System Requirements | What's New? | Transition Issues and Limitations | Online Help Resources
ODTK 3.0 Release Notes
Including Changes through Version 3.0.3
These release notes contain information on system and disk space requirements for installing and running OD Tool Kit; information on new capabilities and features introduced in the current version of OD Tool Kit, 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 OD Tool Kit as of version 3.0. Changes introduced in versions 3.0.2 and 3.0.3 are described in separate sections.
System and Disk Space Requirements
The following table sets out minimum and recommended system requirements for OD Tool Kit 3.0:
| OD Tool Kit 3.0 System Requirements | |||
|---|---|---|---|
| Memory | Disk Space | Processor | |
| Minimum | 256 MB | 1 GB | 800 MHz |
| Recommended | 512 MB | 4 GB | 2.0 GHz |
An OD Tool Kit 3.0 installation requires 200-300 MB of disk space. Running a typical scenario, such as the Sapphire demo scenario that accompanies OD Tool Kit 3.0 (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 OD Tool Kit 3.0 is slightly over 110Mb.
What's New in OD Tool Kit 3.0?
Orbit Determination Tool Kit (OD Tool Kit) version 3.0 is built upon the same verified astrodynamics functions and coordinate conversions as STK and its modules. OD Tool Kit 3.0 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. OD Tool Kit 3.0 can produce results for satellite orbit parameters by processing one satellite at a time or multiple satellites simultaneously.
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.
Formerly released under the name STK/OD, the product has been renamed to OD Tool Kit to more truly reflect the fact that it is a stand-alone product, not an add-on module to STK. Particular care has been taken to ensure that regression tests to STK/OD 2.0 are satisfied, that STK/OD 2.0 scenarios will load and run in OD Tool Kit 3.0, and that STK/OD 2.0 restart files will initialize in OD Tool Kit 3.0.
New Features
New features introduced with this release include:
TDRS processing capabilities
Simultaneous orbit determination of multiple Tracking and Data Relay Satellites (TDRS) GEO orbits and multiple LEOs and/or MEOs is enabled with the implementation of capabilities to process 4-legged range and 5-legged Doppler measurements for NASA's Tracking and Data Relay Satellite System (TDRSS). NASA's associated Bilateral Ranging Transponder System (BRTS) range and Doppler measurements can also be processed to perform orbit determination on each TDRS separately, or on all TDRS simultaneously, by fusing BRTS measurements with TDRSS measurements. Radio signals for measurements in the same round-trip link are all generated by the same atomic ground clock, with the effects of clock phenomenology and relativity subtracted out.
This benefits NASA programs and others that use TDRS for their tracking.
GoodingAnglesOnly IOD
A GoodingAnglesOnly method has been added to Initial Orbit Determination (IOD), providing the capability to estimate the position and velocity of a spacecraft from three pairs of angles measurements and their tracking platform positions. Tracking platforms may be ground stations or spacecraft with tracking sensors. Angle measurements can be used from one, two or three distinct tracking platforms.
This method is useful in, among others, cases in which facilities collect angles without range data, e.g. in optical tracking applications.
Updated force modeling
The orbit propagation model now includes:
- Relativistic gravity effects
- Ocean tide perturbations
- Updated solid earth tide perturbations
- Plugin force model.
These force model enhancements are important for Geodesy applications and others, such as LEO military programs, that require highly accurate force modeling in the orbit propagator. The plugin capability lets users define body-specific customized force models for solar pressure and drag.
Smoothing across multiple filter runs
Users can now run the smoother over multiple sets of data output from the filter. The smoother can be run across the time period of interest, even if it is broken up into multiple OD filter runs.
Reference ephemeris for residuals
The capability to compute residuals against a reference ephemeris has been added. This will make it easier to calculate facility biases.
Improved filter controls
Numerous improvements have been made to make OD Tool Kit more user friendly. These include better control over state space, times of execution, and output file names and locations, as well as faster generation of reports and graphs.
