Spacecraft Dynamics

Model dynamics of one or more spacecraft

• Library:
• Aerospace Blockset / Spacecraft / Spacecraft Dynamics

Description

The Spacecraft Dynamics block models translational and rotational dynamics of spacecraft using numerical integration. It computes the position, velocity, attitude, and angular velocity of one or more spacecraft over time. For the most accurate results, use a variable step solver with low tolerance settings (less than 1e-8). To trade off accuracy for speed, use larger tolerances, depending on your mission requirements.

You can define initial orbital states as

• A set of orbital elements.

• Position and velocity state vectors.

To propagate orbital states, the block uses the gravity model selected for the current central body. It also includes external accelerations and forces that you provide as inputs to the block. To define initial attitude states, use quaternions, direction cosine matrices (DCMs), or Euler angles.

To propagate attitude states, the block uses moments provided as inputs to the block and mass properties defined on the block.

Aerospace Blockset™ uses quaternions that are defined using the scalar-first convention.

The Spacecraft Dynamics block supports scalar and vector expansion. The block parameter and input port dimensions determine the number of the output signals and the number of spacecraft. After scalar and vector expansion, all parameters in the Orbit, Mass, and Attitude tabs and all input ports except for φθψ (Moon libration angles) and αδW (right ascension, declination, and rotation angle) input ports are defined for each spacecraft.

The size of the provided initial conditions determines the number of spacecraft being modeled. If you supply more than one value for a parameter in the Orbit, Attitude, or Mass tabs, the block outputs a constellation of satellites. Any parameter with a single provided value is expanded and applied to all the satellites in the constellation. For example, if you provide a single value for all the parameters on the block except True anomaly, which contains six values, the block creates a constellation of six satellites, varying true anomaly only.

The block applies the same expansion behavior to the block input ports. All input ports support expansion except Moon libration angles (when Central body is `Moon`) and Spin axis right ascension (RA) at J2000, Spin axis declination (Dec) at J2000, and Initial rotation angle at J2000 (when Central body is `Custom`). All other ports accept either a single value expanded to all spacecraft being modeled, or individual values applied to each spacecraft.

For more information on the coordinate systems and rotational and translational dynamics the Spacecraft Dynamics block uses, see Algorithms.

To help model the drag on spacecraft for high precision orbit propagation, the Orbit Propagator block supports atmospheric drag. Atmospheric drag affects spacecraft flying at low Earth orbit (LEO); it is less relevant further away from Earth. For the atmospheric drag equation, see Atmospheric Drag.

Ports

Input

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Force applied to the spacecraft center of mass in the body frame, specified as a 3-element vector or numSat-by-3 array at the current time step. numSat is the number of spacecraft.

Dependencies

To enable this port, select the Input body forces check box.

Data Types: `double`

Moment applied to the spacecraft with respect of mass in the body frame, specified as a 3-element vector or numSat-by-3 array at the current time step. numSat is the number of spacecraft.

Dependencies

To enable this port, select the Input body moments check box.

Data Types: `double`

External acceleration to apply to the spacecraft with respect to the ICRF or fixed-frame at the current timestep, specified as a 3-element vector or m-by-3 array.

Dependencies

To enable this port, select the Input external accelerations check box.

To specify the acceleration coordinate frame, set the External acceleration coordinate frame parameter.

Data Types: `double`

Moon libration angles for transformation between the ICRF and Moon-centric fixed-frame using the Moon-centric Principal Axis (PA) system, specified as a 3-element vector. To get these values, use the Moon Libration block.

Note

The fixed-frame used by this block when Central body is set to `Moon` is the Mean Earth/pole axis (ME) system. For more information, see Algorithms.

Dependencies

To enable this port:

• Set Central body to `Moon`.

• Select the Input Moon libration angles check box.

Data Types: `double`

Central body spin axis instantaneous right ascension, declination, and rotation angle, specified as a 3-element vector. This port is available only for custom central bodies.

Dependencies

To enable this port:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Port`.

Data Types: `double`

Spacecraft mass at the current timestep. numSat is the number of spacecraft.

Dependencies

To enable this port, set Mass type to ```Custom Variable```.

Data Types: `double`

Rate of change of mass (positive if accreted, negative if ablated) at the current timestep, specified as a scalar or 1D array of size numSat. numSat is the number of spacecraft.

Dependencies

To enable this port, set Mass type to ```Simple Variable```.

Data Types: `double`

Spacecraft inertia tensor, specified as a 3-by-3 array or 3-by-3-by-numSat array at the current timestep. numSat is the number of spacecraft.

Dependencies

To enable this port, set Mass type to ```Custom Variable```.

Data Types: `double`

Rate of change of inertia tensor matrix, specified as a 3-by-3 array or 3-by-3-by-numSat array at the current time step. numSat is the number of spacecraft.

Dependencies

To enable this port, set Mass type to ```Custom Variable```.

Data Types: `double`

Relative velocity at which the mass is accreted to or ablated from the body in body-fixed axes, specified as a 3-element vector or numSat-by-3 array. numSat is the number of spacecraft.

Dependencies

To enable this port:

• Set Mass type to ```Custom Variable``` or `Simple Variable`.

• Select the Include mass flow relative velocity check box.

Data Types: `double`

Atmospheric density to calculate acceleration due to atmospheric drag.

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Port`.

Data Types: `double`

81-day average Ottawa F10.7 cm solar flux, centered on the current day specified in Start date/time. These F107 Average values correspond to the 10.7 cm radio flux at the actual distance of the Earth from the Sun. This site provides both classes of values:

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Dialog`.

Data Types: `double`

Daily Ottawa F10.7 cm solar flux, centered on the current day specified in Start date/time. The f107Daily values do not correspond to the radio flux at 1 AU. This site provides both classes of values:

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Dialog`.

