Contouring control system employing ramp staircasing of position points

A control system for positioning a machine member in accordance with a set of predetermined input instructions corresponding to a prescribed path of movement of said machine member comprising:

• motor driving means operatively connected to said machine member to drive the same in at least two mutually perpendicular directions;
• pulse generating means for generating separate trains of pulses corresponding to magnitudes of coordinates in said directions of points along a prescribed path, said pulse generating means being operatively connected to said motor driving means for actuating the same by the respective trains of pulses;
• and
• a contour logic circuit means connected to said pulse generating means and arranged to detect deviation from said prescribed path, said contour logic circuit being connected to said motor driving means for enabling the same to respond to pulses applied thereto by said pulse generating means whereby a portion of said motor driving means drives said machine member continuously in one of said directions and permits another portion of said motor drive means to drive said machine member in another direction only when said machine member arrives at or overshoots said path, said contour logic circuit means comprising:
• a first and second coordinate register respectively arranged to receive data corresponding to magnitudes of coordinates in said two directions respectively;
• an error register means for generating data corresponding to deviations between magnitudes of coordinates prescribed by the instructions and magnitudes of coordinates of present location in which said first and second motor driving means actually move said machine member;
• and
• a logic circuit means connected in circuit with said coordinate registers and said error register means to enable either motor driving means selectively to drive said machine member in either direction depending on the particular deviations determined by said error register means.