Pallet Patterns and Case Sizing: How to Size a Cobot Palletizer for Your Line

Every palletizer conversation eventually comes down to five numbers — and none of them is the robot's model name. Your case dimensions, your heaviest case, your sustained rate, your cases per pallet and your pallet size decide whether a cobot fits, which gripper it needs, and how its cell is laid out. Here is how those numbers work together, and how to measure yours before you talk to anyone.

Sizing starts with the case, not the robot

A palletizer does not handle "boxes." It handles your master case: one specific length × width × height, at one specific weight, arriving at one specific rate. Change any of those and the grip, the pattern and the cycle time all change with it. That is why a serious sizing conversation never starts with price or speed claims. It starts with a tape measure, a scale, and a stopwatch on your own line.

The five numbers you need

Measure the case you actually ship, not the nominal size on a spec sheet. Cardboard swells, tape and labels change the footprint slightly, and a case that is heavier on one side grips differently than a balanced one. If you run more than one case size, list each one separately — a cell can be taught a recipe per case, but only for cases it was sized for.

How case size becomes a pallet pattern

The pallet pattern is simply the arrangement of cases in one layer, repeated and often interlocked layer to layer for stability. Your case footprint against your pallet footprint decides how many cases fit per layer, and the pattern decides whether the stack is stable, square and within the pallet edge — overhang weakens cardboard and invites damage, while large gaps waste the layer.

Stack height matters too. Layers per pallet set the total height the robot must place to, and a tall, heavy stack changes both the motion and the stability check. When we set up a rental cell on site, we create the recipes for your pallet patterns during installation and start-up — but those recipes are only as good as the case measurements behind them.

Weight: the 20 kg ceiling and what it really means

Our cobot palletizer cells handle cases up to 20 kg (44 lb) each. That is a per-case limit, and it is the heaviest case you run that counts — not the average. A line whose typical case is 12 kg but which occasionally runs a 24 kg case is not a cobot fit for that heavy case, full stop.

Weight also interacts with speed. Heavier cases are moved more deliberately than light ones, which is one reason sustained rate — covered in How Many Cases Per Minute Can a Cobot Palletizer Handle? — must be checked against your heaviest case, not your lightest. And as our safety guide explains, a heavy case is also a safety input: grip security and cell layout are set for the worst case you run, in Are Cobot Palletizers Safe?

Reach, footprint and utilities

Our cobot has a reach of up to 1,880 mm. In practice, a single fixed cobot picks from the conveyor and places to pallet positions on its left and right. It cannot directly serve four pallet positions — that takes a linear rail or a second robot, which is a different cell and a different layout.

For footprint, a typical cell per our OEM layout drawing is about 3,000 × 3,000 mm of fenced area, with two pallet stations of 1,100 × 1,100 mm and the conveyor infeed at the top centre, with a safety light curtain on the open side. Safety guides and a cage are options fitted when your risk assessment or plant rules call for them. Utilities are simple: each robot cell needs 110 V power, maximum 15 A, plus a compressed-air connection. Delivery to your site typically takes 3–4 weeks, and installation includes on-site start-up, training and creating your pallet-pattern recipes.

Running more than one case size

Many plants run two or three master cases: for example a 12-pack and a 24-pack of the same product, with different footprints, different weights and different cases per pallet. That is normal, and a cobot cell handles it with a stored recipe per configuration — pick pattern, layer pattern and placement for each. What matters at sizing time is honesty about the full list: every case size, its weight, its share of your volume, and whether two sizes ever need to run to two pallets at the same time. That last answer can be the difference between one robot and a rail or second robot.

Common sizing mistakes

• Sizing to the average case. Grip, speed and safety are all set by the heaviest case. Size to the worst case you actually run.
• Sizing to peak rate. A burst of 12 cases per minute for ten minutes is not the same as a sustained rate all shift. Give the sustained number, and mention the peak separately.
• Guessing case dimensions. Nominal sizes from a catalogue miss tape, swell and real-world variation. Measure a filled, sealed case.
• Forgetting the pallet. Pallet size, condition and how full pallets leave the cell (forklift route, pallet jack) are part of the layout, not an afterthought.
• Ignoring floor space at the line end. Measure the actual area available — length, width and the conveyor position — before assuming a standard cell fits.

The bottom line

Sizing a cobot palletizer is not complicated, but it is specific: case L × W × H, heaviest weight up to 20 kg (44 lb), sustained cases per minute, cases per pallet, and pallet size. With those five numbers, the pattern, gripper, reach and footprint questions answer themselves — and so does the honest question of whether a cobot fits your line at all. A cobot palletizer rental lets you prove that fit on your real line, with your real cases, before any purchase decision — the same low-commitment logic we break down in Palletizer Rent vs Buy and How Much Does a Robotic Palletizer Cost?