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A six-axis robot arm in green, seen from below, its flange toward the viewer: Buerligons in its realistic look

buerligons.io · the app

Buerligons is a parametric, history-based CAD modeler that runs entirely self-contained on the ClassCAD WebAssembly. Nothing to install, no server doing the modeling.

Robot6Axis_FC.ofb · Buerligons, realistic look

01Sketch

Everything starts with a sketch, which you can constrain and dimension. Expressions can contain formulas or other expressions. A part made of it will follow when these change.

1Step Width in the expressions
2Point at a constraint: it shows what it holds

Part · Bracket · Profile

sketch.createProfile

Geometry

Constraints

Dimensions

Expressions✓ solved

Recorded from ClassCAD: every width is the solver's own answer. Open Bracket.ofb in the editor ↗

02Assemble

Assemblies place and constrain parts and sub-assemblies with 3D constraints. A revolute constraint with a gear relation can move parts as they would in the real world.

1Turn the drivetrain in its window
2Point at a part, or at a row in the structure

ClassCAD · WebAssembly · this tab · readyTurn the drivetrain: every gear and roller follows. Drag the shooter: it turns.Constraints27Instances165Modeassembly

FRC team 1678's 2024 shooter pivot, rebuilt in ClassCAD from scratch: every part native, with its sketches and features; 27 constraints that let it move, gears and all.Open it in the editor ↗

03Patterns

A feature takes numbers or expressions. Here the holes of a foam insert are a linear pattern: its rows and columns are two expressions, the spacing between the holes is a formula of them, so the holes stay centred always.

1Step Rows and Columns in the expressions
2Watch the spacing: it is a formula

part.linearPatternLinear pattern
Count 1@expr.Columns
Distance 1@expr.yDistmm
Count 2@expr.Rows
Distance 2@expr.zDistmm

Expressions

Rows
4
Columns
8
zDistToFirst
= 0
yDistToFirst
= 0
zDist
= 0
yDist
= 0
Holes
32
Volume
— cm³

Shadowbox.ofb, rebuilt in ClassCAD for every pair of counts. Open it in the editor ↗

04Tools

Buerligons covers most of the features that the underlying kernels provide, SMLib for 3D and LGS for constraints.

71 tools · 4 sheets
Read the docs →

  • Sketchsketch.create
  • Extrusionpart.extrusion
  • Revolvepart.revolve
  • Twistpart.twist
  • Boxpart.box
  • Cylinderpart.cylinder
  • Conepart.cone
  • Spherepart.sphere
  • Unionpart.boolean
  • Subtractionpart.boolean
  • Intersectionpart.boolean
  • Filletpart.fillet
  • Chamferpart.chamfer
  • Slicepart.slice
  • Slice by sheetpart.sliceBySheet
  • Mirrorpart.mirror
  • Linear patternpart.linearPattern
  • Circular patternpart.circularPattern
  • Translationpart.translation
  • Rotationpart.rotation
  • Transform by csyspart.transformationByCSys
  • Work planepart.workPlane
  • Work axispart.workAxis
  • Work pointpart.workPoint
  • Work coordinate systempart.workCSys
  • Expressionspart.expression

05Showcases

Try them, see how they're made.

Assembly · FRC team 1678

History-based, at full size

Shooter pivot

Team 1678's 2024 shooter, rebuilt in ClassCAD from scratch: every part native, with its sketches and features; 27 constraints that let it move, gears and all.

Instances
165
Parts
75
Constraints
27
File
61.8 MB
Download
5.3 MB
Open it in the editor ↗

ClassCAD needs about a gigabyte to open it: it opens best on a computer.

  • Part

    Radial displacement

    Schmidt coupling

    Links and discs on revolutes: a coupling that takes up a radial offset between two shafts.

    Open it in the editor ↗
  • Part

    Constraint limits

    Cutting tool

    A tool in its holder on a slider: the constraint’s limits say how far it goes.

    Open it in the editor ↗
  • Part

    Feature-based design

    Shaft

    Sketches, extrusions, a mirror, booleans and a fillet: a part that is its history.

    Open it in the editor ↗
  • Part

    Parametric design

    Flange

    Its sizes are formulas of thickness and diameter; its bolt holes a circular pattern, cut in one go.

    Open it in the editor ↗
  • Part

    Dimensions with names

    Bracket

    One fully constrained sketch, its dimensions bound to Width, Height and Hole, extruded.

    Open it in the editor ↗
  • Part

    Patterns from expressions

    Shadowbox

    A foam insert whose holes are a linear pattern of Rows × Columns, centred by formula.

    Open it in the editor ↗
  • Part

    An assembly of parts

    Fusion

    Three parts placed as five instances, opened as one assembly.

    Open it in the editor ↗

8 models · 66.1 MB of OFB · 5.9 MB to download, all of them

06Files

Buerligons covers many common import and export formats, first and foremost STEP. OFB is our parametric history format that retains all sketches, features, expressions and so on.

Not yet

2D drawings, sweeps, SAT and IGES. Phones get a viewer, not the editor.

07Start

01

A new part

An empty part, the sketcher and every feature, in a new tab.

02

An assembly

Bring parts in, constrain them, and move them.

03

Your own file

An .ofb, a STEP or an IWP from your disk, opened right in the browser.

Read the docsSketchingExpressions3D constraintsCommercial use