Addressing the flexibility and specialised needs of the grocery, general merchandise, and food and beverage industries.

Capable of building mixed-case pallets from an inventory of over 10,000 SKUs, the latest evolution in order assembly systems — Automated Mixed-Case Palletizing (AMCAP) — represents a paradigm shift in high SKU-count case palletizing.

The latest generation of automated high-SKU systems currently being released provides greatly improved software and more versatile product gripping tools, capable of building a higher, more dense and more stable pallet than prior systems, with improvements in system speed, order accuracy and store-friendly flexibility. Extremely accurate, fast and reliable, the latest of these automated high-volume, mixed-case systems can access tens-of-thousands of SKUs and palletize more than 1,000 mixed cases per hour, averaging 130 different SKUs per pallet (1.2 cases of a particular SKU per pallet).

One of the most recent and technologically advanced high-SKU palletizing systems is Dematic’s Automated Mixed-Case Palletizing (AMCAP). This system serves as an excellent example of state-of-the-art advancements within this rapidly evolving technology, integrating with both high-speed, automated storage and retrieval systems (ASRS) and conventional pallet racking.

Precisely Sequenced Pallet Builds

The cycle starts with the DC’s receipt of product, for example a trailer load of 22 pallets. Each pallet is entered into the DC’s WMS which integrates with Dematic’s WCS (warehouse control system), a control system for maximising performance of order assembly systems. The WCS program has inherent functionality for running all aspects of the DC’s order assembly, including delayering, storage, buffering and sequencing, picking, sortation and palletizing functions.

The in-coming pallets are typically stored in a high-bay warehouse storage system. Once stored, the DC’s WMS releases the orders to Dematic’s WCS. The WCS sorts the data based on store requirements (i.e. aisle position) and sends the pallet information to Dematic’s PalletGenDirector software package. PalletGenDirector uses 16 different attributes of the product (length, width, height, weight, crushability, etc.) as well as the specific store requirements (i.e. aisle position) to determine the build sequence for each pallet.

These pallet builds can be assigned over multiple AMCAP units, and can be pre-planned for a short lead-time before the build takes place. The pallets to be built can also be visualized in 3D before each build cycle.

Entire pallets are then automatically or manually delayered and conveyed to Dematic’s high-speed MiniLoad and MultiShuttle buffering and sequencing systems where they are stored until needed at the palletizing cells.

Optimised Efficiency in the Work Cell

Each AMCAP cell (built on a mezzanine) is fed by two conveyors providing the sequenced cases, which are then aligned and oriented, and presented to two six-axis, servo-driven articulated arm robots for pick up. The two robots build each pallet cooperatively at a rate of greater than 1,000 mixed-SKU cases per hour.

One of the unique aspects of AMCAP is the multi-axis, end-of-arm-tool (EOAT) attached at the end of the robots’ articulated arms. This universal tool can handle all standard types of packaging including boxes of various sizes, cardboard trays, open or closed cartons, bags and large unstable containers without stopping or changing tools. There is no use of pneumatic suction technology, enabling it to grip any type of packaging. The main emphasis of the gripper is on a fast, reliable grab, which will not damage packed items.

The products are conveyed into a stop location. The robot then approaches the product and precisely picks it up. The package is held in a stable, known position on the tool, so it can be moved rapidly to the proper position on the pallet. The combined dual-robotic cycle of feeding, grabbing and placing the cartons establishes the system’s high throughputs.

Once stacking is complete, the pallet is lowered through the mezzanine floor with a lift, and as it is being lowered it is stretch wrapped for stability. The completely lowered pallet, now fully stretch wrapped, has a label applied to it as it comes out on the outbound conveyor. The system then directs the completed order pallet to an output spur for the assigned active trailer to be loaded.

Palletizing, however, continues even while the built pallet is being removed from the active build area, only a few seconds are lost in the transition. After the pallet continues down through the mezzanine, slider plates close to form a solid surface. The robots immediately begin stacking cases for the next layer on the next pallet that is being built on these slider plates. A new pallet is then raised by a lift up to the mezzanine level, the slider plates open and the cases are dropped onto the new pallet, and the robots continue. The transition from the slider plates to the pallet is done without slowing the robot’s performance. This streamlined performance has been facilitated by the coordination between AMCAP’s discrete functions – robots, conveyors, lift and slider plates.

Cube- and Volume-Optimised Dispatch Units

The computer-aided determination of the palletizing sequence also increases the pallet density. It builds cube- and volume-optimised pallets with a 90 percent-plus density, compared to the typical 70 to 80 percent density of manually-produced pallets. The software calculates the packaging contact surfaces and determines the layering of the individual packages, these are critical to producing a stable palletizing pattern.

Within the AMCAP system, stacking criteria is modified by a number of factors including case size and shape, crushability, stability factors, volume of cases per layer, number of layers, the layer pattern, and family group rules unique to stores, departments, aisles and aisle sections.

What starts out as 22 pallets when received into the DC, ends up being 20 pallets when exiting the AMCAP cells, partially because of the increased density, but also because the pallets are built to a seven-foot height which they are able to easily sustain because if the pallet’s increased stability. This greater cube utilisation reduces transportation volumes, improving cost efficiencies.