Operator Commands Research Articles

Use of computer network to achieve testing flexibility

Powerplex Technologies, a joint venture between Magna International, a large North American auto parts supplier, and Brown; Boveri & Cie, of Mannheim, West Germany, has recently established sodium-sulphur battery and module test capability. The test system is based on a network of computerized battery test stations. These test stations, described in more detail below, are capable of cycling and characterizing batteries consisting of 187 V strings or battery submodules made up of 2 50 V strings. The system has been designed to minimize the need for operator training. Operator commands are entered by means of touch screen terminals. The networked stations allow the flexibility required by both development and manufacturing. Additional test stations can easily be added as required while maintaining central storage of all test results. The test information handled by this system includes amp hour capacities, cell impedance, voltage, and temperature characteristics.

An Approach of Dynamical Allocation of Supervision Tasks Between Man and Computer in Control Rooms of Automatized Production Systems

The variability of human operator's performances in the supervisory and control tasks of automatized, industrial systems may lead to serious errors endangering not only the production system but also himself, and the environment, as well.One possible method for reinserting the operator Into the control and supervisory loop of these systems is the dynamic allocation of decision tasks between man and computer.This article proposes a principle for dynamic allocation of information between the two decision makers, man and computer to the end of optimizing the decision-making team's performance under the constraint of the operator's maximum permissible workload during supervision of the process's disturbed functioning.Performances and workload are estimated on line from a decision model receiving the operator's information and commands. This model comprises two decision sets : one “strategical”, which defines which variable to survey, the other “tactical”, which selects what decision or action to take on this variable. These two sets comprise several stages : event detection, situation assessment, decision-making or action. A feasibility study defines the model's functioning, as well as the worlkoad indices it can provide on line

The design of a portable micro-based weighing instrument

This paper describes an instrument suitable for accurately weighing coins, banknotes, letters and other items of up to a few kilograms in weight. A microcomputer-based hardware configuration is described which is controlled by a collection of structured software packages. These can be readily adapted to a variety of specific applications revolving around accepting operator commands, weighing and displaying information such as the cost or value of the item being weighed. The final product involves careful hardware choices and in particular, software techniques aimed at producing a reliable and maintainable instrument of reasonable cost.

Automation in the biomedical laboratory.

Automation resources are used to ease the tasks of recording, classifying, and summarizing experimental information. Three instrumental architectures are examined. Their advantages and limitations are discussed. Multiprocessor structures are shown to combine the advantages of the others. In software, state graph notation is seen as an example of a systematic solution to laboratory automation. A laboratory applications oriented operating (LAOS) is defined. Automation resources are viewed as a vertical integration of multiprocessor hardware, associated software tools, and LAOS as a superstructure. The operating (OS) provides for synchronization and communication among processes executing on separate processors. A human interface converts simple operator commands and instructions into files composed of OS primitives which can be executed by the system. LAOS also monitors high level synchronization and experimental control of the subordinate processes. Expert system techniques are examined as a means of achieving a highly automated computer-based laboratory instrument.

An APL batch scheduler improves service and system management

An APL.MS 2 system is described which enhances the behavior of the batch task scheduler for the Univac 90 series system: VS/9. In addition to permitting customized task control on a per-shift basis the system manager can interactively tune the system's batch load. The workspace communicates through operator commands and implements a simple algorithm which spreads the batch load so that both large and small tasks can execute. This work is an instance of the application of APL to systems programming in order to provide elegant interactive operating system tools.

Fast Synchronous Beam Property Modulation Using a Large Distributed Microprocessor System

One of the design objectives of the new CPS controls system is to permit changing the setting conditions from one machine cycle to the next in order to serve different users with different beam properties. Cycles may be as short as 650 ms and for the PS Booster (PSB) about 1000 parameters may have to be refreshed each cycle. This task is handled by 20 microprocessor-based Auxiliary CAMAC Crate Controllers (ACC). This layout offers three major possibilities: (i) fast and reliable parameter refreshment in each cycle; (ii) the microprocessors constitute a distributed database, which allows autonomous execution of complicated tasks triggered by simple commands from the process computer; (iii) the microprocessors allow complete decoupling between the severe process real-time constraints and human interaction: asynchronous operator commands are executed in a precise synchronous way with the process.

