General Information | What's New? | Transition Issues | Online Help Resources

ODTK 6.1 Release Notes

Including Changes through ODTK 6.1.1, ODTK 6.1.2, and ODTK 6.1.3

These release notes contain information on system and disk space requirements for installing and running ODTK; information on new capabilities and features introduced in the current version of ODTK, including issues resolved from the prior version; transition information -- cautions, workarounds and operational tips -- to help maximize your successful use of the product; and a brief introduction to online help resources.

Unless otherwise indicated, the information presented below reflects the state of ODTK as of version 6.1.0.

General information

This section includes system requirements and background information on ODTK 6.1.0.

System and disk space requirements

The following table sets out minimum and recommended system requirements for ODTK 6.1.0:

ODTK 6.1.0 System Requirements
Memory Disk Space Processor Operating System Browser
Minimum 256 MB 1 GB 800 MHz XP/XP Professional X64,
Windows Vista, Windows 7,
Windows Server 2003 and 2008		 Internet Explorer 5.5
Recommended 512 MB 4 GB 2.0 GHz XP/XP Professional X64,
Windows Vista, Windows 7,
Windows Server 2003 and 2008		 Internet Explorer 6.0

An ODTK 6.1.0 installation requires 200-300 MB of disk space. Running a typical scenario, such as the Sapphire demo scenario that accompanies ODTK 6.1.0 (3 satellites, 5 trackers x 3 days), takes about 600MB disk space for simulator, filter and smother runs. During such a run the memory footprint of ODTK 6.1.0 is slightly over 110Mb.

Windows Server 2008 installations must have the Desktop Experience option turned on before running the ODTK install. This option is available from the Windows Control Panel.

Background

ODTK 6.1.0 is built upon the same verified astrodynamics functions and coordinate conversions as STK and its modules. ODTK 6.1.0 is a matched set of modules, designed to provide orbit determination and analysis support for the entire life-cycle of satellite tracking systems. All phases of systems design can be supported with simulated tracking data, Monte Carlo analyses, and covariance analyses. ODTK 6.1.0 can produce results for satellite orbit parameters by processing one satellite at a time or multiple satellites simultaneously. ODTK is a stand-alone product, not an add-on module to STK.

The main products in this suite are a tracking data simulator, a state-of-the-art optimal sequential filter and a matched optimal sequential smoother. The sequential filter is designed to provide capabilities in support of routine satellite operations, including orbit determination, ephemeris prediction, and bias and maneuver/thruster calibration. The sequential filter produces a realistic covariance for system performance analyses, tasking optimization, and calculation of the probability of collision (in conjunction with STK/CAT). The optimal smoother provides high accuracy post-fit ephemerides in support of mission data products.

Particular care has been taken to ensure that regression tests to ODTK 5 are satisfied, that ODTK 5 scenarios will load and run in ODTK 6.1.0, and that ODTK 5 restart files will initialize in ODTK 6.1.0.

What's New in ODTK 6.1.0?

ODTK 6.1.0 introduces some significant improvements in a number of areas:

Measurement model updates

  • A new measurement model for phased array radars has been added. It supports measurements in range, U, and V coordinates relative to the array face.
  • Two new measurement models (SB TDOA SBE, SB FDOA SBE) have been added to model TDOA/FDOA measurements of a space-based emitter taken by two space-based receivers. The orbits of all three satellites are estimated.

Filter, Smoother, and VLS updates

  • The filter now has the option to apply second order corrections when doing measurement updates. This can be helpful in preventing degradation of filter results in cases where the linearity assumptions of the filter are violated. For example, processing highly accurate measurements after a long gap between measurement passes.
  • Ephemeris generation and predicts can now be output on exactly even time steps as measured from the start of the prediction interval. This is a convenience capability for using ODTK produced ephemeris in other astrodynamics tools.
  • The filter and smoother can now append to an existing .filrun or .smtrun file rather than overwriting it. This can be useful when you want to restart the filter while preserving the existing information for data product generation.
  • The variable lag smoother (VLS) now supports a variable state space so that states can be added or dropped at the filter restart times. This makes the VLS more suitable in actual operations when satellites, trackers, and finite maneuvers may be coming into and out of the state space.
  • ODTK now has the ability to estimate a single time tag bias for all measurements from a single tracker via clock attributes on the tracker (satellite or facility). This is useful when you believe the clock used by a specific tracker is offset from the clocks used by the other trackers.
  • The filter can now change the central body for a satellite at a restart record. This allows a smooth transition from one central body to another without having to start up a second filter.

Least Squares and IOD updates

  • The Least Squares object can be configured to converge on Absolute RMS in addition to the existing Relative RMS. Occasionally the relative RMS will not converge despite the existence of a useful solution as evidenced by an acceptable Absolute RMS.
  • The Least Squares object can now estimate corrections to the user defined parameters in the plugin solar radiation pressure and drag models.
  • A new method for performing IOD for geostationary orbits has been added. To use this method, you must create a Least Squares object and then use the GEO_IOD/LS HTML utility. You can also call the Least Squares method IODLS directly within your scripts. See the functional attribute documentation for more information.
  • The IOD objects now produce an .iodrun file that can be differenced with other run files; the results of which can be reported or graphed.

Graphing and Reporting improvements

  • The Measurement Times graphs have been significantly improved to make them more understandable. They now display tracker names and measurement types rather than tracker IDs.
  • Improvements have been made to declutter the static product builder style list. The styles can now be grouped by user defined tabs to facilitate style selection.
  • The static product builder now allows you to export a report to CSV format.
  • The graphs have been improved to always use anti-aliased mode and a new zoom window is available. When zoomed in, the zoom window will display where you are relative to the overall graph.
  • Querying for the data to support graphs, reports, and export products is now significantly faster.
  • Graph styles now have the options to display grid lines, display a zero line, and to disable the legend. By default the grid lines are off, the zero line is on, and the legend is on.
  • The satellite summary data provider and report now include the current satellite mass.

TDRS-specific enhancements

  • The UTDF tracking data reader now has an option to generate path specific relay transponder IDs when processing TDRS 4L Range or BRTS Range measurements. This is now on by default. To disable it, you must go to the Edit | Preferences | Plugins menu and select the UTDF tracking data provider. Then press the Config field on the far right and set the TDRSPathTransponders flag to false. This must be done for each user.
  • The TDRS 3L Doppler measurement model has been refactored to incorporate a user satellite frequency clock bias as well as a facility measurement bias. This is controlled by the new clock attributes available on the user satellites.

Satellite enhancements

  • The capability to have a plug in drag model, similar to the existing plug in solar radiation pressure model, has been added. The plug in drag model supports user defined parameters that can be estimated.
  • A Runge-Kutta-Verner 8/9 integrator has been added.

General enhancements

  • Multiple ID names and numbers can now be used to identify satellites and trackers. This is useful when processing measurements from different tracking networks that do not use the same identifiers. See the Help for "Tracking ID Aliases"
  • New stochastic sequence models have been added for estimating tracking biases and force model parameters.
    • Random walk
    • Vasicek
    We have found the Vasicek model to be useful for estimating the force model parameters because it solves for a long-term correction in addition to a short term correction. The existing Gauss-Markov model only solved for a short-term correction. The long-term correction allows for more accurate predicted ephemeris to be generated for the case when the filter or smoother has found a significant correction to the parameter being estimated.
  • The IRI2001 ionosphere model has been replaced with the IRI2007 ionosphere model.
  • Preview Tracking Data information is now available via the scripting interface. This makes it useful to programmatically query the tracking data to determine which satellites and trackers are available.
  • The MeasTypes attribute previously contained all measurement types by default; in 6.1, the MeasTypes list is empty by default, and now an empty MeasTypes list is equivalent to having all measurement types defined. This reduces the size of scenario files and removes the burden of adding new measurement types for new releases to older scenarios. It is also consistent with the behavior of other lists in ODTK (e.g. empty means all possible choices). To recover the previous behavior of having an empty MeasTypes list, set to false the new EnableMeasTypes attribute for either the Satellite or GPSSatellite object.