Data Types: `double`

Daily magnetic index information (aph), specified as an N-by-7 array. The magnetic index information consists of:

 Daily magnetic index (AP) 3 hour AP for current time 3 hour AP for 3 hours before current time 3 hour AP for 6 hours before current time 3 hour AP for 9 hours before current time Average of eight 3 hour AP indices from 12 to 33 hours before current time Average of eight 3 hour AP indices from 36 to 57 hours before current time

The effects of daily magnetic index are not large or established below 80,000 m. For more information, see Limitations on NRLMSISE-00 Atmosphere Model.

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Dialog`.

Data Types: `double`

Variation flags, specified as an array of 23, to enable or disable particular variations for the outputs. You can specify one of the following values for a field. The default value for each field is `1`.

• 0.0

Removes the value effect on the output.

• 1.0

Applies the main and the cross-term effects of that value on the output.

• 2.0

Applies only the cross-term effect of that value on the output.

FieldDescription
`Flags(1) `

F10.7 effect on mean

`Flags(2) `

Independent of time

`Flags(3) `

Symmetrical annual

`Flags(4) `

Symmetrical semiannual

`Flags(5) `

Asymmetrical annual

`Flags(6) `

Asymmetrical semiannual

`Flags(7) `

Diurnal

`Flags(8) `

Semidiurnal

`Flags(9) `

Daily AP. If you set this field to -1, the block uses the entire matrix of magnetic index information (APH) instead of `APH(:,1)`

`Flags(10) `

All UT, longitudinal effects

`Flags(11) `

Longitudinal

`Flags(12) `

UT and mixed UT, longitudinal

`Flags(13) `

Mixed AP, UT, longitudinal

`Flags(14) `

Terdiurnal

`Flags(15) `

Departures from diffusive equilibrium

`Flags(16) `

All exospheric temperature variations

`Flags(17) `

All variations from 120,000 meter temperature (TLB)

`Flags(18) `

All lower thermosphere (TN1) temperature variations

`Flags(19) `

All 120,000 meter gradient (S) variations

`Flags(20) `

All upper stratosphere (TN2) temperature variations

`Flags(21) `

All variations from 120,000 meter values (ZLB)

`Flags(22) `

All lower mesosphere temperature (TN3) variations

`Flags(23) `

Turbopause scale height variations

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Dialog`.

• Set the Flags source parameter to `Port`.

Data Types: `double`

Atmospheric drag coefficient, specified as a scalar or vector of size numSat.

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Drag coefficient source parameter to `Port`.

Data Types: `double`

Atmospheric drag area, specified as a scalar or vector of size numSat.

Dependencies

To enable this port:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Drag area source parameter to `Port`.

Data Types: `double`

Output

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Position of the spacecraft with respect to the ICRF or fixed-frame outport coordinate frame, returned as a 3-element vector or numSat-by-3 array at the current time step. numSat is the number of spacecraft.

Dependencies

• To change the output coordinate frame for this port, set the State vector output coordinate frame parameter.

• The size of the initial conditions provided in the Mass, Orbit, or Attitude tab control the port dimension.

Data Types: `double`

Velocity of the spacecraft with respect to the ICRF or fixed-frame outport coordinate frame, returned as a 3-element vector or numSat-by-3 array at the current time step. numSat is the number of spacecraft.

Dependencies

• To change the output coordinate frame for this port, set the State vector output coordinate frame parameter.

• The size of the initial conditions provided in the Mass, Orbit, or Attitude tab control the port dimension.

Data Types: `double`

Total inertial acceleration of the spacecraft with respect to the ICRF, returned as a 3-element vector or numSat-by-3 array at the current timestep. numSat is the number of spacecraft.

Dependencies

• To enable this port, select the Output total inertial acceleration check box

• The size of the initial conditions provided in the Orbit tab control the port dimension.

Data Types: `double`

Spacecraft attitude quaternion, returned as a (scalar first) quaternion rotation from the body axis to the outport frame, as a 4-element quaternion, or numSat-by-4 array (scalar first) at the current time step. numSat is the number of spacecraft.

Dependencies

The coordinate frame and attitude format of this port depends on these settings:

• To specify the attitude reference coordinate frame, set the Attitude reference coordinate frame parameter.

• Set Attitude representation to `Quaternion`.

Data Types: `double`

Spacecraft attitude direction cosine matrix (DCM), returned as a3-by-3 array or numSat-by-3-by-3 array. numSat is the number of spacecraft.

Dependencies

The coordinate frame and attitude format of this port depends on these settings:

• To specify the attitude reference coordinate frame, set the Attitude reference coordinate frame parameter.

• Set Attitude representation to `DCM`.

Data Types: `double`

Spacecraft attitude Euler angles, returned as a 3-element vector or numSat-by-3 array. numSat is the number of spacecraft.

Dependencies

The coordinate frame and attitude format of this port depend on these settings:

• To specify the attitude reference coordinate frame, set the Attitude reference coordinate frame parameter.

• Set Attitude representation to ```Euler angles```.

Data Types: `double`

Angular rate of the spacecraft relative to the attitude reference coordinate frame, returned as a 3-element vector or numSat-by-3 array, expressed as body axis angular rates PQR. numSat is the number of spacecraft.

Dependencies

The attitude reference coordinate frame depends on the Attitude reference coordinate frame parameter.

Data Types: `double`

Body angular acceleration relative to the ICRF frame, returned as a 3-element array or numSat-by-3 array. numSat is the number of spacecraft.

Dependencies

To enable this port, select the Output total inertial angular acceleration check box.

The attitude reference coordinate frame depends on the Attitude reference coordinate frame parameter.