The attributes Filter.ProcessControl.StopTime and Filter.ProcessControl.TimeSpan are now completely independent and do not interact with each other. Prior to this release, when StartMode was set to AutoReStart and StopMode was set to TimeSpan, the StopTime would automatically be incremented by the TimeSpan with each filter execution. Now the StopTime remains unchanged until specifically changed by the user with the StopMode = StopTime option.
GPS navigation solutions
GPS receiver-generated navigation solutions have been added as a tracking data type. This benefits users that do not downlink the pseudorange measurements from their own GPS receivers but do downlink the ECF position generated by the receiver.
Greatly improved means of obtaining attribute information
The previous version provided a means of retrieving the fully qualified name (path) for an attribute, which could be copied and pasted into a user's script. OD Tool Kit 3.0 adds other information, including data type, units and limits:
All of this can be easily obtained by right-clicking on the attribute in the Properties dialog.
In addition, you can explore the OD Tool Kit Attribute Hierarchy in the Help without running OD Tool Kit.
The tree that lets you navigate through the attribute hierarchy takes a few seconds to load.
Improved simulation controls
Several changes improve the simulation of tracking data. Through the custom tracking scheduler, tracking data can start and stop at arbitrary times, and the tracking data rate is now independent of the simulator's time grid:
- Two utilities, SaveObservationIntervals and LoadSimulationIntervals, allow the custom tracking schedule to be loaded with exactly the same tracking intervals as detected in live data.
- A new utility, SimulatorScheduleEditor, provides the capability to easily change the true/false flags in the custom tracking schedule.
- GenSimSchedule30 provides the capability to identify previously saved STK facility objects with OD facility objects when creating a new STK scenario. This feature allows the analyst to create complex access constraints for facilities, such as a phased array radar, and then reuse those objects in subsequent analyses.
- GenSimSchedule30 allows the selection of an entire STK scenario in lieu of building a new scenario, which should provide some configuration control over complex analyses.
- GenSimSchedule30 now retrieves the minimum elevation angle from the OD facility object and presents that as the default minimum elevation in the GUI.
- Both GenSimSchedule30 and GenSimSchedule will reset STK scenario stop and start times to agree with the OD Simulator start and stop times.
Facility location estimation
OD Tool Kit has added the capability to estimate facility location, providing the options to estimate either latitude and longitude, or latitude and longitude and height. The implementation assumes the location error to be an initial condition error, which is sufficient for fixed platforms with location errors, but not suitable for mobile platforms.
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 |
| 04907 | Scrolling the message window no longer causes the filter to stop running. |
| 05251 | A flexible time grid was added to the Custom Tracking schedule. The measurement time grid for the Custom Tracking exclusion intervals is now asynchronous with the Simulator time step grid. This change only alters the simulated measurement output grid times (from prior versions) when Custom Tracking Schedules are used. It does not change the output grid times when Custom Tracking Schedules are not used (which is the default). |
| 05580 | "No More Obs" is no longer reported twice at the end of a filter run. |
| 05620 | An earlier problem involving the incorrect display of filter data under certain conditions in dynamic reports and graphs has been corrected. |
| 05720 | Histogram data is no longer reset following a pause event. Histogram reports and graphs for a run that was paused (or paused several times) now contain data for the entire run, rather than just data since the last pause event. |
| 05752 | The maximum number of restart records can be changed at each filter restart. |
| 05858 | Problems associated with restarting the filter within a maneuver interval were fixed. Previously, the estimated mass state was not always handled correctly following the restart. |
| 05860 | Protection has been added to prevent restarting from a changed state. |
| 07123 | Several changes were made to make the application more stable, including: (a) limiting user actions while processes are running or reports or graphs are being generated, and (b) providing conflict control for concurrently running OD processes and reports or graphs. In these situations the processes may appear to stop running; however the pause is temporary, until the conflicting process completes. |
| 07198 | AGI servers now poll multiple sources of solar flux and geomagnetic index data to provide new observed daily flux and 3-hourly Kp/ap data on a daily basis. This data is available to users to download from AGI servers. A source for 3-hourly Kp/ap data that reports more frequently than once per day has not been found. |