Version Changes in Tracking Data Interface

The following table shows changes in the tracking data interface between ODTK 5 and the current version:

ODTK 5  ODTK 6 
ODTK.Application ODTK.Application
ODTK5.Application ODTK6.Application
   
AgAttrAutomation5.AgAttrBuilder AgAttrAutomation6.AgAttrBuilder
   
AgMach10_5.AgODObsSet AgMach10_6.AgODObsSet
AgMach10_5.AgODObsSetCollection AgMach10_6.AgODObsSetCollection
AgMach10_5.AgODTrackingIDList AgMach10_6.AgODTrackingIDList
AgMach10_5.AgODRealList AgMach10_6.AgODRealList
AgMach10_5.OLEDBDataSource AgMach10_6.OLEDBDataSource
   
AgOdtkPlugin5.AgOdtkPluginSite AgOdtkPlugin6.AgOdtkPluginSite
   
IAgODProvideTrackingData5.AgODGenericObs IAgODProvideTrackingData6.AgODGenericObs
IAgODProvideTrackingData5.AgODProvideB3TrackingData IAgODProvideTrackingData6.AgODProvideB3TrackingData
IAgODProvideTrackingData5.AgODProvideCobTrackingData IAgODProvideTrackingData6.AgODProvideCobTrackingData
  IAgODProvideTrackingData6.AgODProvideDSNTrackingData
  IAgODProvideTrackingData6.AgODProvideEphemerisTrackingData
IAgODProvideTrackingData5.AgODProvideGenericTrackingData IAgODProvideTrackingData6.AgODProvideGenericTrackingData
IAgODProvideTrackingData5.AgODProvideGeoLocTrackingData IAgODProvideTrackingData6.AgODProvideGeoLocTrackingData
IAgODProvideTrackingData5.AgODProvideGeoscTrackingData IAgODProvideTrackingData6.AgODProvideGeoscTrackingData
IAgODProvideTrackingData5.AgODProvideGPSNavTrackingData IAgODProvideTrackingData6.AgODProvideGPSNavTrackingData
IAgODProvideTrackingData5.AgODProvideILRSTrackingData IAgODProvideTrackingData6.AgODProvideILRSTrackingData
IAgODProvideTrackingData5.AgODProvideLanceTrackingData IAgODProvideTrackingData6.AgODProvideLanceTrackingData
  IAgODProvideTrackingData6.AgODProvideMDPTrackingData
  IAgODProvideTrackingData6.AgODProvideOASYSTrackingData
IAgODProvideTrackingData5.AgODProvideRAWPRTrackingData IAgODProvideTrackingData6.AgODProvideRAWPRTrackingData
IAgODProvideTrackingData5.AgODProvideRINEXTrackingData IAgODProvideTrackingData6.AgODProvideRINEXTrackingData
IAgODProvideTrackingData5.AgODProvideUTDFTrackingData IAgODProvideTrackingData6.AgODProvideUTDFTrackingData
   
AgHtmlServer.AgHtmlServerInitOD50 AgHTMLServerODTK6.HTMLServer
   
HTML Utilities that are run inside ODTK and use HTML Server should instantiate it with:
   window.external.CreateObject("AGI HTML Server")

Capabilities Added and Issues Resolved From the Prior Release

The following table identifies limitations and issues that have been resolved in the current release, as well as new capabilities and improvements that have been added:

For convenience, this table includes all enhancements and resolved issues believed to be significant, including some that are discussed in more detail above.

New Capabilities and Resolved Issues
Tracking No. Description
03866

An optional timing bias has been added to the measurement models. The implementation allows for a single timing bias that applies to all measurements from a single tracker. The user may apply an apriori bias and/or simulate/estimate the bias. Estimation of the timing bias is enabled only through the filter/smoother and VLS; it is currently not an option for Least Squares.
05909

Several methods for addressing higher order effects which may degrade filter performance have been added: the second order Gaussian filter and two underweighting schemes.
07290

Three new graph styles have been added to allow users to visualize what measurements are available in the tracking data files loaded into the scenario.

  • Measurement Times By Sat - graphs the times measurements were available and sorted by satellite.
  • Measurement Times By Tracker - graphs the times measurements were available and sorted by tracker.
  • Measurement Times by Type - graphs the times measurements were available and sorted by measurement type.

