Distributed logic control system and method

A machine control system which comprises, in combination, a machine including motion-producing means for producing motion at said machine and condition-sensing means for sensing machine conditions, and control means responsive to a predefined input from said condition-sensing means for providing a predefined output to said motion-producing means, characterized in that said control means comprises:

• means for tabulating said predefined input and output in a combination representative of a preselected set of operations of said machine, each said combination representing an input/output image indicative of a corresponding zone in said preselected set;
• means for monitoring said predefined input and output responsive to a change in said predefined input and output to formulate a new input/output image;
• means for comparing said new input/output image to an input/output image in said tabulating means wherein said means for comparing indicates a next zone in said preselected set;
• means for indicating an error condition in the event that said new input/output image does not match that of a next zone in said preselected set;
• and
• means for initiating operation of said machine at each corresponding zone of said preselected set, illumination means associated with each said initiating means, and energizing means for energizing said illumination means at a state of a plurality of illumination states to indicate one of a plurality of available operating modes at said machine.

A method of operating a machine capable of performing a plurality of physical operations in a preselected sequence wherein said machine is controlled through input and output devices, said method comprising the steps of:

• establishing a set of machine operations defined by a set of operating zones, each zone of said operating zones having a corresponding input/output image of inputs and outputs from said input and output devices and each zone having a corresponding allowed next zone with at least one of said operating zones having a plurality of allowed next zones;
• monitoring inputs and outputs from said input and output devices during a step in said plurality of physical operations and comparing said inputs and outputs to said corresponding input/output image associated with said step;
• advancing machine operation to a next step in said set of machine operations when a change in said inputs and outputs produces a zone image corresponding to said allowed next zone;
• and
• indicating an error condition when a change in said inputs and outputs produces a zone image other than that corresponding to said allowed next zone.

A method of controlling a machine mechanism for obtaining a single non-interfering machine motion through an operating sequence, said method comprising the steps of:

• (a) coupling input/output means to said machine mechanism for providing input/output signals which vary as a function of motion of said machine mechanism through said sequence;
• (b) establishing a plurality of distinct mechanism operating zones each characterized by a combination of said input/output signals and each having associated therewith an allowed next operating zone, said operating zone including at lest two zones corresponding respectively to one or more operating states of said machine mechanism and an error zone, and at least one of said operating zones is associated with a plurality of next operating zones;
• (c) monitoring said input/output signals in each of said plurality of distinct mechanism operating zones for the combination of said input/output signals corresponding to said allowed next operating zone;
• (d) advancing machine operation to said allowed next operating zone upon detection of a corresponding input/output signal combination;
• and
• (e) advancing machine operation to said error zone and indicating an error condition upon detection of a combination of an input/output signal other than an input/output signal corresponding to a subsequent mechanism operating zone.

An apparatus for controlling a machine comprising:

• memory means for storing at least two input/output images, each input/output image having associated therewith a present zone and an allowed next zone with at least one input/output image having associated therewith a plurality of allowed next zones;
• monitoring means for receiving an input requiring a change in a present input/output image to a new input/output image;
• means for comparing an input/output image of said allowed next zone with said new input/output image;
• means for executing said input and for replacing said present input/output image with said input/output image of said allowed next zone if said new input/output image matches said allowed next none;
• and
• means for indicating an error condition when said new input/output image does not match said input/output image of said allowed next zone.

A method for controlling a machine having a present zone, an input/output image of said present zone, and at least two allowed next zones, wherein said method comprises the steps of:

• receiving an input representative of a new input/output image of said machine;
• comparing an input/output image of a first allowed next zone of said at least two allowed next zones with said new input/output image;
• changing said present zone to said first allowed next zone if said input/output image of said first allowed next zone matches said new input/output image;
• and
• comparing an input/output image of a second allowed next zone of said at least two allowed next zones with said new input/output image if said new input/output image did not match said input/output image of said first allowed next zone.

A method for controlling a machine having a present zone, an input/output image of said present zone, and a plurality of allowed next zones, wherein said method comprises the steps of:

• (a) receiving an input representative of a new input/output image of said machine;
• (b) comparing an input/output image of a particular allowed next zone of said plurality of allowed next zones with said new input/output image;
• (c) changing said present zone of said machine to said particular allowed next zone if said input/output image of said particular allowed next zone matches said new input/output image;
• and
• (d) repeating steps (b) and (c) if said input/output image of said particular allowed next zone does not match said new input/output image until all of said plurality of allowed next zones have been compared to said new input/output image.