| 07286 | Millidegrees are now available from the unit picker in the OD Tool Kit user interface. |
| 07705 | The graph style editor has been changed to provide the user with control over the way legends appear in customized graphs. The legends now appear in sorted order. The order of objects in a legend entry (e.g. facility name before measurement type) can be changed by changing the order of the list in the Group-By-Fields in the graph style editor. |
| 07630 | If you set the Display option to false on a data product for a graph, the graph display no longer persists. |
| 08308 | New fields have been added to the TrackingData OLEDB Table for displaying and reporting RA and DEC epoch and coordinates and
aberration flags:
|
| 08691 | If the user changes the file type in a file dialog box, then the extension to the specified file is automatically changed. |
| 08799 | The IOD observation list is no longer restricted to one pass. Observations spanning multiple passes are available, and user only gets a warning message if they are too far apart. |
| 08894 | A previous limitation involving the output of the Save Observation Intervals tool when dealing with Space-Based trackers has been resolved. |
| 10481 | A typographical error in the HPOP Gauss-Markov decay equation has been corrected. The error only affected how a Gauss-Markov parameter was varied during a single integration step. |
| 10538 | Filter stop time and filter duration are now independent attributes. |
| 10729 | The Name field for each maneuver can now be added to customized maneuver reports. |
| 11033 | The Smoother attributes IntervalLength and IntervalOverlap have been moved to the Smoother ProcessControl scope from the main Smoother scope. Backwards compatibility code has been added to support the transition from STK/OD 2.0 to OD Tool Kit 3.0 scenarios. |
| 11082 | Users can no longer exit OD Tool Kit while a filter is paused. They must either stop the filter run or complete the run before exiting. This ensures that the filter is in a valid state while exiting or saving the scenario. |
| 11144 | This version provides a new capability to extract reported data from the database and construct a text report directly, with limited format control. See the attached instructions on using the State File Dumper Utility. |
| 11147 | Some of the HTML pages have changed in appearance in order to provide a uniform look and feel. These changes do not affect the underlying scripts. |
| 11152 | Report styles have been provided for Avg Sat Force Model Biases, Avg Tracker Biases, and Avg Transponder biases. Additional
summary statistics for median, min and max have been added to aid the analyst in evaluation of mean.
These calculations require more processing than other report styles, and report generation will appear to stop while these calculations are performed. |
| 11214 | The current install includes the file AgAsSGP4EphFile.exe, a utility that takes a file of TLEs and either generates a file of SSC numbers and TLE epochs to be used for user selection of a specific TLE, or generates an STK .e file using a selected TLE. This file was missing from the install CD for the previous release. |
| 11390 | The old simulator attribute TrackerList has been replaced with a new attribute TrackingStrandList. Tracking strands consist of the tracker object (the entries in the old TrackerList) and one or more other objects, where one link in the strand is usually a wildcard (*) indicating the currently tracked satellite. Thus, if the you had an entry in the old TrackingList of (Basline.COOK_A), your new TrackingStrandList will contain (Basline.COOK_A - *). This change was made to allow for better simulation control over more complicated measurement types such as TDRS 4-legged range, where a tracking strand might look like (WhiteSands.Antenna1 - TDRS4 - *). The SelectedTracker attribute in the custom simulation schedule has likewise been replaced with SelectedTrackingStrand. If the tracker in a tracking strand is a GPS receiver, then the tracking strand will have the form of (CHAMP.BlackJack - GPS), where GPS is a fixed string indicating an arbitrary satellite in the GPS constellation. |
| 11531 | The Programmer's Library (PL) license dependency of the Initial State Tool for generating initial conditions from TLEs has been removed. |
| 11628 | The solar flux inputs, contained in the file ap.dat, for the IRI 2001 ionosphere model are now updated daily and are available for download from ftp.agi.com. The input data for the IRI 2001 model is stored under the DynamicEarthData directory. |
| 11631 | When no scenario is loaded, OD Tool Kit will no longer save Report or Graph styles to the main user's directory by default. OD Tool Kit now saves to the user's Styles subdirectory by default. |
| 11635 | The Attribute Information dialog now displays the full path to the selected attribute. |
| 11671 | If an STK/OD 2.0 scenario is run under OD Tool Kit 3.0, the progress bar may appear to overwrite the button displaying the message viewer status. This problem can be corrected by deleting the workbook (*.wsp) for the scenario. |
