Unity Script Reference – WheelCollider

WheelCollider Inherits from Collider

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

center	The center of the wheel, measured in the object's local space.
radius	The radius of the wheel, measured in local space.
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
mass	The mass of the wheel. Must be larger than zero.
forwardFriction	Properties of tire friction in the direction the wheel is pointing in.
sidewaysFriction	Properties of tire friction in the sideways direction.
motorTorque	Motor torque on the wheel axle. Positive or negative depending on direction.
brakeTorque	Brake torque. Must be positive.
steerAngle	Steering angle in degrees, always around the local y-axis.
isGrounded	Indicates whether the wheel currently collides with something (Read Only).
rpm	Current wheel axle rotation speed, in rotations per minute (Read Only).

Functions

GetGroundHit

Gets ground collision data for the wheel.

Inherited members

Inherited Variables

enabled	Enabled Colliders will collide with other colliders, disabled Colliders won't.
attachedRigidbody	The rigidbody the collider is attached to.
isTrigger	Is the collider a trigger?
material	The material used by the collider.
sharedMaterial	The shared physic material of this collider.
bounds	The world space bounding volume of the collider.
transform	The Transform attached to this GameObject (null if there is none attached).
rigidbody	The Rigidbody attached to this GameObject (null if there is none attached).
camera	The Camera attached to this GameObject (null if there is none attached).
light	The Light attached to this GameObject (null if there is none attached).
animation	The Animation attached to this GameObject (null if there is none attached).
constantForce	The ConstantForce attached to this GameObject (null if there is none attached).
renderer	The Renderer attached to this GameObject (null if there is none attached).
audio	The AudioSource attached to this GameObject (null if there is none attached).
guiText	The GUIText 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)
guiTexture	The GUITexture attached to this GameObject (Read Only). (null if there is none attached)
collider	The Collider attached to this GameObject (null if there is none attached).
hingeJoint	The HingeJoint attached to this GameObject (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).
gameObject	The game object this component is attached to. A component is always attached to a game object.
tag	The tag of this game object.
name	The name of the object.
hideFlags	Should the object be hidden, saved with the scene or modifiable by the user?

Inherited Functions

ClosestPointOnBounds	The closest point to the bounding box of the attached collider.
Raycast	Casts a Ray that ignores all Colliders except this one.
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.
GetComponentsInChildren	Returns all components of Type type in the GameObject or any of its children.
GetComponents	Returns all components of Type type in the GameObject.
CompareTag	Is this game object tagged tag?
SendMessageUpwards	Calls the method named methodName on every MonoBehaviour in this game object and on every ancestor of the behaviour
SendMessage	Calls the method named methodName on every MonoBehaviour in this game object.
BroadcastMessage	Calls the method named methodName on every MonoBehaviour in this game object or any of its children.
GetInstanceID	Returns the instance id of the object.
ToString	Returns the name of the game object.

Inherited Messages Sent

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.
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.

Inherited Class Functions

operator bool	Does the object exist?
Instantiate	Clones the object original and returns the clone.
Destroy	Removes a gameobject, component or asset.
DestroyImmediate	Destroys the object obj immediately. It is strongly recommended to use Destroy instead.
FindObjectsOfType	Returns a list of all active loaded objects of Type type.
FindObjectOfType	Returns the first active loaded object of Type type.
operator ==	Compares if two objects refer to the same
operator !=	Compares if two objects refer to a different object
DontDestroyOnLoad	Makes the object target not be destroyed automatically when loading a new scene.