MPCNC milling post processor for Autodesk Fusion 360

MPCNC.cps.js

/**
 * Global info
 */

description = "MPCNC";
longDescription = "Basic MPCNC milling post processor.";
vendor = "V1 Engineering";
vendorUrl = "https://www.v1engineering.com";

extension = "gcode";
setCodePage("ascii");
capabilities = CAPABILITY_MILLING;

minimumChordLength = spatial(0.01, MM);
minimumCircularRadius = spatial(0.01, MM);
maximumCircularRadius = spatial(1000, MM);
minimumCircularSweep = toRad(0.01);
maximumCircularSweep = toRad(180);
allowHelicalMoves = false;
allowedCircularPlanes = undefined;

/**
 * User defined properties
 */

properties = {};
propertyDefinitions = {};
var PROPERTY = {};
var propertyNumber = 100;

function newProperty(id, value, definition) {
  // Use numerical names to get a pretty ordered list
  var name = "_" + (propertyNumber++) + "_" + id.toLowerCase();
  PROPERTY[id] = name;
  properties[name] = value;
  propertyDefinitions[name] = definition;
}

var TARGET = {
  SDCARD: "sdcard",
  REPETIER: "repetier",
};

newProperty("TARGET", TARGET.SDCARD, {
  title: "Target",
  type: "enum",
  values: [
    {id: TARGET.SDCARD, title: "SD card"},
    {id: TARGET.REPETIER, title: "Repetier-Host"},
  ],
});

var ORIGIN = {
  MACHINE: "machine",
  START: "start",
  MANUAL: "manual",
};

newProperty("ORIGIN", ORIGIN.START, {
  title: "Origin",
  type: "enum",
  values: [
    {id: ORIGIN.MACHINE, title: "Machine (homing)"},
    {id: ORIGIN.START, title: "Initial position"},
    {id: ORIGIN.MANUAL, title: "Manual (pre-calibrated)"},
  ],
});

newProperty("MANAGE_SPEED", true, {
  title: "Spindle speed changes",
  description: "Pause program to prompt user to change spindle speed.",
  type: "boolean"
});

newProperty("TOOLCHANGE_X", 50, {
  title: "Tool changing X",
  description: "X location for tool changes.",
  type: "integer",
});

newProperty("TOOLCHANGE_Y", 50, {
  title: "Tool changing Y",
  description: "Y location for tool changes.",
  type: "integer",
});

newProperty("TOOLCHANGE_Z", 20, {
  title: "Tool changing Z",
  description: "Z location for tool changes.",
  type: "integer",
});

newProperty("RAPID_XY", 2500, {
  title: "Travel speed XY (mm/min)",
  description: "Speed for rapid movements in X or Y directions.",
  type: "integer",
});

newProperty("RAPID_Z", 300, {
  title: "Travel speed Z (mm/min)",
  description: "Speed for rapid movements in Z direction.",
  type: "integer",
});

/**
 * Helpers
 */

var isSpindleOn = null;
var spindleSpeed = null;
var didAutoHome = false;
var displayMessage = null;

var xyzFormat = createFormat({decimals: 3});
var feedFormat = createFormat({decimals: 0});

var sFormat = createFormat({prefix: " S", decimals: 0});
var pFormat = createFormat({prefix: " P", decimals: 0});

var xVariable = createVariable({prefix:" X"}, xyzFormat);
var yVariable = createVariable({prefix:" Y"}, xyzFormat);
var zVariable = createVariable({prefix:" Z"}, xyzFormat);
var fVariable = createVariable({prefix:" F"}, feedFormat);

var iVariable = createReferenceVariable({prefix:" I"}, xyzFormat);
var jVariable = createReferenceVariable({prefix:" J"}, xyzFormat);
var kVariable = createReferenceVariable({prefix:" K"}, xyzFormat);

function writeComment(text) {
writeln("; " + text);
}

function writeHeader(title) {
  writeln("");
  writeComment("====== " + title + " ======");
}

function display(message) {
  if (properties[PROPERTY.TARGET] == TARGET.REPETIER) {
    // Repetier-Host does not handle M117 well, so skip it completely
    return;
  }
  writeln("M117 " + message);
  // Store display message to repeat it after a user prompt
  displayMessage = message;
}