Data Types: `double`

Coordinate system transformation between the ICRF and fixed-frame coordinate system at the current timestep, returned as a 4-element array.

Dependencies

To enable this port, select the Output quaternion (ICRF to Fixed-frame) check box.

Data Types: `double`

Time at current time step, returned as a:

• scalar — If you specify the Start data/time parameter as a Julian date.

• 6-element array — If you specify the Start data/time parameter as a Gregorian date with six elements (year, month, day, hours, minutes, seconds).

This value equals the Start date/time parameter value plus the elapsed simulation time.

Dependencies

To enable this parameter, select the Output current date/time (UTC Julian date) check box.

Data Types: `double`

Fuel tank status at the current timestep, returned as a scalar or numSat-element array, returned as:

• `1` — Tank is full.

• `0` — Tank is not full or empty.

• `-1` — Tank is empty.

numSat is the number of spacecraft.

Dependencies

To enable this parameter, select the Output fuel tank status check box.

Data Types: `double`

Parameters

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Main

To enable external forces to be included in the integration of the spacecraft equations of motion in the body frame, select this check box. Otherwise, clear this check box.

Programmatic Use

 Block Parameter: `forcesin` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

To enable external moments to be included in the integration of the spacecraft equations of motion in the body frame, select this check box. Otherwise, clear this check box.

Programmatic Use

 Block Parameter: `momentsIn` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

To enable additional external accelerations to be included in the integration of the spacecraft equations of motion, select this check box. Otherwise, clear this check box.

Programmatic Use

 Block Parameter: `accelIn` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

Frame for acceleration input port A, specified as `ICRF` or `Fixed-frame`.

Dependencies

To enable this parameter, select the Input external accelerations check box.

Programmatic Use

 Block Parameter: `accelFrame` Type: character vector Values: `'ICRF'` | `'Fixed-frame'` Default: `'ICRF'`

Position and velocity state output port coordinate frame setup, specified as `ICRF` or `Fixed-frame`.

Programmatic Use

 Block Parameter: `outportFrame` Type: character vector Values: `'ICRF'` | `'Fixed-frame'` Default: `'ICRF'`

Data Types: `string`

Enable the total acceleration output computed by the block with respect to the ICRF or fixed-frame outport coordinate frame. This acceleration includes all external accelerations, forces, and internal environmental accelerations that act on the spacecraft.

Note

Do not use this port as part of a simulation loop (in other words, do not feed this output back into the block).

Tunable: Yes

Dependencies

To change the output coordinate frame for this port, set the State vector output coordinate frame parameter.

Programmatic Use

 Block Parameter: `AccelOut` Type: character vector Values: `'on'` | `'off'` Default: `'off'`

Data Types: `string`

Initial start date and time of simulation, specified as a Julian or Gregorian date. The block defines initial conditions using this value.

Tip

To calculate the Julian date, use the `juliandate` function.

Tunable: Yes

Dependencies

The data format for this parameter is controlled by the Time format parameter.

Programmatic Use

 Block Parameter: `startDate` Type: character vector Values:``` 'juliandate(2020, 1, 1, 12, 0, 0)'``` | valid scalar Julian date | valid Gregorian date including year, month, day, hours, minutes, seconds as 1D or 6-element array Default: ` 'juliandate(2020, 1, 1, 12, 0, 0)'`

To output the current date or time, select this check box. Otherwise, clear this check box.

Dependencies

The data format for this parameter is controlled by the Time format parameter.

Programmatic Use

 Block Parameter: `dateOut` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

Out-of-range block behavior action. Specify one of these options.

ActionDescription
`None` No action.
`Warning` Warning displays in the MATLAB® Command Window. Model simulation continues.
`Error` (default) MATLAB returns an exception. Model simulation stops.

Programmatic Use

 Block Parameter: `action` Type: character vector Values: `'None'` | `'Warning'` | `'Error'` Default: `'Warning'`

Mass

Spacecraft mass type, specified as:

• `Fixed` — Mass and inertia are constant throughout the simulation.

• `Simple Variable` — Mass and inertia vary linearly as a function of mass rate.

• `Custom Variable` — Instantaneous mass, inertia, and inertia rate are inputs to the block.

Programmatic Use

 Block Parameter: `massType` Type: character vector Values: `'Fixed'` | `'Simple Variable'` | ```'Custom Variable'``` Default: `'Fixed'`

Data Types: `double`

Initial mass of rigid body spacecraft, specified as scalar or vector of size numSat. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set the Mass type parameter to either Fixed or Simple variable.

Programmatic Use

 Block Parameter: `mass` Type: character vector Values: scalar | vector of size numSat Default: `'4.0'`

Spacecraft empty (dry) mass, specified as a scalar or vector of size numSat. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `emptyMass` Type: character vector Values: 1D array of size numSat | 1D array of size numSat Default: `'3.5'`

Data Types: `double`

Spacecraft full (wet) mass, specified as a scalar or vector of size numSat. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `fullMass` Type: character vector Values: scalar | vector of size numSat Default: `'4.0'`

Data Types: `double`

Initial inertia tensor matrix of the spacecraft, specified, as a 3-by-3 array for a single spacecraft or a 3-by-3-by-numSat array for multiple spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Mass type to `Fixed`.

