Explore
Known Bugs
JIRA ID | Summary | Recommendation |
GMT-585 | Multiple redundant properties/fields for epoch | P3 |
GMT-1098 | Tab key navigation fails | Appears fixed |
GMT-1346 | Add ability for user-defined parameters | Improvement |
GMT-1439 | Parameter design for multiple dependency | Improvement |
GMT-1483 | Ability to Calculate and Output Sun Vector to any point | Improvement |
GMT-1899 | Beta Angle is Off by about .003 degrees | P1 |
GMT-1933 | Earth Fixed RA changed from 0-360 to -180-180 measurement | P1 (document) |
GMT-2011 | Larger angular momentum errors in 09/15 build | P1, assign to Joel |
GMT-2318 | STM Parameters are wrong when using Coordinate System other than EarthMJ2000Eq | P1, assign to Joel |
GMT-2475 | Provide a parameter to check convergence status of a VF13 optimizer | Improvement |
GMT-2673 | User Reported: Parameter Select Dialog Box Silently Changes User's Selected Object | Needs verification |
GMT-2755 | ParameterCreateDialog does not close properly after adding string parameter on Mac | P2 |
Failing Tests
Failing tests listed as of 10/15/2012.
JIRA ID | Test | Summary | Rec. |
TBD | CbParams_Hyperbolic_2Body | Incorrect MA , OrbitPeriod | Investigate |
TBD | CSParams_Uranus1_2Body_UranusFixed | Numeric issues | Investigate |
TBD | CSParams_Saturn1_2Body_SaturnFixed | Numeric issues | Investigate |
TBD | CSParams_Pluto1_2Body_PlutoFixed | Test issues, plus numerics | Investigate |
TBD | CSParams_Neptune1_2Body_NeptuneMJ2000Ec | Test issues, plus many incorrect parameters | Investigate |
TBD | CSParams_Neptune1_2Body_NeptuneFixed | Numeric issues | Investigate |
TBD | CSParams_Hyperbolic_2Body | Numeric issues | Investigate |
TBD | CSParams_GEO_2Body | Numeric issues | Investigate |
Other Findings
JIRA ID | Summary | Rec. |
GMT-3164 | Inconsistent naming: RadApo/RadPer and VelApoapsis/RadPeriapsis | P3 |
GMT-3165 | ParameterSelectDialog is badly named | P2 |
GMT-3166 | ParameterSelectDialog string consistency issues | P3 |
GMT-3167 | ParameterSelectDialog doesn't remove item from available list once chosen | P2 |
GMT-3173 | Clarification needed on HA output range | P1 |
GMT-3205 | ParameterSelectDialog shouldn't use list box for single-parameter selection | P3 |
Requirements
To reviewers: I'm considering removing "or set" and the "(read only)/(read/write)" bits from the requirements. All of the "write" parameters should already be described on the requirement for the parent resource.
ID | Requirements |
FRR-38.1.0 | The system shall allow the user to request or set the following object properties with respect to any celestial body in FRR-16: |
FRR-38.1.1.0 | 1) Spacecraft and orbit parameters |
FRR-38.1.1.1 | 1. Altitude (read only) |
FRR-38.1.1.2 | 2. Beta angle (read only) |
FRR-38.1.1.3 | 3. C3 energy (read only) |
FRR-38.1.1.4 | 4. Eccentric anomaly (read/write) |
FRR-38.1.1.5 | 5. Eccentricity (read/write) |
FRR-38.1.1.6 | 6. Orbit energy (read only) |
FRR-38.1.1.7 | 7. Magnitude of angular momentum (read only) |
FRR-38.1.1.8 | 8. Planetodetic latitude (read only) |
FRR-38.1.1.8 | 9. Longitude (read only) |
FRR-38.1.1.10 | 10. Local sidereal time (read only) |
FRR-38.1.1.11 | 11. Mean anomaly (read/write) |
FRR-38.1.1.12 | 12. Mean hour angle (read only) |
FRR-38.1.1.13 | 13. Mean motion (read only) |
FRR-38.1.1.14 | 14. Orbit period (read only) |
FRR-38.1.1.15 | 15. Radius of apoapsis (read/write) |
FRR-38.1.1.16 | 16. Radius of periapsis (read/write) |
FRR-38.1.1.17 | 17. Magnitude of position vector (read/write) |
FRR-38.1.1.18 | 18. Semilatus rectum (read only) |
FRR-38.1.1.19 | 19. Semi-major axis (read/write) |
FRR-38.1.1.20 | 20. True anomaly (read/write) |
FRR-38.1.1.21 | 21. Velocity at apoapsis (read only) |
FRR-38.1.1.22 | 22. Velocity at periapsis (read only) |
FRR-38.1.1.23 | 23. Hyperbolic anomaly (read/write) |
FRR-38.1.1.24 | 24. Apoapsis crossing indicator (read only) |
FRR-38.1.1.25 | 25. Periapsis crossing indicator (read only) |
FRR-38.2.0 | The system shall allow the user to request or set the following object properties with respect to any coordinate system in FRR-35: |
FRR-38.2.1.0 | 1) Spacecraft and orbit parameters |
