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Digitizers on the move
General and Engineering Computer Services Ltd, Liverpool The suite of computer programs is totally interlinked, thereby reducing to a minimum the manual production of information, yet permitting the engineer to intervene at all stages of the design process to over-write and to amend the computerized design. He thus retains full command of, and responsibility for, the design. Seven individual program modules make up the suite:
Mini-size n.c. language
MINIFAPT is a modular programming system following the same syntax as the APT family of languages of which it forms a part. All point-to-point machine operations can be performed as well as cutting flat contours that are composed of linear and circular segments. The system has three subunits consisting of; the processor for decoding the source program instructions; post-processors for translating the results into a language suitable for 1. Master file creation and control the particular machine tool employed; program: stores full details of the additional programs for checking the area, population, discharge per tool trajectories and machinings percapita, permeability, storm frequency, formed using a plotting table. etc. The file is updated by each of The MINIFAPT program consists the subsequent design modules. of a sequence of instructions that define the geometry of the item and 2. Optimization: The gradient of each the nature of the machinings to be perpipe length is selected at least-cost formed. There are several forms of so that the final vertical pipe aligninstructions, including: ment is the most economical. 3. Hydraulic calculations: The diameter 1. Service instructions controlling the evolution of the program. of each pipe-length is selected in accordance with the calculated flows.
4. Pipe strength and class of bedding: The master file retains full details of the route of the sewer and the external loads imposed on each pipe-length. From this ini~ormation the pipe-lengths are individually designed for strength and class of bedding. 5. Automatic drawings: With the completion of the design process the computer has all the information necessary to produce on a drumplotter the longitudinal crosssections to contract drawing standard. 6. Estimates and K29 Form: From a databank the estimated costs can now be produced automatically in accordance with the requirements of the Department of the Environment. 7. Bills of Quantities: These can also be produced automatically in accordance with standard procedures. These programs together form a powerful design process which reduces the Engineer's routine work, affords him more time for exercising his engineering judgement and increases his productivity. The programs are now in use within the practice of Messrs Ward, Ashcroft and Parkman.
Volume 6 Number 1 January 1974
2. Calculation instructions giving values to the arithmetical or geometrical elements. 3. Geometrical instructions, defining points, straight lines, circles etc. 4. Machining instructions, defining the tool employed, spindle and feed speeds etc. 5. Tool movement instructions, such as positioning, incremental or continuous movement. 6. Simplifying instructions for program statements, such as conditional or unconditional branching. macro definitions and call statements for macros. 7. Geometrical transformations for machining (Tracut, copy), or for geometrical elements (Refsys) either directly defined or using matrix definitions. Macros are closed subroutines that are called by CALL statements followed by a list of parameters. The customer may define temporary macros for an immediate use in the part program. He may also store permanent macros on a disc file and recall them in any Minifapt part-program if wanted. In this case, he may delete the stored macros on the disc file. The system can be operated on computers having 8k words storage and one disc unit, which together with a fast processing time, is said to lead to
a very competitive system in terms of performance and cost. Two instructions in MINIFAPT are worth mentioning. Contur defines the contour of the finished item with the programmer simply specifying the departure point, the arrival point and the elements composing the contour. The Cutcom instruction specifies the tool's position in relation to this contour. The tool centre's path is calculated, composed of both linear and circular elements, together with the junction circles when the contour contains sharp corners. The MINIFAPT system was developed by the Centre D'etude de la Commande Numerique and initiated by the Direction des Recherches et Moyens d'Essais. First presented at the Machine Tools Yearly Show in 1970 and marketed since June 1971, the system is now being used in many different branches of the mechanical industry.
Digitizers on the move D-mac are supplying two Digigrid System digitizers to British Rail's Research and Development Division at Derby. The digitizers, each with a display unit, will be coupled to a common interface and connected to the Research and Development Division's GEC905 which is itself a satellite to an IBM 370/145. The new installation will operate under British Rail's BRIGHTPAD software in the 905. The BRIGHTPAD system is a full drafting package and comprises construction facilities, geometric calculations and systems functions, such as filing. Examples of geometric applications include examination of the outside profile of the Advanced Passenger Train (APT) vis-a-vis a loading gauge, the investigation of the dimensions of the wheel tyre checking gauges, and also the investigation of the section properties of a range of new and worn rails suggested for the Channel Tunnel. With some of these geometric layout problems a man/time saving of the order of 40:1 was achieved The Digigrid System-2 digitizers use a solid-state grid table having no moving parts and allow accurate reduction of any analogue or graphic pattern into digital form with a resolution of 0.1 mm. The digitizing surfaces each have an active area of 0.9 m x 1.22 m mounted on pedestals that can be adjusted for height, working angle and rotation.