| 11790 | There are two new flags for residual editing, associated with TDRS 4-Legged range data; these are FR and ND, and are a consequence of settings in the MeasurementStatistics for a TDRS facility. ND will reject range data when there is no Doppler measurement present, and FR is the forced rejection of the first N measurements in a pass (not counting ND data). Both of these flags and options are a consequence of the way that a TDRS facility reports tracking data before the tracking loops have locked on. |
| 11806 | The default for Smoother IntervalLength has been changed to 60 days from 7 days. |
| 11816 | Users can no longer use the SaveAs, Import and Export options while a filter is paused. |
| 11847 | The default for Satellite.ForceModel.Drag.DensityRatioIncreaseThreshold is now 1.0 rather than 0.1. |
| 11851 | The Instant Maneuver HTML Utility "InstantManeuverSet" has been added to create series of maneuvers for a satellite, equal in magnitude and uncertainty and evenly spaced in time. |
| 11959 | OD Tool Kit 3.0 will restart or autorestart from an STK/OD 2.0 restart file, supporting continuing operations. Due to changes in the restart file structure, a 3.0 restart file cannot be read with STK/OD 2.0. Restarting a 2.0 scenario in 3.0 will usually result in a warning: "Restart state from the previous version successfully imported, resetting restart file," which indicates that the restart file only contains records generated with OD Tool Kit 3.0, and that those generated with STK/OD 2.0 have been discarded. The original 2.0 restart file is saved to a *.bak file for recovery purposes. If the user anticipates going back to 2.0 for any reason, this *.bak file should be archived. |
| 11988 | The model and total atmospheric density reported in the satellite state data provider were corrected. In prior versions, the density was always reported at perigee. |
| 12122 | Previously the Initial State Tool would only load the satellite object at the epoch time of a TLE. Now the user can select any epoch and the SGP4 propagator will predict the TLE to that time and create the initial state at that time. |
| 12223 | In STK/OD 2.0 the user could attach a reference ephemeris to a satellite object and then set Estimate to true. The scenario would remember the hidden file name. However this caused unnecessary error messages when the ephemeris file had been deleted or moved. In OD Tool Kit 3.0, if the Estimate flag is set to true then the reference file name is not saved. Similarly, when a 2.0 scenario is loaded, the setting of the Estimate attribute is checked and any hidden reference ephemerides are removed. |
| 12272 | The current version corrects a problem in the CreateEphFileTool that resulted in an extraneous ephemeris point being added to the generated ephemeris file when the start time of the ephemeris was selected to be different than the start time of the run file. |
| 12279 | The capability to override the runfile name is changed. Now when the user overrides the runfile name the simrun, filrun and smtrun file names are grayed out in the Object Properties dialog. Further, the user is given control of the directory where the override runfile is stored. As a consequence, scripts that utilize the Scenario NewRunName property must now use NewRunFilename instead. NewRunFilename includes a full path to the overridden run files. |
| 12400 | OD Tool Kit nominally determines the GPS receiver id associated with a RINEX observation file from the file header MARKER NUMBER id or MARKER NAME id, if the id is numeric, and either of these records is included in the header. Otherwise OD Tool Kit will determine the id from the RINEX filename if the filename is of the form Satnnn_xxxxxx.zzz, that is, beginning with "Sat", followed by series of digits "nnn", followed by underscore "_", followed by the rest of the filename and extension. In this case the digits "nnn" define the receiver id. Prior to this version, the text "Sat" was case-sensitive. Now it is not, and you may use "Sat", "SAT", "sat", etc. |
| 12402 | The Rinex convention for observation files calls for the file type extension to be of the form *.yyo, where yy is a 2-digit year number. The user can add these extensions for GPS Rinex data through Tools -> Options -> Plugins, and add to or replace the default extensions. |
| 12445 | A GPS Nav Solution measurement plugin with the suffix .navsol as the default extension has been added. The user can edit this from the Tools->Options->Plugin settings for the GPS Nav Solutions plugin. |
Transition Matters and Unresolved 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 OD Tool Kit, 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 OD Tool Kit:
- Loading Scenario workbooks which have the scenario name followed by a .wsp extension may not work properly in some situations, for instance, if HTML pages referenced by that workbook have been moved or removed. By updating the windows when loading and resaving the scenario, the problems should be corrected. Alternatively the user, before opening the scenario, may manually delete the scenario .wsp file using Windows Explorer.
