2021.1.1208.2 Double Wheel Joint

1 Overview
2 Where to find
3 Feature layout
4 How to use
5 How to use limits

Overview

This kinematic relation is used to define a rotational constraint on an object.

Where to find

The Kinematic Wheel Joint can be found under Mechanics > Kinematics > Kinematic Joints > Add Wheel Joint.

This will add the Kinematic Wheel Joint component to the currently selected object or create a new empty GameObject with the component attached if no objects are selected.

Joints must be placed as children of a Body Controller in the hierarchy.

The following inspector will be shown:

Feature layout

The image below shows the complete feature layout of the Kinematic Wheel Joint component.

Generic Joint Settings
Pass Priority	Priority of the kinematic chain calculations. Higher numbers are calculated earlier.
Enforce Outside Playmode	Enforces the joint to work in edit mode.
Prevent Kinematic Update	Removes the joint from the kinematic chain calculations.
Min Translation Delta	The minimum value the joint detects as a change in position.
Min Rotation Delta	The minimum value the joint detects as a change in rotation.
Kinematic Chaining
Show in Scene View	Shows chained connections of this object through arrows.
Show When Not Selected	Shows chained connections of this object through arrows even when the object is not selected.
Add Kinematic Transfer Relation	When a kinematic Body is dragged into this a transfer relation between them is created.
Opposing Kinematic Relation	The Kinematic Body which this relation is connected.
Relation Direction	Describes the direction of the manipulation of the Transforms. The following options are available: BIDIRECTIONAL: Allows for both kinematic transforms, when they are being manipulated, to manipulate each other equally. RECIEVE_ONLY: Allows for the joint, when it is being manipulated, to manipulate the opposing kinematic transform, but not the other way around. SEND_ONLY: Allows for the opposing kinematic transform, when it is being manipulated, to manipulate the joint, but not the other way around.
Ratio	The ratio in which the relation is done (1 means all the applied rotation translation is equally transferred).
Invert Relation	If the relation is in inverted direction (so if rotating to right the connected object rotates to the left).
Wheel Joint Settings
Notation	The angle notation for the Wheel Joint inspector. The following options are available: DEGREES: Displays the limits and current rotation in degrees. REVOLUTIONS: Displays the limits and current rotation in number of revolutions. RADIANS: Displays the and current rotation limits in radians.
Wheel Radius	The Radius of the Wheel Joint.
Use Wheel Radius Gizmo	When checked a handle in the Scene view is added and can be manipulated manually to set the Wheel Radius.
Limit Rotation	When checked, settings appear to set the minimum and maximum rotation of the Wheel Joint.
Minimum Rotation	The minimum rotation limit of the Wheel Joint.
Use Min Rotation Gizmo	When checked, a handle in the Scene view is added and can be manipulated manually to set the Minimum Rotation Limit.
Maximum Rotation	The maximum rotation limit of the Wheel Joint.
Use Max Rotation Gizmo	When checked, a handle in the Scene view is added and can be manipulated manually to set the Maximum Rotation Limit.
Wheel Axis Direction	A Scene Vector describing the axis of the Wheel Joint.
Wheel Forward Direction	A Scene Vector describing the forward direction of the Wheel Joint.
Sceneview Settings
Always Enabled	When checked all gizmo’s and handles of the Wheel Joint are shown in the scene view even when the object is not selected.
Enable in Scene View
Color Settings
Wheel Plane	The color of the Wheel Radius.
Axis Direction	The color for the Wheel Axis Direction.
Forward Direction	The color for the Wheel Forward Direction.
Current Rotation	The color for the Current Rotation State.
Rotation Limit	The color for the Minimum Rotation Limit and Maximum rotation limit.

How to use

Add a Kinematic Wheel joint to an object.
Set the Wheel Axis Direction to the desired direction.

3. Set the Wheel Radius to the desired radius.

4. Create a new Transform Relation, add an Opposing Relation Instance and define the other settings as needed.

5. Test if the Transform Relations are working.

To test your Transform Relations outside of playmode make sure Enforce Outside Playmode is checked on both Joints.

How to use limits

Click the Limit Rotation checkbox.

2. Use the Minimum Rotation Limit and Maximum rotation limit fields or use the scene gizmo’s to set the limits.

3. Test if the limits work by manipulating both Joints.