-
Notifications
You must be signed in to change notification settings - Fork 1
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
* wcs implemented * add rotational rate for all COs
- Loading branch information
Showing
8 changed files
with
272 additions
and
145 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,23 @@ | ||
| const std = @import("std"); | ||
| const astroz = @import("astroz"); | ||
| const Tle = astroz.Tle; | ||
| const WorldCoordinateSystem = astroz.WorldCoordinateSystem; | ||
|
|
||
| pub fn main() !void { | ||
| var gpa = std.heap.GeneralPurposeAllocator(.{}){}; | ||
| defer _ = gpa.deinit(); | ||
| const allocator = gpa.allocator(); | ||
|
|
||
| const test_tle = | ||
| \\1 55909U 23035B 24187.51050877 .00023579 00000+0 16099-2 0 9998 | ||
| \\2 55909 43.9978 311.8012 0011446 278.6226 81.3336 15.05761711 71371 | ||
| ; | ||
|
|
||
| var tle = try Tle.parse(test_tle, allocator); | ||
| defer tle.deinit(); | ||
| const wcs = WorldCoordinateSystem.fromTle(test_tle, 0.0); | ||
|
|
||
| std.log.debug("WCS OUTPUT: {any}", wcs); | ||
|
|
||
| tle.output(); | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,82 @@ | ||
| //! World Coordinate System is commonly used | ||
| const std = @import("std"); | ||
| const constants = @import("constants.zig"); | ||
| const calculations = @import("calculations.zig"); | ||
| const Tle = @import("Tle.zig"); | ||
| const Spacecraft = @import("Spacecraft.zig"); | ||
|
|
||
| const Matrix3x3 = [3][3]f64; | ||
|
|
||
| const Vector3 = [3]f64; | ||
|
|
||
| const WorldCoordinateSystem = @This(); | ||
|
|
||
| x: f64, | ||
| y: f64, | ||
| z: f64, | ||
|
|
||
| /// Currently this function assumes a fully parsed TLE already | ||
| pub fn fromTle(tle: Tle, t0: f64) WorldCoordinateSystem { | ||
| std.log.info("TLE PARSING, {}", .{tle}); | ||
| const orbital_elements = calculations.tleToOrbitalElements(tle); | ||
|
|
||
| const eci = orbitalElementsToECI(orbital_elements); | ||
| const ecef = eciToECEF(eci, t0); | ||
|
|
||
| return .{ .x = ecef[0], .y = ecef[1], .z = ecef[2] }; | ||
| } | ||
|
|
||
| fn orbitalElementsToECI(elements: Spacecraft.OrbitalElements) Vector3 { | ||
| const r = elements.a * (1 - elements.e * elements.e) / (1 + elements.e * @cos(elements.true_anomaly)); | ||
| const x_orbit = r * @cos(elements.true_anomaly); | ||
| const y_orbit = r * @sin(elements.true_anomaly); | ||
|
|
||
| const R_w = Matrix3x3{ | ||
| .{ @cos(elements.arg_periapsis), -@sin(elements.arg_periapsis), 0 }, | ||
| .{ @sin(elements.arg_periapsis), @cos(elements.arg_periapsis), 0 }, | ||
| .{ 0, 0, 1 }, | ||
| }; | ||
|
|
||
| const R_i = Matrix3x3{ | ||
| .{ 1, 0, 0 }, | ||
| .{ 0, @cos(elements.i), -@sin(elements.i) }, | ||
| .{ 0, @sin(elements.i), @cos(elements.i) }, | ||
| }; | ||
|
|
||
| const R_o = Matrix3x3{ | ||
| .{ @cos(elements.raan), -@sin(elements.raan), 0 }, | ||
| .{ @sin(elements.raan), @cos(elements.raan), 0 }, | ||
| .{ 0, 0, 1 }, | ||
| }; | ||
|
|
||
| const R = calculations.multiplyMatrices(R_o, calculations.multiplyMatrices(R_i, R_w)); | ||
|
|
||
| return .{ | ||
| R[0][0] * x_orbit + R[0][1] * y_orbit, | ||
| R[1][0] * x_orbit + R[1][1] * y_orbit, | ||
| R[2][0] * x_orbit + R[2][1] * y_orbit, | ||
| }; | ||
| } | ||
|
|
||
| fn eciToECEF(eci: Vector3, time_since_epoch: f64) Vector3 { | ||
| const m = constants.earth.rotation_rate * time_since_epoch; | ||
| return .{ | ||
| eci[0] * @cos(m) + eci[1] * @sin(m), | ||
| -eci[0] * @sin(m) + eci[1] * @cos(m), | ||
| eci[2], | ||
| }; | ||
| } | ||
|
|
||
| test WorldCoordinateSystem { | ||
| const raw_tle = | ||
| \\1 55909U 23035B 24187.51050877 .00023579 00000+0 16099-2 0 9998 | ||
| \\2 55909 43.9978 311.8012 0011446 278.6226 81.3336 15.05761711 71371 | ||
| ; | ||
| const expected_ecs: WorldCoordinateSystem = .{ .x = 4.628063569540487e3, .y = -5.164768842168279e3, .z = 7.220776206732921e0 }; | ||
|
|
||
| var test_tle = try Tle.parse(raw_tle, std.testing.allocator); | ||
| defer test_tle.deinit(); | ||
| const wcs = WorldCoordinateSystem.fromTle(test_tle, 0.0); | ||
|
|
||
| try std.testing.expectEqualDeep(expected_ecs, wcs); | ||
| } |
Oops, something went wrong.