FRR-38.2.1.1 | 1. Argument of periapsis (read/write) |
FRR-38.2.1.2 | 2. Azimuth (read/write) |
FRR-38.2.1.3 | 3. B dot T (read only) |
FRR-38.2.1.4 | 4. B dot R (read only) |
FRR-38.2.1.5 | 5. B vector angle (read only) |
FRR-38.2.1.6 | 6. B vector magnitude (read only) |
FRR-38.2.1.7 | 7. Declination (read/write) |
FRR-38.2.1.8 | 8. Declination of velocity (read/write) |
FRR-38.2.1.9 | 9. Flight path angle (read/write) |
(delete) | |
FRR-38.2.1.11 | 11. Components of angular momentum (read only) |
FRR-38.2.1.12 | 12. Inclination (read/write) |
FRR-38.2.1.13 | 13. Orbit state transition matrix (read only) |
FRR-38.2.1.14 | 14. 3x3 partitions of Orbit STM (read only) |
FRR-38.2.1.15 | 15. Right ascension (read/write) |
FRR-38.2.1.16 | 16. Right ascension of the ascending node (read/write) |
FRR-38.2.1.17 | 17. Right ascension of velocity (read/write) |
FRR-38.2.1.18 | 18. Magnitude of velocity (read/write) |
FRR-38.2.1.19 | 19. Components of Cartesian velocity (read/write) |
FRR-38.2.1.20 | 20. Components of Cartesian position (read/write) |
FRR-38.2.1.21 | 21. Right ascension of outgoing hyperbolic asymptote (read only) |
FRR-38.2.1.22 | 22. Declination of outgoing hyperbolic asymptote (read only) |
FRR-38.3.0 | The system shall allow the user to request or set the following object properties: |
FRR-38.3.1.0 | 1) Spacecraft and orbit parameters |
FRR-38.3.1.3 | 3. Components of angular velocity (read/write) |
FRR-38.3.1.4 | 4. Drag coefficient (read/write) |
FRR-38.3.1.5 | 5. Reflectivity coefficient (read/write) |
FRR-38.3.1.6 | 6. Components of attitude direction cosine matrix (read/write) |
FRR-38.3.1.7 | 7. Drag area (read/write) |
FRR-38.3.1.8 | 8. Dry mass (read/write) |
FRR-38.3.1.9 | 9. Elapsed days (read only) |
FRR-38.3.1.10 | 10. Elapsed seconds (read only) |
(delete) | |
(delete) | |
FRR-38.3.1.13 | 13. Components of attitude quaternion (read only) |
FRR-38.3.1.14 | 14. SRP area (read/write) |
FRR-38.3.1.15 | 15. Epoch in TAI modified Julian (read/write) |
FRR-38.3.1.16 | 16. Epoch in TAI Gregorian (read/write) |
FRR-38.3.1.19 | 19. Epoch in TDB modified Julian (read/write) |
FRR-38.3.1.20 | 20. Epoch in TDB Gregorian (read/write) |
FRR-38.3.1.21 | 21. Epoch in TT modified Julian (read/write) |
FRR-38.3.1.22 | 22. Epoch in TT Gregorian (read/write) |
FRR-38.3.1.23 | 23. Epoch in UTC modified Julian (read/write) |
FRR-38.3.1.24 | 24. Epoch in UTC Gregorian (read/write) |
FRR-38.3.1.25 | 25. Total mass (read only) |
FRR-38.3.1.26 | 26. Modified Rodrigues parameters (read/write) |
FRR-38.3.1.27 | 27. Euler angles (read/write) |
FRR-38.3.1.28 | 28. Euler angle rates (read/write) |
FRR-38.3.1.29 | 29. Epoch in A.1 modified Julian (read/write) |
FRR-38.3.1.30 | 30. Epoch in A.1 Gregorian (read/write) |
FRR-38.3.1.31 | 31. Attitude quaternion (read/write) |
FRR-38.3.2.0 | 2) Impulsive burn parameters |
FRR-38.3.2.1 | 1. Thrust vector element 1 (read/write) |
FRR-38.3.2.2 | 2. Thrust vector element 2 (read/write) |
FRR-38.3.2.3 | 3. Thrust vector element 3 (read/write) |
(delete) | |
(delete) | |
(delete) | |
FRR-38.3.3.0 | 3) Tank parameters |
FRR-38.3.3.1 | 1. Pressure (read/write) |
FRR-38.3.3.2 | 2. Volume (read/write) |
FRR-38.3.3.3 | 3. Fuel density (read/write) |
FRR-38.3.3.4 | 4. Fuel mass (read/write) |
FRR-38.3.3.5 | 5. Temperature (read/write) |
FRR-38.3.3.6 | 6. Reference temperature (read/write) |
FRR-38.3.4.0 | 4) Thruster parameters |
FRR-38.3.4.1 | 1. Duty cycle (read/write) |
FRR-38.3.4.2 | 2. Thrust scale factor (read/write) |
FRR-38.3.4.3 | 3. Gravitational acceleration for thrust equation (read/write) |
FRR-38.3.4.4 | 4. Thrust coefficients (read/write) |
FRR-38.3.4.5 | 5. Isp coefficients (read/write) |
FRR-38.3.4.6 | 6. Components of thrust direction (read/write) |
Interface/Functional Spec
Overview
Data property available for use by commands
Description
