test_unitFacetDrag

test_unitFacetDrag.facetDragComp(dens, areas, coeffs, normals, vel, att)

Reference facet drag force in body frame using inertial velocity.

test_unitFacetDrag.test_facetDragAtmosphereRelativeVelocityWhenWindLinked()

Test that drag uses atmosphere-relative velocity when wind message is linked.

Two simulation steps are needed: step 1 populates windInData via ReadInputs(); step 2’s computeForceTorque uses that cached wind velocity. The force at step 2 is compared against facetDragComp using step-1 cached density/wind and step-2 velocity/attitude.

test_unitFacetDrag.test_facetDragInertialVelocity()

Verify drag uses inertial velocity when no wind message is linked.

Velocity has a component along the default facet normal [1, 0, 0] to ensure non-zero projected area and a non-trivial reference force.