Realtime system control by means of path expressions

A high-level, algebraic programming method for the online control of actions in a real-time, parallel processing environment is described. The method is based on the interaction of path expressions. On the basis of a set of path expressions, evocation of actions can be controlled in real-time in a fully automated way. It is shown how intelligent system behavior can be obtained by a combination of rules given as path expressions. Each of these rules specifies some partial behavior to which the system must comply. The control system operates as a rule-based action planning system that works online in an asynchronous environment. The development of the prototype system PBOS (Path Based Operating System) has demonstrated that path expression specification naturally integrates with a real-time, multitasking control syste

Interactive control of physiological experiments

Physiological and biological experiments often require the imposition of repeated influences on an organ or organic system. Then the experimental protocol requires many repetitive functions with adjustable interval times and magnitudes, which are prepared or dictated by experimental results. To control such an experimental set-up interactively with a small computer we chose a more or less general approach. A special language syntax has been developed for: (i) experiment definition; (ii) experiment composition in advance; (iii) real-time control during the actual experiment; and (iv) registration of the actual protocol parameters. The interactive control was realized using the special language and an interpreter as one of the parallel processes for the experimental control

Multi-tasking control system for real-time processing of biomedical signals

A general multi-tasking control system has been developed for real-time signal processing. This control system, written in the language PASCAL, enables tasks (expressed as PASCAL procedures) to be performed as separate, concurrent processes, with adjustable priority levels. Modifications of this system such as the addition of new processes and a change of the number of priority levels can be realised easily. The system has been used for the implementation of the real-time algorithms involved in monitoring exercise electrocardiograms. For this application an LSI 11/23 is used with the support of a slave processor for the calculation of inner products. The control system is also suitable for other real-time applications when process requirements are not too heavy