Function · Slotting Built

Put-away that earns its place.

Slotting decides where each incoming SKU should live. openWCS scores every candidate location against objectives that genuinely conflict — speed, lane affinity, resilience and balance — and the weights are configuration you own, not a vendor's hidden rule set.

How it works

One weighted score, hard constraints first.

Hard constraints filter the candidate set — lane capacity, one SKU per deep lane, a cap on how much of a SKU may sit in one aisle. What survives is scored, and the best location wins.

Velocity

Fast movers near the exit

Each location carries a distance-to-exit. Class-A SKUs are pulled toward the port for short cycles; slow movers settle deep where the longer reach rarely costs anything.

Self-taught ABC

Velocity it learns

ABC velocity class is taught in per SKU from real movement, not typed into a master record — so the layout tracks how the catalogue actually behaves.

Lane affinity

Same SKU per deep lane

A multi-deep lane should hold one SKU so units don't block each other; partial same-SKU lanes fill first to avoid honeycombing. A strong preference, tunable against balance.

Redundancy

Survive an aisle outage

A min-aisle floor and a max-share-per-aisle cap deliberately spread a SKU across aisles, so one offline shuttle/crane can't strand it — and it can be picked in parallel.

Balance

Even out the aisles

Put-away prefers emptier aisles so fill, travel and throughput stay balanced instead of one aisle becoming the hot-spot bottleneck.

Re-slotting

Correct drift off-peak

In idle windows the same scorer re-evaluates stored units and recommends moves as velocity drifts, lanes fragment or aisles skew — keeping the layout optimal over time.

Inputs & outputs

What goes in, what comes out.

Slotting is a pure decision: given a unit to store and the current state of the block, it returns the location to put it in. Everything that shapes the answer is data you own.

In · the unit

SKU + handling unit

The receipt being stored: a SKU and the handling unit it's on, with its packaging level and quantity — the thing that needs a home.

In · block state

Locations & occupancy

The candidate locations in the block, their distance-to-exit, current occupancy per lane and per aisle, and the SKU already sitting in each deep lane.

In · the rules

Weights, caps & ABC

The per-block scoring weights, hard caps (lane capacity, max share per aisle, min aisle floor) and the SKU's self-taught ABC velocity class.

Out · location

The chosen slot

A single best location — aisle, side, X/Y/Z down to the cell — for the put-away move, or a direct-to-pick forward face when cross-docking fits.

Out · move

A put-away task

The decision becomes a put-away move on the shared movement layer — the same network conveyors, ASRS and replenishment use.

Out · re-slot

Off-peak recommendations

Run against stored units in idle windows, the same scorer emits move recommendations that correct drift as velocity, lanes and aisle balance change.

Step by step

How a unit gets its slot.

Resolve the block. The SKU's storage block and its candidate locations are gathered, with current lane and aisle occupancy.
Try direct-to-pick. If a forward pick face for the SKU has headroom below its max, route inbound straight there and skip reserve.
Hard-filter candidates. Drop any location that breaks a constraint — full lane, a deep lane already holding a different SKU, or the max-share-per-aisle cap.
Score the survivors. Each remaining location is scored on velocity-to-exit, same-SKU lane affinity, aisle redundancy and fill balance, weighted per block.
Pick the best, emit the move. The highest-scoring location wins and becomes a put-away move; off-peak, the same scorer re-evaluates stored units.

At a glance

Receipt → scored location.

  receipt (SKU, HU) ─►  openWCS slotting
                         │  hard filter: lane full · max %/aisle · one SKU/deep-lane
                         │  score: velocity-to-exit · lane affinity · redundancy · balance
                         │  ABC velocity ── self-taught per SKU
                         ▼
                    chosen location ─►  put-away move
  off-peak: re-slot stored HUs toward better locations