- Currently the simulator does not simulate the effects of geopotential errors, but the filter error covariance does account for geopotential errors. This problem does not affect the processing of real data. If one looks carefully at the filter response to processing simulated data, the error magnitudes of filter orbit errors are smaller than is indicated by associated orbit error root variances.
- As currently defined, the Atmospheric Density Estimate, Solar Radiation Pressure Estimate, Transponder Bias and Ballistic Coefficient graph styles do not generate sigmas for simulated data. However, if you generate one of these types of graphs with a simulation file as input, the legend will contain references to sigmas, and a straight line purporting to represent sigma values will appear in the graph. These should be ignored, since there is no sigma data in the input file. To remove the spurious references and the line from the graph, right-click on the graph, select Properties, select the Series tab, select the series to hide and uncheck the 'visible' box.
- Help on the OD Tool Kit Report Viewer is not available directly from that interface. However, access to the Crystal Reports Help system is provided via the OD Tool Kit Help system. In the Contents tab, select Reports & Graphs -> Reports -> Static Reports, and click on the link to Crystal Reports.
- For optimal performance, only single-table reports should be generated. Graph styles support a single table only.
- Troposphere range refraction error is currently modeled in the filter, but deviates are not applied by the simulator. Consequently, filter range residual ratio histograms derived from simulated range data will be somewhat peaked, when compared to the Gaussian density function. However, troposphere range refraction is modeled in both the filter and the simulator.
- The control of GPS measurement types in the current release is subject to certain limitations. The only valid measurement types for simulation are CA Pseudo-range, P1 Pseudo-range and P2 Pseudo-range. The selection of measurement types must be made in the satellite attribute MeasTypes. The filter can model pseudo-range exactly as simulated, which is the simplest case. However, the filter can process pseudo-range in different ways, as single differencing (SD), and/or as dual-frequency (DF) corrected pseudo-range. These alternative methods require more manual input by the user, requiring that MeasTypes have one setting to run the simulator and another to run the filter. In addition, various combinations of pseudo-range cannot appear in MeasTypes simultaneously; see the online Help system for the matrix of valid combinations.
- If you create your own tracking data providers, it is necessary to update them, since the Measurement Provider Script interface
has changed. Otherwise, the old tracking data provider scripts will not work. This change was made in order to accommodate
the new GPS measurement types (as well to support future multi-leg measurement types). Reference the several sample scripts
in
as well as OD Tool Kit Help for examples and descriptions.<Install Directory>\STKOD\AppData\Scripts - If you load a scenario saved with STK/OD version 2.0 or a prior version, and then save it, it will be saved as an OD Tool Kit version 3.0 scenario and cannot be loaded back into prior versions.
- The addition of the ground-based range representation options OneWay and TwoWay have a potential impact on running IOD. If you read an IOD object from an STK/OD version prior to 2.0, in order to run the IOD process you must be using the OneWay representation. Since the default in OD Tool Kit 3.0 is OneWay, this will not be an issue unless you specifically change the value to TwoWay.
- As part of transitioning OD Tool Kit scenarios from one version to the next, you should pay special attention to files being used for EOP, solar flux and ionosphere modeling. These files are specified in the EarthDefinition section of the scenario attributes. If you load a scenario created in STK/OD 2.0 or a prior version into OD Tool Kit 3.0, the files specified in the older version will be found and will continue to be used. While this is desirable for some cases, such as performing regression tests, you will probably want to update these file locations to point to files associated with OD Tool Kit 3.0. These newer files are the ones which will be updated by the Update Data Files tool in OD Tool Kit 3.0.