function beep(comment) {
  writeln("M300 P30" + (comment ? " ; " + comment : ""));
}

function multiBeep(count, pause, comment) {
  for (var i = 0; i < count; i++) {
    if (i > 0) writeln("G4" + pFormat.format(pause));
    beep(comment);
    comment = null;
  }
}

function multiMultiBeep(count, pause, count2, pause2, comment) {
  for (var i = 0; i < count2; i++) {
    if (i > 0) writeln("G4" + pFormat.format(pause2));
    multiBeep(count, pause, comment);
    comment = null;
  }
}

function promptUser(message) {
  writeln("M400 ; finish moves");
  if (properties[PROPERTY.TARGET] == TARGET.REPETIER) {
    // @pause does some movements, save/restore origin to prevent this
    var x = xVariable.getCurrent();
    var y = yVariable.getCurrent();
    var z = zVariable.getCurrent();
    writeln("G92 X0 Y0 Z0 ; reset origin for @pause");
    xVariable.reset();
    yVariable.reset();
    zVariable.reset();
    writeln("@pause " + message);
    x = xVariable.format(x);
    y = yVariable.format(y);
    z = zVariable.format(z);
    if (x || y || z) writeln("G92" + x + y + z + " ; restore after @pause");
    fVariable.reset();
  } else {
    beep("short beep to inform user")
    writeln("M0 " + message);    
    if (displayMessage) display(displayMessage);
  }
}

function ensureSpindleOn(speed) {
  speed = clamp(5000, speed, 25000);
  if (properties[PROPERTY.MANAGE_SPEED] && (spindleSpeed === null || Math.abs(spindleSpeed - speed) >= 1000)) {
    ensureSpindleOff();
    var kressSetting = Math.round((speed - 500) / 4000);
    promptUser("Set speed " + kressSetting + " (" + speed + " RPM)");
    writeln("G4 S1 ; wait after click");    
  }
  spindleSpeed = speed;
  
  if (isSpindleOn === true) return;
  writeln("M400 ; finish moves");
  if (properties[PROPERTY.TARGET] == TARGET.REPETIER) {
    writeln("@sound");
  } else {
    multiMultiBeep(3, 100, 3, 200, "sound warning alarm");
  }
  writeln("G4 S1 ; wait after alarm");
  writeln("M106 ; turn on spindle");
  writeln("G4 S3 ; wait for spindle to ramp up");
  isSpindleOn = true;
}

function ensureSpindleOff(skipWait) {
  if (isSpindleOn === false) return;
  writeln("M400 ; finish moves");
  writeln("M107 ; turn off spindle");
  if (!skipWait) {
    // We need a second of time for each 5000 RPM
    var waitTime = spindleSpeed ? Math.round(spindleSpeed / 5000) : 0;
    writeln("G4" + sFormat.format(waitTime) + " ; wait for spindle to ramp down");
  }
  isSpindleOn = false;
}

function autoHome() {
  display("Auto homing");
  ensureSpindleOff();
  
  writeln("G28 ; auto home to touch plate");
  xVariable.reset();
  yVariable.reset();
  zVariable.reset();

  var z = zVariable.format(5);
  var f = fVariable.format(properties[PROPERTY.RAPID_Z]);
  writeln("G1" + z + f + " ; back off a bit");
  fVariable.reset();

  didAutoHome = true;
}

function moveForToolChange() {
  // It's only safe to move when we've already homed before
  if (didAutoHome) {
    onRapid(properties[PROPERTY.TOOLCHANGE_X], properties[PROPERTY.TOOLCHANGE_Y], properties[PROPERTY.TOOLCHANGE_Z]);
  }
}

function toolChange(tool) {
  writeHeader("Tool change: #" + tool.number + " (" + tool.getDescription() + ")");
  ensureSpindleOff(true);
  
  moveForToolChange();
  
  writeln("M18 Z ; disable Z stepper");
  promptUser("Insert " + tool.getDescription());  
  autoHome();
}