A distributed process control system for a multi-stream polymer plant

A distributed control system was designed and commissioned within ICI to replace existing obsolete controls on a polyester polymer plant. The system comprised six computers, one for each of five polymer streams linked in a star network to a sixth which acted as a supervisor.The polymer stream computers performed measurement and control duties, alarm checking and plant sequencing. The supervisor machine had no control duties but sorted information received from each out-station for displays and management logs. Operator communication was via a novel control panel and colour visual display units. All operator commands were screened by the supervisor before being sent to the outstations. A smaller local control panel was linked directly into each outstation for use in the event of supervisor system failure.The supervisor system was also used for storage of batch information and down line loading of computer programs for each polymer stream. The development potential and flexibility of the system was enhanced by remote editing of plant sequences through the supervisor, as required. Recording of such charges on disc storage and the ability to recall development programs on demand.

A Distributed Process Control System for a Multi-Stream Polymer Plant

A distributed control system was designed and commissioned within ICI to replace existing obsolete controls on a polyester polymer plant. The system comprised six computers, one for each of five polymer streams linked in a star network to a sixth which acted as a supervisor.The polymer stream computers performed measurement and control duties, alarm checking and plant sequencing. The supervisor machine had no control duties but sorted information received from each out-station for displays and management logs. Operator communication was via a novel control panel and colour visual display units. All operator commands were screened by the supervisor before being sent to the outstations. A smaller local control panel was linked directly into each outstation for use in the event of supervisor system failure.The supervisor system was also used for storage of batch information and down line loading of computer programs for each polymer stream. The development potential and flexibility of the system was enhanced by remote editing of plant sequences through the supervisor, as required. Recording of such charges on disc storage and the ability to recall development programs on demand.

Microprocessor Based Load-Frequency Controller for Electric Power Networks

The control and statistical tasks as well as the hardware and software blocks of a microprocessor based load-fre quency controller are discussed. Data acquisition from twenty four digital cyclic emitters and several analog links joint with a control sampling rate of three seconds, lead to the use of two microprocessors sharing a common memory. The scheduling of the different tasks to the two processors, a rough description of the operator commands and the three page report are also presented.

Software development on the EMI head scanner

A method has been developed to run the general purpose operating system RDOS on the same disc of the head scanner computer as is used for scanner software and data. This made it possible to develop additional software in high level programming language for image processing, based on original image data on the disc. All new images produced by the program are stored on the disc in the same format as the original images. This makes it possible to handle processed images exactly as the original ones and to do multiple operations. The following processing has been included in the program so far: subtraction, smoothing, density profiles, vertical reconstructions, magnification and labelling. A set of operator commands has been developed which are very similar to the ordinary commands for the scanner, which makes the program to appear being a direct extension of the standard scanner software.

The CESR Control System

Computer control of CESR, the Cornell (8 + 8)GeV e+e- colliding-beam facility, places special emphasis on response speed, operator convenience, and economy of programming effort. Individual subsystem computers (PDP-11/34@) run autonomously under standard operating systems. Each has its own high-speed data bus network through which it controls accelerator components and accepts operator commands. Message traffic between computers is restricted to links which give a central DECsystem-1070 direct memory access to each of the PDP-11s. The 1070 can control higher-level operations by using slave tasks running in the PDP-11s; it also makes its resources available for data storage and manipulation, editing of program source files (mostly FORTRAN), and preprocessing by the FLECS translator.

Evolution of a virtual machine subsystem

The rapid spontaneous growth of the IBM Corporate Job Network is probably attributable to the design philosophy employed by its software support. The lack of dependence on uncommon computer machinery and VM/370 hypervisor modifications, the ease of installation requiring no system generation or unusual virtual machine specification, the familiarity of the operator command language and procedures for subsystem loading and maintenance, the relative operational independence afforded by the peer relationship of the interconnected systems, and the simplicity of the user interface have encouraged computer installations to invest some effort to give VNET a trial. The simulated unit-record device interface affords operating systems running under VM/370 some access to the network without any software modifications at all. Initial experiences with an unfamiliar computer system interface appear to generate strong lasting effects. A crucial factor in the success or failure of new system software is its cooperativeness with naive users.