Programmatic Use

 Block Parameter: `inertia` Type: character vector Values: `'[0.2273, 0, 0; 0 0.2273 0; 0 0 .0040]'` | 3-by-3 array | 3-by-3-by-numSat array Default: `'[0.2273, 0, 0; 0 0.2273 0; 0 0 .0040]'`

Empty (dry) inertia tensor matrix, specified as a 3-by-3 array for a single spacecraft or a 3-by-3-by-numSat array for multiple spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `emptyInertia` Type: character vector Values: 3-by-3 array | 3-by-3-by-numSat array Default: `[0.1989, 0, 0; 0 0.1989 0; 0 0 .0035]`

Full (wet) inertia tensor matrix, specified as a 3-by-3 array for a single spacecraft or a 3-by-3-by-numSat array for multiple spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `fullInertia` Type: character vector Values: 3-by-3 array | 3-by-3-by-numSat array Default: `[0.2273, 0, 0; 0, 0.2273, 0; 0, 0, .0040]`

To enable mass flow velocity to the block, select this check box. The mass flow velocity is the relative velocity in the body frame at which the mass is accreted or ablated. To disable mass flow velocity to the block, clear this check box.

Dependencies

To enable this parameter, set Mass type to `Simple variable` or ```Custom variable```.

Programmatic Use

 Block Parameter: `useMassFlowRelativeVelocity` Type: character vector Values: `'on'` | `'off'` Default: `'off'`

Data Types: `double`

To limit the mass flow when the spacecraft mass is full or empty, select this check box. Otherwise, clear this check box.

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `limitMassFlow` Type: character vector Values: `'on'` | `'off'` Default: `'on'`

Data Types: `double`

To enable fuel tank status, select this check box. Otherwise, clear this check box.

Dependencies

To enable this parameter, set Mass type to `Simple variable`.

Programmatic Use

 Block Parameter: `outputFuelStatus` Type: character vector Values: `'on'` | `'off'` Default: `'on'`

Data Types: `double`

Orbit

Define the initial states of the spacecraft.

Input method for initial states of orbit, specified as ```Orbital elements```, `ICRF state vector`, or `Fixed-frame state vector`.

Programmatic Use

 Block Parameter `stateFormatNum` when `propagator` is set to `High precision (numerical)` Type: character vector Values: `'Orbital elements'` | `'Orbital elements'` | `'ICRF state vector'` | `'Fixed-frame state'` when `propagator` is set to ```'High precision (numerical)'``` Default: `'Orbital elements'`

Orbit classification, specified as:

• `Keplerian` — Model elliptical, parabolic, and hyperbolic orbits using six standard Keplerian orbital elements.

• `Elliptical equatorial` — Fully define an equatorial orbit, where inclination is 0 or 180 degrees and the right ascension of the ascending node is undefined.

• `Circular` — Define a circular orbit, where eccentricity is 0 and the argument of periapsis is undefined. To fully define a circular orbit, select `Circular equatorial`.

• `Circular equatorial` — Fully define a circular orbit, where eccentricity is 0 and the argument of periapsis is undefined.

Dependencies

To enable this parameter, set Initial state format to `Orbital elements`.

Programmatic Use

 Block Parameter: `orbitType` Type: character vector Values: `'Keplerian'` | `'Elliptical equatorial'` | `'Circular inclined'` | ```'Circular equatorial'``` Default: `'Keplerian'`

Half of ellipse major axis, specified as a 1D array of size numSat. numSat is the number of spacecraft.

• For parabolic orbits, this block interprets this parameter as the periapsis radius (distance from periapsis to the focus point of orbit).

• For hyperbolic orbits, this block interprets this parameter as the distance from periapsis to the hyperbola center.

Tunable: Yes

Dependencies

To enable this parameter, set Initial state format to `Orbital elements`.

Programmatic Use

 Block Parameter: `semiMajorAxis` Type: character vector Values: scalar | 1D array of size numSat Default: `'6786000'`

Deviation of the orbit from a perfect circle, specified as a scalar or 1D array of size numSat. numSat is the number of spacecraft.

If Orbit type is set to `Keplerian`, this value can be:

• `1` for parabolic orbit

• Greater than `1` for hyperbolic orbit

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit type to `Keplerian` or `Elliptical equatorial`.

Programmatic Use

 Block Parameter: `eccentricity` Type: character vector Values: `0.01` | scalar | value between `0` and `1`, or greater than `1` for Keplerian orbit type | 1D array of size numSat Default: `'0.01'`

Vertical tilt of the ellipse with respect to the reference plane measured at the ascending node, specified as a scalar or 1D array of size numSat, in specified units. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```

• Set Orbit type to `Keplerian` or `Circular inclined`

Programmatic Use

 Block Parameter: `inclination` Type: character vector Values: 50 | scalar | 1D array of size numSat | degrees between 0 and 180 | radians between 0 and pi Default: `'50'`

Right ascension of ascending node (RAAN), specified as a value between `0` and `360`, specified as a scalar or 1D array of size numSat, in specified units. numSat is the number of spacecraft. RAAN is the angular distance along the reference plane from the International Celestial Reference Frame (ICRF) x-axis to the location of the ascending node — the point at which the spacecraft crosses the reference plane from south to north.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit type to `Keplerian` or `Circular inclined`.

Programmatic Use

 Block Parameter: `raan` Type: character vector Values: `'95'` | scalar value between `0` and `360` | 1D array of size numSat Default: `'95'`

Angle from the spacecraft ascending node to periapsis (closest point of orbit to the central body), specified as a 1D array of size numSat, in specified units. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```

• Set Orbit type to `Keplerian`

Programmatic Use

 Block Parameter: `argPeriapsis` Type: character vector Values: 93 | scalar value between `0` and `360` | 1D array of size numSat Default: `'93'`

Angle between periapsis (closest point of orbit to the central body) and the initial position of spacecraft along its orbit at Start date/time, specified as a scalar or 1D array of size numSat, in specified units. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit type to `Keplerian` or `Elliptical inclined`.