These new graph styles replace the existing graph styles Measurement File Preview, Measurement File Preview GPS, and Measurement Times.
07630 A graph no longer displays when the 'export only' option is selected.
23344 Tracking IDs may now have aliases which allows for satellite, facility, GPS satellite and GPS receiver objects to use multiple IDs. IDs may be numeric or alphanumeric.
38926 Processing of Phased Array Face Angle measurements has been added.
39037 A Random Walk stochastic sequence has been added as an option to model measurement biases, transponder biases, and retro delay states.
49198 A Vasicek stochastic modeling option has been added for the estimation of measurement bias, transponder bias and retro delay states. The Vasicek stochastic sequence capability enables the estimation of two observable time-varying scalar biases, with two exponential half-lives, for each scalar sequence. One of the two exponential half-lives is specified by user input, and may be called a short half-life. The second half-life has an infinite time horizon.
49262 An new algorithm for GEO initial orbit determination (IOD) method using LS has been implemented. The LS algorithm executes a one-dimensional search in mean argument of orbital longitude until LS convergence is obtained with an orbit estimate in the GEO class. This algorithm is not limited to any specific observation type.
49917 A drag plugin capability has been added which mirrors the SRP model's Light Reflection plugin. Reports and graphs have been added to show values estimated by the plugin.
50220 A true/false option has been added to use more up-to-date Ap data from SpaceWeather-All-v1.2.txt instead of the original Ap data from IRI2001.
50456 Dynamic graphs now display multiple trackers.
51137 There is a new dynamic report named Instant Maneuver Estimate Update which reports filtered instant maneuver estimation data. The data is displayed during a filter run when the filter is configured to estimate instant maneuvers, and the data is updated during maneuver estimation and until the estimate converges. If there are more than two maneuvers being estimated in a filter run, by default the report will show data for the two latest maneuvers.
51341 The ability to add custom tabs to the Static Product Builder and to populate them using the drag and drop method has been added.
51540 The capability to perform ephemeris prediction on purely even time steps has been added. In prior versions of ODTK the output nodes for ephemeris prediction were aligned to a preferred evenly spaced grid which was determined based on the requested time step. The nodes on the preferred evenly spaced grid have the property that represent an integer number of time steps from 00:00Z. The new option allows ephemeris to be predicted from the satellite, filter or smoother objects on purely even time steps from the start of the prediction interval meaning that alignment to the preferred grid is not enforced.
51903 There is a new dynamic report named Instant Maneuver Estimate Update which reports filtered instant maneuver estimation data. The data is displayed during a filter run when the filter is configured to estimate instant maneuvers, and the data is updated during maneuver estimation and until the estimate converges. The scroll bar can be used to see data for any maneuvers that were displayed prior to the two latest maneuvers.
52025 An error which resulted in ODTK crashing during a filter run when two instant maneuvers with the same name were present on the same satellite and when the filter was confiured to estimate corrections to the instant maneuvers has been corrected.
52219 It is now possible to append to filter and simulator data archive run files when running in Restart or Autorestart mode.
52408 To generate histograms during a filter or simulator run, the OutputMeasHistory setting must also be true.
52543 New optional convergence tests based on the absolute weighted RMS have been added to Least Squares.
52846 Reports can now be exported in CSV format.
52856 Residual graphs now display faster than in previous versions of ODTK.
53103 When starting ODTK via COM, the popup dialog that appears when there is a problem with a license is no longer displayed and the application gracefully fails without waiting for input from the user. The exact error can be retrieved by running a debugging monitor before starting the application.
53342 If the ODTK application is started via CreateObject, it will not attach itself to a pre-existing copy of ODTK that was started manually by the user.
53389 The user can now change the size of the points shown on graphs.
53500 The option to specify zero lines on graphs has been added.
54187 The Ionosphere Model has been updated to IRI2007.
54316 A measurement selection issue was fixed with scenarios containing a (Target) Satellite using the IOD Gooding method, and an SB Tracker satellite. Measurement files including ground angle measurements to the the SB Tracker were incorrectly included as measurement choices for the Target satellite IOD. This has been fixed.
54328 An option has been added to the UTDF tracking data reader to model TDRS path specific relay transponders when using 4L Range and BRTS Range measurements. When the TDRSPathTransponders flag is true, a unique relay transponder ID will be created and passed into the measurement model. The new transponder IDs are:
  • SA1 - SA1 = 11
  • SA2 - SA2 = 22
  • MA - MA - 1 = 331
  • MA - MA - 2 = 332
  • MA - MA - 3 = 333
  • MA - MA - 4 = 334
  • MA - MA - 5 = 335
  • MA - MA - 6 = 336
54343 Default scenario times have been moved to 1 Jul 2011 - 2 Jul 2011
54366 Drag has been added to the list of accelerations which can be included in the list of variational equations used in the computation of the state error transition function.
54609 Vasicek and Random Walk Stochastic Sequences were added as options for estimatiing the ballistic coefficient associated with the Drag Spherical Model. Note that this option is only available when using the White Panel Spherical model; i.e they are not available for estimating parameters input via Drag Plugins. This option resulted in a new attribute layout for the satellite Drag scope. Please refer to Help for details.
54611 Vasicek and Random Walk Stochastic Sequences were added as options for estimatiing parameters associated with Solar Pressure Modeling. Currently these options are only available when using the White Panel Spherical and GPS SRP models; i.e they are not available for estimating parameters input via SRP Plugins. This option resulted in a new attribute layout for the satellite SolarPressure scope. Please refer to Help for details.
54946 LS now estimates corrections to plugin drag and SRP models, includes estimates to 2-parameter models in the summary report, and sets initial force model estimates to zero during the state transfer function.
54947 During a filter restart run, it is now possible to update parameters associated with drag and solar pressure force model plugins.
55414 An issue where the ODTK Simulation would ignore the Satellite solar pressure initial state error estimate setting was fixed.
55653 A rotational-based method is now used to determine attitude partials for incidence partials in a body frame.
55670 The option to steer (or not steer) the simulated stochastic sequences for some state parameters so as to keep the �total estimate� for that parameter positive has been added. This includes the satellite density, the satellite ballistic coefficient, the satellite solar pressure (Cp and K1), the transponder bias, and laser retroreflector delay parameters. The "total estimate" means the addition of the "constant" value with the current error estimate. Steering the sequence to be positive makes sense physically, but steering also results in a sequence that may be non-random and possibly violates the statistical specifications of the sequence itself, complicating one's ability to interpret the results based on the simulation. Prior to this option being added to ODTK, these parameters were always steered to be positive. With the addition of this option the default for new scenarios is to not steer these parameters. Scenarios built prior to this option will still default to enable the bounds checking and should produce the same results as before.
56291 The TDRS 3L Doppler measurement has been rehosted to model a user satellite frequency clock bias rather than a facility measurement bias.
56622 PreviewTrackingData() information can now be viewed using the Scripting Tool.
56838 Graphing speed has been improved.
56839 Multiple improvements were made to the graphing capabilities of ODTK, including alpha shading, anti-aliasing, and adding a zoom window.
56898 Graph tool tips no longer flicker when running under Windows 7.
56999 The capability of the VLS has been extended to handle filter state space changes (add, delete, replace) made at a filter restart time.
57011 The sample tracking data reader plugin TrkData.TB3.VBScript.wsc now correctly reads Type 8 observations in the Transmit B3 format. Previously the range, E, F, and G positions were off by one column.
57023 An issue in which the units conversion for velocity were not working correctly in the user interface has been fixed.
57099 Two new measurement models (SB TDOA SBE, SB FDOA SBE) have been added to model TDOA/FDOA measurements of a space based emitter taken by two space based receivers. The orbits of all three satellites are estimated.
57142 A correction was made in computing the X, Y, Z error sigmas in the Facility Location Estimates report.
57180 The GoodingIOD method has been modified to accept (phased array) face horizontal / face vertical, and DirCos East / DirCos North measurement pairs in addition to az/el, ra/dec, and X/Y pairs.
57294 When processing measurements in the B3 observation format, the ability to transform an azimuth/elevation angle pair to the equivalent direction cosine measurements was broken. This problem was unique to the B3 measurement format and has been corrected.
57312 ODTK will no longer crash if you try to graph too many points. It will simply fail gracefully and provide error messages in the Message Viewer.
57318 Custom data editing and residual editing did not work with B3 Obs files. This has been corrected.
57357 User can now add mulitple custom interval files in one step.
57395 The residual editing schedule was not respecting measurement types when entered manually; when using the graphical residual editing capability, it was. Now newly created residual editing lists will work as intended.
57397 A problem has been fixed where .difrun files produced directly from the smoother did not mark the maneuver events correctly. All maneuvers would show up on graphs even if they were not for the selected satellite based on the data limiting in the static product builder inputs.
57400 The Differenced SRP States graph style has been updated such that each SRP parameter is displayed distinctly.
57402 The Tracker Measurement Bias graph style has been updated to ignore data corresponding to an invalid tracker.
57568 The MeasTypes attribute previously contained all measurement types by default; in 6.1.0, the MeasTypes list is empty by default, and now an empty MeasTypes list is equivalent to having all measurement types defined. This reduces the size of scenario files and removes the burden of adding new measurement types for new releases to older scenarios. To recover previous behavior of having an empty MeasTypes list, set the new EnableMeasTypes attribute for either the Satellite or GPSSatellite object to false.
57662 An error in the generation of filter and smoother ephemeris output on a uniform time grid has been corrected. The prior error could, under certain conditions, result in ephemeris points being improperly excluded from the output ephemeris files. This error was restricted to ephemeris output on a uniform time grid.
57803 The help for the Ui Application and Ui Core object model interfaces are now documented in the help.
57838 The GPScatalog.txt file has been updated with the SVN 62 satellite information. The launch date field has been renamed the clock availability field and the dates updated to reflect when the clock was declared operational. SVN 49 / PRN 01 has not been declared operational yet due to problems identified during the testing so its clock availability date and decommission date are both set equal to the launch date.
57846 The EGM96 and EGM2008 gravity model processing have been updated to include the secular variations in the C20, C21, and S21 gravitational coefficients.
57857 An issue that would have made it possible for the overridden times of a GPS source file to carry over between scenarios that used the same source file has been corrected.
57883 An error message will now display when attempting to open a scenario via script while another scenario is open.
57884 A fix was made to prevent an abort when cutting and pasting a GPS constellation object from/to the scenario.
57929 An error in the CCSDS Tracking Data Message reader resulted in ODTK hanging when a TDM formatted tracking data file contained only measurement types not supported by ODTK. This has been corrected and the reader will now simply return no data under this circumstance. Additionally, 1 way bistatic range and instantaneous doppler have been added to the list of measurement types supported by the TDM reader.
57975 The Runga-Kutta-Verner 8(9) integrator has been added to the list of supported integrators.
58019 The graph styles have been scrubbed to ensure that consistent terminology and look and feel are used. Many of the graphs have been updated to use the term "Correction" in place of "Estimate" to make it clear to the users that what is being displayed is a correction to an existing value and not the total value of the parameter.
58076 The Change Central Body Tool has been modified to add the capability to transition between CBs within a filter run.
58106 The various consistency tests graph styles have been updated to be easier to read and use consistent terminology.
58186 The current satellite mass has been added to the "LastSatelliteState" table and to the filter "Satellite Summary" report.
58222 The ResidualsVsReference utility now allows you to make a run while the filter is in Restart mode.
58229 In the white panel, when viewing a list which is empty, a description of the effect of the empty list is now displayed. For example, when viewing a satellite list which is empty, the message "An empty list allows all satellites to be used" will be shown.
58253 The Residuals Vs. Reference html utility has been updated to allow specifying the use of embedded ephemeris. You can now run the filter in ModelMeasOnly mode and have a SB Tracker use an embedded trajectory.
58317 The SRP.LightReflection plugin code has been moved up one directory level in the install, to <Install Dir>\CodeSamples\Extend.
58334 Ionosphere model data is now properly available for download.
58381 In version 6.1.0, the StateName for the spherical SRP model changed from "Scale" to "Cp". Data files created prior to version 6.1.0 will have the state name updated automatically when read into ODTK v6.1.0. Any scripts that modify the restart record's stochastic parameters will need to be updated.
58625 The units of the GFDOADot WhiteNoiseSigma attribute was changed from "Hz" to Hz/sec". This attribute is included in the Facility MeasuremenStatistics. Previous scenarios containing this attribute will be converted upon loading the scenario. However any user scripts which set the units of this parameter must be converted manually to use "Hz/sec".
58678 The 'Tropo Model' field in the MeasurementHistory data provider was fixed to display the correct model identifier.
58815 The DragModels plugin code has been moved up one directory level in the install, to <Install Dir>\CodeSamples\Extend.
58822 Filter will now run to the stop time when there are no observations and the StopMode = TimeSpan or StopTime. A warning message will be displayed in the message viewer.
58865 The capability has been added to IOD to optionally output an .iodrun state history file containing the output IOD orbit state and epoch.
58877 The option to use measurement file embedded trajectory will now succeed when modeling SBRange measurements.
58918 The option to specify grid lines in graph styles has been added.
58900 In Least Squares, transformation of input (azimuth, elevation) observations to direction cosine measurements has been corrected to be tracker dependent. Transformation occurs when the tracker Measurement Statistics includes {DirCos East, DirCos North} and the LS measurement types includes {DirCos East, DirCos North}.
59045 The UTDF tracking data reader has been updated to include support for the tracking IDs used for TDRS 11-14.
59235 Histogram graphs will now display ALL the available histograms and will not automatically zoom in to display the first 4. This may result in a lot of histograms being displayed on a single graph, in which case the user should use the data limiting capabilities of the static product builder to reduce the number of histograms.
59280 The user can now specify the legend location on graphs in the style file as well as hide the legend from view.
59361 A problem was fixed with the Least Squares object causing a crash when trying to run using a facility with an az-el mask.

