Emergency Recovery for Heavy-Duty AMR: Safe Towing, Manual Release, Isolation, and Route Clearance

AMR failure is not a question of “if” but “when.” For heavy-duty AMRs (1,500 kg+ payload), post-failure recovery is far more complex than light-duty — you cannot push a loaded machine the way you would a lighter one.

If the recovery plan is improvised after a failure occurs, consequences may include:

• Extended line downtime — no one knows how to safely remove it.
• Payload damage — incorrect removal causes load to fall.
• Personnel injury — improper towing or release causes accidents.
• Equipment damage — forcibly moving a loaded robot damages the drive or brake system.

Recovery planning is a procurement-stage design input, not a post-failure emergency response.

Plan Recovery Before the First Failure: What to Confirm During Procurement

The goal at procurement stage is not to write a step-by-step recovery manual — it is to confirm that the equipment, tools, procedures, and responsibilities are defined before deployment.

What to confirm with the supplier:

• Fault classification guide — what fault types are possible, and what is the recommended recovery strategy for each?
• Energy isolation procedure — how to safely disconnect battery and drive energy?
• Brake release method — mechanical lever, electromagnetic, or pneumatic? What tools are needed? Where is the release point?
• Towing point location and rated towing force — is there a designated towing point, not just any hook?
• Lift mechanism manual release — if the lift fails with payload elevated, how is the payload lowered or supported?
• Required recovery equipment list — what tools, jacks, supports, or towing equipment does the site need to have on hand?

These should be formal documents, not verbal suggestions.

Fault Classification: Match Recovery Strategy to Fault Type

Different fault types need different recovery strategies. The procurement plan should cover at minimum:

Confirm fault type before moving — do not tow blindly. Towing during a brake failure may cause uncontrolled rolling; towing during a lift failure may cause the payload to fall.

Energy Isolation and Payload Stabilization

What to request from the OEM:

• Energy isolation procedure — how to safely disconnect battery and drive energy for this model.
• Payload stabilization guidance — what support methods are approved for elevated payloads, high-CG loads, and ramp conditions.
• Safety function state during recovery — what safety functions remain active or are disabled during approved recovery procedures.

Confirm the supplier provides a fault classification guide and energy isolation procedure as formal documents.

Brake Release, Steering State, and Towing Points

Brake release method to confirm: After a fault, brakes typically lock and the robot cannot move. Confirm the approved brake release method for this model.

Steering state: Confirm whether wheels lock in direction after brake release and what manual adjustment is needed.

Towing points: Confirm the designated towing point location, rated towing force, and required towing equipment. Confirm the site has matching equipment — if not, it needs to be procured in advance.

Recovery in Narrow Routes and Intersections

Narrow route recovery challenges:

• Towing equipment may not fit in narrow aisles.
• Robot + payload turning in narrow aisles is difficult.
• Intersection recovery space is limited.

Strategies to plan for:

• If the robot can still self-drive (software fault) → manual mode low-speed out of the narrow section.
• If cannot self-drive → use manual towing tools.
• If payload can be unloaded → unload to reduce weight, then tow.
• If route is blocked → clear obstacle or tow from the other end.

Assess all narrow sections and intersections on the route — what is the recovery plan if a fault occurs at these locations?

Lift-State Faults: The Most Dangerous Recovery Scenario

Lift-state faults are the most dangerous recovery scenario — payload may be suspended and cannot be lowered if the lift mechanism fails.

What to request from the OEM:

• Approved lift mechanism manual release/lowering method for this model.
• Approved support equipment specifications (hydraulic jack, support frame) and load ratings.
• Prohibitions — what must not be done during a lift fault (e.g., towing with suspended payload).
• Required competent personnel for lift-state recovery.

Confirm the lift mechanism’s manual release/lowering method. If the payload cannot be lowered during a lift fault, what is the approved recovery plan? Does the site have the required support equipment?

Recovery Planning Checklist

Recovery Decision Tree

Recovery Drill Checklist

Recovery Planning Inputs

1. Design recovery plans at procurement stage — not improvising after a fault.
2. Different fault types need different recovery strategies — classify before acting.
3. Energy isolation and payload stabilization are prerequisites before moving — cannot skip.
4. Brake release method and tools must be confirmed in advance — no time to figure it out during a fault.
5. Towing points and equipment must match — heavy-duty AMRs need professional towing equipment.
6. Narrow route recovery plans need separate assessment — towing equipment may not fit.
7. Lift faults are the most dangerous recovery scenario — suspended payloads need support equipment.
8. Drill recovery operations regularly — not “knowing is enough,” actual hands-on practice is needed.
9. Specific brake release/towing methods must come from manufacturer instructions — no workarounds for safety systems.