HERACLES provides an integrated set of tools covering the following areas: intelligent CAD, PLC programming using state-of-the-art editing techniques, incorporation of existing hand-written PLC code, simulation of the design, monitoring of both the simulation and the completed plant, and diagnostic support for the completed plant. The fundamental concept is the "object", which is a component of the plant which has both hardware and software aspects. The user can build up a component library of re-usable templates for these objects, so that when a new object is generated from a template and is placed on the CAD drawings, the associated PLC code is also generated, keeping the hardware and software designs synchronised. All information (other than CAD information) about the objects is stored in a project database. Information can be extracted from this database to supply the simulator (a third party product), the monitoring system, and the diagnostic system. The user never has to provide a piece of information more than once, measuring the consistency of the whole system. Mechanisms are provided to encourage the re-use and modification of templates, both within a single plant design and passing on from one design project to the next.
A prototype system for computer aided engineering design has been implemented on the Sun Unix platform, using Motif as a user interface standard. Some development is taking place on SCO Unix, and Windows NT is being evaluated as a possible future platform. A third party computer aided design (CAD) modeller and electrical CAD tool have been augmented by an intelligent CAD module, which allows the specification and enforcement of design rules for the mechanical design. It has a neutral interface to the CAD modeller, giving the possibility of different CAD modellers.
The programmable logic control (PLC) code templates are generated with a graphics user interface (GUI) based editor based on the 'state chart' method. This allows a higher level view of the design and the software interaction of different objects than is possible using traditional editors. It is fully capable of the detailed control of PLCs provided by traditional methods. Output is IEC1131-3 compliant PLC code. Both of these modules deposit data in the component library and project database by interfacing with the library manager server process, which provides the application neutral interface to the data. A simple user interface (the library maintenance tool) is provided for the library manager, but it is expected that the user will usually interact with the CAD tool and the PLC tool. A third party simulation tool has been interfaced to the system. All dependence on this particular simulator has been confined to a small program (a compiler) which can be replaced if another simulator should be required. The COROS monitoring system has been interfaced by similar means.
The multimodel diagnostic system from the previous EP5114 DIREK project has been used and updated to draw most of its information from the project database, forming a model of the plant which can reason from symptom to cause. This system is greatly superior to an expert system, in that it minimizes the use of the time of design engineers and can produce correct diagnoses for faults which have not been seen before. It is useful in the set up and debugging phase of a plant and can be used by maintenance engineers, but it is particularly intended to be usable by shopfloor workers.
HERACLES has been designed as an open system, with all information passing through the project database. The neutral interface to this database is intended to make it simple to replace any part of the system, so that customers with a preference for other software (eg a different monitoring system or a different CAD modeler) can be accommodated. The consortium intends to encourage third-party software suppliers to integrate their software with the HERACLES system.
TW11 8LZ Teddington