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STK Certification RJ Michalsky Yes you can become a “Rocket Scientist”. Agenda. Program Background STK Cert Content Astronautics Primer Installation & STK Basics File Management STK Tools STK Pro Chains & Constellations Connect STK/AVO Scenario Development. Program Background. Intent
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STK CertificationRJ MichalskyYes you can become a “Rocket Scientist”
Agenda • Program Background • STK Cert Content • Astronautics Primer • Installation & STK Basics • File Management • STK Tools • STK Pro • Chains & Constellations • Connect • STK/AVO • Scenario Development
Program Background • Intent • To provide a rigorous measure by which an individual can demonstrate STK product knowledge • Statistics • Program started in 2000 • Almost 300 have passed the exam • 15 to 60 hours to complete • Content • Self study • 30 days to submit answers • Cost • $495 fee
Program Basics • Submissions • Answers to multiple choice questions • Submit scenarios / connect script / avi movie • Rewards • Polo shirt /certificate • Adulation of your peers • Future • Due for an update post STK 7.0 release • Beyond • Possible Advanced level program • Possible expansion for other AGI products
Astronautics Primer • Key Points • This section is about 10% of the total test. • HTML-based Astronautics Primer document installs with STK • Content of this section of the test is general astronautics information NOT STK specific. • All information needed to answer questions can be found in Astronautics Primer • “Understanding Space” textbook is the reference • Jerry Jon Sellers (Author)
Installation & STK Basics • Key Points • This section is about 20% of the test • This section tests the user’s familiarity with STK and STK/Pro functionality and use. • Reports • Access • Databases • Propagators • Sensors • Constraints • Great Arc Vehicles
Reports This section will answer… • What is a “Report” in STK? • How do I generate a report on an object? • How do I create a report that has only the data that I want? • How can I name these custom reports?
Reports • What is a “Report” in STK • An STK “Report” generally retrieves information about a single object • Aircraft, satellite, receiver, transmitter etc. • Extract information like… • Object position and orientation in various element types and coordinate systems • Lighting times • Satellite Orbital elements • Satellite Pass information
Access This section will answer… • What is “Access” in STK? • How can I use STK to determine if two satellites can see each other? • How do I create an access report that has only the data that I want?
Access • What does “Access” mean? • “Access” is STK’s geometry engine. • Unlike “Reports” it can perform analysis and generate information on the geometric relationship among many objects.
Databases • In this section we will answer • What databases are available? • How do I use STK’s databases • Can I add my own databases to STK?
Databases • What databases are available with STK?
Propagators • This section will answer • What is a Propagator? • How do I define my satellite’s state vector? • How do I change the model STK is using to propagate my satellite?
What is a propagator? • Within STK a propagator is simply a tool that is used to generate position information as a function of time for an STK object. • STK offers several types of propagators for satellites • STK allows users to modify the model that it uses to propagate the satellite
Sensors • In this section we will answer… • What is a sensor in STK? • Which types of sensor models are available? • How do I visualize sensor footprints in 2D and 3D?
Sensors • What is a sensor in STK? • Models some of the behavior of a physical sensor • Radars • communications antenna arrays • electro optical • Infrared • hyper spectral Note: These base models are purely geometric. Higher fidelity models for these types of sensors are also available in advanced modules of STK.
Sensors • Sensors also provide a geometric tool • Object that has useful properties… • Inherits position information from parent object • Can be uniquely oriented with respect to Parent including… • Targeted • Fixed on system • Pointed by external file • Parent object includes all moving STK objects and facilities • Satellites, Aircraft, Ships, Ground Vehicles, Facilities.
Constraints • In this section we will answer… • What is a constraint in STK? • What kind of constraints are available? • How do I use constraints?
Constraints • What is a constraint in STK? • Constraints are a term used to limit what is considered to be a valid “access” • For instance a sensor may have line of sight to a target, meaning that the earth is not in the way, but if the target is not in daylight that sensor may not be able to “see” the target.
Constraints • What kind of constraints are available? • Basic – Simple geometry. Some examples include… • Elevation angle, min & max • Angular Rates, min & max • Range, min & max • Temporal – Time based, for example to model daily shifts. Some examples include… • Start & Stop, times of day • Durations, min & max • Intervals, defined by file • Sun – Lighting and Geometry. Some examples include… • Sun Elevation, min & max • Sun Exclusion, min & max • Lighting, Umbra, Penumbra, & Direct Sunlight • Dozens of others to model very specific behavior. Some constraints are sensor specific. For example Transmitters & Receiver access can be constrained on bit error rate.
