How to attach a compass to an object in STK


To determine which way an object is pointing, at any given time, you need to run a report on the object in you scenario. To simplify this, I have created a compass that you can attach to an object which will function as a real time indicator of that object's direction.

Compass in STK

Here's how you do this:

Make a copy of the desired ground vehicle, ship or aircraft.

2. If your STK object uses the Aviator propagator, follow the steps below. Otherwise skip to step 3.
  • Export an ephemeris file from your aircraft.  
  • Change the propagator in the copy to STKExternal, and load the .e file you just created.
3. Rename your newly copied object to Compass.

4. In the Model tab, load the Compass.mdl model attached to this article.

5. Scale it so that it fits around your aircraft.

6. The compass needs to be tangent to the Earth and inertially fixed.
  • In the Attitude tab select Aligned and Constrained. Change the Constrained Reference Vector. 
Compass Attitude
  • To test the result, add a North vector to your original aircraft object. It should be pointing to the red N on your compass.

7. Add a Velocity vector.

  • As you animate your scenario, the north vector will continue to point to the N as the attitude and direction of your aircraft changes. The velocity vector is the needle of your compass.
Resource File 1
Resource File 2