Aspects of diagnostic schemes for biomedical and engineering systems

摘要

The paper considers aspects of work carried out on projects in medical diagnostics and engineering fault detection and control, and shows the development of some ideas in signal processing and diagnostic techniques; in particular regarding models, estimators and decision schemes. The fact that analysis of human biological systems is restricted by powerful ethical and legal constraints would seem to lead to fundamental differences of approach to medical and engineering problems. In the research considered this did not seem to be a dominant issue. The use of system simulators as reference standards, and blackboard schemes for knowledge integration, has shown to advantage in both fields. Methods for increasing the usefulness of limited data have been successfully applied to decreasing the cost associated with sensors for a given standard of diagnostic reliability. The science of engineering control and diagnostics has benefited from the use of observers based on state-space descriptions of the system. An observer provides an altemative reference model which has been used to generate residuals when faults occur. A new technique employing sliding-mode observers to recreate fault signals is introduced. This idea is extended for use in a medical context.