Reporting Atmospheric Drag Values

To create a report or graph of the atmospheric drag values from STK, you need to use the High Precision Orbit Propagator (HPOP) and the Analysis Workbench (AWB).

High Precision Orbit Propagator (HPOP)

HPOP accounts for perturbations caused by atmospheric drag, solar radiation pressure, detailed gravitational models of Earth, third-body effects, ocean tides, and Earth albedo effects. If there is another perturbation particular to a single satellite that you have a model for, you can add this to the force model of the HPOP satellite using a plugin.

Create a satellite object in your STK scenario and configure the HPOP propagator for it. HPOP is easy to use; click here for the STK help topic that introduces the propagator and directs you to documentation for all of its settings.
 
Analysis Workbench (AWB)

To familiarize yourself with the AWB, please click here for an  AWB tutorial.
 
Creating the drag vector

Once you have created the HPOP satellite and completed the AWB lessons noted above, you will need to use AWB to create a drag vector.

1. In your STK scenario, open the AWB dialog box by selecting Analysis Workbench from the Analysis menu.
2. On the left side of the AWB dialog box, select the HPOP satellite that you created.
3. Click the Create New Vector button located between the object and component lists in the Vector Geometry tab of the AWB window. Create a vector with the following properties:

Creating the report

Once you have created a drag vector, open the Report and Graph Manager from the Analysis menu.

1. Select your satellite in the object list.
2. Click the "Create a new report style" button.
3. Name the report "Drag" and then press Enter to open the Report Style window. 
4. In the Data Providers list, scroll down and expand the "Vector Choose Axes" folder; the vector that you created is inside this folder.
5. Within the vector's folder, you can see the Magnitude, Direction, and Derivatives of that newly created vector. Move the Data Providers for this vector from the left to the right side of the window by double-clicking them or selecting them and clicking the arrow button between the lists.
6. Click OK to close the window.
7. Double-click the new report style to run this report for the HPOP satellite.

You can repeat the steps above to create a graph style in addition to a report style. The image below is an example report of a highly elliptical satellite with a low-perigee altitude.

Time (UTCG)                             Mag (km/sec^2)        RightAsc (deg)    Dec (deg)
-------------------------------------------------------------------------------------------------------------
15 Nov 2012 00:00:00.000               59.954227                 -92.018               -2.103
15 Nov 2012 00:02:00.000               13.299979                 -93.149               -1.880
15 Nov 2012 00:04:00.000                2.720843                 -94.218               -1.620
15 Nov 2012 00:06:00.000                0.511363                 -95.198               -1.326
15 Nov 2012 00:08:00.000                0.086793                 -96.043               -1.001
15 Nov 2012 00:10:00.000                0.014468                 -96.532               -0.643
15 Nov 2012 00:12:00.000                0.003143                 -96.046               -0.232
15 Nov 2012 00:14:00.000                0.001134                 -94.120                0.254
15 Nov 2012 00:16:00.000                0.000563                 -90.598                0.803
15 Nov 2012 00:18:00.000                0.000313                 -84.015                1.380
15 Nov 2012 00:20:00.000                0.000190                 -73.336                1.828
 
To visualize the direction of this vector in the 3D window, open the properties of the parent satellite. Under 3D Graphics > Vector, add the drag vector.