Parameters are named resource properties that can be used to obtain data for use by Mission Sequence commands or by output resources. Some parameters, such as the Altitude parameter of Spacecraft, are calculated values that can only be used to retrieve data. They cannot be set directly. Others, such as the Element1 parameter of ImpulsiveBurn, share the same name as a resource field and can be used both to set data and retrieve it. Parameters are distinguished from resource fields by their extra functionality: fields are static resource properties that are usually set in initialization (or in the GUI Resources tree), while parameters can be calculated on the fly and used in plots, reports, and mathematical expressions.
Parameters are classified as one of four types: central-body-dependent parameters, coordinate-system-dependent parameters, attached-hardware parameters, and standalone parameters. Standalone parameters are the simplest type, in that they have no dependencies. The ElapsedSecs parameter of Spacecraft is an example of this; it is simply referenced as Spacecraft.ElapsedSecs
.
Central-body-dependent parameters, as the name suggests, have a value that is dependent on the chosen celestial body. The Altitude parameter of Spacecraft is an example of this. To reference this parameter, you must specify a central body, such as Spacecraft.Mars.Altitude
. Any built-in central body or user-defined Asteroid, Comet, Moon, or Planet is valid as a dependency. If the dependency is omitted, Earth is assumed.
Likewise, coordinate-system-dependent parameters have a value that is dependent on the chosen coordinate system. The DEC parameter of Spacecraft is an example of this. To reference this parameter, you must specify the name of a CoordinateSystem resource, such as Spacecraft.EarthFixed.DEC
. Any default or user-defined CoordinateSystem resource is valid as a dependency. If the dependency is omitted, EarthMJ2000Eq is assumed.
Attached-hardware parameters have no dependencies, but are themselves dependent on being attached to a Spacecraft. FuelTank and Thruster parameters are examples of this. The FuelMass parameter of FuelTank cannot be referenced without first attaching the FuelTank to a Spacecraft. Then, the parameter can be referenced as: Spacecraft.FuelTank.FuelMass
.
The individual parameters are resource-specific, and are documented along with the their parent resources. The GUI, however, has a parameter selection interface that is common to all parameters. This interface is documented in GUI, below.
See Also: Script Language, FuelTank, ImpulsiveBurn, Spacecraft, Thruster
GUI
Parameters can be used as input in several places throughout GMAT, such as the ReportFile and XYPlot resources and the If/Else, Propagate, and Report commands. In the GUI, all of these use a common interface called the ParameterSelectDialog that allows for interactive parameter selection. A basic ParameterSelectDialog window looks like the following:
The ParameterSelectDialog window is used to build a parameter, along with any dependencies, for use in a command or resource. Some resources and commands have different requirements for the types of parameters that can be used, so the ParameterSelectDialog can take slightly different forms, depending on where it's used. This section will describe the generic interface, then mention any resource- or command-specific exceptions.
General Usage
The first step in choosing a parameter is to select the object (or resource) type from the Object Type list in the upper left. Five types can appear in this list: Spacecraft, ImpulsiveBurn, Variable, Array, and String.
Once you've selected a type, The Object List box is populated with all existing resources of that type. Use this list to choose the specific resource you'd like to reference.
If the Spacecraft type is selected, the Attached Hardware List appears below the Object List. This list displays any hardware (such as FuelTank resources) attached to the selected Spacecraft. If the Array type is selected, Row and Col boxes appear. Use these to specify a row and column to select an individual array element, or check Select Entire Object to choose the entire array.
Once a resource is selected, the Object Properties list is populated with all available parameters provided by that resource. Some resources, such as instances of Variable or Array, are themselves parameters, so this list remains empty.