Great Arc Vehicles • In this section we will answer… • What is a Great Arc Vehicle? • How do I add a waypoint to a vehicle?
Great Arc Vehicles • What is a Great Arc Vehicle? • Great Arc Vehicles refers to the class of vehicles who’s position can be defined along the surface of the earth by waypoints connected by an line on the surface of the earth. Such a line is referred to as a “Great Arc”. • Great Arc Vehicles in STK include, Ground Vehicles, Aircraft, and Ships. Internally STK handles each of these vehicles in a similar way but each has it’s own default behavior (e.g. ships always move at 0 altitude, where aircraft default to 10000ft, or 3048 m)
Great Arc Vehicles • How do I add a waypoint to a GA (Great Arc) vehicle • Manually enter waypoints • Click out path on 2D map • Shift-Click out path on 3D map • How do I edit a waypoint on a GA Vehicle? • Manually edit waypoints • Click out changes on 2D map • Drag waypoints on 3D map in 3D edit mode
File Management SAVE
File Management • Each object saved separately • Almost all files are ASCII based and human readable • Saved object files can be imported into other scenarios
STK Tools • Key Points • This section is about 5% of the test • This section tests the user’s familiarity with Key STK Tools. • Strip Charts • Dynamic Display • Solar Panel Tool • Exporting Data Files • Creating VDF Files
Strip Charts • Strip Charts behave very similar to Reports. • Choose the strip chart tool and choose a report. • These charts can also be customized. • Strip Charts are updated as a scenario animates
Dynamic Display • Dynamic Display areas behave very similarly to reports and strip charts. • Choose the dynamic display tool and choose a report. • These displays can also be customized. • Like Strip Charts Dynamic Display areas update as a scenario animates.
Solar Panel Tool • The Solar Panel tool estimates the power generated by a solar panel • Leverages STK AVO to count the number of pixels of solar panel that can be seen from the sun • By counting these pixels it can estimate the exposed solar panel area and predict performance • This technique accounts for highly complex phenomena like satellite self obscuration and obscuration by another satellite or celestial body.
Solar Panel Tool • To Access the Solar Panel Tool right click on a satellite and choose “Solar Panel Tool”.
Exporting Data Files • Exporting data Files from STK allows you to save the ephemeris for a vehicle (position as a function of time) in a properly formatted “.e” file. • These files can easily be imported into other objects in the same scenario or in a different scenario.
Exporting Data Files • To export a data file simply highlight the object, select file -> Export -> Data File as shown.
Exporting Data Files • Then simply select the type of file and the save location. • Advanced users can control the coordinate system and time step from this location as well.
Create VDF File • Creating a VDF file is similar to creating a Data File. Select the Scenario -> open the file menu -> Select Export -> and choose AGI Viewer File. • New users can simply press save to output an AGI viewer file. Advanced users have many more options available to them to optimize exported file size.
STK Pro • Key Points • This section is about 7% of the test • This section tests the user’s familiarity with the STK Professional Module. • The necessary background for this section was covered in the STK Basics section
Chains and Constellations • Key Points • This section is roughly 3% of the test. • This section tests user’s familiarity with the STK chains module including use of the following STK objects • Chains • Constellations
Chains and Constellations • Access tool within STK allows users to determine point to point line of site. • STK Chain and Constellation objects allow users to establish long logical combinations of “accesses” • When can (“A” see “B”) and (“B” can see “C”) • and to group a set of objects together for analysis. • When can “A” see (“B” or “C” or “D”)
STK Connect • Key Points • This section is roughly 4% of the test. • This section tests user’s familiarity with the STK interface to external programs • Intro • Input Options • Configure objects • Extract analysis results • All commands are documented in the STK Help system
STK Connect • Intro • Extremely important capability for many analysis environments and critical to operations using STK • Uses strings sent into STK to manipulate STK • Strings can be passed across an TCP/IP socket or using the Microsoft Component Object Model (COM)
Input Data • “New / Scenario Test” • Creates a New Scenario • “Graphics */Satellite/Satellite1 Basic Show Off” • Removes “Satellite1” from the STK graphics displays • GetReport */Satellite/Satellite1 “J2000 ECI Position Velocity” • Retrieves J2000 ECI Position Velocity report
STK/AVO • Key Points • This section is roughly 5% of the test. • This section tests user’s familiarity with the STK 3D Graphics Windows • 3D Properties Windows • Viewpoint Control • View-paths • Videos • Imagery
3D Window Properties • Look through the 3D Graphics Window Properties by selecting the 3D graphics window and pressing the properties button. • Experiment with each option available on each tab to get a good feel for the window’s options • Each of these capabilities is covered in depth during the STK Advanced Training