Transition issues

This section presents transition issues of importance to the user, including operational tips and caveats to help smooth the path to successful use of ODTK, as well as a list of limitations and unresolved issues of which the user should be made aware.

Transition matters

It is suggested that you review the following list of cautions, workarounds and operational tips before using the current version of ODTK:

Updating custom Report and Graph styles for ODTK 6

Users that have created their own custom report and graph styles in ODTK 5 will need to update them to work with ODTK 6. Since ODTK 5 report and graph styles are not compatible with ODTK 6, a tool has been provided to convert your ODTK 5 custom styles to ODTK 6 styles. The tool is called ODTK_Style_Update50To60.pl, and is found in your install area under AppData\Scripts. This tool will convert all report and graph styles in the designated directory and store them to a new directory. It is recommended that you use a different folder for output, so that your ODTK 5 styles are not overwritten. After converting the report styles, we recommend that you verify them using the procedure below.

Changes in Database Table Contents

From release to release, the contents of database tables used in the definition of report and graph styles may change, usually through the addition of new elements to the record definitions. These changes can impact the content of custom report styles created by the user. Before attempting to use a report style generated with ODTK 5 (or a prior version) with ODTK 6, a Verify Database operation should be performed and a new copy of the report style should be saved to a new directory. Overwriting the old style will cause that style to work incorrectly with the prior version of ODTK. The Verify Database operation is performed by highlighting the report style in the Static Product Builder, clicking on the Edit button then right clicking on the Database Fields and selecting Verify Database. After the verification completes, save the style.

Scripting Guide Updates

Please see the ODTK Scripting Guide for changes to scripting interfaces and additional scripting examples.

Functional Attribute Changes

The functional attribute CreateDifference() now takes an additional parameter. See the description for Item 46466 above.

Obsolete Scenario Attributes

As a result of updating our data thinning and data editing capabilities (items 32929 & 45188), the following scenario attributes are now obsolete in ODTK 6.0:

     - Measurements.EditingMethods.ThinningTime
     - Measurements.EditingMethods.GrossRawData
     - Measurements.EditingMethods.InclusionTimes
     - Measurements.EditingMethods.ExclusionTimes

If you load a scenario file with these attributes set, we will attempt to convert them (except GrossRawData) and populate these new scenario attributes:

     - Measurements.ViewAndSave.CustomDataEditing.Enabled
     - Measurements.ViewAndSave.CustomDataEditing.Schedule

Note that this will only have the effect of applying the editing methods to the viewing of measurements using the reporting tool, or to the saving of measurements to a file. It will not affect the measurements processed by the filter or during a least squares run; to do so, you will need to duplicate this table for the filter or least squares object.

Scripting support for these attributes no longer exists.

Obsolete Satellite and Facility Attributes

As a result of updating our data thinning and sigma editing capabilities (REQ 32929), the following satellite and facility attributes are now obsolete in ODTK 6.0:

	- MeasurementProcessing.ThinningTime
	- MeasurementProcessing.ResidualEditing.NominalSigma
	- MeasurementProcessing.ResidualEditing.Dynamic.Enabled
	- MeasurementProcessing.ResidualEditing.Dynamic.HighSigma
	- MeasurementProcessing.ResidualEditing.Dynamic.NumRejectToStart
	- MeasurementProcessing.ResidualEditing.Dynamic.NumAcceptToStop
	- MeasurementProcessing.ResidualEditing.Dynamic.InitialHighSigmaDuration

These attributes are ignored when loaded from files from a previous version, and scripting support for these attributes no longer exists.

The thinning time is now defined for processing measurements in the filter or least squares objects under the new attributes:

	- CustomDataEditing.Enabled
	- CustomDataEditing.Schedule

The residual editing sigma and dynamic residual editing parameters have been moved to the filter object under the new attributes:

	- SigmaEditing.Defaults.NominalSigma
	- SigmaEditing.Defaults.Dynamic.Enabled
	- SigmaEditing.Defaults.Dynamic.HighSigma
	- SigmaEditing.Defaults.Dynamic.NumRejectToStart
	- SigmaEditing.Defaults.Dynamic.NumAcceptToStop
	- SigmaEditing.Defaults.Dynamic.InitialHighSigmaDuration
	- SigmaEditing.CustomSigmas.Enabled
	- SigmaEditing.CustomSigmas.Schedule

Since the nominal sigma attribute has been removed from the satellite object and was needed for Least Squares runs, the attribute is duplicated in the Least Square Stages List and will default to a value of 3:

	- Sigma

Obsolete Product Builder Attributes

As a result of updating our graphing capabilities the following Product Builder attributes have changed in ODTK 6.0. For every data product there was an Outputs.Export attribute that contained Options. The Options attribute has been removed because it was redundant. All the attributes under Options still exist but are now parented directly under Exports. For example, assuming you wanted to change the output file name for a product named "Azimuth Residuals". The resulting attribute path from ODTK 5.1 was 

	ODTK.ProductBuilder.DataProducts.Azimuth Residuals.Outputs.Export.Options.FileName
but in ODTK6 it is now 
	ODTK.ProductBuilder.DataProducts.Azimuth Residuals.Outputs.Export.FileName

Unresolved issues affecting the current release

The user should be aware of the following limitations and unresolved issues affecting ODTK as of the date of this release.