Programmatic Use

 Block Parameter: `trueAnomaly` Type: character vector Values: `'203'` | scalar value between `0` and `360` | 1D array of size numSat Default: `'203'`

Angle between the ascending node and the initial position of spacecraft along its orbit at Start date/time, specified as a scalar or 3-element vector or 1D array of size numSat, in specified units. numSat is number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit Type to ```Circular inclined```.

Programmatic Use

 Block Parameter: `argLat` Type: character vector Values: `'200'` | scalar value between `0` and `360` | 1D array of size numSat Default: `'200'`

Angle between the ICRF x-axis and the eccentricity vector, specified as a scalar or 3-element vector or 1D array of size numSat, in specified units. numSat is the number of spacecraft

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit type to ```Elliptical equatorial```.

Programmatic Use

 Block Parameter: `lonPeriapsis` Type: character vector Values: 100 | scalar value between `0` and `360` | 1D array of size numSat Default: `'100'`

Angle between the ICRF x-axis and the initial position of spacecraft along its orbit at Start date/time, specified as a scalar or 1D array of size numSat or a numSat-by-3 vector, in specified units. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Initial state format to ```Orbital elements```.

• Set Orbit type to ```Circular equatorial```.

Programmatic Use

 Block Parameter: `trueLon` Type: character vector Values: `'150'` | scalar value between `0` and `360` | 1D array of size numSat | numSat-by-3 vector Default: `'150'`

Cartesian position vector of spacecraft in ICRF coordinate system at Start date/time, specified as a 3-element vector for single spacecraft or a numSat-by-3 array for multiple spacecraft. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Initial state format to `ICRF state vector`.

Programmatic Use

 Block Parameter: `inertialPosition` Type: character vector Values: `[3649700.0 3308200.0 -4676600.0]` | 3-element vector | numSat-by-3 array Default: `'[3649700.0 3308200.0 -4676600.0]'`

Cartesian velocity vector of spacecraft in ICRF coordinate system at Start date/time, specified as a 3-element vector for single spacecraft or a numSat-by-3 array for multiple spacecraft. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Initial state format to `ICRF state vector`.

Programmatic Use

 Block Parameter: `inertialVelocity` Type: character vector Values: `[-2750.8 6666.4 2573.4]` | 3-element vector | 2-D array of size numSat-by-3 array Default: `'[-2750.8 6666.4 2573.4]'`

Cartesian position vector of spacecraft in fixed-frame coordinate system at Start date/time, specified as a 3-element vector for single spacecraft or a numSat-by-3 array for multiple spacecraft. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Initial state format to `Fixed-frame state vector`.

Programmatic Use

 Block Parameter: `fixedPosition` Type: character vector Values: `'[-4142689.0 -2676864.7 -4669861.6]'` | 3-element vector for single spacecraft | numSat-by-3 array Default: `'[-2750.8 6666.4 2573.4]'`

Cartesian velocity vector of spacecraft in fixed-frame coordinate system at Start date/time, specified as a 3-element vector for single spacecraft or a numSat-by-3 array for multiple spacecraft. numSat is the number of spacecraft.

Tunable: Yes

Dependencies

To enable this parameter, set Initial state format to `Fixed-frame state vector`.

Programmatic Use

 Block Parameter: `fixedVelocity` Type: character vector Values: `'[1452.7 -6720.7 2568.1]'` | 3-element vector | numSat-by-3 array Default: `'[1452.7 -6720.7 2568.1]'`

Attitude

Attitude and angular rate coordinate frame with respect to the attitude and angular rate initial conditions, specified as:

• `ICRF`

• `Fixed-frame`

• `NED`

• `LVLH`

Programmatic Use

 Block Parameter: `attitudeFrame` Type: character vector Values: `'ICRF'` | `'Fixed-frame'` | `'NED'` | `'LVLH'` Default: `'ICRF'`

Data Types: `string`

Orientation format for spacecraft attitude (initial condition and output port), specified as `Quaternion`, `DCM`, or `Euler angles`.

Programmatic Use

 Block Parameter: `attitudeFrame` Type: character vector Values: `'Quaternion'` | `'DCM'` | ```'Euler angles'``` Default: `'Quaternion'`

Data Types: `double`

Spacecraft initial attitude (orientation) of the spacecraft provided as either a quaternion, DCM, or Euler angle set with respect to Attitude representation.

Tunable: Yes

Dependencies

This parameter name and value format changes depending on the Attitude representation parameter.

Parameter NameAttitude Representation SettingValue Format

Initial quaternion

`Quaternion`

• 4-element vector

• numSat-by-4 array

Initial DCM

`DCM`

• 3-by-3 array

• numSat-by-3-by-3 array

Initial Euler angles

`Euler angles`

• 3-element vector

• numSat-by-3 array

Programmatic Use

 Block Parameter: `attitude` Type: character vector Values: 4-element vector | numSat-by-4 array | 3-by-3 array | numSat-by-3-by-3 array | 3-element array | numSat-by-3 array Default: `'[1, 0, 0, 0]'`

Data Types: `double`

Rotation angle sequence for Euler angle attitude representation.

Tunable: Yes

Dependencies

To enable this parameter, set Attitude representation to `Euler angles`.

Programmatic Use

 Block Parameter: `rotationOrder` Type: character vector Values: `'ZYX'` | `'ZYZ'` |`'ZXY'` | `'ZXZ'` | `'YXZ'` | `'YXY'` | `'YZX'` | `'YZY'` | `'XYZ'` | `'XYX'` | `'XZY'` | `'XZX'` Default: `'ZYX'`

Data Types: `double`

Initial body-fixed angular rates (PQR) with respect to Attitude reference coordinate frame.