- 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 reports styles created by the user. Before attempting to use a report style generated with a STK/OD 2.0 or a prior version with OD Tool Kit 3.0, 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 OD Tool Kit. 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.
- Since STK/OD 2.0 graph styles are not compatible with OD Tool Kit 3.0, a tool has been provided to convert your 2.0 custom graph styles to 3.0 graph styles. The tool is called OD_Gph_Update20To30.exe, and is found in your install area under AppData\Scripts. This tool will convert all 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 2.0 graph styles are not overwritten.
- AGI's ftp server name (formerly ftp.stk.com) is now ftp.agi.com.
- IOD Herrick-Gibbs SelectedMeasurement string lists saved in scenarios created in prior versions are obsolete in OD Tool Kit
3.0, because of two 3.0 changes:
- The "UTCG" string has been added to the string, and
- Multiple passes are now displayed, which changes the displayed "reference time".
For OD Tool Kit 3.0, two elements of the MeasurementHistory database table have been renamed to be more consistent with other database tables in OD Tool Kit and two elements have been removed. Specifically, the Num Trackers and Num Vehicles elements have been removed, and Tracker IDs and Vehicle IDs have been renamed to Tracker Name and Satellite Name, respectively. If you have created custom report styles that use the renamed elements, Crystal reports will provide you the opportunity to map the old element names to the new element names during the Verify Database operation. The ability to see all objects involved in the computation of the measurement value is now supported through two new elements, Tracking Strand and Tracking Strand Full. The Tracking Strand element lists all components of the tracking strand with the exception of the satellite of interest which is designated by *. The Tracking Strand Full element lists all components of the tracking strand.
Unresolved Issues Affecting the Current Release
The user should be aware of the following limitations and unresolved issues affecting OD Tool Kit as of the date of this release.
While the filter is running, the user can view dynamic time and measurement update reports for each GPS receiver in the scenario. These reports show estimates to clock phase and frequency, and the measurement reports also show GPS measurement residuals.
Residual information for GPS measurements is found on both the GPSReceiver dynamic measurement update report and the Satellite dynamic measurement update report, except, as discussed below, that SD residuals are not shown on the GPSReceiver dynamic measurement update reports.
In the current release, however, these GPSReceiver dynamic reports are only populated when the filter processes measurement types that cause clock phase and frequency to be estimated, namely, CA, P1, P2, and DF. If you are processing DF SD or CA SD measurement types, there is no clock estimate and these dynamic reports are not updated. Regardless of the measurement type, the user can still view the GPS residuals by viewing the dynamic measurement update report for the parent satellite. Our goal is to show GPS residuals on the GPSReceiver dynamic measurement update reports regardless of the GPS measurement type.
Changes Introduced in Version 3.0.2
The following information applies to OD Tool Kit version 3.0.2.