Parameters with different dependency types are commingled in the Object Properties list. When you select one, the appropriate dependency (if any) appears below the list. For example, after selecting the Spacecraft AOP parameter, a Coordinate System list appears. After selecting the Spacecraft Apoapsis parameter, a Central Body list appears. And after selecting the Spacecraft Cd parameter, no dependency list appears. To select a range of parameters from the Object Properties list, hold down the Shift key while selecting the second endpoint of the range. To select multiple individual parameters, hold down the Ctrl key while making each selection.
To select a parameter, select the appropriate Object Type, the specific resource from the Object List or Attached Hardware List, the desired parameter from the Object Properties list, and the required dependency, and add it to the Selected Value(s) list on the right. There are six buttons available to control this list:
- UP: Move the selected item in the Selected Value(s) list up one position (if allowed).
- DN: Move the selected item in the Selected Value(s) list down one position (if allowed).
- ->: Add the selected item in the Object Properties list to the Selected Value(s) list.
- <-: Remove the selected item in the Selected Value(s) list.
- =>: Add all items to the Selected Value(s) list.
- <=: Remove all items from the Selected Value(s) list.
When finished, the Selected Value(s) list contains the final selected parameters. Click OK to accept the selection.
Special Considerations
Some resources and commands (such as the Propagate command Parameter argument) only accept a single parameter as input; in this context the ParameterSelectDialog only allows one parameter in the Selected Value(s) list and does not allow use of the UP, DN, and => buttons.
In some instances (such as in the Vary command), only parameters that are also fields (and so can be set in the Mission Sequence) can be used. In this case only the allowed parameters will be shown in the Object Properties list.
In the Propagate command Parameter argument, only parameters of Spacecraft can be used. In this case only Spacecraft will be shown in the Object Type list.
Parameters
To Reviewer: These tables will be merged into the parent reference pages and labeled as "Field" or "Parameter". For existing fields, the description already in the spec will be used instead of the description below. Each section below will be linked to the parent reference page. |
---|
To Reviewer: The "Tests" field for each parameter is part of the test procedures for this spec. It identifies the feature responsible for testing that parameter. This field will not be migrated to the final doc.
To Technical Writer: The "pencil" icon in the following tables is from http://www.famfamfam.com/lab/icons/silk/. They're free to use, but we need to credit them. |
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Spacecraft
Parameter | Units | Description | ||
ElapsedSecs | N | Y | s | Spacecraft Data Type: Real Number |
ElapsedDays | N | Y | d | Spacecraft Data Type: Real Number |
A1ModJulian | Y | Y | d | Spacecraft orbit epoch in the A.1 system and the Modified Julian format. Data Type: Real Number |
A1Gregorian | Y | N | N/A | Spacecraft orbit epoch in the A.1 system and the Gregorian format. Data Type: String |
TAIModJulian | Y | Y | d | Spacecraft orbit epoch in the TAI system and the Modified Julian format. Data Type: Real Number |
TAIGregorian | Y | N | N/A | The spacecraft orbit epoch in the TAI system and the Gregorian format. Data Type: String |
TTModJulian | Y | Y | d | The spacecraft orbit epoch in the TT system and the Modified Julian format. Data Type: Real Number |
TTGregorian | Y | N | N/A | Spacecraft orbit epoch in the TT system and the Gregorian format. Data Type: String |
TDBModJulian | Y | Y | d | Spacecraft orbit epoch in the TDB system and the Modified Julian format. Data Type: Real Number |
TDBGregorian | Y | N | N/A | Spacecraft orbit epoch in the TDB system and the Gregorian format. Data Type: String |
UTCModJulian | Y | Y | d | Spacecraft orbit epoch in the UTC system and the Modified Julian format. Data Type: Real Number |
UTCGregorian | Y | N | N/A | Spacecraft orbit epoch in the UTC system and the Gregorian format. Data Type: String |
X | Y | Y | km | Cartesian x-component of the spacecraft position. Data Type: Real Number |