Unresolved Issues
Tracking No.Description
07071Tracker satellites cannot share tracking IDs with GPS constellation PRN numbers. If a scenario contains both an optical tracker satellite and a GPS constellation, and the tracker satellite has a tracking ID between 1-36, the tracking ID will become ambiguous.
10186Users should not name objects using class names like Filter, Smoother, Simulator. Refer to the "VBA to VB.NET Migration" section of the ODTK Help.
23349LaunchPad doesn't format dates in local format, it always uses MM/DD/YYYY even if machine is configured to show dates as DD/MM/YYYY.
26002It is not possible to Export the HTML generated by the ViewScenario.htm utility to Microsoft Excel, even though the option is offered.
29439To avoid abnormal terminations that may occur when FLEXlm code is run with Windows Data Execution Prevention enabled, you need to change the DEP settings: Open the "System Properties", click on the "Advanced" tab and click on "Performance,� Settings�" button. This will bring up a dialog with three tabs. Click on the "DEP" tab and set the option to: "Turn on DEP for essential Windows programs and services only". You may need to restart the computer after that.
30517The Plugins tab does not refresh the SupportsSave column. When you add a new plugin tracking data reader and click Apply, the column labeled SupportsSave is not refreshed. By default the value in this column is false, but after you add a new tracking data reader that supports save, then the value in this column should be true. The user must dismiss the panel and pull it back up to get the correct value.
31034After a long predict, the covariance is quite large. A very large measurement update can drive the filter covariance negative.
31802A GPS constellation object does not populate the PRNList until properties are applied. We suggest that when you first assign a source file to a GPS constellation, you press Apply before double-clicking on the PRNList to view its contents.
32139State File To SP3 utility limits output to GPSSatellites named PRN01, PRN02, etc.
36839If ODTK aborts or runs out of disk space then any active runfile is not saved in a valid state. This issue can not be corrected without a big impact on processing speed (opening and closing the file and opening to append). The user is advised to monitor disk utilization and plan for large runfiles from ODTK to avoid disk space issues.
38689When attempting to integrate an orbit in low altitudes, such as < 90 km, the integrator may perform poorly and hang. This problem may be overcome by changing the integration method or integrator settings.
42045The SB range measurements ignore the optional tracker vector information. If you have a B3 file with type 8 or 9 measurements that are supplying the tracker position then you will get bad answers if you have your tracker satellite set up with its ephemeris source set to " Meas File Embedded Trajectory ".
42672Dynamic Earth Data does not use file find paths. Do not attempt to change the location from the default location.
45226ODTK does not support saving and loading of files that use multi-byte character sets.
47065The legend will not appear for a graph if there are more than 20 sets/lines of data being displayed. This is a limitation in the graphing package, designed to ensure that the graph contents are still visible when many items are being displayed. Users can still determine which line belongs to what data set by hovering their mouse over it and waiting for the Tool Tip to be displayed that shows the identity of the line.
52010Older AMD chips do not support "Streaming SIMD Extensions 2 (SSE2)". SSE2 was first used in ODTK v6.0. The following AMD chips do support SSE2:
  • AMD K8-based CPUs (Athlon 64, Sempron 64, Turion 64, etc)
  • AMD Phenom CPUs
  • and newer

What's New in ODTK 6.1.1

ODTK 6.1.1 is primarily a maintenance release; however there are some new capabilities that users should be aware of:

Tracking data providers

  • The tracking data provider interface IAgODProvideTrackingData has been updated to support a CloseFile method. If you have written custom tracking data plugins that use this interface, we recommend that you update them and implement the new method. ODTK now calls this method to explicitly close tracking data files that were opened when running the filter, least squares, reporting, etc. This allows the user to update these files as necessary when previously they would have been held open until the scenario was closed.

    The CloseFile method is optional for the 6.1.1 release. We recognize that users may not be able to upgrade their plugins and still want to take advantage of the other 6.1.1 improvements. ODTK will query your plugin to see if it has the CloseFile method and call it if available. If not it will simply skip this step and you will have the same behavior as in ODTK 6.1.0.

    We anticipate making the CloseFile method mandatory during our next major ODTK upgrade (ODTK 7.0). We encourage users to begin implementing the CloseFile interface in preparation for that release (at least 6 months from now). Our example code that ships with ODTK has been updated to provide sample implementations. If you have any questions about updating your code, please call AGI tech support and we will help you out.

  • The CCSDS TDM format reader has been updated to support X/Y angles. It can also write out TDM files.

Least Squares updates

  • The user can now select a QR, Singular Value Decomposition, Factorization, or a Divide and Conquer method to solve the least squares equations.


  • There is a new option InitialEdit to allow the LS object to reject outliers on the first iteration based on the RMS of the initial set of residuals.

Measurement model updates

  • A new measurement model for Accelerometer data has been added. Accelerometer measurements are treated as observations to compute corrections to force modeling parameters and accommodate cases where the accelerometer is only enabled at specific times of interest such as during thrusting. Accelerometer objects can now be added to satellites to utilize this data.

Filter, Smoother, and VLS updates

  • The filter now generates data to support a QQ plot with Royston acceptance bounds. The QQ plot is a useful method for analyzing the "white"-ness of the residuals when there aren't very many of them (more so than plotting a histogram). This plot provides another means by which the fundamental assumptions of the sequential estimator can be tested to provide confidence in the resulting state and state error covariance estimates.

Satellite updates

  • The gravity process noise model has an additional parameter MeanMotionUncertaintyScaling to allow a scaling of the gravity process noise contribution to the in-track uncertainty growth. This is typically used only when performing OD around central bodies whose gravity fields have a large amount of uncertainty (i.e. not the Earth). In such cases, gravity errors tend to be favorably aliased into semi-major axis length errors so that the rapid growth of in-track error predicted by propagation of an orbit state in an uncertain gravity field is not observed.

HTML utilities

  • The Ephemeris Extraction tool was updated to allow ephemeris to be output in any reference frame. The underlying attribute function ExtractEphemeris has been updated to support this. If you have code that is calling ExtractEphemeris then we recommend that you review the new calling parameters and update your code as necessary.

Reporting and Graphing

  • Orbit Period and True Anomaly parameters were added to the SatelliteState table and are available for reports to use. A new report style "Satellite Classical Elements Plus" was added that displays these.


  • The RangeModulus is now included in the TrackingData table. When processing DSN TRK 2-34 formatted measurements users can now extract the range modulus values.

Tracking systems

  • The ILRS tracking system files have been updated to reflect the latest coordinates and eccentricities from the SLR community.

Changes introduced in ODTK 6.1.1

The following information applies to ODTK 6.1.1.

Capabilities added and issues resolved in ODTK 6.1.1

The following table identifies limitations and issues that have been resolved in the current release, as well as new capabilities and improvements that have been added:

New Capabilities and Resolved Issues in ODTK 6.1.1
Tracking No.Description
22564A CloseFile method has been added to the IAgODProvideTrackingData interface used by custom tracking data plugins. It allows ODTK to close tracking data files so that they are not held open until the scenario is closed. All users are encouraged to update any custom tracking data plugins to add this new method. For backwards compatibility, ODTK 6.1.1 will still work with your old tracking data plugins even if they do not implement this method. However, we anticipate making this new method mandatory with the next major upgrade of ODTK.
31917Users can now load a different data product from a script and the Static Product Builder will show the change.
44892ODTK had an issue of not reloading the FluxData file if it's content had changed under the same file name. A new function ODTK.Scenario(0).ReloadFlux() has been added that forces clearing of the flux data cache and subsequent reloading of the flux data.
50469Users can now export graphs in EMF format when in zoom mode.
54936The ability to process accelerometer measurements has been added. Measurements are processed based on the specification of accelerometer and accelerometer sensor objects. The implementation allows accelerometer inputs to be used when available without requiring them. Accelerometer measurements are used to provide corrections to non-conservative force models including atmospheric drag, solar radiation pressure and thrusting. Accelerometer scale factors and biases can be solved for as part of the estimation process.
55801The CCSDS Tracking Data Message (TDM) file reader was updated to read XY angle measurements and now allows measurements to be saved in the TDM format. Only the following measurement types are supported: Azimuth, Elevation, Range, Doppler, X angle, Y angle, Right Ascension, Declination.
56842A scenario with a simulator object in it and lots of possible tracking strands (many trackers defined in the scenario) would take a minute or longer to close the scenario or exit ODTK. This problem has now been fixed.
58334Ionosphere model data is now properly available for download.
59363In Least Squares (LS) an option was added to allow LS to reject outliers on the first iteration by making an initial pass through the residuals to compute a RMS but performing no update to the state.
59647The capability to produce a Residual Ratio QQ-Plot with Royston acceptance bounds has been added.
59971IRI2007 code has been modifiy to read unmodified IRI data (ig_rz.dat).
60041The static product builder will respect the file extension set by a script when creating a new data product using a script.
60326Intel MKL libraries were updated to version 10.3.6.233 that includes support for Intel® Xeon® processor 5400 series and Intel® AVX optimizations for large matrix operations.
60401There was an issue in which the Normal Point Range model ignored the Scenario.RoundTripRepresentaion one-way/two-way flag when entering the WhiteNoiseSigma value. The value entered was always being treated as a two-way value. This issue was fixed. This change will only affect runs using new scenarios and new NP WhiteNoiseSigma entries. This change will not affect results running a saved scenario if no changes are made to the NP WhiteNoiseSigma.
60413