Capabilities Added and Issues Resolved in Version 3.0.2
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 Version 3.0.2 | |
|---|---|
| Tracking No. | Description |
| 12794 | The SortUTDFObsFile utility has been updated to make single/multiple file extensions consistent. Previously, the single file utility sorted files of type .bin, .utdf and .trk, while the multiple utility sorted files of type .bin, .dat and .utdf. The extensions have been made identical for both utilities. |
| 13405 | An error in the application of drag sigma during the density initialization period has been corrected. |
| 13417 | A problem with the computation of random deviates in facility locations has been corrected. This problem was most apparent when uncertainties in the East, South and Altitude directions differed significantly. |
| 13458 | If a satellite involved in a simulation had an epoch different than that of the start of the simulation and that satellite also had a GPS Receiver on it with an epoch different than that of the satellite and the simulation was not set to produce GPS measurements, the simulator would terminate abnormally. The problem would occur when an attempt was made to transition the satellite state to the start time of the simulator. It was caused by a failure to create a single satellite state for propagation due to the difference in epochs between the satellite and GPS receiver. That problem has been corrected. |
| 13459 | The loading of selected tracking strands in the TrackingStrandList of the simulator object has been fixed. |
| 13524 | An application error occurring during smoothing for the case where a satellite has two finite maneuvers, one of which is inactive, which span the end of the filter run has been corrected. |
| 13529 | An error in the computation of partial derivatives during the estimation of facility locations when only latitude and longitude are estimated has been corrected. |
| 13556 | The filter stop time is now properly initialized for cases where a stop time is selected as the stop mode. |
| 13563 | A reversal of data between the Julian Day Number and Minutes after Midnight fields in the finite maneuver summary data provider has been corrected. |
| 13589 | Numerical partials are no longer being computed for BRTS range and BRTS Doppler. |
| 13590 | The tropospheric effect on 4 legged range and BRTS range measurements has been added to the simulator and filter outputs and can now be reported. |
| 13591 | The reported values for the tropospheric contribution to the 5 legged Doppler and BRTS Doppler models have been corrected to be in Hz instead of m/s to be consistent with units used for observation and residual reporting. |
| 13680 | An error in the validation of the filter stop time when the filter was configured with a stop mode of stop time has been corrected. |
| 13828 | This release corrects the data provider and measurement model for BRTS Doppler, to add the manipulation of the pilot tone for TDRS 8, 9 and 10. |
| 13891 | This release fixes Sat and Tracker IDs in the Tropo Meas Corrections Report. |
| 13909 | A problem in which Herrick-Gibbs IOD apparently failed to check for a valid pass number prior to using it in an error message has been corrected. |
| 13946 | This release adds a new bistatic range measurement model. Normal round trip range via a transponder is supplemented by a second downlink to another facility. The uplink errors are the same on both paths, and the transponder for the second downlink is separate, as are all of the downlink delays and facility range bias. The measurement is tagged with receive time at the new facility. |
| 13956 | Previously, the State History Dumper utility would dump one time point or it would dump every time point. A new option added in this release allows you to dump from a specified start time to a specified stop time. |
| 14044 | An error in the reporting of covariance elements with mixed units via the State History Dumper utility has been corrected. |
Unresolved Issues Affecting Version 3.0.2
The user should be aware of the following limitations and unresolved issues affecting OD Tool Kit as of the date of the version 3.0.2 release:
| Unresolved Issues in Version 3.0.2 | |
|---|---|
| Tracking No. | Description |
| 13198 | In a custom graph, the initial date/time is always included in the X-axis label, even if you create a graph where the X axis is not time. |
Changes Introduced in Version 3.0.3
The following information applies to OD Tool Kit version 3.0.3.
Capabilities Added and Issues Resolved in Version 3.0.3
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 Version 3.0.3 | |
|---|---|
| Tracking No. | Description |
| 06621 | A new GPS measurement type has been added, where CA pseudo range measurements are formed by transponding the GPS signal through the tracked satellite to a GPS receiver on the ground. |
| 12456 | The ODTK Least Squares capability now supports processing TDRSS measurements (4L Range, 5L Doppler) for a user satellite. |
| 12596 | Several messages have been changed from "errors" to "warnings", particularly those triggered when a scenario is generated on one computer and then loaded by another user on another computer. |
| 13102 | The GenSimSchedule and GenSimSchedule30 scripts have been updated to support very small intervals, on the order of a fraction of a second. (Previous versions encountered problems with small intervals near month boundaries.) |
| 13198 | A new checkbox has been added to the graph designer for specifying whether to append start time to the X axis label and indicate the time of first point annotation in the upper right corner of the graph. |
| 13986 | OD Tool Kit now can display One-Way Bistatic Range and 2-Legged GPS CA Pseudo Range residual dynamic graphs. |