Y | Y | Y | km | Cartesian y-component of the spacecraft position. Data Type: Real Number |
Z | Y | Y | km | Cartesian z-component of the spacecraft position. Data Type: Real Number |
VX | Y | Y | km/s | Cartesian x-component of the spacecraft velocity. Data Type: Real Number |
VY | Y | Y | km/s | Cartesian y-component of the spacecraft velocity. Data Type: Real Number |
VZ | Y | Y | km/s | Cartesian z-component of the spacecraft velocity. Data Type: Real Number |
SMA | Y | Y | km | Orbit semi-major axis. Data Type: Real Number |
ECC | Y | Y | N/A | Orbit eccentricity. Data Type: Real Number |
INC | Y | Y | ° | Orbit inclination. Data Type: Real Number Tests: FRR-1 |
RAAN | Y | Y | ° | Orbit right ascension of the ascending node. Data Type: Real Number |
AOP | Y | Y | ° | Orbit argument of periapsis. Data Type: Real Number |
TA | Y | Y | ° | True anomaly. Data Type: Real Number |
MA | Y | Y | ° | Mean anomaly. Data Type: Real Number |
EA | Y | Y | ° | Eccentric anomaly. Data Type: Real Number |
HA | Y | Y | ° | Hyperbolic anomaly. Data Type: Real Number |
MM | N | Y | rad/s | Mean motion. Data Type: Real Number |
VelApoapsis | N | Y | km/s | Scalar velocity at apoapsis. Data Type: Real Number |
VelPeriapsis | N | Y | km/s | Scalar velocity at periapsis. Data Type: Real Number |
Apoapsis | N | Y | N/A | A parameter that equals zero when the spacecraft is at orbit apoapsis. This parameter is intended to be used as a stopping condition in the Propagate command. Data Type: Real Number |
Periapsis | N | Y | N/A | A parameter that equals zero when the spacecraft is at orbit periapsis. This parameter is intended to be used as a stopping condition in the Propagate command. Data Type: Real Number |
OrbitPeriod | N | Y | s | Osculating orbit period. Data Type: Real Number |
RadApo | Y | Y | km | Radius of apoapsis. Data Type: Real Number Dependency: Central Body |
RadPer | Y | Y | km | Radius of periapsis. Data Type: Real Number |
C3Energy | N | Y | MJ/kg (km^{2}/s^{2}) | C_{3} (characteristic) energy. Data Type: Real Number |
Energy | N | Y | MJ/kg (km^{2}/s^{2}) | Specific orbital energy. Data Type: Real Number |
RMAG | Y | Y | km | Magnitude of the orbital position vector. Data Type: Real Number |
RA | Y | Y | ° | Right ascension of the orbital position. Data Type: Real Number |
DEC | Y | Y | ° | Declination of the orbital position. Data Type: Real Number |
VMAG | Y | Y | km/s | Magnitude of the orbital velocity vector. Data Type: Real Number |
RAV | Y | Y | ° | Right ascension of orbital velocity. Data Type: Real Number |
DECV | Y | Y | ° | Declination of orbital velocity. Data Type: Real Number |
AZI | Y | Y | ° | Orbital velocity azimuth. Data Type: Real Number |
FPA | Y | Y | ° | Orbital flight path angle. Data Type: Real Number |
SemilatusRectum | N | Y | km | Semilatus rectum of the osculating orbit. Data Type: Real Number |
HMAG | N | Y | km^{2}/s | Magnitude of the angular momentum vector. Data Type: Real Number |
HX | N | Y | km^{2}/s | X component of the angular momentum vector. Data Type: Real Number |
HY | N | Y | km^{2}/s | Y component of the angular momentum vector. Data Type: Real Number |
HZ | N | Y | km^{2}/s | Z component of the angular momentum vector. Data Type: Real Number |
DLA | N | Y | ° | Declination of the outgoing hyperbolic asymptote. Data Type: Real Number |
RLA | N | Y | ° | Right ascension of the outgoing hyperbolic asymptote. Data Type: Real Number |
Altitude | N | Y | km | Distance to the plane tangent to the surface of the specified celestial body at the sub-satellite point. GMAT assumes the body is an ellipsoid. Data Type: Real Number |
MHA | N | Y | ° | Greenwich hour angle. Data Type: Real Number |
Longitude | N | Y | ° | Planetodetic longitude. Data Type: Real Number |
Latitude | N | Y | ° | Planetodetic latitude. Data Type: Real Number |
LST | N | Y | ° | Local sidereal time. Data Type: Real Number |
BetaAngle | N | Y | ° | Beta angle (or phase angle) between the orbit normal vector and the vector from the celestial body to the sun. Data Type: Real Number |
BdotT | N | Y | km | B-plane B·T magnitude. Data Type: Real Number |
BdotR | N | Y | km | B-plane B·R magnitude. Data Type: Real Number |
BVectorMag | N | Y | km | B-plane B vector magnitude. Data Type: Real Number |
BVectorAngle | N | Y | ° | B-plane angle between the B vector and the T unit vector. Data Type: Real Number |
DCM11 | Y | Y | (None) | Element (1,1) of the attitude direction cosine matrix. Data Type: Real Number |
