Conventional control systems are designed to be deterministic because non-determinism is considered unacceptable. Increasing I/O point density will confirm the limits of standard control architectures, and signal the demise of deterministic control. A hierarchical control system is subject to complex software constraints, communication conflicts and network-speed limitations. The upper limits appear to be constrained only by data rates. The system solution of increasing bandwidth does not work. Removing the need for data rate does.

Few contemporary control systems have achieved practical I/O point counts of more than a few hundred thousand. By contrast, programmable, intelligent, autonomous I/O systems with algorithmic (rule-based) response mechanisms have no theoretical complexity limit. Vastly improved performance will be achieved at a fraction of the cost of deterministic hierarchical systems.

Over the past several years, Complexity (Chaos) Theory analysis is demonstrating that so-called deterministic systems are, in reality, non-deterministic (brittle or prone to failure) when complexity increases. Conversely, it is being demonstrated that interacting autonomous agent systems on "the edge of chaos" provide predictable performance - locally non-deterministic, but globally stable and predictable.

Secret agent

The software architectures required to achieve "self-organizing systems" are still somewhat new, but practical applications are emerging. Change in the relative relationships among cost/size/complexity heralds the next revolution in control. The transition will occur away from traditional hierarchical and procedural controls to rule-based behavior. When each I/O clump becomes intelligent, control will be handled locally through intelligent peer-to-peer communications between the sensors and actuators.

Beyond just robustness of the system and improved overall performance, the increasing connectedness of peer-to-peer control systems brings Metcalfe's Law (exponentially increasing effectiveness) and the new science of Complexity into play. The result is an intrinsically different kind of operation - complex adaptive systems (CAS). These systems yield significant advances through reduced software complexity, faster and easier installation, robust performance and vastly improved flexibility, with the capability to handle much larger numbers of real-time sensing and control connections.

Within the next decade, today's concept of software will disappear - it will become part of the product, just as today's firmware is not external and separate. The only external software needed will be in the browser - everything else will be "applets" and similar "client-side" operations, triggered by "objects" and "agents" that reside somewhere within the system.

These types of systems have roots in the work that is being done on artificial life and genetic algorithms at places like the Santa Fe Institute. During the next decade, the results will become evident in factory automation and process controls. If you wait, you'll be too late.