Tunable: Yes

Programmatic Use

 Block Parameter: `attitudeRate` Type: character vector Values: | 3-element vector | numSat-by-3 array Default: `[0, 0, 0]`

Data Types: `double`

Enable output total vehicle acceleration computed by the block with respect to the ICRF attitude reference coordinate frame. This acceleration includes all moments that act on the spacecraft.

Tunable: Yes

Programmatic Use

 Block Parameter: `angAccelOut` Type: character vector Values: `'on'` | `'off'` Default: `'off'`

Data Types: `string`

Select this check box to enable the use of the gravity gradient torque in the block rotational dynamics equations. Otherwise, clear this check box.

Tunable: Yes

Programmatic Use

 Block Parameter: `angAccelOut` Type: character vector Values: `'on'` | `'off'` Default: `'on'`

Data Types: `double`

Central Body

Celestial body, specified as `Earth`, `Moon`, `Mercury`, `Venus`, `Mars`, `Jupiter`, `Saturn`, `Uranus`, `Neptune`, or `Custom`, around which the spacecraft defined in the Orbit tab orbits.

Programmatic Use

 Block Parameter: `centralBody` Type: character vector Values: `'Earth'` | `'Moon'` |`'Mercury'` | `'Venus'` | `'Mars'` | `'Jupiter'` | `'Saturn'` | `'Uranus'` | `'Neptune'` | `'Custom'` | Default: `'Earth'`

Control the gravity model for the central body by specifying as `Spherical harmonics`, `Point-mass`, or ```Oblate ellipsoid (J2)```.

Dependencies

Available options are based on Central body settings.

Earth, Moon, Mars, or CustomMercury, Venus, Jupiter, Saturn, Uranus, or Neptune
`Spherical harmonics``Oblate ellipsoid (J2)`
`Point-mass``Point-mass`
`Oblate ellipsoid (J2)`

Programmatic Use

 Block Parameter: `gravityModel` when `centralBody` set to `'Earth'`, `'Moon'`, `'Mars'`, or `'Custom'` | `gravityModelnoSH` when `centralBody` set to `Mercury`, `Venus`, `Jupiter`, `Saturn`, `Uranus`, or `Neptune` Type: character vector Values: `'Spherical harmonics'` | `'Point-mass'` | `'Oblate ellipsoid (J2)'` when `centralBody` set to `'Earth'`, `'Moon'`, `'Mars'`, or `'Custom'`; `'Point-mass'` | `'Oblate ellipsoid (J2)'` when `centralBody` set to `Mercury`, `Venus`, `Jupiter`, `Saturn`, `Uranus`, or `Neptune` Default: `'Spherical harmonics'` when `centralBody` set to `'Earth'`, `'Moon'`, `'Mars'`, or `'Custom'`; ```'Oblate ellipsoid (J2)'``` when `centralBody` set to `Mercury`, `Venus`, `Jupiter`, `Saturn`, `Uranus`, or `Neptune`

Spherical harmonic gravitational potential model, specified according to the specified Central body.

Dependencies

Available options are based on Central body settings:

Central bodySpherical Harmonic Model Option
EarthEGM2008, EGM96, or EIGEN-GL04C
MoonLP-100K or LP-165P
MarsGMM2B

Programmatic Use

 Block Parameter: `'earthSH'` when `centralBody` set to `'Earth'` | `'moonSH'` when `centralBody` set to `'Moon'` | `'marsSH'` when `centralBody` set to `'Mars'` Type: character vector Values: `'EGM2008'` | `'EGM96'` | `'EIGEN-GL04C'` when `centralBody` set to `'earthSH'`; `'LP-100K'` | `'LP-165P'` when `centralBody` set to `'moonSH'`; `'GMM2B'` when `centralBody` set to `'marsSH'` Default: `'Spherical harmonics'`

Rotational rate of a custom central body, specified as a scalar.

Dependencies

To enable this parameter, set Central body to `Custom`.

Programmatic Use

 Block Parameter: `'customOmega'` Type: character vector Values: `'4.06124975e-3'` | scalar Default: `'4.06124975e-3'`

Data Types: `double`

Harmonic coefficient MAT-file that contains definitions for a custom planetary model, specified as a character vector or string.

This file must contain these variables:

VariableDescription
Re

Scalar of planet equatorial radius in meters (m).

GM

Scalar of planetary gravitational parameter in meters cubed per second squared (m3/s2)

.
degree

Scalar of maximum degree.

C

(degree+1)-by-(degree+1) matrix containing normalized spherical harmonic coefficients matrix, C.

S

(degree+1)-by-(degree+1) matrix containing normalized spherical harmonic coefficients matrix, S.

Dependencies

To enable this parameter:

• SetCentral body to `Custom`.

• Set Gravitational potential model to``` Spherical harmonics```.

Programmatic Use

 Block Parameter: `shFile` Type: character vector Values: `'aerogmm2b.mat'` | harmonic coefficient MAT-file Default: `'aerogmm2b.mat'`

Degree of harmonic model, specified as a scalar.

Planet ModelRecommended DegreeMaximum Degree

`EGM2008`

120

2159

`EGM96`

70

360

`LP100K`

60

100

`LP165P`

60

165

`GMM2B`

60

80

`EIGENGL04C`

70

360

Dependencies

To enable this parameter:

• Set Central body to `Earth`, `Moon`, `Mars`, or `Custom`.

• Set Gravitational potential model to ``` Spherical harmonics```.

Programmatic Use

 Block Parameter: `shDegree` Type: character vector Values: `'80'` | scalar Default: `'80'`

Select this check box to use Earth orientation parameters for the transformation between the ICRF and fixed-frame coordinate systems. Otherwise, clear this check box.

Dependencies

To enable this parameter, set Central body to `Earth`.

Programmatic Use

 Block Parameter: `useEOPs` Type: character vector Values: `'on'` | `'off'` Default: `'on'`

Custom list of Earth orientation data, specified in a MAT-file.

