Table of Contents

Glossary: Machining Step

What Is a Machining Step?

A MachiningStep (MachiningStep) is a single computation unit in the HiNC simulation. By default, one step corresponds to one spindle revolution, but this interval is configurable via the Basic Simulation workflow.

Each step contains data for the time interval between two consecutive steps (from the previous step to the current step). Since this represents a period rather than an instant, many fields are simplified representations using prefixes like Average (Avg), Extremes (Min, Max), Range (Delta), and Maximum Absolute Value (MaxAbs).

Key Properties

The table below summarizes the primary step output fields. For the complete reference, see MachiningStep.

Basic Source Information

Property Description
FileNo / LineNo / FilePath / LineText Source NC file and line information
StepIndex Step sequence index
ToolId Active tool ID
FlagsText Active G-code modal flags

Time and Motion

Property Description
AccumulatedTime Accumulated simulation time
StepDuration Duration of this step
BeginSpindleAngle_deg Spindle angle at step start
Cl (X, Y, Z, I, J, K) Cutter location point and tool axis vector
MC (X, Y, Z, A, B, C) Machine coordinates
Feedrate_mmdmin Feed rate (mm/min)
SpindleSpeed_rpm Spindle speed (RPM)
FeedPerTooth_mm / FeedPerCycle_mm Feed per tooth / per cycle
MovingLength_mm Displacement length

Cutting Engagement

Property Description
IsTouched Whether cutting engagement occurred
CuttingWidth_mm (ae) Cutting width
CuttingDepth_mm (ap) Cutting depth
Mrr_mm3ds Material removal rate
ChipThickness_mm Chip thickness
ChipVolume_mm3 Chip volume

Force and Torque

Property Description
AvgForceToToolOnToolRunningCoordinate_N Average force on tool (X, Y, Z)
MaxAbsForce_N Maximum absolute force
AvgAbsTorque_Nm Average absolute torque

Power and Energy

Property Description
SpindleInputPower_W Spindle input power
SpindleOutputPower_W Spindle output power (after efficiency losses)
MaxSpindlePowerRatio Input power / max spindle power capability
AccumulatedSpindleEnergyConsumption_kWh Accumulated energy consumption

Thermal

Property Description
CutterDermisTemperature_C Cutter surface temperature
WorkpieceDermisTemperature_C Workpiece surface temperature
ChipTemperature_C Chip temperature
ThermalStress_MPa / ThermalYieldRatio Thermal stress and yield ratio

Wear and Deflection

Property Description
AccumulatedCraterWear_um Accumulated crater wear
AccumulatedFlankWearDepth_um / Width_um Accumulated flank wear
ReCutDepth_um Re-cut depth from tool deflection

Registering Custom Step Variables

Beyond default properties, you can register custom step variables using RegisterStepVariable:

RegisterStepVariable(
    "ChipVolume",          // key
    "Chip Volume",         // display name
    "mm3",                 // unit
    "F2",                  // format string
    (step) => step.ChipVolume_mm3  // value function
);

PlayNcFile("NC/file1.nc");

Parameters:

  • key: Unique identifier
  • name: Display name (shown in UI)
  • unit: Physical unit (can be null)
  • formatString: .NET numeric format string (can be null)
  • variableFunction: Lambda that computes the value from a step (can be null)

Registered variables appear in the UI and in output files from WriteStepFiles.

Indexer Access

Use the this[string] indexer to read/write custom data on a step:

SessionStepBuilt += (preStep, curStep) => {
    if (curStep != null)
        curStep["MyCustomField"] = someCalculation();
};

Accessing Step Data

GetMillingStep

GetMillingStep retrieves a step by index:

var step = GetMillingStep(100);
if (step != null)
{
    Message($"ToolId={step.ToolId}, Force={step.MaxAbsForce_N} N");
}

StepCount

StepCount returns the total number of steps:

Message($"Total steps: {StepCount}");

Iterating All Steps

for (int i = 0; i < StepCount; i++)
{
    var step = GetMillingStep(i);
    // process step...
}

Step Output Files

Steps can be exported to CSV using WriteStepFiles:

WriteStepFiles("Output/[NcName].step.csv");

The CSV contains all default properties plus any registered custom variables. The file can be read back with PlayCsvFile.

For waveform-level data (sub-step time resolution), use WriteShotFiles:

WriteShotFiles("Output/[NcName].shot.csv", 1);  // 1 ms time resolution

Dynamically Registered Variables (Training)

After executing TrainMillingPara or ReTrainMillingPara, two additional step variables are automatically registered for steps within the training region:

Variable Description
TrainingErrRatio Error metric between simulation and measurement for each step
AngleOffset Cutter rotation phase difference between measured and simulated data

See Also