mcbuilder is the machine builder of linuxcncMulti, modelled on SINUMERIK’s Create MyVirtual Machine /3D Builder. A machine is built as a kinematic tree in a *.mcm file (JSON); the same file drives the 3D view, material removal and collision check of mchmi and is exported as the LinuxCNC configuration, so a machine is described in one place. It is started with mcbuilder [model.mcm]; mcbuilder model.mcm --export DIR writes the configuration without the window (man page mcbuilder(1)).

Window

  • Left: the kinematic tree with a toolbar that adds a node of each type under the selected one, an eye column that hides a subtree, drag and drop to re-hang nodes, a context menu with copy/cut/paste/delete (Ctrl+C/X/V, Entf) and undo/redo (Ctrl+Z/Y). Below it the properties of the selected node.

  • Centre: the 3D preview (orbit with the mouse, zoom with the wheel, camera buttons Iso/Vorne/Hinten/Links/Rechts/Oben, "Alles" fits the machine). The selected subtree is highlighted, tool slots and mount positions show their frames.

  • Right: the pages Simulation (a slider and entry per axis, filter, reset), Bibliothek (parametric components), Kollisionsgruppen, Ebenen (layers) and INI (free INI keys, INI preview).

Nodes

Coordinates are millimetres in a right-handed world frame with Z up. Every node has a position and a roll/pitch/yaw orientation in its parent’s frame (R = Rz(yaw) Ry(pitch) Rx(roll)); an axis node moves its subtree along or about its axis vector, given in the node’s own frame.

Node Meaning Properties

Translationsachse

linear axis

axis vector, min/max, initial value, velocity, acceleration, home position / switch offset / search velocity / sequence ([JOINT_n]HOME*), joint number, channel, letter, optional HAL pin instead of an NC joint, coupling to a driving axis with a ratio

Rotationsachse

rotary axis

as above; rollover for endless axes, Schwenkachse marks a swivel head whose TRAORI data set is derived from the geometry

Spindel

work or milling spindle

rotary axis with the spindle number, maximum speed, counter-spindle flag; with a joint number it is also the C axis

Revolver/Magazin

tool carrier

stations, active station (the cutting position), channel ("tool unit"), magazine number, driven-tool spindle, pitch radius; "Werkzeugaufnahmen erzeugen" places the tool slots on the pitch circle

Geometrie

a machine part

primitive shape (box, cylinder, tube, n-gon, cone with axis) or STL file (ASCII or binary), colour

Werkzeugaufnahme

tool slot

kind (station of a turret, spindle place, magazine place), channel, magazine, slot number, holder transformation. The tool tip is the slot origin, the tool body lies along the slot’s +Z

Montageposition

workpiece on a spindle

workpiece number ([WORKPIECE_n]), spindle, direction of the part, chuck output (motion.digital-out-N), chuck data, blank diameter and length

Gruppe

transformation for its children

Signal / Schalter

a HAL pin switches subtrees

pin name and default value; the switch with the matching trigger value is shown

The library inserts ready-made subtrees under the selected node: milling spindle (taper, length, diameter), work spindle with chuck, chuck, VDI turret with its stations, disc magazine, swivel head (B about Y with a milling spindle pointing down), linear axis, bed, column, slide, tailstock. The example configs/sim/multichannel/index_g200/index_g200.mcm is the INDEX G200 of the simulation built from these components.

Import of a vismach model module (new)

The hand-written models of mchmi ([DISPLAY]MACHINE_MODEL = _model.py, a Python module whose build(j, …​) returns a vismach tree) are opened in the builder with Datei > Python-Modell importieren, Datei > Oeffnen on a .py file or mcbuilder model.py; mcbuilder model.py --convert [OUT.mcm] converts without the window (the file goes beside the module unless OUT is given), --export DIR exports the imported model straight away. The module’s build() is run with every joint at 0 and with the vismach classes replaced by recorders (no OpenGL is needed), and the recorded tree becomes the kinematic tree:

vismach node

Collection

flattened into its parent

Translate, Rotate

a group with the position / orientation (roll, pitch, yaw)

HalTranslate, HalRotate with the key jointN

a translation / rotation axis with joint N

HalTranslate, HalRotate with another key

a HAL-driven axis, the pin from the module’s HAL_PINS

HalShow

a signal node (the pin) with a switch that shows the parts

Box, BoxCentered, BoxCenteredXY

geometry box

CylinderX/Y/Z

geometry cylinder, with two radii a cone

Sphere

geometry sphere (a new shape of the builder)

AsciiSTL

geometry STL, the file is referenced

Color

the colour of the geometry inside

The modules draw in the frame of mchmi’s view (y up), the model’s world has z up: every position, axis and shape is converted. An INI in the module’s directory (#INCLUDE files are followed) gives the joints their letters ([TRAJ]COORDINATES or the kinematics' coordinates=, per channel [CHANNEL_n]JOINTS/COORDINATES), limits, home data, velocity and acceleration; without one the letters follow the axis direction and the limits stay at their defaults. Tools the module draws from the tool file are not imported (the tool slots draw them), so the tool slot of the spindle, magazine nodes and collision groups are added afterwards in the builder. What cannot be converted (Scale, HalRotateEuler, Track, a coordinate read from a HAL pin while drawing, an STL given as data) is listed in the import report; the parts of an unsupported transform are placed without it. The imported model is not saved yet: Speichern suggests <name>.mcm beside the module.

Export of the configuration

Datei > Konfiguration exportieren (or --export DIR) writes into the chosen directory:

  • <name>.ini - [EMCMOT]NUM_CHANNELS, [KINS] trivkins with one letter per joint, [TRAJ]/[CHANNEL_n] with COORDINATES, JOINTS, NAME, MASTER_SPINDLE, TOOL_DB and the TRAORI_k_* data sets of swivel axes (BASE_TOOL = pivot to tool tip at the axis value 0, ROT_DIR in the channel’s machine coordinates), [JOINT_n] with type, limits, velocities and the home keys, [AXIS_x] covering all joints of a letter, [SPINDLE_n], [WORKPIECE_n] (chuck face Z, direction, C joint, slide joint, chuck output), [DISPLAY]MACHINE_MODEL = <name>.mcm. The free keys of the INI page (SECTION.KEY = value) are added, a key given there wins over the derived one.

  • <name>.hal - simulation HAL with the position loopbacks of all joints, one iocontrol per channel and the spindles; <name>_postgui.hal nets the mchmi panel keys and feed pot to every channel’s halui.

  • <name>_chN.tools - an mctooldb tool file per channel listing its stations (written once, never overwritten).

  • <name>.mcm and the STL files it references; linuxcnc_mc.nml for more than one channel.

Export is refused while the model has problems (duplicate joints, gaps in the joint numbers, a letter twice in a channel, min >= max, spindle numbers with gaps).

The model in mchmi

With [DISPLAY]MACHINE_MODEL = <name>.mcm mchmi builds its 3D view from the model: geometry nodes become meshes, axis nodes with a joint follow the joint positions, coupled axes their driver, the tool slots show the tools of the magazines (the station of a turret, the active tool in a spindle place). The collision check takes the static parts (geometry not under a translation joint) as obstacles, parts under one translation joint as moving with it, and the geometry below the joint that carries a channel’s active tool slot as that channel’s holder; the cutter body direction of a milling spindle comes from the slot’s +Z. Hand-written vismach model modules (*_model.py) keep working.