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    Struct Wheel

    Contains wheel settings. For dynamic wheel data refer to WheelOnVehicle.

    Implements
    IComponentData
    IQueryTypeParameter
    Inherited Members
    ValueType.Equals(object)
    ValueType.GetHashCode()
    ValueType.ToString()
    object.Equals(object, object)
    object.GetType()
    object.ReferenceEquals(object, object)
    Namespace: Unity.Vehicles
    Assembly: com.unity.vehicles.dll
    Syntax
    public struct Wheel : IComponentData, IQueryTypeParameter

    Fields

    AddWheelProtectorColliders

    Should the wheel protector collider for this wheel be generated? This collider represents the wheel at full suspension compression, and is used to handle suspension bottoming out and impacts from directions that are not handled by the suspension.

    Declaration
    public bool AddWheelProtectorColliders
    Field Value
    Type Description
    bool

    AntiRollBarStiffness

    Maximum force the anti-roll bar can exert on one side of the suspension, in an attempt to reduce the body roll. Correctly adjusting the center of mass position should be the first step to addressing the body roll.

    Declaration
    public float AntiRollBarStiffness
    Field Value
    Type Description
    float

    FrictionCircleStrength

    Determines how much the longitudinal slip affects the lateral friction. Wheels with value of 1 will have no lateral friction when the wheel is locked or there is wheel spin.

    Declaration
    public float FrictionCircleStrength
    Field Value
    Type Description
    float

    FrictionCurveMaximum

    Peak value of the friction curve. X represents slip and Y represents the grip coefficient. Peak friction happens when there is just enough slip to load the tire, but not enough that it starts sliding. High friction curve stiffness (X lesser than 0.1 or high Y values) should be avoided in case of low physics update rates or when using low number of sub-steps on the Vehicle to prevent the friction from over-correcting and causing jitter.

    Declaration
    public float2 FrictionCurveMaximum
    Field Value
    Type Description
    float2

    FrictionCurveMinimum

    Minimum value of the friction curve, after the peak. X represents slip and Y represents the grip coefficient. This value is relevant when the wheel has enough slip to have already passed the friction peak and is now sliding around. The X value should always be higher than the X value of the FrictionCurveMaximum.

    Declaration
    public float2 FrictionCurveMinimum
    Field Value
    Type Description
    float2

    Mass

    Mass of the wheel, expressed in kg. The mass of the wheel affects only its angular inertia, which determines how long the wheel takes to spin up. Unrealistically small values can cause the simulation to require more sub-steps or result in rotational jitter when the vehicle is stationary.

    Declaration
    public float Mass
    Field Value
    Type Description
    float

    Radius

    Radius of the wheel, expressed in m. Not affected by the scale.

    Declaration
    public float Radius
    Field Value
    Type Description
    float

    SpinEntity

    Entity that will be rotated in order to represent wheel spin.

    Declaration
    public Entity SpinEntity
    Field Value
    Type Description
    Entity

    SuspensionDampingRate

    Combined bump and rebound setting for the suspension damper. Determines how much the suspension will resist changes in suspension length. Higher values will result in a suspension more resistant bouncing and bobbing, but a too high value will reduce the effectiveness of the suspension.

    Declaration
    public float SuspensionDampingRate
    Field Value
    Type Description
    float

    SuspensionMaxLength

    Maximum suspension travel / extension, expressed in m. For best suspension behavior the recommended length is more than the travel expected per one physics update, or the vehicle might bottom out frequently - which is when the suspension runs out of travel and the hard collision through a physics collider takes over. It is usually better to have more travel, and to adjust the vehicle ride height by adusting the suspension position instead.

    Declaration
    public float SuspensionMaxLength
    Field Value
    Type Description
    float

    SuspensionSpringRate

    Spring rate expressed in N/mm. Ideally this value would be set so that at rest, on flat ground, the suspension is about 30% compressed under the vehicle's own weight. Too low value and the vehicle will have less available suspension travel. Too high value and the vehicle will have little suspension travel available in extension, resulting in a wheel that loses contact with the ground easily.

    Declaration
    public float SuspensionSpringRate
    Field Value
    Type Description
    float

    VisualSuspensionSharpness

    Sharpness of the wheel visual movement along the suspension. The higher the value, the less visual smoothing there will be.

    Declaration
    public float VisualSuspensionSharpness
    Field Value
    Type Description
    float

    WheelCollider

    Represents the wheel collider for this wheel. This collider will be used for the wheel collider casts necessary for vehicle physics. It may also be used for the wheel protector collider if the option is enabled.

    Declaration
    public BlobAssetReference<Collider> WheelCollider
    Field Value
    Type Description
    BlobAssetReference<Collider>

    Width

    Width of the wheel, expressed in m.

    Declaration
    public float Width
    Field Value
    Type Description
    float

    Implements

    IComponentData
    IQueryTypeParameter
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