Impose Constraints on Access

STK makes available a wide variety of constraints, including custom plug-in constraints, to help you model the performance characteristics and limitations of objects in the scenario more accurately. Here are two examples.

An Elevation Angle Constraint

Suppose that the sensor at Wallops functions best when the satellite is relatively low in the sky. You can model this limitation by imposing a Maximum Elevation Angle constraint on the sensor:

  1. Double-click NorthSensor in the Object Browser to open its Properties Browser.
  2. Select Basic from the Constraints area.
  3. Select the Max option for the Elevation Angle constraint.
  4. Enter 75 deg in the textbox.
  5. Click OK and observe the effect on Access graphics in the 2D Graphics window.
  6. Return to the Access report that you previously created.
  7. Click HTML Refresh Button Refresh in the Report's toolbar. Observe the change in the access times in the MEO-To-NorthSensor section of the report.

Tip: If you closed the report, simply re-create it. Select the satellite in the Object Browser, open the Access tool, and select Access... in the Reports section.

A Temporal Constraint

Suppose the employees of the Perth station that are interested in access to MEO only work from 9 am to 5 pm local time. To reflect this limitation, impose a Temporal constraint on the sensor:

  1. Select Temporal from the Constraints area in the Properties Browser for SouthSensor.
  2. Select the Local option.
  3. Enter 09:00:00 as the Start time and 17:00:00 as the End time.
  4. Click OK.
  5. Observe the impact of the constraint on Access graphics and on the report.
  6. Close the Access report.

The Access report that you just generated is only one of thousands of reports and graphs that can be created in the STK suite. We will conclude this tour by generating some reports and graphs.