Software organization of a microcomputer-based data-acquisition system

Abstract Designing the hardware for a modular data-acquisition system is reasonably easy. The required inputs and outputs are analysed, suitable modules are selected and then assembled together with power supplies and control panels in standard cabinets. Software design is another matter, however, as requirements can vary greatly from system to system and from time to time in the same system. Various factors affect the software requirements: the number of inputs and outputs, the types of input, signal conditioning and processing required, alarm facilities, scan pattern, log and alarm display and printout facilities, legends and texts, and operator command and message facilities. This paper describes how the required software is provided by means of variable size index-linked data arrays. The specification of a particular system and a description of the hardware are given in so far as they facilitate the description of the software organization.

TDC 2000 Digital Instrumentation System

The study starts with the new viewpoints used by Honeywell as basis for the development of the TDC 2000 Total Distributed Control System. Secondly, the system architecture is discussed, as follows:TDC 2000 Controller, a standard eight function multi input-output controller, capable of being configured on-site to users' requirements. The controller is interfaced to the Data Hiway, thus allowing remote supervisory equipment full access to local control data.Operator Station provides operator with relevant process information, accepts operator commands for a kayboard and makes necessary changes over the communication system.Interface with computers is arranged by communication through Data Hiway. Computer thereby may access and alter distributed data base of controllers to ascertain the status of each loop for data acquisition or to directly control the setpoints or outputs for supervisory and DDC operation.After that the scope of the TDC 2000 system at Kaipola Mills is introduced together with other instrumentation included as well as the operating principles of the system.As summary, a review of special actions required by the new system and an estimate of the success of the whole instrumentation.

Real-Time Computer System for the Data Acquisition Net Control

The real time operating system OPAW for the data acquisition net control is presented. It is a clock driven system based on two levels of clock interrupts. The system performs simultaneous reading from up to 100 sensors, real time processing of the input data and displaying results onto the printing devices and magnetic tapes. It is provided with convenient operator's command language and performs current supervision of the run time errors. This paper gives the presentation of the hardware and software configuration of the system with description of the main program modules.

Real-time computer system for the data acquisition net control

The real time operating system OPAW for the data acquisition net control is presented. It is a clock driven system based on two levels of clock interrupts. The system performs simultaneous reading from up to 100 sensors, real time processing of the input data and displaying results onto the printing devices and magnetic tapes. It is provided with convenient operator's command language and performs current supervision of the run time errors. This paper gives the presentation of the hardware and software configuration of the system with description of the main program modules.

What to Expect in Solid-State Industrial Drive Systems

Solid-state control has rapidly replaced conventional electromechanical devices and vacuum tube electronics in its first decade of industrial usage. The growth of solid-state applications has been evolutionary and based on a practical approach to utilizing the optimum available solution, both economically and technologically, to achieve improved control system reliability and performance. The application of solid-state electronic devices is discussed from the input of the operator's commands through a typical industrial control system to the power conversion equipment that supplies the drive motor. Frequency of failures in solid-state devices is so low that maintenance men do not retain familiarity with circuits and device theory. This has necessitated the need for low-level maintainability through the use of functional plug-in printed circuit cards, full-time instrumentation, light-emitting diode logic status indicators, and system engineered diagnostic test circuits built into the system. The future looks promising for further technological developments in solid-state devices. A continued growth in solid-state industrial drive systems is assured with expected trends toward further development of adjustable frequency power conversion systems, and hybrid logic/control systems.

Paper 23: Automation of Control Systems for Reciprocating Compressors

Progress made in reciprocating compressor control systems in recent years has been dramatic. Extensive use of sophisticated compressor control systems has taken place in the natural gas pipeline industry. Automated pipeline compressors in a dozen stations, totalling 100 000 hp or more, may be under the command of a single operator. Rapid developments, particularly in solid-state technology, will permit compressor controls to be more extensive and reliable. With a continuing trend towards more complex plants and processes, more control functions will be automated since manual surveillance alone will find it difficult to provide assured improvement in compressor safety and performance.