DCM12 | Y | Y | (None) | Element (1,2) of the attitude direction cosine matrix. Data Type: Real Number |
DCM13 | Y | Y | (None) | Element (1,3) of the attitude direction cosine matrix. Data Type: Real Number |
DCM21 | Y | Y | (None) | Element (2,1) of the attitude direction cosine matrix. Data Type: Real Number |
DCM22 | Y | Y | (None) | Element (2,2) of the attitude direction cosine matrix. Data Type: Real Number |
DCM23 | Y | Y | (None) | Element (2,3) of the attitude direction cosine matrix. Data Type: Real Number |
DCM31 | Y | Y | (None) | Element (3,1) of the attitude direction cosine matrix. Data Type: Real Number |
DCM32 | Y | Y | (None) | Element (3,2) of the attitude direction cosine matrix. Data Type: Real Number |
DCM33 | Y | Y | (None) | Element (3,3) of the attitude direction cosine matrix. Data Type: Real Number |
EulerAngle1 | Y | Y | ° | Attitude Euler angle 1. Data Type: Real Number |
EulerAngle2 | Y | Y | ° | Attitude Euler angle 2. Data Type: Real Number |
EulerAngle3 | Y | Y | ° | Attitude Euler angle 3. Data Type: Real Number |
MRP1 | Y | Y | (None) | Attitude modified Rodrigues parameter 1. Data Type: Real Number |
MRP2 | Y | Y | (None) | Attitude modified Rodrigues parameter 2. Data Type: Real Number |
MRP3 | Y | Y | (None) | Attitude modified Rodrigues parameter 3. Data Type: Real Number |
Q1 | N | Y | (None) | Attitude quaternion element 1 (a). Data Type: Real Number |
Q2 | N | Y | (None) | Attitude quaternion element 2 (b). Data Type: Real Number |
Q3 | N | Y | (None) | Attitude quaternion element 3 (c). Data Type: Real Number |
Q4 | N | Y | (None) | Attitude quaternion element 4 (d). Data Type: Real Number |
Quaternion | Y | N | (None) | Attitude quaternion. Data Type: Array (1×4) |
AngularVelocityX | Y | Y | °/s | X component of the attitude angular velocity vector. Data Type: Real Number |
AngularVelocityY | Y | Y | °/s | Y component of the attitude angular velocity vector. Data Type: Real Number |
AngularVelocityZ | Y | Y | °/s | Z component of the attitude angular velocity vector. Data Type: Real Number |
EulerAngleRate1 | Y | Y | °/s | Rate of attitude Euler angle 1. Data Type: Real Number |
EulerAngleRate2 | Y | Y | °/s | Rate of attitude Euler angle 2. Data Type: Real Number |
EulerAngleRate3 | Y | Y | °/s | Rate of attitude Euler angle 3. Data Type: Real Number |
DryMass | Y | Y | kg | Dry mass (without propellant). Data Type: Real Number |
Cd | Y | Y | (None) | Coefficient of drag. Data Type: Real Number |
Cr | Y | Y | (None) | Coefficient of reflectivity. Data Type: Real Number |
DragArea | Y | Y | m^{2} | Area used to compute acceleration due to atmospheric drag. Data Type: Real Number |
SRPArea | Y | Y | m^{2} | Area used to compute acceleration due to solar radiation pressure. Data Type: Real Number |
TotalMass | N | Y | kg | Total mass, including fuel mass from attached Fuel Tank resources. Data Type: Real Number |
OrbitSTM | N | N | (None) | State transition matrix. Data Type: Array (6×6) |
OrbitSTMA | N | N | (None) | Upper-left quadrant of the state transition matrix. Data Type: Array (3×3) |
OrbitSTMB | N | N | (None) | Upper-right quadrant of the state transition matrix. Data Type: Array (3×3) |
OrbitSTMC | N | N | (None) | Lower-left quadrant of the state transition matrix. Data Type: Array (3×3) |
OrbitSTMD | N | N | (None) | Lower-right quadrant of the state transition matrix. Data Type: Array (3×3) |
FuelTank
Parameter | Units | Description | ||
FuelMass | Y | Y | kg | Mass of fuel in the tank. Data Type: Real Number |
Volume | Y | Y | m^{3} | Volume of the tank. GMAT checks to ensure that the input volume of the tank is larger than the calculated volume of fuel loaded in the tank and throws an exception in the case that the calculated fuel volume is larger than the input tank volume. Data Type: Real Number |
FuelDensity | Y | Y | kg/m^{3} | Density of the fuel. Data Type: Real Number |
Pressure | Y | Y | kPa | Pressure in the tank. Data Type: Real Number |
Temperature | Y | Y | °C | Temperature of the fuel and ullage in the tank. GMAT currently assumes ullage and fuel are always at the same temperature. Data Type: Real Number |
RefTemperature | Y | Y | °C | The temperature of the tank when fuel was loaded. Data Type: Real Number |
Thruster
Parameter | Units | Description | ||
DutyCycle | Y | Y | (None) | Fraction of time that the thrusters are on during a maneuver. The thrust applied to the spacecraft is scaled by this amount. Note that this scale factor also affects mass flow rate. Data Type: Real Number |
