Physics Joints

Dynamic joints can be used to simulate complex mechanisms. Joints specify how two rigid bodies can move relative to each other. Some joints can also be driven by motors using positional or velocity control, which incorporate a feedback loop.

Types

There are five types of joint supported.

Prismatic (Slider)

Constrains the rigid body such that it is only permitted to slide along a single axis relative to the base. The joint’s position can be driven by a motor.

Revolute (Hinge)

Constrains the rigid body such that it is only permitted to rotate in a plane about a point relative to the base. The axis specifies the normal for the plane. The anchor specifies the point about which the body is permitted to rotate. The joint’s angle can be driven by a motor.

Distance (*)

Constrains the rigid body such that the distance between the point on the body and the point on the base are within a specified range.

Gear (*)

Constrains the rigid body such that its rotation and angular velocity maintains a specified ratio relative to the base.

Rack and Pinion (*)

Constrains the rigid body such that its position and linear velocity maintains a specified ratio relative to the base’s rotation and angular velocity.

Path (*)

Constrains the rigid body such that it is only permitted to move along a path relative to the base. The anchor specifies the point which is projected onto the path and moves along the curve. The joint’s position can be driven by a motor.

Spherical (Ball & Socket)

Constrains the rigid body such that it is only permitted to rotate about a specified point relative to the base.

Fixed (Locked)

Constrains the rigid body such that it is locked/fixed relative to the base.

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(*) Coming Soon