/**
 * Post processor callbacks
 */

function onOpen() {
  if (getToolTable().getNumberOfTools() > 1 && properties[PROPERTY.ORIGIN] != ORIGIN.MACHINE) {
    error("Machine origin is required when using multiple tools");
  }
  
  if (unit != MM) {
    error("Only millimeter units are supported");
  }
}

function onClose() {
  writeHeader("Termination");
  ensureSpindleOff(true);
  moveForToolChange();
  display("Job done");
  writeln("M18 ; disable steppers");
}

function onSection() {
  if (isFirstSection()) {
    writeHeader("Initialization");
    ensureSpindleOff(true);
    
    writeln("G90 ; absolute positioning");
    writeln("G21 ; millimeter units");
    writeln("M18 S0 ; disable stepper timeouts");

    if (properties[PROPERTY.ORIGIN] == ORIGIN.START) {
      writeln("G92 X0 Y0 Z0 ; set origin to initial position");
    }
  }

  if (isFirstSection()
    || (currentSection.getForceToolChange && currentSection.getForceToolChange())
    || tool.number != getPreviousSection().getTool().number
  ) {
    toolChange(tool)
  }
  
  var title = getParameter("operation-comment")
  
  writeHeader("Operation: " + title);
  display(title);
  var initialPosition = currentSection.getInitialPosition();
  onRapid(initialPosition.x, initialPosition.y, initialPosition.z);
  
  ensureSpindleOn(currentSection.getInitialSpindleSpeed());
}

function onSectionEnd() {
  xVariable.reset();
  yVariable.reset();
  zVariable.reset();
  fVariable.reset();
}

function onParameter(name, value) {
  switch (name) {
    case "generated-by":
      writeComment("Generated by: " + value);
      break;
    case "generated-at":
      writeComment("Generated at: " + value + " (GMT)");
      writeComment("Posts processor: " + FileSystem.getFilename(getConfigurationPath()));
      for (var i = 0; i < propertyDefinitions[PROPERTY.TARGET].values.length; i++) {
        if (propertyDefinitions[PROPERTY.TARGET].values[i].id !== properties[PROPERTY.TARGET]) continue;
        writeComment("Target: " + propertyDefinitions[PROPERTY.TARGET].values[i].title);
      }
      break;
    case "document-path":
      writeComment("File: " + value);
      break;
    case "job-description":
      writeComment("Setup: " + value);
      break;
    case "print":
    case "display":
      writeHeader("Display on screen");
      display(value);
      break;
  }
}

function onRapid(x, y, z) {
  var zGoingDown = z < zVariable.getCurrent();
  
  x = xVariable.format(x);
  y = yVariable.format(y);
  z = zVariable.format(z);

  if (z && !zGoingDown) {
    var f = fVariable.format(properties[PROPERTY.RAPID_Z]);
    fVariable.reset();
    writeln("G1" + z + f);
  }

  if (x || y) {
    var f = fVariable.format(properties[PROPERTY.RAPID_XY]);
    fVariable.reset();
    writeln("G1" + x + y + f);
  }

  if (z && zGoingDown) {
    var f = fVariable.format(properties[PROPERTY.RAPID_Z]);
    fVariable.reset();
    writeln("G1" + z + f);
  }
}

function onLinear(x, y, z, feedrate) {
  x = xVariable.format(x);
  y = yVariable.format(y);
  z = zVariable.format(z);
  if (!x && !y && !z) return;
  f = fVariable.format(feedrate); // Make sure this line is below the return
  writeln("G1" + x + y + z + f);
}

function onCircular(clockwise, cx, cy, cz, x, y, z, feedrate) {
  switch (getCircularPlane()) {
    case PLANE_XY:
      var command = clockwise ? "G2" : "G3";
      var start = getCurrentPosition();
      var i = iVariable.format(cx - start.x, 0);
      var j = jVariable.format(cy - start.y, 0);
      x = xVariable.format(x);
      y = yVariable.format(y);
      f = fVariable.format(feedrate);
      writeln(command + " " + x + y + i + j + f);
      break;
    default:
      linearize(tolerance);
  }
}

function onComment(comment) {
  writeHeader("Comment");
  writeComment(comment);
}

function onDwell(seconds) {
  writeHeader("Dwell");
  writeln("G4" + sFormat.format(seconds) + " ; wait for " + seconds + " seconds");
}

function onPassThrough(value) {
  writeHeader("PassThrough");
  writeln(value);
}