Transmission

The transmission component defines a linear gearing relationship between two physics joints. For more details on all properties associated with the transmission component and how to use the transmission component with scripting, please see the API documentation.

Description

All combinations of the following types of joints are supported:

Prismatic
Revolute
Path

The transmission component can relate (gear) the position (distance/angle) of one joint to another joint through a given ratio. The position of the output joint is constrained to be equal to the position of the input joint multiplied by the ratio:

$$\text{output}=\text{input}\cdot\text{ratio}$$

This constraint is efficiently solved by the physics engine as part of the overall system of constraint equations. Unlike other physics simulators, which constrain only the velocities, the transmission component ensures that the positions of the joints do not drift apart over time. It is typically used for modeling:

Spur Gears
Helical Gears
Bevel Gears
Miter Gears
Worm Gears
Screw Gears
Rack and Pinions
Chain Drives

You can also use the transmission component to chain parts that move along a track. You can simulate this by adding a path joint to every part along the track, then add a transmission component between each pair of parts with the position ratio set to one. This will allow you to drive the entire transport system with a single motor. All the other parts will move as the motor moves the first part due to the position constraint enforced by the transmission component.

Properties

The transmission component properties that are accessible through the inspector.

Input

The input joint.

Output

The output joint.

Ratio

The desired ratio that relates the input joint position to the output joint position. It must be non-zero. The ratio can be negated to flip the direction of the output joint relative to the direction of the input joint.