If the Intel MKL is available, the LS Solution will now use the MKL LAPACK LLS driver algorithms. A new LS attribute has been added to select the driver to be used: "QR", "Factorization", "Single Value Decomposition", or "Divide And Conquer".


The "Filter" grid LS ephemeris opriton is no longer supported. Output will now be on a uniform grid.

60469The ability to reduce the affect of gravity process noise on the accumulation of in-track uncertainty has been added. This feature is useful in cases where the gravitational field has a large amount of uncertainty (central bodies other than the Earth). In such cases, radial acceleration errors are often aliased into an error in the estimate of semi-major axis length which offsets rapid in-track error growth.
60545An internal error which could cause ODTK to crash when using 2nd-order corrections in the filter has been corrected. This error could be encountered in scenarios using space-based trackers where the tracking satellite is not directly tracked itself.
60662Small pads (one millisecond) have been added around measurement times for measurements graphically selected for residual editing to account for cases where measurement time tags carry more precision than the ODTK GUI. This corrects the residual editing behavior for these cases where the requested residual editing action (Reject or Ignore) was not being honored due to rounding of the time tags in the residual editing list.
60676A reference frame selector was added to the Ephemeris Extraction Tool.
60756The covariance from a reference ephemeris file was not being used when calculating measurement uncertainties. This problem occurred when running the filter in residuals vs. reference ephemeris file mode. This has been corrected.
60819A new report style, Satellite Classical Elements Plus, displays a satellite's true anomaly and orbit period. These values are in the Satellite State data provider and are available for export and graphing.
60905The histogram graphs no longer scale the X axis to display 4 histograms when there are less than 4 to be displayed.
60994If ODTK is started from a script and UserControl=false then ODTK will no longer popup the dialog box confirming to save the modified scenario on close.
61003ODTK 6.x full screen mode has been changed to be consistent with STK.
61053An error in the processing of space-based angular measurements which restricted their proper use to applications where the observing satellite was in orbit about the Earth has been corrected.
61259When the filter was configured in Restart mode the filter stop time was being checked against the start time rather than the restart record time. This resulted in misleading errors indicating the stop time was incorrect. This has been corrected.
61425The FilePath HTML utility was referencing the scenario IRI2001 ionosphere model attributes and was not displaying the rest of the file paths in the scenario. It now correctly uses the IRI2007 ionosphere model attributes.
61430The UTDF tracking data reader was updated to throw out only angle measurements if the autotrack filter was on and the data indicated the antenna was not autotracking. Previously all measurements were being thrown out which could result in the loss of valid usable range and doppler data.
61828Previously if a large number of ODTK instances were run concurrently, each generating output ephemeris at a rapid rate, two instances could end up using the same temporary file for storing temporary ephemeris points, resulting in an incorrect ephemeris file. This has been fixed by including process IDs in the temporary file names.
61830Previously if ODTK was given a corrupted ephemeris file as a reference ephemeris it could crash (for example *.e file containg over 4096 NULL characters) due to buffer overruns. This has been fixed and ODTK should generate an error message instead of crashing.
61882An improvement was made in the light time computation used by the DSN measurement models to allow application of these models to more distant spacecraft. The conversion between Ephemeris Time and Terrestrial Time was not previously precise enough to allow for accurate processing of data in deep space beyond the vicinity of the Earth-Moon system.
61944Average Force Model Bias report now displays Ballistic Coefficient Biases in consistent unit (B = m^2/kg).
61989The gpscatalog.txt file was updated to reflect the recent GPS launch and constellation updates.
62057ODTK no longer crashes when opening a scenario that references a JPL planetary ephemeris file that doesn't exist. ODTK will now display a warning and then default to the DE421 file.
62114The tooltips displayed on graphs when the cursor is hovered over a point now work correctly.
62118An issue in which the Vasicek long term initial error estimate values were not being used by the filter and the value was always set to zero has been corrected.
62121Pressing the enter key with an object selected in the object browser will display the properties page as it had in versions of ODTK prior to 6.1.
62272An error in the scaling of the white noise associated with GPS navigation solution measurements has been corrected. This error affected scenarios where GPS navigation solutions were processed and the white noise scaling option in the GPS receiver measurement statistics was set to scale the user input white noise by either the position dilution of precision (PDOP) or by the component dilution of precision.
62331A fix was made to Least Squares when solving for force model parameters. The fix could result in slightly different solutions than before when solving for force model parameters.
62404Generic obs files now contain more information, specifically: AntennaMountType, ZAngle, AntennaIDs, TransponderIDs, LaserRetroIDs, LinkFreqs, AberrationModel, CartesianComponent, CartesianCoordSys, WNSigma, TrackerVector, RangeModulus and ModelCM.

Version 6.1.1 generic obs files will not be readable by older versions of ODTK.
62453The Edit | Find dialog on the the Object Properties panel was not respecting the Match Case flag. All searches were case insensitive. This has been fixed.
62608The tracking ID set by PODS in an STK facility file is now read and used by ODTK when importing the file into an ODTK tracking system.
62624Graphical residual editing now handles GPS Navsol measurements. Note that residuals are graphed in their X, Y, and Z components, however, all three components are processed--or not--as a group. Selecting any one of the three components will cause all three to be edited.
62628A description of ODTK clock modeling has been added to the math specification.
62782ODTK officially supports Microsoft Windows Server 2003 and Microsoft Windows Server 2008 with this release.
62787An error in the SB Range measurement model has been corrected. The error was caused by a missing update of the position of the tracking satellite during the computation of the second leg of the two-way light time delay. The error introduced in the computation was proportional to the range rate between the satellites multiplied by the one-way light time delay.
62798A change was made to allow LS to estimate ground based GPS receivers' clock parameters.
63015In support of processing the DSN TRK 2-34 sequential ranging data, the observation RangeModulus has been added to the TrackingData table used by reporting and graphing.
63070The Getting Started with Satellite Laser Ranging document was updated to include references to the Consoliated Laser Ranging Data (CRD) format.
63075The International Laser Ranging Service (ILRS) tracking systems have been updated with the latest site positions and offsets.
63337An error in the Finite Maneuver Summary report style has been corrected. The error resulted in simulated perturbation in the radial direction at the start of the maneuver being reported incorrectly. The reported value was, in fact, the simulated perturbation in the intrack direction.
63502An option was added to the built-in B3 data format reader to interpret the position information for space-based trackers to be provided in EFG coordinates.
63530Windows Server 2008 installations must have the Desktop Experience option turned on before running the ODTK install. This option is available from the Windows Control Panel.


Unresolved issues affecting the current release

The user should be aware of the following limitations and unresolved issues affecting ODTK as of the date of this release.

Unresolved Issues in ODTK 6.1.1
Tracking No.Description
60126If you must use Windows Server 2003 then let the ODTK install proceed and fail, then run C:\Program Files\AGI\ODTK 6\bin\AgPluginReg.exe. ODTK will be able to start but some functionality may be broken depending on the lack of Service Pack updates installed on the system.

