Skip to main content

Required: Drone Collision Setup

The #1 setup mistake

If pathfinding always returns "Path Not Found", this is almost certainly why. Fixing it takes about 30 seconds.

Why this matters​

The navigation system finds nodes and validates paths using traces (sphere traces on a trace channel — Visibility by default). Every query starts at the drone's own location.

If the drone's collision blocks that trace channel, the very first trace hits the drone's own collider, reports "blocked," and the system concludes there is no visible node — so it returns no path. Every time.

The fix: make the agent transparent to the navigation trace channel. Only world geometry should block it.

The setup​

On your drone's collision component (the root sphere on BP_AIDrone):

  1. Set the trace response for the navigation channel (Visibility by default) to Ignore (or Overlap).
  2. Keep the object response to WorldStatic as Block so the drone still physically collides with walls during movement.
Trace responses and object responses are independent

Movement sweeps and physics use object responses; the nav queries use trace responses. So a drone can block WorldStatic (solid for movement) while ignoring Visibility (transparent to nav) at the same time. Configure them separately.

Notes​

  • ObstacleTraceChannel on the manager and volumes defaults to TraceTypeQuery1, which resolves to Visibility in a stock project. If you add custom trace channels, keep the manager, the volumes, and the drone's "ignore" response all pointing at the same channel.
  • Always make sure trace queries ignore the asking actor (the system already adds the owner to Actors to Ignore, but the channel response above is the part you must set).
  • Size the drone's collision sphere a touch smaller than its visible mesh (e.g. mesh ~80–85, sphere ~75) to avoid snagging on wall corners.

Once this is set, re-run Bake Navigation and your paths will resolve.