Rolling wheel

Converts rotation to translation without slip: v = r·ω.

  • rotational
  • translational
  • Modelica Standard Library
  • 2 ports
  • 1 parameter
BlockRolling wheelKindrollingWheelLibraryRotational

Description

An ideal wheel that rolls without slip: it converts the rotation of the axle into translation of the contact point. Use it to connect a rotational drivetrain to a vehicle mass.

Example

Wheel and rack A wheel turns axle torque into force on a vehicle mass, and a rack and pinion turns speed into travel.

30 N·mWheel 0.1 kg·m²Wheel r 0.3 mVehicle 100 kgDrag 10 N·s/mRoadVehicle speedPinion 10 rad/sRack and pinionRack 1 kgRack position
In Gradara, select a Rolling wheel block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:Inertia (ideal)Rack and pinionConstant torqueConstant speedFixed (translational)MassDamperPosition sensorVelocity sensor

Ports

Conserving terminals 2

  • rotflangeRrotational

    Rotational flange (the axle). Torque into it is positive.

  • linflangeTtranslational

    Translational flange (the road contact). Force into it is positive.

Parameters

  • Radiusradius0.3 m

    ≥ 0

    Wheel radius, in meters. Must be positive.

Equations

Modelica
flangeT.s = radius · flangeR.phi
0 = radius · flangeT.f + flangeR.tau

Implementation

Modelica Standard Library 4.1.0Modelica.Mechanics.Rotational.Components.IdealRollingWheel
MSL documentation

Assumptions and limitations

  • No wheel inertia, rolling resistance, or tire slip. Add Inertia (ideal) on the axle for the wheel’s own inertia.

Used in

These larger examples use it too. Open them from Examples in the app.

  • EV drivetrain

See also

Select a block in Gradara and press F1 to open its page offline.