In productionProbeginnerBehavior tree control flow

Recovery loops forever

Bound recovery and surface a useful failure without reducing mission resilience.

Pairs with Behavior trees and recovery in Nav2 Incident Response. Read the concept first, then diagnose it here.

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Operator report

The robot alternates spin and clear-costmap actions indefinitely.

Ubuntu 24.04, ROS 2 Jazzy, Nav2, Gazebo Harmonic, warehouse mission simulator

System boundary

Trace only the relevant path.

navigation failurerecovery subtreeretry decorator

How this lab works

You diagnose it — no command list.

Open the repair workspace and gather your own evidence in a real terminal. No diagnostic commands are handed to you — finding the fault is the exercise. Stuck? Progressive hints unlock inside the workspace.

Verification

Your repair must pass more than the visible symptom.

  • Recovery bounded to 3
  • Failure reason is reported
  • Hidden regression behavior
  • Root cause explanation