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Industrial Automation



Arnott's Biscuits Huntingwood N.S.W.

This installation features seven stacker cranes, five servicing the high rise store and two servicing the pick areas, and an extensive skid board conveyor system.

It also features a pick-to-light system, carton conveyors, and a sortation system, which is controlled by two PLCs, one of which is interfaced to the “Movement Controller”for the purpose of receiving orders and reporting results.

The heavy-unit-load conveyor system is a complex two-level conveyor system, which incorporates single conveyors accumulating several pallets, limited in number by the size of the motors rather than by the length of the conveyors. This arrangement presented a formidable challenge for the automatic construction of the mimic diagram. As a result, we are now confident that the “Movement Controller”can automatically construct a mimic diagram to handle any two-level, orthogonal, heavy-unit-load conveyor system, and should there arise a need, could be extended beyond the two levels.

The conveyor system incorporates drop-rollers at the crane infeeds and outfeeds, alignment bars, sizing stations, stretch wrappers, elevators, scissor lifts, light curtains, and skid-board to pallet converters.

The conveyor system services several forklift infeeds and four robot palletisers transferring loads of biscuits to the infeeds of the five high rise cranes.

These five stacker cranes then either locate these loads into the high rise or raise them to their outfeeds on the upper level conveyors.

Loads reaching the outfeeds of the five stacker cranes (either retrieved from the high rise or lifted from the infeeds) are conveyed to either of the two pickface cranes, the order picker or to one of three lowerators, by way of which they are returned to the lower level conveyor system for delivery to the forklift outfeeds via skid-board to pallet converters.

We have upgraded the cranes on this site to our latest Crane PLC software release. This software is described in Stacker Cranes.

Communications between the “Movement Controller”and the cranes is via an infra-red serial link.

Communications between the “Movement Controller”and the host computer system was, originally, via a serial link using a protocol designed specifically to suit the application.

Cummerbund Middleware

The host computer has now been replaced using software based on SAP, to which we communicate by the exchange of files with XML content. The files are first exchanged between our computer and another, on the other side of a firewall, using FTP protocol, with FTP servers and clients in both the “Movement Controller” and in our own middleware software running on that other computer. This middleware software we have called "Cummerbund Middleware". Cummerbund Middleware uses FTP to transfer the files to and from the “Movement Controller”and local directories. These local directories are then made available to Microsoft's BizTalk for transfer to the host computer, located in Melbourne.

I was commissioned to produce this middleware by Arnott's after they trialled three proprietary middleware products and found that not one of them could reliably deliver the files in the correct order.

Other Details

All PLCs are Allen-Bradley.