142 // The first returned value is the spacecraft state at the final epoch.
143 // The second value is the full trajectory where the step size is variable step used by the propagator.
144 let (future_sc, trajectory) = Propagator::default(dynamics)
145 .with(sc, almanac.clone())
146 .until_epoch_with_traj(future_orbit_tb.epoch)?;
147
148 println!("=== High fidelity propagation ===");
149 println!(
150 "SMA changed by {:.3} km",
151 orbit.sma_km()? - future_sc.orbit.sma_km()?
152 );
153 println!(
154 "ECC changed by {:.6}",
155 orbit.ecc()? - future_sc.orbit.ecc()?
156 );
157 println!(
158 "INC changed by {:.3e} deg",
159 orbit.inc_deg()? - future_sc.orbit.inc_deg()?
160 );
161 println!(
162 "RAAN changed by {:.3} deg",
163 orbit.raan_deg()? - future_sc.orbit.raan_deg()?
164 );
165 println!(
166 "AOP changed by {:.3} deg",
167 orbit.aop_deg()? - future_sc.orbit.aop_deg()?
168 );
169 println!(
170 "TA changed by {:.3} deg",
171 orbit.ta_deg()? - future_sc.orbit.ta_deg()?
172 );
173
174 // We also have access to the full trajectory throughout the propagation.
175 println!("{trajectory}");
176
177 // With the trajectory, let's build a few data products.
178
179 // 1. Export the trajectory as a CCSDS OEM version 2.0 file and as a parquet file, which includes the Keplerian orbital elements.
180
181 trajectory.to_oem_file(
182 "./01_cubesat_hf_prop.oem",
183 ExportCfg::builder().step(Unit::Minute * 2).build(),
184 )?;
185
186 trajectory.to_parquet_with_cfg(
187 "./01_cubesat_hf_prop.parquet",
188 ExportCfg::builder().step(Unit::Minute * 2).build(),
189 )?;
190
191 // 2. Compare the difference in the radial-intrack-crosstrack frame between the high fidelity
192 // and Keplerian propagation. The RIC frame is commonly used to compute the difference in position
193 // and velocity of different spacecraft.
194 // 3. Compute the azimuth, elevation, range, and range-rate data of that spacecraft as seen from Boulder, CO, USA.
195
196 let boulder_station = GroundStation::from_point(
197 "Boulder, CO, USA".to_string(),
198 40.014984, // latitude in degrees
199 -105.270546, // longitude in degrees
200 1.6550, // altitude in kilometers
201 almanac.frame_info(IAU_EARTH_FRAME)?,
202 );
203
204 // We iterate over the trajectory, grabbing a state every two minutes.
205 let mut offset_s = vec![];
206 let mut epoch_str = vec![];
207 let mut ric_x_km = vec![];
208 let mut ric_y_km = vec![];
209 let mut ric_z_km = vec![];
210 let mut ric_vx_km_s = vec![];
211 let mut ric_vy_km_s = vec![];
212 let mut ric_vz_km_s = vec![];
213
214 let mut azimuth_deg = vec![];
215 let mut elevation_deg = vec![];
216 let mut range_km = vec![];
217 let mut range_rate_km_s = vec![];
218 for state in trajectory.every(Unit::Minute * 2) {
219 // Try to compute the Keplerian/two body state just in time.
220 // This method occasionally fails to converge on an appropriate true anomaly
221 // from the mean anomaly. If that happens, we just skip this state.
222 // The high fidelity and Keplerian states diverge continuously, and we're curious
223 // about the divergence in this quick analysis.
224 let this_epoch = state.epoch();
225 match orbit.at_epoch(this_epoch) {
226 Ok(tb_then) => {
227 offset_s.push((this_epoch - orbit.epoch).to_seconds());
228 epoch_str.push(format!("{this_epoch}"));
229 // Compute the two body state just in time.
230 let ric = state.orbit.ric_difference(&tb_then)?;
231 ric_x_km.push(ric.radius_km.x);
232 ric_y_km.push(ric.radius_km.y);
233 ric_z_km.push(ric.radius_km.z);
234 ric_vx_km_s.push(ric.velocity_km_s.x);
235 ric_vy_km_s.push(ric.velocity_km_s.y);
236 ric_vz_km_s.push(ric.velocity_km_s.z);
237
238 // Compute the AER data for each state.
239 let aer = almanac.azimuth_elevation_range_sez(
240 state.orbit,
241 boulder_station.to_orbit(this_epoch, &almanac)?,
242 None,
243 None,
244 )?;
245 azimuth_deg.push(aer.azimuth_deg);
246 elevation_deg.push(aer.elevation_deg);
247 range_km.push(aer.range_km);
248 range_rate_km_s.push(aer.range_rate_km_s);
249 }
250 Err(e) => warn!("{} {e}", state.epoch()),
251 };
252 }
253
254 // Build the data frames.
255 let ric_df = df!(
256 "Offset (s)" => offset_s.clone(),
257 "Epoch" => epoch_str.clone(),
258 "RIC X (km)" => ric_x_km,
259 "RIC Y (km)" => ric_y_km,
260 "RIC Z (km)" => ric_z_km,
261 "RIC VX (km/s)" => ric_vx_km_s,
262 "RIC VY (km/s)" => ric_vy_km_s,
263 "RIC VZ (km/s)" => ric_vz_km_s,
264 )?;
265
266 println!("RIC difference at start\n{}", ric_df.head(Some(10)));
267 println!("RIC difference at end\n{}", ric_df.tail(Some(10)));
268
269 let aer_df = df!(
270 "Offset (s)" => offset_s.clone(),
271 "Epoch" => epoch_str.clone(),
272 "azimuth (deg)" => azimuth_deg,
273 "elevation (deg)" => elevation_deg,
274 "range (km)" => range_km,
275 "range rate (km/s)" => range_rate_km_s,
276 )?;
277
278 // Finally, let's see when the spacecraft is visible, assuming 15 degrees minimum elevation.
279 let mask = aer_df
280 .column("elevation (deg)")?
281 .gt(&Column::Scalar(ScalarColumn::new(
282 "elevation mask (deg)".into(),
283 Scalar::new(DataType::Float64, AnyValue::Float64(15.0)),
284 offset_s.len(),
285 )))?;
286 let cubesat_visible = aer_df.filter(&mask)?;
287
288 println!("{cubesat_visible}");
289
290 Ok(())
291}Source§impl ExportCfg
impl ExportCfg
Sourcepub fn from_metadata(metadata: Vec<(String, String)>) -> Self
pub fn from_metadata(metadata: Vec<(String, String)>) -> Self
Initialize a new configuration with the given metadata entries.
Sourcepub fn timestamped() -> Self
pub fn timestamped() -> Self
Initialize a new default configuration but timestamp the filename.
pub fn append_field(&mut self, field: StateParameter)
Trait Implementations§
Source§impl<'de> Deserialize<'de> for ExportCfg
impl<'de> Deserialize<'de> for ExportCfg
Source§fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>where
__D: Deserializer<'de>,
fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>where
__D: Deserializer<'de>,
Auto Trait Implementations§
impl Freeze for ExportCfg
impl RefUnwindSafe for ExportCfg
impl Send for ExportCfg
impl Sync for ExportCfg
impl Unpin for ExportCfg
impl UnsafeUnpin for ExportCfg
impl UnwindSafe for ExportCfg
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