Nordic Offshore Systems commissioned a real time expert system to monitor the drilling process on offshore oil-drilling platforms during the pre-production exploration phase.

The system, designed and implemented with consultants of InterFace Computer GmbH in Germany, is a safety device to recognize non-optimal drilling and warn of imminent danger.

Offshore oil-drilling for research purposes is a very risky process, because the drilling action itself in only partially known geological conditions can cause e.g. natural gas explosions due to heat, pressure, and vibration.

Accidents carry the potential to incur major damage to personell, equipment and the environment, and severe economic penalties due to lost operational time. Therefore, preventing accidents expert knowledge is very cost effective.

The system consists of three parts:
(1) Condition analysis: 120 sensor values are accumulated, evaluated and interpreted in real time,
(2) Simulation: mathematical and physical models simulate the drilling process and uncover discrepancies between measured and calculated values, and
(3) Diagnosis: the discrepancies are evaluated, investigated for possible causes and explained.

The knowledge base is written in IF/Prolog for easy maintenance and expressive power, local mixed inference is used to obtain the evaluation results.

This system is still now on operation in 4 sites including a nordic offshore oil field.

Hardware: Apollo DN 570, IBM-PC, Integrated Solutions
Software: IF/Prolog, UNIX, C, Fortran, db++