View component details
WheelColliderNamespace: UnityEngine
Parent class: Collider
Description

A special collider for vehicle wheels.

Wheel collider is used to model vehicle wheels. It simulates a spring and damper suspension setup, and uses a slip based tire friction model to calculate wheel contact forces.

Wheel's collision detection is performed by casting a ray from center downwards the local y-axis. The wheel has a radius and can extend downwards by suspensionDistance amount.

The wheel is controlled with motorTorque, brakeTorque and steerAngle properties.

Wheel collider computes friction separately from the rest of physics engine, using a slip based friction model. This allows for more realistic behaviour, but makes wheel colliders ignore standard PhysicMaterial settings. Simulation of different road materials is done by changing the forwardFriction and sidewaysFriction based on what material the wheel is hitting. See Also: GetGroundHit and WheelFrictionCurve.
Variables
brakeTorque Brake torque. Must be positive.
center The center of the wheel, measured in the object's local space.
forwardFriction Properties of tire friction in the direction the wheel is pointing in.
isGrounded Indicates whether the wheel currently collides with something (Read Only).
mass The mass of the wheel. Must be larger than zero.
motorTorque Motor torque on the wheel axle. Positive or negative depending on direction.
radius The radius of the wheel, measured in local space.
rpm Current wheel axle rotation speed, in rotations per minute (Read Only).
sidewaysFriction Properties of tire friction in the sideways direction.
steerAngle Steering angle in degrees, always around the local y-axis.
suspensionDistance Maximum extension distance of wheel suspension, measured in local space.
suspensionSpring The parameters of wheel's suspension. The suspension attempts to reach a target position.
Functions
GetGroundHit Gets ground collision data for the wheel.
Inherited members
Variables
attachedRigidbody The rigidbody the collider is attached to.
bounds The world space bounding volume of the collider.
enabled Enabled Colliders will collide with other colliders, disabled Colliders won't.
isTrigger Is the collider a trigger?
material The material used by the collider.
sharedMaterial The shared physic material of this collider.
animation The Animation attached to this GameObject (null if there is none attached).
audio The AudioSource attached to this GameObject (null if there is none attached).
camera The Camera attached to this GameObject (null if there is none attached).
collider The Collider attached to this GameObject (null if there is none attached).
collider2D The Collider2D component attached to the object.
constantForce The ConstantForce attached to this GameObject (null if there is none attached).
gameObject The game object this component is attached to. A component is always attached to a game object.
guiText The GUIText attached to this GameObject (null if there is none attached).
guiTexture The GUITexture attached to this GameObject (Read Only). (null if there is none attached).
hingeJoint The HingeJoint attached to this GameObject (null if there is none attached).
light The Light attached to this GameObject (null if there is none attached).
networkView The NetworkView attached to this GameObject (Read Only). (null if there is none attached).
particleEmitter The ParticleEmitter attached to this GameObject (null if there is none attached).
particleSystem The ParticleSystem attached to this GameObject (null if there is none attached).
renderer The Renderer attached to this GameObject (null if there is none attached).
rigidbody The Rigidbody attached to this GameObject (null if there is none attached).
rigidbody2D The Rigidbody2D that is attached to the Component's GameObject.
tag The tag of this game object.
transform The Transform attached to this GameObject (null if there is none attached).
hideFlags Should the object be hidden, saved with the scene or modifiable by the user?
name The name of the object.
Functions
ClosestPointOnBounds The closest point to the bounding box of the attached collider.
Raycast Casts a Ray that ignores all Colliders except this one.
BroadcastMessage Calls the method named methodName on every MonoBehaviour in this game object or any of its children.
CompareTag Is this game object tagged with tag?
GetComponent Returns the component of Type type if the game object has one attached, null if it doesn't.
GetComponentInChildren Returns the component of Type type in the GameObject or any of its children using depth first search.
GetComponents Returns all components of Type type in the GameObject.
GetComponentsInChildren Returns all components of Type type in the GameObject or any of its children.
SendMessage Calls the method named methodName on every MonoBehaviour in this game object.
SendMessageUpwards Calls the method named methodName on every MonoBehaviour in this game object and on every ancestor of the behaviour.
GetInstanceID Returns the instance id of the object.
ToString Returns the name of the game object.
Static Functions
Destroy Removes a gameobject, component or asset.
DestroyImmediate Destroys the object obj immediately. You are strongly recommended to use Destroy instead.
DontDestroyOnLoad Makes the object target not be destroyed automatically when loading a new scene.
FindObjectOfType Returns the first active loaded object of Type type.
FindObjectsOfType Returns a list of all active loaded objects of Type type.
Instantiate Clones the object original and returns the clone.
Operators
bool Does the object exist?
operator != Compares if two objects refer to a different object.
operator == Compares if two objects refer to the same.
Messages
OnCollisionEnter OnCollisionEnter is called when this collider/rigidbody has begun touching another rigidbody/collider.
OnCollisionExit OnCollisionExit is called when this collider/rigidbody has stopped touching another rigidbody/collider.
OnCollisionStay OnCollisionStay is called once per frame for every collider/rigidbody that is touching rigidbody/collider.
OnTriggerEnter OnTriggerEnter is called when the Collider other enters the trigger.
OnTriggerExit OnTriggerExit is called when the Collider other has stopped touching the trigger.
OnTriggerStay OnTriggerStay is called almost all the frames for every Collider other that is touching the trigger.