A Microprocessor controller to Provide Low Cost Numerical Control
The cost effectiveness and flexibility of microprocessors, used as central processing units, will result in their replacing many of the numerical and computer numerical controls used in the machine tool industry. Further, microprocessors can now be used to provide the control of some processes which formerly did not warrant fully the capital expense of numerical controls.
Two such processes, electron beam welding and cutter grinding are considered here and microprocessor controls developed for them. The controls were developed with low cost and ease of operator use as primary objectives. For both processes contour generation is required in the positioning of an open-loop system. With the electron beam welder, beam deflection is achieved in two axes with compensation made for change in workpiece height. Cutter grinding is achieved using three step-motor driven axes on an attachment to a universal cutter grinding machine. The contour generation has been achieved primarily in software and demonstrates excellent performance characteristics in terms of speed and accuracy. Part-programming facilities are considered for the two systems, as too are methods whereby the cost of peripheral equipment, for data input, can be reduced.
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