Scenario Basic Time
Analysis Period
The scenario analysis period defines the epoch and the start and stop times of your scenario in established units. The epoch serves as a reference for all other times in the scenario. The time and date of the epoch correspond to zero epoch seconds. The analysis period defines the general time span (a range of several hours, days or weeks) for analysis. If you change the start and stop times here, STK automatically propagates the orbits of all satellites in your scenario over the specified time period. For more information on the options available for setting the start, stop, and epoch times, see Time Options.
Formats for all time-related fields are dependent upon the time units set at the scenario level.
Animation
Scenario animation properties control the animation cycle, animation step definition, and the intervals between refresh updates in the 2D and 3D windows. Enter the animation Start Time -- which defaults to the start of the scenario analysis period -- and, depending on selections made, the appropriate date and time information.
The current animation time is saved when a scenario is saved and restored when the scenario is reopened.
Time Update Mode
The following options are available for specifying the time update mode:
Time Update Mode options
| Option | Description |
|---|---|
| Real Time | The scenario animates in real time in accordance with your computer's internal clock. Enter an Offset from the current time if desired. |
| Time Step | Enter the time interval that each animation step represents. The greater this value, the greater the distance a vehicle will move in the 2D and 3D windows each time the screen is refreshed. |
| X Real-Time | Enter a number specifying the multiple of real time at which you wish the scenario to animate. The Continue from current animation time after pause check box is selected by default. Clear the check box to have animation pick up from however much time has really elapsed since the animation was paused. |
| Time Array | Steps through the exact times in the time array when animating forward or backward. Resetting the animation sets the time period back to the first time in the time array. |
- If you select Real Time, make sure that the scenario time period and the vehicle ephemeris fall within the correct time period. Otherwise, no activity occurs in the 2D and 3D windows when the scenario is animated.
- If the Animation Step buttons are used while in Real Time or X Real Time, the time will be updated by the last Time Step entered.
- STK may not properly update date and time values to reflect daylight savings time if the scenario is not being run in real-time.
Animation Cycle
If On, select one of the following options:
Animation cycle options
| Option | Description |
|---|---|
| Stop at Time | Indicate the time at which the animation will stop. |
| Loop at Time | Indicate the time at which the animation loops back to the Start Time. |
If Off, animation continues until you pause or reset the animation.
Animation Update
Specify the amount of time between screen refresh updates.
Animation update options