Unscheduled teleportation occurs when Third Person Characters with AI are walking.

When multiple Third Person Characters enter a narrow staircase with handrails on both sides, some of the stuck characters may teleport to the air.

I am not clear on the conditions under which this occurs, but do you have any idea what might be causing it? I would like to have a clue how to solve this problem.

  • Unreal Engine 4.27.2
  • 50 to 100 characters (use Character Class), and they are controlled by Detour Crowd Manager.
  • I tried RVOAvoidance too, but the same thing happens as in Detour Crowd Manager.
  • There are NavMesh on the stairs as well as on the floors leading to the start and end of the stairs.
  • Events often seem to occur in the gap between NavMesh and structure.
  • Teleport to the air or to the floor above.
  • Events occur infrequently. The event occurs within a few Characters when the stairs are descended two or three times.

floor with Navmesh -------------------
.
.
.
floor with Navmesh -------------------
/
stair with Navmesh /
/
floor with Navmesh -------------------
.
.
.
floor with Navmesh -------------------