Arcuate movement numerical control method and system

The method of producing actual relative movement along two coordinate axes within an acceptable deviation and velocity error of a commanded path having a commanded velocity comprising the steps of subdividing the movement into a plurality of successive lengths, normally providing a plurality of different possible extents for each length with the extent of each possible length being defined by a number of increments on each axis and with each possible length being no more than a set number of increments on each axis from the extents of the immediately prior length, selecting the possible extent which would produce a movement that both minimizes the deviation from the commanded path and minimizes the error in velocity from the commanded velocity and producing a relative movement of the selected extent of the length with the movement for each length occurring over the same constant time interval for each length.

The method of producing actual relative movement along two coordinate axes within an acceptable deviation from a commanded arcuate path comprising the steps of subdividing the arcuate movement into a plurality of successive linear lengths, selecting the direction and extent of each length to that which would produce a movement which would be within the acceptable deviation and which also has a relationship with its immediately prior length and producing a relative movement for the extent of each length and in which each length is defined as a number of increments of movement on each axis to be produced simultaneously during a time interval and in which the step of selecting causes the relationship between successive lengths to have an extent that has the number of increments on each axis to be within an absolute numerical value of each other.

An apparatus for producing actual relative movement along two coordinate axes within a minimum deviation from a commanded path comprising motor means connected to each axis for producing a determined extent of movement with the determined extents for each axis being essentially simultaneously produced, means for receiving information of the commanded path, means for subdividing the commanded path into a plurality of actual successive lengths with the lengths constituting the actual movement, means for normally selecting a plurality of different possible lengths for each length with each possible length having an extent on each axis which is within an absolute numerical value from the extents of the immediately prior length, means for determining the one possible length which produces the least deviation from the commanded path, and means for directing the determined length as a determined extent on each axis to its respective axis motor means to produce the actual length with the movement for each length occurring over the same constant time interval for each length.

An apparatus for providing actual relative movement along two coordinate axes within an acceptable deviation and velocity error from a commanded path and velocity comprising motor means connected to each axis for producing a determined extent of movement with the determined extent for the axes being essentially simultaneously produced, means for receiving information of the commanded path and velocity, means for subdividing the commanded path into a plurality of actual successive lengths with the lengths constituting the actual movement, means for normally selecting a plurality of different possible lengths for each length with each possible length having an extent on each axis which is within an absolute numerical value from the extents of the immediately prior length, means for determining the one possible length which produces the least combination of path deviation and velocity error from the commanded path and velocity and means for directing the determined length as a determined extent on each axis to its respective axis motor means to produce the actual length with the movement for each length occurring over the same constant time interval for each length.

An apparatus for providing actual relative movement along two coordinate axes within an acceptable deviation from a commanded arcuate path comprising motor means connected to each axis for translating each pulse received essentially simultaneously into an increment of movement in accordance with a direction signal, means for receiving information of the commanded arcuate path, means for subdividing the commanded path into a plurality of successive lengths with the lengths constituting the actual movement, means for normally selecting a plurality of different possible extents for each length with the extent of each possible length being defined by a number of increments on each axis and with each possible length being no more than a set number of increments on each axis from the extents of the immediately prior length, means for determining one possible extent which produces an acceptable deviation from the commanded path, means for determining for each extent the deviation of the extent along each axis, means for producing the determined extent as a length defined by a number of pulses and a direction signal to their associated motor means to produce the actual length with the movement for each length occurring over the same constant time interval for each length.