Dependencies

To enable this parameter:

• Select the Use Earth orientation parameters (EOPs) check box.

• Set Central body to `Earth`.

Programmatic Use

 Block Parameter: `eopFile` Type: character vector Values: `'aeroiersdata.mat'` | `MAT-file` Default: `'aeroiersdata.mat'`

To specify Euler libration angles (φ θ ψ) for Moon orientation, select this check box.

Dependencies

To enable this parameter, set Central body to `Moon`.

Programmatic Use

 Block Parameter: `useMoonLib` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

To add output transformation quaternion port for the quaternion transformation from the ICRF to the fixed-frame coordinate system, select this check box. Otherwise, clear this check box.

Programmatic Use

 Block Parameter: `outputTransform` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

Central body spin axis source, specified as `Port` or `Dialog`. The block uses the spin axis to calculate the transformation from the ICRF to the fixed-frame coordinate system for the custom central body.

Dependencies

To enable this parameter, set Central body to `Custom`.

Programmatic Use

 Block Parameter: `cbPoleSrc` Type: character vector Values: `'Port'` | `'Dialog'` Default: `'Port'`

Right ascension of central body spin axis at J2000 (2451545.0 JD, 2000 Jan 1 12:00:00 TT), specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbRA` Type: character vector Values: `'317.68143'` | double scalar Default: `'317.68143'`

Right ascension rate of the central body spin axis, specified as a double scalar, in specified angle units/century.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbRARate` Type: character vector Values: `'-0.1061'` | double scalar Default: `'-0.1061'`

Declination of the central body spin axis at J2000 (2451545.0 JD, 2000 Jan 1 12:00:00 TT), specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbDec` Type: character vector Values: `'52.88650'` | double scalar Default: `'52.88650'`

Declination rate of the central body spin axis, specified as a double scalar, in specified angle units/century.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbDecRate` Type: character vector Values: `'-0.0609'` | double scalar Default: `'-0.0609'`

Rotation angle of the central body x axis with respect to the ICRF x-axis at J2000 (2451545.0 JD, 2000 Jan 1 12:00:00 TT), specified as a double scalar, in specified angle units.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbRotAngle` Type: character vector Values: `'176.630'` | double scalar Default: `'176.630'`

Rotation rate of the central body x axis with respect to the ICRF x-axis (2451545.0 JD, 2000 Jan 1 12:00:00 UTC), specified as a double scalar, in angle units/day.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Central body spin axis source to `Dialog`.

Programmatic Use

 Block Parameter: `cbRotRate` Type: character vector Values: `'350.89198226'` | double scalar Default: `'350.89198226'`

Equatorial radius for a custom central body, specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter, set Gravitational potential model to `None`, `Point-mass`, or `Oblate ellipsoid (J2)`.

Programmatic Use

 Block Parameter: `customR` Type: character vector Values: `'3396200'` | double scalar Default: `'3396200'`

Flattening ratio for custom central body, specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Gravitational potential model to `Point-mass`, ```Oblate ellipsoid (J2)```, or `Spherical harmonics`.

Programmatic Use

 Block Parameter: `customF` Type: character vector Values: `'0.00589'` | double scalar Default: `'0.00589'`

Gravitational parameter for a custom central body, specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Gravitational potential model to `None`, `Point-mass`, or `Oblate ellipsoid (J2)`.

Programmatic Use

 Block Parameter: `customMu` Type: character vector Values: `'4.305e13'` | double scalar Default: `'4.305e13'`

Most significant or largest spherical harmonic term, which accounts for oblateness of a celestial body, specified as a double scalar.

Tunable: Yes

Dependencies

To enable this parameter:

• Set Central body to `Custom`.

• Set Gravitational potential model to `Oblate ellipsoid (J2)`.

Programmatic Use

 Block Parameter: `customJ2` Type: character vector Values: `'1.0826269e-03'` | double scalar Default: `'1.0826269e-03'`

Drag

To include atmospheric drag, select this check box.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

Programmatic Use

 Block Parameter: `useDrag` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

Source of atmospheric density value, specified as `Dialog` or `Port`.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

Programmatic Use

 Block Parameter: `atmosSrc` Type: character vector Values: `'Dialog'` | `'Port'` Default: `'Dialog'`

Atmospheric model for atmospheric drag calculation, specified as NRLMSISE-00.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Atmospheric density source parameter to `Dialog`.

Programmatic Use

 Block Parameter: `atmosModel` Type: character vector Values: `'NRLMSISE-00'` Default: `'NRLMSISE-00'`

Variation flag source, specified as `Dialog` or `Port`.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

Programmatic Use

 Block Parameter: `fluxFlagsSrc` Type: character vector Values: `'Dialog'` | `'Port'` Default: `'Dialog'`

Variation flags, specified as an array of 23 (`ones(1,23)`). You can specify one of the following values for a field. The default value for each field is `1`.

• 0.0 — Removes the effect on the output.

• 1.0 — Applies the main and the cross-term effects of that value on the output.

• 2.0 — Applies only the cross-term effect of that value on the output.

The array has these fields.

FieldDescription
`Flags(1) `

F10.7 effect on mean

`Flags(2) `

Independent of time

`Flags(3) `

Symmetrical annual

`Flags(4) `

Symmetrical semiannual

`Flags(5) `

Asymmetrical annual

`Flags(6) `

Asymmetrical semiannual

`Flags(7) `

Diurnal

`Flags(8) `

Semidiurnal

`Flags(9) `

Daily AP. If you set this field to -1, the block uses the entire matrix of magnetic index information (APH) instead of `APH(:,1)`.