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Mini-size n.c. language
MINIFAPT is a modular programming system following the same syntax as the APT family of languages of which it forms a part. All point-to-point machine operations can be performed as well as cutting flat contours that are composed of linear and circular segments. The system has three subunits consisting of; the processor for decoding the source program instructions; post-processors for translating the results into a language suitable for 1. Master file creation and control the particular machine tool employed; program: stores full details of the additional programs for checking the area, population, discharge per tool trajectories and machinings percapita, permeability, storm frequency, formed using a plotting table. etc. The file is updated by each of The MINIFAPT program consists the subsequent design modules. of a sequence of instructions that define the geometry of the item and 2. Optimization: The gradient of each the nature of the machinings to be perpipe length is selected at least-cost formed. There are several forms of so that the final vertical pipe aligninstructions, including: ment is the most economical. 3. Hydraulic calculations: The diameter 1. Service instructions controlling the evolution of the program. of each pipe-length is selected in accordance with the calculated flows.
4. Pipe strength and class of bedding: The master file retains full details of the route of the sewer and the external loads imposed on each pipe-length. From this ini~ormation the pipe-lengths are individually designed for strength and class of bedding. 5. Automatic drawings: With the completion of the design process the computer has all the information necessary to produce on a drumplotter the longitudinal crosssections to contract drawing standard. 6. Estimates and K29 Form: From a databank the estimated costs can now be produced automatically in accordance with the requirements of the Department of the Environment. 7. Bills of Quantities: These can also be produced automatically in accordance with standard procedures. These programs together form a powerful design process which reduces the Engineer's routine work, affords him more time for exercising his engineering judgement and increases his productivity. The programs are now in use within the practice of Messrs Ward, Ashcroft and Parkman.
Volume 6 Number 1 January 1974
2. Calculation instructions giving values to the arithmetical or geometrical elements. 3. Geometrical instructions, defining points, straight lines, circles etc. 4. Machining instructions, defining the tool employed, spindle and feed speeds etc. 5. Tool movement instructions, such as positioning, incremental or continuous movement. 6. Simplifying instructions for program statements, such as conditional or unconditional branching. macro definitions and call statements for macros. 7. Geometrical transformations for machining (Tracut, copy), or for geometrical elements (Refsys) either directly defined or using matrix definitions. Macros are closed subroutines that are called by CALL statements followed by a list of parameters. The customer may define temporary macros for an immediate use in the part program. He may also store permanent macros on a disc file and recall them in any Minifapt part-program if wanted. In this case, he may delete the stored macros on the disc file. The system can be operated on computers having 8k words storage and one disc unit, which together with a fast processing time, is said to lead to
a very competitive system in terms of performance and cost. Two instructions in MINIFAPT are worth mentioning. Contur defines the contour of the finished item with the programmer simply specifying the departure point, the arrival point and the elements composing the contour. The Cutcom instruction specifies the tool's position in relation to this contour. The tool centre's path is calculated, composed of both linear and circular elements, together with the junction circles when the contour contains sharp corners. The MINIFAPT system was developed by the Centre D'etude de la Commande Numerique and initiated by the Direction des Recherches et Moyens d'Essais. First presented at the Machine Tools Yearly Show in 1970 and marketed since June 1971, the system is now being used in many different branches of the mechanical industry.
Digitizers on the move D-mac are supplying two Digigrid System digitizers to British Rail's Research and Development Division at Derby. The digitizers, each with a display unit, will be coupled to a common interface and connected to the Research and Development Division's GEC905 which is itself a satellite to an IBM 370/145. The new installation will operate under British Rail's BRIGHTPAD software in the 905. The BRIGHTPAD system is a full drafting package and comprises construction facilities, geometric calculations and systems functions, such as filing. Examples of geometric applications include examination of the outside profile of the Advanced Passenger Train (APT) vis-a-vis a loading gauge, the investigation of the dimensions of the wheel tyre checking gauges, and also the investigation of the section properties of a range of new and worn rails suggested for the Channel Tunnel. With some of these geometric layout problems a man/time saving of the order of 40:1 was achieved The Digigrid System-2 digitizers use a solid-state grid table having no moving parts and allow accurate reduction of any analogue or graphic pattern into digital form with a resolution of 0.1 mm. The digitizing surfaces each have an active area of 0.9 m x 1.22 m mounted on pedestals that can be adjusted for height, working angle and rotation.
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