Knowledge-Based Real-Time Diagnosis and Repair for a Complete Robotised Handling and Storage System

DIREK - 5114

Keywords process control, knowledge-based systems, PLCs, real-time systems

Start Date: 01-JAN-91 / Duration: 24 months

[ contact / participants ]

Objectives and Approach

The objective of this project is to design and implement a new generation of knowledge-based diagnostic tools that continuously acquire data from programmable logic controller (PLC) systems, identify possible malfunctions, search for their causes and suggest corrective actions. The main innovation will lie in the use of diagnostic models that integrate the classical heuristic and associative approaches.

The project is investigating the use of deep models that reproduce the functional and operational logic embedded in the ladder logic of a PLC. A study has shown that these models contain design and engineering knowledge in a more usable form compared to that held in the minds of the designers themselves.

Two software tools will be developed at a prototype stage:

• the specifications and a demonstrator of an automatic modelling module, which will be a component of a possible PLC programming support environment (with specification and code-generation support facilities) and be able to send the models produced to the diagnostic system
• a development environment for multi-model diagnostic systems, implementing general structures, which will be an extension of an existing diagnostic system.

The tools will be tested on a synthetic fibre spinning plant.

Progress and Results

The following results have been achieved:

• a knowledge-based multi-model diagnostic tool (MMDT) has been installed and is running in the plant; its main innovation is the extensive use of deep models of the plant, together with the hollow models generally used by previous diagnostic tools
• the specification of a prototype knowledge acquisition tool (AMM, Automatic Modelling Module) to automatically extract the behavioural model of the plant from the step 5 code running the plant PLCs
• the development of the tool-kits Toros and C Max, provided by Siemens, which allowed the implementation of the knowledge-base and the inference mechanism.

The final results of the project will be:

• the refinement of the MMDT prototype
• the implementation of the AMM
• the refinement of Toros and C Max.

These results will be exploited by Pirelli, SNIA, BMT and Siemens.

CONTACT POINT

Mr Marco Rosazza
SNIA BPD - FIAT GROUP
Via Friuli 55
I - 20031 CESANO MADERNO
tel: + 39/ 362 5141
fax: + 39/ 362 514600
telex: 320503 SNIAFI I

Participants

SNIA BPD - FIAT GROUP - I - C
BMT FLUID MECHANICS LTD - UK - P
SIEMENS AG - D - P
PIRELLI INFORMATICA SPA - I - P

DIREK - 5114, December 1993

please address enquiries to the ESPRIT Information Desk

html version of synopsis by Nick Cook