| 14333 | A problem in the setting of the initial covariance of estimated facility locations has been corrected. The problem only affected scenarios where non-zero a priori correlations betweent the positional components were used. |
| 14435 | In OD Tool Kit 3.0.2 the constant transponder bias in the Transponder Bias report was incorrectly reported. The nanosec value was 1000 times too small. This is fixed in version 3.0.3. |
| 14459 | Prior to OD Tool Kit 3.0.3, propagating a satellite twice ending within a FinMan span could cause an abort. This has been fixed. |
| 14628 | A problem in the computation of the centroid of instant maneuvers specified via an acceleration history file has been corrected. This problem was evident for maneuvers whose time frame was significantly different than the default epoch time of 1 Jul 2004. |
| 14730 | A problem with the filter running in an infinite loop if the a priori covariance on an estimated facility location has a negative eigenvalue has been corrected. An error message is now printed to the message window indicating the facility containing the bad data, and the filter is stopped. |
| 14733 | A problem in the numerical integration of mass flow rates for finite maneuvers specifed using an acceleration history file containing mass rate information has been corrected. This problem resulted in small errors in the computed maneuver mass loss. |
| 14855 | A problem in the computation of the Julian Day Number which led to incorrect results at day boundaries in data providers related to reports and graphs for finite maneuvers and transponder states has been corrected. |
| 15171 | The Residual Summary Report calculation of residual statistics has been corrected. |
| 15217 | The Residual Summary report style incorrectly counted some rejected residuals in the total of accepted residuals, which caused erroneous mean and RMS values. The error in the report style has been fixd, and all statistics are based on accepted residuals. |
| 15229 | A problem has been corrected with LS partial derivatives. LS has also been extended to process (using Numerical Perturbations, set as an LS attribute) any measurement in version 3.0.3 including TDRSS and GPS measurements. New reports were added to report LS Residuals for GPS and TDRSS cases. |
| 15251 | The inclusion of ground based measurement biases in the filter state when the associated facility objects were not selected as part of an explicit tracker list has been corrected. This should result in small filter states and therefore shorter filter/smoother run times in cases where the filter TrackerList is used. |
| 15387 | The capability to generate a simulated truth ephemeris for a satellite object using a reference ephemeris has been reinstated. |
| 15481 | New graph styles and report styles have been added to support GPS and TDRSS data processing. |
| 15534 | Various improvements were made to the report style editor. The name of the file being edited now appears in the windows title, the New button now works properly, and Save As now keeps the editor open on the "saved as" file. |
| 15851 | New Crystal Reports DLLs have been added to print data in scientific notation. The Atmospheric Density Total report has been converted to scientific notation as an example. |
| 16092 | An error in the additive deweighting of the filter covariance based on unmodeled acceleration process noise associated with satellites has been corrected. In prior versions, the specified process noise was added with each time update regardless of the span of the time update. This lead to over-inflated covariance in the case of dense tracking data. The current version corrects this issue by associating a time interval with the specified process noise and scaling the specified process noise based on the ratio of the time update span over the specified time interval for each time update. |
| 16096 | An ad-hoc solar pressure process noise model has been added which allows the specification of acceleration uncertainty in two directions orthogonal to the sun-to-satellite direction. This new capability can be used to keep the covariance open in cases where significant solar sailing effects, which cannot be modeled by the current spherical solar pressure model, are present. It should be noted, however, that for cases where such effects exist and are deterministically known, orbit accuracy can be improved by modeling the solar sailing effects with a custom force model plugin. |
Unresolved Issues Affecting Version 3.0.3
The user should be aware of the following limitations and unresolved issues affecting OD Tool Kit as of the date of the version 3.0.3 release:
| Unresolved Issues in Version 3.0.3 | |
|---|---|
| Tracking No. | Description |
| 07630 | If Display is set to false on a data product for a graph, the graph is displayed anyway. |
| 11118 | Data limiting does not work for singly differenced residuals. |
| 14875 | Currently least squares does not use maneuver information if it is provided in the satellite object. |
Online Help Resources
The current version of OD Tool Kit is shipped with the following online help resources:
- OD Tool Kit Help System
- Context Sensitive (F1) Help
- Printable (PDF) Tutorials and Technical Documents
The OD Tool Kit Help System
The OD Tool Kit 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 textbox. 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 recur 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
In STK/OD 2.0 we added help buttons 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 OD Tool Kit, including a set of tutorials (Getting Started with ODTK), a scripting guide and documents explaining the mathematical and scientific background of OD Tool Kit. To access these documents, go to the manuals page.