ThrustScaleFactor | Y | Y | (None) | Scale factor that is multiplied by the thrust vector, for a given thruster, before the thrust vector is added into the total acceleration. Note that the value of this scale factor does not affect the mass flow rate. Data Type: Real Number |
GravitationalAccel | Y | Y | m/s^{2} | Value of the gravitational acceleration used for the FuelTank/Thruster calculations. Data Type: Real Number |
C1 | Y | Y | N | Thrust coefficient C_{1}. Data Type: Real Number |
C2 | Y | Y | N/kPa | Thrust coefficient C_{2}. Data Type: Real Number |
C3 | Y | Y | N | Thrust coefficient C_{3}. Data Type: Real Number |
C4 | Y | Y | N/kPa | Thrust coefficient C_{4}. Data Type: Real Number |
C5 | Y | Y | N/kPa^{2} | Thrust coefficient C_{5}. Data Type: Real Number |
C6 | Y | Y | N/kPa^{C7} | Thrust coefficient C_{6}. Data Type: Real Number |
C7 | Y | Y | (None) | Thrust coefficient C_{7}. Data Type: Real Number |
C8 | Y | Y | N/kPa^{C9} | Thrust coefficient C_{8}. Data Type: Real Number |
C9 | Y | Y | (None) | Thrust coefficient C_{9}. Data Type: Real Number |
C10 | Y | Y | N/kPa^{C11} | Thrust coefficient C_{10}. Data Type: Real Number |
C11 | Y | Y | (None) | Thrust coefficient C_{11}. Data Type: Real Number |
C12 | Y | Y | N | Thrust coefficient C_{12}. Data Type: Real Number |
C13 | Y | Y | (None) | Thrust coefficient C_{13}. Data Type: Real Number |
C14 | Y | Y | 1/kPa | Thrust coefficient C_{14}. Data Type: Real Number |
C15 | Y | Y | (None) | Thrust coefficient C_{15}. Data Type: Real Number |
C16 | Y | Y | 1/kPa | Thrust coefficient C_{16}. Data Type: Real Number |
K1 | Y | Y | s | I_{sp} coefficient K_{1}. Data Type: Real Number |
K2 | Y | Y | s/kPa | I_{sp} coefficient K_{2}. Data Type: Real Number |
K3 | Y | Y | s | I_{sp} coefficient K_{3}. Data Type: Real Number |
K4 | Y | Y | s/kPa | I_{sp} coefficient K_{4}. Data Type: Real Number |
K5 | Y | Y | s/kPa^{2} | I_{sp} coefficient K_{5}. Data Type: Real Number |
K6 | Y | Y | s/kPa^{C7} | I_{sp} coefficient K_{6}. Data Type: Real Number |
K7 | Y | Y | (None) | I_{sp} coefficient K_{7}. Data Type: Real Number |
K8 | Y | Y | s/kPa^{C9} | I_{sp} coefficient K_{8}. Data Type: Real Number |
K9 | Y | Y | (None) | I_{sp} coefficient K_{9}. Data Type: Real Number |
K10 | Y | Y | s/kPa^{C11} | I_{sp} coefficient K_{10}. Data Type: Real Number |
K11 | Y | Y | (None) | I_{sp} coefficient K_{11}. Data Type: Real Number |
K12 | Y | Y | s | I_{sp} coefficient K_{12}. Data Type: Real Number |
K13 | Y | Y | (None) | I_{sp} coefficient K_{13}. Data Type: Real Number |
K14 | Y | Y | 1/kPa | I_{sp} coefficient K_{14}. Data Type: Real Number |
K15 | Y | Y | (None) | I_{sp} coefficient K_{15}. Data Type: Real Number |
K16 | Y | Y | 1/kPa | I_{sp} coefficient K_{16}. Data Type: Real Number |
ThrustDirection1 | Y | Y | (None) | ThrustDirection1, divided by the RSS of the three direction components, forms the x component of the spacecraft thrust vector direction. Data Type: Real Number |
ThrustDirection2 | Y | Y | (None) | ThrustDirection2, divided by the RSS of the three direction components, forms the y component of the spacecraft thrust vector direction. Data Type: Real Number |
ThrustDirection3 | Y | Y | (None) | ThrustDirection3, divided by the RSS of the three direction components, forms the z component of the spacecraft thrust vector direction. Data Type: Real Number |
ImpulsiveBurn
Parameter | Units | Description | ||
Element1 | Y | Y | (None) | X-component of the applied impulsive burn (delta-V). Data Type: Real Number |
Element2 | Y | Y | (None) | Y-component of the applied impulsive burn (delta-V). Data Type: Real Number |
Element3 | Y | Y | (None) | Z-component of the applied impulsive burn (delta-V). Data Type: Real Number |
V | Y | Y | (None) | Deprecated. Velocity component of the applied impulsive burn (delta-V). Data Type: Real Number |
N | Y | Y | (None) | Deprecated. Normal component of the applied impulsive burn (delta-V). Data Type: Real Number |
B | Y | Y | (None) | Deprecated. Binormal component of the applied impulsive burn (delta-V). Data Type: Real Number |
Array, String, Variable
Array, String, and Variable resources are themselves parameters, and can be used as any other parameter would. All of these are writable parameters, though only Variable resources and individual elements of Array resources can be plotted.
