Set options for the HPOP force model
HPOP <ObjectPath> Force {ForceModel} <ModelParameters>
The HPOP Force command enables you to set force model options for propagating a satellite's or missile's orbit using the High-Precision Orbit Propagator (HPOP) module.
To set options for the HPOP Drag force model see the HPOP Drag command.
This command is valid for Satellites and Missiles.
{ForceModel} and <ModelParameters> are:
| {ForceModel} | <ModelParameters> | Description |
|---|---|---|
| Gravity | "<FilePath>" <MaxDegreeValue> <MaxOrderValue> | <MaxDegreeValue> and <MaxOrderValue> are real numbers between 0.0 and 1000.0. <MaxOrderValue> must be less than or equal to <MaxDegreeValue>. Also, the values must be less than the Maximum Degree and Maximum Order in the selected Gravity File. |
| ThirdBodyGravity | <CentralBodyName> {On | Off} {GravSource} [<UserGravValue>] | Valid values for {GravSource} are Internal, FromCB, JPLDEFile or User. If {GravSource} is User, a real number greater than 0.0 representing the <UserGravValue> must be entered. |
| SRP | {On | Off} [{Options}] | Set Solar Radiation Pressure options. If On is entered then also enter any or all of the {Options} described in the table below. If Off is entered, no {Options} should be entered. |
| SolarRad | {SolarRadState} [<Coeff> <AreaMassRatio>] [ShadowModel {ModelType}] [BoundaryMitigation {On | Off}] |
Note: This option is deprecated in STK 9, please use the SRP option. {SolRadState} can be On or Off. If {SolRadState} is On, also enter a real number between -100.0 and 100.0 for <Coeff> and a real number between 0.0 and 9999.00, specified in m^2/kg, for <AreaMassRatio>. Valid values for ShadowModel {ModelType}] are None, Cylindrical or DualCone. |
| SolidTides | {Full | Permanent | Off}
[IncTimeDep {On | Off}] [MinAmplitude <Amplitude>] [TruncateSolidTides {On | Off}] |
If SolidTides Off is entered than no
other parameters should be entered.
Enter Permanent to only consider the permanent tide (the time-independent part of the tide contribution); enter Full to consider the full solid tide model <Amplitude> is entered in meters and is between 0.0 and 1.0. |
| OceanTides | {On | Off}
[MaxDegree <MaxDegreeValue>] [MaxOrder <MaxOrderValue>] [MinAmplitude <Amplitude>] |
If OceanTides Off is entered than no other parameters should be entered. <MaxDegreeValue> is an integer between 2 and 30. <MaxOrderValue> is an integer between 0 and 30. <Amplitude> is entered in meters and is between 0.0 and 1.0. |
| RadiationPressure | Enter at least one of the following
options:
|
<CoeffValue> is a real number between -100 and 100.0 <AMRValue> is a real number between 0.0 and 9999.0, and is entered in m^2/kg "<FilePath>" is the Ground Reflection Model File. |
| EclipsingBodies | {Add | Remove} <CBName> | Add and Remove central bodies from the Force Model Eclipsing Bodies list. Multiple entries of {Add | Remove} <CBName> can be included on one command line. |
| UseGravitySecularVariations | {On | Off} | Specify whether to include secular
variations in gravity coefficients.
If you are using the EGM96 or EGM2008 gravity model, select this option to use the evolution parameters for C20, C21, and S21 in accordance with IERS Technical Note 32, IERS Conventions (2003). |
The following table describes the SRP {Options}:
| SRP {Options} | Description |
|---|---|
| Model {ModelName} <Parameters> | Spherical <Cr> <AMRatio>
For the Spherical model enter the solar radiation pressure coefficient, which should be between -100.0 and 100.0. The area/mass ratio should be between 0 and 9999.0 |
| {GPSModel} <K1> <K2>
Enter a GPS model name, these values are case-sensitive: GPS_BlkIIA_AeroT20, GPS_BlkIIR_AeroT30, GPS_BlkIIA_GSPM04ae, GPS_BlkIIR_GSPM04ae, GPS_BlkIIA_GSPM04a, GPS_BlkIIR_GSPM04a. The satellite must be on Earth in order to use one of these models. <K1> is a value between 0.0 and 1.0E30; <K2> is a value between -1.0E30 and 1.0E30 |
|
| ReflectionPlugin <Name>
If you have a Reflection plugin registered, then enter the <Name> to use this model. |
|
| ShadowModel {None | Cylindrical | DualCone} | Specify the type of shadow to be used in determining the lighting condition for the satellite. |
| BoundaryMitigation {On | Off} | Enter On to correct the state of the satellite after crossing a shadow boundary for errors that may have been introduced by the sudden change in the SRP which occurred during the integration step. The default is Off. |
Note: For this command to be valid, the satellite or missile must already be defined as using the HPOP propagator.
To turn On the solar radiation pressure model for the ERS1 satellite with a coefficient of 3.2 and area mass ratio of 221.0:
HPOP */Satellite/ERS1 Force SRP On Model Spherical 3.2 221.0
To set the third body gravity model to use Venus, and to get the gravitational value from the Venus central body file:
HPOP */Satellite/Satellite1 Force ThirdBodyGravity Venus On FromCB
To set the third body gravity model to not use the Sun's gravitational pull:
HPOP */Satellite/Satellite1 Force ThirdBodyGravity Sun Off
To set the third body gravity model to use Mars, and to use 1234567.89 for the gravitational value:
HPOP */Satellite/Satellite1 Force ThirdBodyGravity Mercury On User 1234567.89
To have the Earth Gravity file set to WGS84.grv, and set the max degree and max order to 70 and 50, respectively:
HPOP */Satellite/Satellite2 Force Gravity "C:\STKInstall\STKData\CentralBodies\Earth\WGS84.grv" 70 50
To set Solid tides to consider the full solid tide model, and to include time dependent solid tides, with a minimum amplitude of 0.02 meters:
HPOP */Satellite/Satellite1 Force SolidTides Full IncTimeDep On MinAmplitude 0.02
To turn on use of Ocean tides, with maximum degree set to 12 and minimum amplitude set to 0.02 meters:
HPOP */Satellite/Satellite1 Force OceanTides On MaxDegree 12 MinAmplitude 0.02
To turn on use of Albedo for radiation pressure model, with coefficient set to 56:
HPOP */Satellite/Satellite1 Force RadiationPressure Albedo On Coefficient 56
To turn on use of the Thermal radiation pressure model, with AreaMassRatio set to 4 m^2/kg:
HPOP */Satellite/Satellite1 Force RadiationPressure Thermal On AreaMassRatio 4
To add Mars and Jupiter to the eclipsing bodies list, and remove Moon from the list:
HPOP */Satellite/Satellite1 Force EclipsingBodies Add Mars Add Jupiter Remove Moon
To set ShadowModel, Model and BoundaryMitigation SRP values for HPOPSat:
HPOP */Satellite/HPOPSat Force SRP On ShadowModel None Model GPS_BlkIIR_AeroT30 1.234 5.678 BoundaryMitigation On
This command belongs to the following group(s):
10
STK Programming Interface 11.0.1