What's New in ODTK 6.1.2

ODTK 6.1.2 is primarily a maintenance release; however there are some new capabilities that users should be aware of:

Measurement model updates

  • The range measurement model has been updated to allow a transponder ID to be specified with each measurement.
  • New variations of the TDOA/FDOA measurement models have been added where a signal is generated from a ground based emitter, passes through 2 relay satellites and is ultimately received by two distinct ground receivers.
  • The tracker vector for a measurement can now be specified in an EFG pseudo-earth fixed frame (the same as Earth Centered Fixed but pole wander is not accounted for).

Data file updates

  • The leap second data file has been updated to account for the new leap second scheduled for 30 June 2012. This update is also on the AGI FTP site and available via ODTK's Data Update Utility.

Simulator updates

  • The simulator will now respect the facilities minimum elevation angle constraint instead of using a default value of 0 degrees elevation. This allows the simulator to simulate observations at negative elevation angles.
  • The capability has been added to import a simulation schedule directly from the measurement times defined by the scenario measurements files. This option is controlled by the ImportMeasFileSchedule property which has been added to the Simulator.CustomTrackingIntervals definition.
  • An option has been added to control whether to update the scenario measurements file list upon completion of the simulation run. This option is set using the Simulator.Output.Measurements.UpdateScenario property. When set to true (the default), the scenario measurement file list will be updated to include and enable the simulator measurement file(s). When set to false the scenario measurement list will not be updated.

Filter, Smoother, and VLS updates

  • The filter has a new capability to update a tracker bias during a filter restart by taking the estimate out of the bias correction and putting it into the associated constant term without changing (or "re-initializing") the covariance.

Utility scripts

  • A new utility script register_wsc_hkcu.vbs is now included in the install to allow users to register Windows Script Components as a regular user (no administrator rights are required). This makes it easier to write custom tracking data readers or force model plugins.

Changes introduced in ODTK 6.1.2

The following information applies to ODTK 6.1.2.

Capabilities added and issues resolved in ODTK 6.1.2

The following table identifies limitations and issues that have been resolved in the current release, as well as new capabilities and improvements that have been added:

New Capabilities and Resolved Issues in ODTK 6.1.2
Tracking No.Description
58386The capability has been added to allow the two-way range and doppler model to use multiple transponders.
60916A fix was made to prevent Message Viewer column widths from being set to zero.
62628A description of ODTK clock modeling has been added to the math specification.
63828The leapsecond.dat file has been updated to include the leap second on Jun 30, 2012.
63975The Simulator has been changed to use the facility minimum elevation constraint when determining satellite visibility. Previously the simulator used a projection equation equivalent to a zero degree elevation constraint.
63991The capability has been added update to update a sensor bias during a filter restart by taking the estimate out of the bias correction and putting it into the associated constant term without changing (or "re-initializing") the covariance.
64066New variations of TDOA/FDOA measurement models have been added for the case where a signal is generated from a ground based emitter, passes through two relay satellites and is ultimately received by two distinct ground receivers.
64070The HTML utility ScriptingTool was updated to run under Internet Explorer 9.
64091An error in the Least Squares estimation capability that resulted in zero corrections being computed for deep space missions has been corrected. The prior error, introduced in ODTKv6.1.1, was specific to LS processing of objects greater than 10 planetary radii away from their primary central body. Note that the GEO belt is at approximately 6.6 Earth radii, so the vast majority of Earth based missions were not affected by this error.
64092An error in state definition for Least Squares estimation has been corrected. The error resulted in degraded performance of Least Squares estimation when certain object settings identified states for inclusion in filter based estimation which are not currently estimated by Least Squares (facility troposphere zenith delay, facility measurement timing bias, facility location).
64105The Differenced Ballistic Coefficient report style has been updated to correctly report differences in ballistic coefficient estimates. The style had been errantly reporting differenced relative atmospheric density.
64116A fix was made to populate the satellite and tracker name fields when reporting using the TrackingData tables and a tracking data reader that is supplying TrackerNames instead of TrackerIDs.
64141The Astrodynamics Consistency document was updated to address the eclipse shadow mode and solar flux settings.
64146The GPScatalog.txt file has been updated to reflect the latest constellation status.
64204The capability has been added to import a simulation schedule directly from the measurement times defined by the scenario measurements files. This option is controlled by the "ImportMeasFileSchedule" property which has been added to the Simulator.CustomTrackingIntervals definition.
64207The SPICE time.ker file was updated to include the upcoming leap second on Jun 30, 2012.
64353A fix was made to correct a situation where the wrong finite maneuver GM settings were being used on a restart. This situation occured when the user updated the finite maneuver GM white panel settings during a restart. ODTK was incorrectly using the white panel settings instead of the restart values. Note: to update the finite maneuver GM settings during restart one needs to use the filter Restart.StochasticModelUpdates lists.
64526The Appl Prefs file was updated to include Rinex extensions 11o;12o;13o;14o.
64695A Simulator option has been added to control whether to update the scenario measurements file list upon completion of the simulator. This option is set using the Simulator.Output.Measurements.UpdateScenario property. When set to true (the default), the scenario measurement file list will be updated, as has been the case, to include and enable the simulator measurement file(s). When set to false the scenario measurement list will not be updated.
64774Errors in the accounting for estimated finite maneuvers for the purpose of state differencing has been corrected. These issues affected finite maneuver difference reports when a smoother output containing state space changes was used in the state differencing operation. Such cases were possible when maneuver states were added and dropped over multiple filter runs and either the fixed interval smoother was run across multiple rough files or a variable lag smoother was executed in conjunction with the filter. The differencing errors were restricted finite maneuver states.
64818An update has been made to the IAgODGenericObs measurement interface to allow a tracker vector to be specified in an EFG pseudo-earth fixed frame (the same as Earth Centered Fixed but pole wander is not accounted for).
64824A filter-based functional attribute (ViewRestartData) and html utility by the same name have been added to display the state contents of the specified filter restart record.
64873A change was made to the TDOA measurement model to correct the sign error in the accumulation of the tropospheric effect at the receiver. The quantity corrected is only used in measurement deweighting when troposphere corrections at the receiver are not estimated. The correction is expected to be small.
64902A limitation of the simulator which resulted in the inability to generate simulated measurements with time tags whose precision exceeded 0.1 milliseconds has been relaxed to allow the simulation of measurements with time tags to a precision of 1 microsecond.
65025A correction was made to the Propagator Definition files version stamp to allow them to be loaded into STK version 9.2.2.
65283The LS object can now solve for space based (SB) measurement biases.
65286A setting has been added to the process control attributes of filter and simulator objects to provide user control over the maximum number of revolutions that a satellite orbit may be propagated to align the satellite initial state with the start time of the process.
65536A fix was made to allow reading of the "DA" observation type and more than 9 observations per satellite in Rinex 2.20 files.
65626In support of TDRSS, the calculation of translational frequency for MA return Doppler was corrected to support third generation TDRS (TDRS-K, ..). In addition some minor corrections were made to the TDRSS SA services uplink and downlink frequencies which should have very minor effects on ionospheric modeling.
65845
  • An issue with measurement residuals not triggering filter-rejected residual-alert and warning scripts was fixed.
  • Graphical editing of ephemeris measurements was enabled.
65858An error in the generation of maneuver summary information in the Variable Lag Smoother (VLS) has been corrected. The prior error resulted in the reporting of incorrect state corrections in the Finite Maneuver Summary. The error was related to output generation and did not affect the overall estimation solution.
65861An error in the Variable Lag Smoother has been corrected which caused the VLS to produce incorrect maneuver solutions when the filter was run multiple times and the maneuver uncertainties were changed between filter runs.
65865Corrections for troposphere effects have been added to the Herrick-Gibbs IOD algorithm.
65903An error has been corrected in the variable state capability of the Variable Lag Smoother in which erroneous results were generated if the filter was restarted multiple times from the same restart time where a state space change occurred.
65909A new script "register_wsc_hkcu.vbs" is included in the ODTK install under AGI\ODTK 6\CodeSamples\Extend. This script allows users without administrator rights on their PC to register a Windows Script Component under the HKEY_CURRENT_USER area of the registry so that ODTK can find it and use it successfully. This is a common issue with registering custom tracking data readers and custom drag and SRP models.
65952When STK/ODTK are launched via automation and the UserControl property is set to false, user preferences and format preferences will not be saved after the application ends.
66047A problem has been corrected where the maneuver markers displayed on a graph were shown at the wrong times when the graph was being displayed in the GPS time scale.

