# PhysicsWheelJointDefinition

> A joint definition used to specify properties when creating a PhysicsWheelJoint.

## Definition

* **Type:** Struct
* **Namespace:** [Unity.U2D.Physics](/engine/6000.7/script-reference/unity/u2d/physics.md)
* **Assembly:** UnityEngine.PhysicsCore2DModule
* **Implements:** [IEquatable\<PhysicsWheelJointDefinition>](https://learn.microsoft.com/dotnet/api/system.iequatable-1)

```csharp
public struct PhysicsWheelJointDefinition : IEquatable<PhysicsWheelJointDefinition>
```

## Constructors

| Constructor                                                                                                                                                              | Description                                                                                                              |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------ |
| [PhysicsWheelJointDefinition()](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/ctor.md#physicswheeljointdefinition\(\))                   | Create a default [PhysicsWheelJoint](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljoint.md) definition. |
| [PhysicsWheelJointDefinition(System.Boolean)](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/ctor.md#physicswheeljointdefinition\(bool\)) | Create a default [PhysicsWheelJoint](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljoint.md) definition. |

## Properties

| Property                                                                                                                        | Description                                                                                                                                                                                                                         |
| ------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [autoAnchorA](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/autoanchora.md)                     | When set, [\_localAnchorA](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/localanchora.md) is recomputed from the bodies' current placement at create so both anchor frames coincide in world space. |
| [autoAnchorB](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/autoanchorb.md)                     | When set, [\_localAnchorB](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/localanchorb.md) is recomputed from the bodies' current placement at create so both anchor frames coincide in world space. |
| [autoAxis](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/autoaxis.md)                           | When set, local anchor frame A's rotation is recomputed at create so the slide axis is the direction from anchor A to anchor B.                                                                                                     |
| [bodyA](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/bodya.md)                                 | The first body the joint constrains.                                                                                                                                                                                                |
| [bodyB](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/bodyb.md)                                 | The second body the joint constrains.                                                                                                                                                                                               |
| [collideConnected](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/collideconnected.md)           | Whether the shapes on the pair of bodies can come into contact.                                                                                                                                                                     |
| [drawScale](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/drawscale.md)                         | Controls the scaling of the joint drawing. Not all joints have scalable elements but those that do will use this scaling.                                                                                                           |
| [enableLimit](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/enablelimit.md)                     | Enable/disable the joint translation limit.                                                                                                                                                                                         |
| [enableMotor](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/enablemotor.md)                     | Enable/disable the joint motor.                                                                                                                                                                                                     |
| [enableSpring](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/enablespring.md)                   | Enable/Disable a spring along the joint axis.                                                                                                                                                                                       |
| [forceThreshold](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/forcethreshold.md)               | The force threshold beyond which a joint event will be produced.                                                                                                                                                                    |
| [localAnchorA](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/localanchora.md)                   | The local anchor frame constraint relative to bodyA's origin.                                                                                                                                                                       |
| [localAnchorB](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/localanchorb.md)                   | The local anchor frame constraint relative to bodyB's origin.                                                                                                                                                                       |
| [lowerTranslationLimit](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/lowertranslationlimit.md) | The lower translation limit.                                                                                                                                                                                                        |
| [maxMotorTorque](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/maxmotortorque.md)               | The maximum torque the motor can apply, usually in newton-meters.                                                                                                                                                                   |
| [motorSpeed](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/motorspeed.md)                       | The desired motor speed, usually in degrees per second.                                                                                                                                                                             |
| [springDamping](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/springdamping.md)                 | The spring damping, non-dimensional. Use 1 for critical damping.                                                                                                                                                                    |
| [springFrequency](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/springfrequency.md)             | The spring stiffness frequency, in cycles per second.                                                                                                                                                                               |
| [torqueThreshold](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/torquethreshold.md)             | The torque threshold beyond which a joint event will be produced.                                                                                                                                                                   |
| [tuningDamping](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/tuningdamping.md)                 | Controls the joint stiffness damping, non-dimensional. Use 1 for critical damping.                                                                                                                                                  |
| [tuningFrequency](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/tuningfrequency.md)             | Controls the joint stiffness frequency, in cycles per second.                                                                                                                                                                       |
| [upperTranslationLimit](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/uppertranslationlimit.md) | The upper translation limit.                                                                                                                                                                                                        |
| [worldDrawing](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/worlddrawing.md)                   | Controls whether this joint is automatically drawn when the world is drawn.                                                                                                                                                         |

## Static Properties

| Property                                                                                                                | Description                                                                                                           |
| ----------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------- |
| [defaultDefinition](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljointdefinition/defaultdefinition.md) | Get a default [PhysicsWheelJoint](/engine/6000.7/script-reference/unity/u2d/physics/physicswheeljoint.md) definition. |