Browsing by Author "Rodd, Michael Godfrey"

Now showing 1 - 6 of 6
  • Thumbnail Image
    Item
    Open Access
    Computerised evaluation of furnace fields
    (1974) Rabey, Christopher Charles; Rodd, Michael Godfrey
    The concept of using a submerged arc furnace for the reduction of ore to semi-refined metal was introduced early in the nineteenth century, and although much research has been done on the operation of the furnace, its design and construction still remain more of an art than a science. The aim of this thesis is to investigate, by means of various models, some of the basic parameters and fields of the arc furnace in an attempt to increase the understanding of its operation.
  • Thumbnail Image
    Item
    Open Access
    Direct digital control of thyristor networks : an investigation into the on-line control of thyristor networks by means of a small digital computer
    (1970) Rodd, Michael Godfrey; Enslin, NC de V
    This thesis is an investigation into the applications of a digital computer to the on-line control of thyristor networks. This will involve producing hardware and software to determine firing sequences, firing delays, etc., and to execute the firing instructions. These are to be determined by the computer from the initial instructions and information fed back from the system, correlated with information in the memory. The ultimate aim is geared towards the control of induction motors, based on research work at present being carried out under Professor N.C.Enslin, at the University of Cape Town, on the speed control of induction motors by thyristor networks.
  • Thumbnail Image
    Item
    Open Access
    A high speed data link
    (1974) Thorning, Gerald Peter; Rodd, Michael Godfrey
    Work done on a Varian 6201 computer in the field of automation and control showed the need for high-speed data terminals that would extend the use of the Varian to remote processes.
  • Thumbnail Image
    Item
    Open Access
    An industrialized microprocessor system
    (1976) Bloch, Gerald; Rodd, Michael Godfrey
    The aim of this project is to design and build an industrialized microprocessor system capable of testing the limits and capabilities of microprocessors in the industrial process control world. The system must be capable of operating in a data logging or control or supervisory capacity. The system consists of a ruggerdized, electrically isolated unit, designed on a "black box" principle, with minimum operator controls. It is housed in a sealed crate with internal access via rows of input and output plugs and connecters. The system has been designed on a modular basis in order to simplify expansion. It can be operated as a small dedicated controller or expanded by the addition of memory and/or industrial I/O modules to its full capacity. The system is based on an INTEL 8080 microprocessor. The industrial interface consists of electrically isolated analog and digital input and output modules which can be selected under program control. There are also up to 64 asynchronous priority encoded alarm channels that can interrupt the control sequence at any time should an alarm condition arise. For debugging hardware and software a plug-on front panel unit is provided.
  • Thumbnail Image
    Item
    Open Access
    An industrialized microprocessor system
    (1976) Block, Gerald; Rodd, Michael Godfrey
    The aim of this project is to design and build an industrialized microprocessor system capable of testing the limits and capabilities of microprocessors in the industrial process control world. The system must be capable of operating in a data logging or control or supervisory capacity. The system consists of a ruggerdized, electrically isolated unit, designed on a "black box" principle, with minimum operator controls. It is housed in a sealed crate with internal access via rows of input and output plugs and connecters. The system has been designed on a modular basis in order to simplify expansion. It can be operated as a small dedicated controller or expanded by the addition of memory and/or industrial I/O modules to its full capacity. The system is based on an INTEL 8080 microprocessor. The industrial interface consists of electrically isolated analog and digital input and output modules which can be selected under program control. There are also up to 64 asynchronous priority encoded alarm channels that can interrupt the control sequence at any time should an alarm condition arise. For debugging hardware and software a plug-on front panel unit is provided.
  • Thumbnail Image
    Item
    Open Access
    Organization of industrial control computers
    (1976) Rodd, Michael Godfrey; Enslin, NC de V; MacGregor, Ken
    The efficient use of industrial control computers is recognized as an organizational problem akin to the traffic-switching problem in communications. A systematic approach to this problem is proposed, based on theory developed for the handling of telephone traffic. The application of the approach indicates that it is necessary to re-evaluate traditional hardware/software relationships. A change in these relationships is desirable, since multi-programmed computers spend too much time in handling their own organization. This situation is compounded in time-critical industrial process-control applications. It is proposed that the solution lies in the use of a flexible hardware operating system, working in close relationship with a conventional minicomputer. The unit proposed to implement this function, termed a microcontroller, makes use of the new bipolar microprocessor elements and provides a high-speed, flexible control unit, adaptable to user requirements. To retain a high degree of flexibility the microcontroller is microprogrammable. In essence, the unit executes the principal functions of a real-time operating system, acts as a pre-processor for all incoming requests, and ensures a high rate of task-switching. This system is applied to a series of configurations, each selected to demonstrate, quantitatively, the value of the technique in real applications. Comparisons are made between real-time control configurations based on the software-implemented approach and the identical configurations based on this system. The proposed strategy is shown to result in a better and more economical industrial controller. The wider implication for any aspect of organization is that "bigger" is not necessarily "better". Successful management implies effective use of facilities, rather than a proliferating structure.