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FH6 recovery mechanics (and how recovery.py models them)

Researched 2026-06-09 (Forza wiki/forums/shacknews/gamerant/player guides + the user's first-hand FH6 play). The three in-game recovery mechanics are distinct and not interchangeable — conflating them was the bug in the previous recovery code.

The three mechanics

Mechanic Controller input What it does Right tool for
Rewind Y (tap) Rolls back a few seconds of your own path, upright. Needs damage = None/Cosmetic (greyed out under Simulation). Fresh on-road impact / just-happened flip (short window)
ANNA AutoDrive D-pad Down → Down-Left → A One feature, two state branches (see below). Needs a waypoint pinned. PRIMARY "get back to the route"
Reset Car Position Pause(Start) → L3 → A Respawns upright on nearest flat road, speed 0. LAST-RESORT fallback only

AutoDrive is itself both the teleport and the drive-back

This is the key correction. Opening AutoDrive branches on the car's state:

  • Far off-road → a "transfer car?" prompt appears → A teleports the car to the centre of the road, then it drives.
  • On a road but stuck → no prompt; AutoDrive just drives along the route line.

So there is no need for a separate pause-menu teleport "escalation" for the far case — AutoDrive's own prompt is the teleport. (The earlier code wrongly treated Reset Car Position as the universal teleport that leads the ladder once AutoDrive "fails".)

Telling the two AutoDrive branches apart from telemetry

Telemetry can't read the prompt text, so _wait_autodrive_resolved uses world-position displacement (not instantaneous speed) as a small state machine:

  • Frozen (no net displacement) for a moment after opening, then a > autodrive_teleport_jump_m (30 m) position JUMP = the transfer prompt was accepted (teleport branch).
  • Net forward displacement accumulating, no jump = AutoDrive is driving (on-road branch).
  • We press A only while the car is frozen, after a short settle (autodrive_prompt_settle_s), within a bounded window (autodrive_prompt_window_s), capped at autodrive_prompt_attempts (2), and stop for good the instant it teleports OR starts driving. The old code tapped A whenever speed < 2, which spammed A into a live AutoDrive drive through every slow corner — and a stray A cancels AutoDrive.

When the episode ends (CrashDetector) — and why it matters for recovery

The episode ends (and recovery runs) on: impact, stuck, flipped, offroad, offroute, noprogress. Two route-aware terminations were added (they need centerline.npy):

  • offroad now fires at any speed (the old speed < 10 gate let a car drive fast off-road forever without resetting).
  • offroute: lateral distance from the route centreline > offroute_dist (18 m). Ending the episode the moment the car leaves the route keeps it near the route, so AutoDrive recovers it with a short drive — instead of letting it wander far, where AutoDrive's teleport drops it on a distant road with a long drive back to the waypoint.
  • noprogress: on-route but centreline arc-length not advancing for noprogress_seconds (5 s) = circling / wrong-way / stuck-at-speed.

The recovery ladder (recover())

Every reason uses the same ladder: [autodrive, reset_position, reset_to_road].

  • Rewind is removed (unreliable on this build; AutoDrive only).
  • AutoDrive is primary — it covers far-teleport and on-road-drive, and its transfer branch even rights a flipped car. Reset Car Position is the last-resort rung, reached each round only if AutoDrive can't route the car.
  • autodrive_persistent (unattended): never returns FAILED; re-runs the ladder (ending in the pause reset) with capped backoff + a heartbeat log — never a silent hang.

After AutoDrive succeeds

Cancel the lingering AutoDrive with a brake tap (autodrive_break_s ≈ 1 s), not throttle: AutoDrive drops the car at road centre with no guaranteed heading, so a throttle pulse would launch it (possibly into oncoming/a barrier).

Preconditions / open items

  • A waypoint must be pinned to the route or AutoDrive has nothing to drive toward and just stalls (→ the ladder then falls to the pause reset). Keep a route waypoint set during training.
  • The far-off-road transfer-prompt branch is the user's first-hand observation (FH6 is new and no public source documents it verbatim). The A-tap logic is deliberately conservative so that if the prompt is absent on a build, the worst case is 1–2 harmless early A presses, not the old A-spam-into-a-drive.
  • Bindings are for a controller; PC keyboard uses C for the second ANNA input.