TL;DR
Shuttle carrier positioning errors usually come from a dirty or damaged rail barcode tape, a worn encoder, or debris on the rail. Clean the locating tape and inspect the encoder read head before recalibrating.
What you might see
- positioning fault alarm for one or more shuttle carriers
- carrier reporting wrong bay address
- tote not retrieved or stored correctly at target location
- carrier stopping short of or past the target column
Likely causes
Contaminated or physically damaged barcode position tape on the shuttle rail causing read errors
Worn encoder or encoder read head losing signal, causing the carrier to lose position reference
Rail debris (cardboard, shrink wrap, dust) blocking the optical position reader
WCS (warehouse control system) bay mapping out of sync with physical shuttle position after a power loss
Required tools
- WCS fault log access
- Lint-free cloth for optical component cleaning
- Replacement barcode position tape (system-specific)
Safety first
- AS/RS shuttle aisles are extremely hazardous while carriers are in motion. Entering the aisle requires a safety interlock to hold all carriers. Verify carrier hold status before entry.
- High-racking systems involve fall hazards. Use approved elevated-work platforms and fall protection when inspecting upper-level rail sections.
Procedure
- 1
Pull the fault log from the WCS for the affected shuttle. Note the last known position and the reported fault position to narrow the search zone on the rail.[1]
- 2
Command the shuttle to a safe parking position using the WCS or the local operator panel. Do not attempt manual entry while the shuttle is active.
Warning: AS/RS shuttle aisles are machine-only zones when shuttles are running. Before entering an aisle for inspection, use the aisle entry interlock or safety gate to command all carriers to a hold state and confirm no carrier is in motion. - 3
Inspect the barcode position tape in the fault zone for contamination, peeling, or physical damage. Wipe with a lint-free cloth if dirty.
- 4
Inspect the carrier's optical read head for dust, debris, or damage. Clean the lens with a dry lint-free cloth.
- 5
Power-cycle the affected shuttle from the WCS carrier management screen and re-home it to the reference position.
- 6
Run a test cycle to the fault zone location and confirm the carrier positions correctly. If the error recurs, order a replacement position tape section or read head.
Sources
Dematic (KION) Dematic Multishuttle AS/RS (Automated Storage) general technical documentation, Dematic (KION)
AS/RS shuttle carrier positioning systems, optical encoder and barcode tape maintenance, general material handling references (general)
More guides for Dematic (KION) Dematic Multishuttle
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Stop fixing the same fault twice.
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