Today's machine centres are being increasingly automated but often operate as a collection of isolated machines run by a variety of computer systems. Clearly, such heterogeneous computing and control environments present a formidable barrier to the problem of interoperability. Already there are vendors that provide a partial solution to the problem, since they provide methods of interoperability only between machines that they supply. Vendor-specific methodologies are in general proprietary, and do not inter-operate with any other vendor's equipment. What's needed to facilitate widespread machine-to-machine data exchange is a universal methodology to connect to optimizer data, or any data for that matter, with plug-and-play simplicity. In order to enable enhanced data availability and also to lay the foundations for the evolution of process monitoring and control in the sawmilling industry, this project was undertaken to create a common methodology for vendor-neutral data exchange between machine centres, process monitoring and control systems, and business systems.
A task forceª, with members drawn from sawmilling and equipment vendor companies, selected the well-established specifications for data exchange published by the OPC Foundation, a consortium of companies committed to universal data exchange in industry. While these specifications specify standards-based methods for data exchange, the task force recognized that there was an additional layer required to create standard plug-and-play access to sawmill optimizers. This additional standardization layer specifies exactly what data is made available per optimizer type. After testing these ideas for primary breakdown optimizers and PLCs in a sawmill-based pilot project, the task force unanimously adopted the OPC specification and our per-optimizer layer as a practical standard for data exchange in the sawmilling industry.
Given this initial success, however, there needs to be a continuing effort to ensure that the evolving sawmill standards eventually are applied to all optimizer types, and that sawmill managers and executives are aware of their benefits. Continuing effort must ensure that multi-vendor support per optimizer type does not result in tag list fragmentation which would undermine the benefits of standards. The methodologies adopted during this project will never become standard in the sawmilling industry unless the majority of sawmillers demand the standard OPC optimizer interfaces defined by this project.
ª In this document, “task force” is used interchangeably with “working group”. On 21 March 2002, a standards committee was struck from task force members, but soon lost its meaning when the task force adopted an email list approach to collaboration. The email list was much more inclusive and therefore much larger, and became the defacto “working group”. By project end, the working group consisted of 40 members.