PhysX Ball Joint component - Lumberyard User Guide

PhysX Ball Joint component

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With the PhysX Ball Joint component, you can create a dynamic ball joint that constrains an entity to the joint with freedom to rotate around the y- and z-axes of the joint.

PhysX Ball Joint component properties


                Properties of the PhysX Ball Joint component
Local Position

Specify the position of the joint relative to the entity transform.

Local Rotation

Specify the rotation of the joint relative to the entity transform.

Lead Entity

Specify the parent entity that will drive the joint.

Breakable

When enabled, the joint will break if sufficient force is applied. Enabling Breakable exposes the Maximum Force and Maximum Torque properties.

Note

PhysX Rigid Body components that have their Compute Mass property enabled might have very large mass values. If the entity containing the joint component or the leader entity have their Compute Mass property enabled, the Maximum Force and Maximum Torque properties might require very high values to resist breaking.

Maximum Force

When Breakable is enabled, specify the maximum force the joint can sustain before breaking. Valid values range from 0.01 to Infinity.

Maximum Torque

When Breakable is enabled, specify the maximum torque the joint can sustain before breaking. Valid values range from 0.01 to Infinity.

Display Setup in Viewport

When enabled, a cone that represents the orientation and limits of the ball joint and a line that represents the connection between the joint and its leader are displayed. The shape of the cone is defined by the Y axis angular limit and the Z axis angular limit.

Select Lead on Snap

When enabled, snapping the joint to an entity in component mode will set the entity as the Lead Entity. The entity containing the joint component is excluded from this operation.

Lead-Follower Collide

When enabled, the lead entity and follower entity (the entity containing the joint component) will collide.

Limit

When enabled, the lead entity's movement around the joint axes is constrained by angular limits. Enabling Limit exposes the Soft Limit, the Y axis angular limit, and the Z axis angular limit properties.

Soft Limit

When enabled, the lead entity's movement around the joint axes is allowed to pass the specified limit. With Soft Limit enabled, when the lead entity rotates past the limit, the lead entity's movement is treated as a spring and will slow, then spring back to the limit area. Enabling Soft Limit exposes the Damping and Stiffness properties.

Damping

When Soft Limit is enabled, the spring's drive relative to the velocity of the follower when outside the rotation limit. Valid values range from 0.001 to 1000000.0.

Stiffness

When Soft Limit is enabled, the spring's drive relative to the position of the follower when outside the rotation limit. Valid values range from 0.001 to 1000000.0.

Y axis angular limit

The rotation limit around the joint's y-axis when Limit is enabled. Valid values range from 0.1 to 180.0.

Z axis angular limit

The rotation limit around the joint's z-axis when Limit is enabled. Valid values range from 0.1 to 180.0.

Edit

When clicked, component edit mode is enabled. In component edit mode, all components are locked except for the PhysX Ball Joint component. The properties of the PhysX Ball Joint component can be edited in Perspective. Press Tab to cycle through the component edit modes. Click Done to exit component mode.