Examples
Using parameters in the Mission Sequence:
Create Spacecraft aSat Create Propagator aProp Create ReportFile aReport BeginMissionSequence % propagate for 100 steps For i=1:100 Propagate aProp(aSat) % write four parameters (one standalone, three coordinate-system-dependent) to a file Report aReport aSat.TAIGregorian aSat.EarthFixed.X aSat.EarthFixed.Y aSat.EarthFixed.Z EndFor
Using parameters as plot data:
Create Spacecraft aSat Create Propagator aProp Create XYPlot aPlot aPlot.XVariable = aSat.TAIModJulian aPlot.YVariables = {aSat.Earth.Altitude, aSat.Earth.ECC} BeginMissionSequence % propagate for 100 steps For i=1:100 Propagate aProp(aSat) EndFor
Using parameters as stopping conditions:
Create Spacecraft aSat aSat.SMA = 6678 Create ForceModel anFM anFM.Drag.AtmosphereModel = MSISE90 Create Propagator aProp aProp.FM = anFM BeginMissionSequence Propagate aProp(aSat) {aSat.Earth.Altitude = 100, aSat.ElapsedDays = 365}
Test Procedures
Assumptions
The purpose of parameter testing is as follows:
- To make sure the parameter infrastructure works
- changing dependencies has an effect
- default dependency is used when omitted
- correct units and data types are used
- To test math for calculated parameters
For parameters that are also fields, we can assume that the math is being tested in the tests for the parent resource. For example, there is no need to thoroughly test Spacecraft.X here, since that is captured in the FRR-1 state conversion tests. In the tables above, each parameter is labeled with a "Tests" field that identifies the requirement responsible for testing it. If FRR-38 is listed, it will be tested as a part of this test plan.
Existing Tests
The existing tests have very high tolerances across the board; this needs further investigation and data-matching.
Priority | Status | Name | Summary |
CBParams_Earth_* | Central-body parameters at Earth in LEO orbit | ||
CbParams_*_2Body | All central-body parameters at central body of several orbit types | ||
CSParams_*_2Body_* | All coordinate-system parameters at several coordinate systems with central body as origin, in several orbit types | ||
HyperbolicAnomaly_Valid | Spacecraft.HA | ||
ImpulsiveBurnParams_VNB_Elements | ImpulsiveBurn.Element* params, using VNB CS | ||
ReportSatHardware | Set then get of all Thruster and FuelTank params | ||
SelectedHyperbolicParams_* | Hyperbolic asymptote parameters (B-plane, RLA, DLA) for two Earth-centered coordinate systems | ||
SpacecraftElapsedTimeParams | Spacecraft.ElapsedSecs , Spacecraft.ElapsedDays | ||
SpacecraftPhysicalParams | Spacecraft physical parameters | ||
TankParams | Report all FuelTank parameters |
Recommended Additional Tests
Nominal Tests
- Bold items are used by existing parameter tests
Orbit types:
- ISS
- GEO
- Molniya
- Hyperbolic
- Jupiter-centered
- Mars-centered
- Mercury-centered
- Moon-centered
- Neptune-centered
- Pluto-centered
- Saturn-centered
- Uranus-centered
- Venus-centered
- Earth-Sun L2
- Mars Transfer
Central bodies:
- (default)
- CB of SC coordinate system
- all planets
- Moon
- Sun
- SSB
- User planet
- User asteroid
- User comet
- User Moon
- User barycenter
- User libration point
Coordinate systems
- (default)
- origin at orbit central body
- origin at all other bodies (see list above)
- MJ2000Eq
- MJ2000Ec
- Fixed
- TOEEq
- TOEEc
- MOEEq
- MOEEc
- TODEq
- TODEc
- MODEq
- MODEc
- EarthMoonRotating
- MarsEquator
- LunaInertial
- GSE
- GSM
- Topocentric
- ICRF
- ITRF
- BSS
Priority | Status | Summary |
Report all orbit params with all orbit/dependency combinations (ISS orbit with all CSs/CBs, others with a few each) | ||
Set all settable params using default and explicit values | ||
Report all standalone params | ||
Plot all plottable params |
Edge/Corner/Stres
Priority | Status | Summary |
Unique Validation
Priority | Status | Summary |
Unique Mode Tests
Priority | Status | Summary |
Unique GUI Tests
These are tests that are unique to the GUI interface for this feature that are not covered by the standard GUI test template and procedures.
Priority | Status | Summary |
The orbital argument of periapsis expressed in the coordinate system chosen in the CoordinateSystem field.
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