What's New in ODTK 6.1.3

ODTK 6.1.3 is primarily a maintenance release; however there are some new capabilities that users should be aware of:

Satellite updates

  • The satellite object now exposes the GM “mu” value for the particular gravity model being used by that satellite. This is useful when performing astrodynamics calculations using the satellite’s orbit state.

Measurement model updates

  • ODTK now allows for instantaneous Doppler (i.e. range rate) via the new Doppler Measurement Statistics attribute "InstantaneousModel". Currently this is only supported for Ground based doppler.
  • An integer property, SourceID, has been added to the IAgODGenericObs interface used in conjunction with the IAgODProvideTrackingData interface to provide tracking data observations to ODTK through a plugin interface. These source ids are passed through the estimation process and written to the filter and least squares output files. They are typically used to simplify the identification of residuals as being associated with specific tracking passes, etc.

Least Squares updates

  • Least Squares was modified to allow it to run when the satellite force model parameters are configured to use a Vasicek stochastic sequence.
  • You now have the option to transfer a scaled position and velocity covariance to the satellite.

Filter, Smoother, and VLS updates

  • The filter restart record file sizes are now smaller (the new size is approximately 2/3 the original size). The filter has backwards compatibility code to read the older format restart records.

HTML utilities

  • The StateContent HTML utility will now display information about the states being estimated by a Least Squares object.
  • The RunSTK and RunSTKX HTML utilities now set the covariance ellipsoid color to the same color as the satellite orbit.
  • The ConcatenateSP3File HTML utility was updated to name the resulting concatenated output SP3 file as *_cat.sp3 rather than *.cat. This makes it easier for users to find the resulting .sp3 file and use it directly.

Capabilities added and issues resolved in ODTK 6.1.3

The following table identifies limitations and issues that have been resolved in the current release, as well as new capabilities and improvements that have been added:

New Capabilities and Resolved Issues in ODTK 6.1.3
Tracking No.Description
56897The State Content tool has been extended to include LS objects.
66328A new read only satellite object attribute "sat.ForceModel.Gravity.GMVal" displaying the Central Body GM value was added. This allows scripting users to obtain "mu" through ODTK for astrodynamics calculations.
66601An integer property, SourceID, has been added to the IAgODGenericObs interface used in conjunction with the IAgODProvideTrackingData interface to provide tracking data observations to ODTK through a plugin interface. These source ids are passed through the estimation process and written to the filter and least squares output files.
66723ODTK now allows for instantaneous doppler (i.e. range rate) via the new Doppler Measurement Statistics attribute "InstantaneousModel". Currently this is only supported for Ground based doppler.
66759The Initial State Tool HTML Utility is always propagating the first TLE for a given SSC, rather than the selected TLE. This is only a problem when you have more than one TLE for the same satellite. This problem has been fixed.
66862ODTK Least Squares has been modified to allow it to run when force model parameters are configured for a Vasicek sequence.
66872An issue was fixed with LS in the estimation of drag, solar pressure, and measurement biases when the LS epoch location was not at the beginning of a stage.
66874The UTDF tracking data reader has been updated to follow the UTDF convention of ignoring leap seconds in the computation of the number of seconds into the year. An environment variable, AGI_DO_NOT_IGNORE_LEAP_SECONDS_IN_UTDF, has been added to restore the prior ODTK behavior of honoring leap seconds in this computation.
67133An error in the DSN 3W Doppler model has been corrected where the proper reference frequency was not being used in cases where the reference frequency was not included in frequency ramp information but was still specified with the observation from the tracking data. This is possible when reading DSN 3W Doppler observations from a CCSDS Tracking Data Message.
67154An issue was corrected where ODTK did not correctly load the IOD GPSNavSolution method SelectedReceiver attribute from a saved scenario.
67350The ViewRestart utility was modified to work correctly with scenarios using GPS time.
67462There was some cleanup of the Restart records to eliminate unused items and save storage space.
67496The residual unit string displayed for TDOA measurement types was changed from "ns" to "nsec". This is consistent with standard AGI/STK/ODTK unit registration and allows this unit string to be used by the scripting "GetIn" and "Set" methods.
67568Help documentation was added to clarify the meaning of GPS Source file "start/stop" times displayed in the GPS Constellation object white panel. The "start/stop" times displayed when using RINEX NAV, YUMA, and SEM almanacs as the GPS source file were corrected to be consistent with this definition.
67691The ODTK SNGL license logic was changed to allow OD of a user satellite using measurements relayed through another satellite (e.g. TDRS) as long as the orbits of the relay satellites are not simultaneously being estimated with the user satellite. Estimation of the relay satellite transponder states is allowed.
67720The new user install now delivers a sample ODTK Style Categories.xml file to define some tabs used to display product styles in the Static Product Builder.
67798The RunSTK and RunSTKX HTML utilities were updated to set the covariance ellipsoid to the same color as the orbit line.
68186The LS object now allows negative values to be input for the ballistic coefficient and solar radiation pressure coefficient.
68330An issue was fixed concerning the Filter incorporating measurements contained within the Filter RejectMeasTypes list.
68465The ConcatenateSP3File HTML utility was updated to name the resulting concatenated output SP3 file as *_cat.sp3 rather than *.cat.
68476Maneuver marks on graphs were sometimes labeled in the wrong order even though the marker was at the correct location. This problem could only occur when displaying results from multiple satellites at once in the same graph. This problem has been fixed.
68967A problem was corrected where the Update Type field in the SatelliteStateDiff table was not being set correctly when turning on state differencing in the smoother.
69132A problem was corrected in which the AGI_ODTK_EXPORT_DPI environment variable to override the graph export dots-per-inch parameter was not being honored by the static product builder export capability.
69520The ability to transfer position/velocity covariance from a least squares solution to the satellite object has been added.

Online Help resources

The current version of ODTK is shipped with the following online help resources:

The ODTK Help system

The ODTK Help system appears in the Microsoft HTML Help Viewer, which uses components of the Microsoft Internet Explorer to display help topics and navigational tools. The latter are accessible from the following tabs:

  • Contents - Click on the book and page icons to find the topic of interest.
  • Index - Scroll down the list or begin typing the name of the index item in the text box. When the item you are seeking appears in the list, double-click it or highlight it and click the Display button. If the item is found on more than one help page, a window listing the applicable pages will display.
  • Search - Type in the word or phrase for which you wish to search. To specify an exact phrase, enclose it in double quotes; otherwise, any page containing all of the words in the phrase (not necessarily contiguous) will be listed. After typing in the search term, either press the Enter key or click the List Topics button.
  • Favorites - This tab lets you bookmark help topics to which you might want to refer to frequently. Clicking the Add button places the name of the currently displayed help topic in the list. To delete a topic from the list, select it and click the Remove button.

Context-sensitive Help

F1 Help for OD Attributes

To display context-sensitive help for a property of an OD object, select it in the Object Properties window for the object and click the F1 key.

Help Buttons for Report and Graph Windows

Help buttons are available for the Static Product Builder, the Dynamic Product Selector, the Graph Designer and the Report Designer. Click these buttons for context sensitive help on the functionality in question.

Printable (PDF) documents

Several printable (PDF) documents accompany this version of ODTK, including a set of tutorials (Getting Started with ODTK), a scripting guide, and documents explaining the mathematical and scientific background of ODTK. To access these documents, go to the manuals page.