`Flags(10) `

All UT, longitudinal effects

`Flags(11) `

Longitudinal

`Flags(12) `

UT and mixed UT, longitudinal

`Flags(13) `

Mixed AP, UT, longitudinal

`Flags(14) `

Terdiurnal

`Flags(15) `

Departures from diffusive equilibrium

`Flags(16) `

All exospheric temperature variations

`Flags(17) `

All variations from 120,000 meter temperature (TLB)

`Flags(18) `

All lower thermosphere (TN1) temperature variations

`Flags(19) `

All 120,000 meter gradient (S) variations

`Flags(20) `

All upper stratosphere (TN2) temperature variations

`Flags(21) `

All variations from 120,000 meter values (ZLB)

`Flags(22) `

All lower mesosphere temperature (TN3) variations

`Flags(23) `

Turbopause scale height variations

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Flags source to `Dialog`.

Programmatic Use

 Block Parameter: `fluxFlags` Type: character vector Values: `'ones(1,23)'` Default: `'ones(1,23)'`

To include anomalous oxygen in density calculations, select this check box.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

Programmatic Use

 Block Parameter: `useOxygen` Type: character vector Values: `'off'` | `'on'` Default: `'off'`

Source of drag coefficient, specified as `Dialog` or `Port`.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

Programmatic Use

 Block Parameter: `dragCoeffSrc` Type: character vector Values: `'Dialog'` | `'Source'` Default: `'Dialog'`

Spacecraft coefficient of drag used by atmospheric drag calculation, specified as a scalar or as a vector of size numSat.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Drag coefficient source parameter to `Dialog`.

Programmatic Use

 Block Parameter: `dragCoeff` Type: character vector Values: scalar | vector of size numSat Default: `'2.179'`

Source of drag area, specified as `Dialog` or `Port`.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Drag coefficient source parameter to `Dialog`.

Programmatic Use

 Block Parameter: `dragAreaSrc` Type: character vector Values: `'Dialog'` | `'Source'` Default: `'Dialog'`

Area to compute acceleration due to atmospheric drag, specified as a scalar or as a vector of size numSat. This area of the spacecraft is perpendicular to the spacecraft relative velocity.

Dependencies

To enable this parameter:

• Set the Propagation method parameter to `Numerical (high precision)`.

• Set the Central Body parameter to `Earth`.

• Select the Include atmospheric drag check box.

• Set the Drag coefficient source parameter to `Dialog`.

Programmatic Use

 Block Parameter: `dragArea` Type: character vector Values: scalar | vector of size numSat Default: `'1.0'`

Units

Parameter and port units, specified as shown here.

`Metric (m/s)`NewtonNewton-meterKilogramsKilogram m2metersmeters/secmeters/sec2m2kg/m3, some density outputs 1/m3
`Metric (km/s)`NewtonNewton-meterKilogramsKilogram m2kilometerskilometers/seckilometers/sec2m2kg/m3, some density outputs 1/m3
`Metric (km/h)`NewtonNewton-meterKilogramsKilogram m2kilometerskilometers/hourkilometers/hour2m2kg/m3, some density outputs 1/m3
`English (ft/s)`Pound-forceFoot-poundSlugsSlug ft2feetfeet/secfeet/sec2feet2lbm/ft3, some density outputs 1/ft3
`English (kts)`Pound-forceFoot-poundSlugsSlug ft2nautical mileknotsknots/secfeet2lbm/ft3, some density outputs 1/ft3

Programmatic Use

 Block Parameter: `units` Type: character vector Values: `'Metric (m/s)'` | `'Metric (km/s)'` | `'Metric (km/h)'` | `'English (ft/s)'` | `'English (kts)'` Default: `'Metric (m/s)'`

Parameter and port units for angles, specified as `Degrees` or `Radians`.

Programmatic Use

 Block Parameter: `angleUnits` Type: character vector Values: `'Degrees'` | `'Radians'` Default: `'Degrees'`

Time format for Start date/time (UTC Julian date) and output port tutc, specified as `Julian date` or `Gregorian`.

Programmatic Use

 Block Parameter: ` timeFormat` Type: character vector Values: `'Julian date'` | `'Gregorian'` Default: `'Julian date'`

expand all

References

[1] Vallado, David. Fundamentals of Astrodynamics and Applications. 4th ed. Hawthorne, CA: Microcosm Press, 2013.

[2] Vepa, Ranjan. Dynamics and Control of Autonomous Space Vehicles and Robotics. New York: Cambridge University Press, 2019.

[3] Stevens, Frank L., and Brian L. Stevens. Aircraft Control and Simulation. 2nd ed. Hoboken, NJ: John Wiley & Sons, 2003.

[4] Gottlieb, R. G. Fast Gravity, Gravity Partials, Normalized Gravity, Gravity Gradient Torque and Magnetic Field: Derivation, Code and Data. NASA Contractor Report 188243. Houston: NASA, February 1993.

[5] Konopliv, A. S., S. W. Asmar, E. Carranza, W. L. Sjogen, D. N. Yuan. "Recent Gravity Models as a Result of the Lunar Prospector Mission." Icarus 150, no. 1 (2001): 1–18.

[6] Lemoine, F. G. et al. "An Improved Solution of the Gravity Field of Mars (GMM-2B) from Mars Global Surveyor." Journal of Geophysical Research 106, no. E10 (2001): 23359–23376.

[7] Seidelmann, P. Kenneth et al. "Report of the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements: 2006." Celestial Mech Dyn Astr 98 (20017): 155–180 (2007).

[8] Standish, E. M. "JPL Planetary and Lunar Ephemerides." DE405/LE405. Interoffice memorandum. JPL IOM 312.F-98-048. August 26, 1998.

Version History

Introduced in R2021b