> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cyberwave.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Coupled and passive joints

> Which joints you can command directly, and how coupled, passive and fixed joints affect manual input mappings.

In **Control**, map keys, gamepad axes or a leader arm to the robot's independent
joints. A joint can move in the 3D model without being independently commandable.

* **Coupled joints** follow another joint. For example, a gripper can expose one
  finger control while both fingers move together.
* **Passive joints** move with the mechanism but have no independent input.
* **Fixed joints** cannot move and have no joint control.

These choices come from the robot's declared configuration. Missing actuator
information on an older asset does not establish which joints are passive.

## Configure the input

1. Open the asset's **Control** tab, or select the twin in **Workbench → Control**.
2. Select **Joint target control**, then configure an input such as **Keyboard**.
3. Assign a key pair to an independent joint and save. A PiPER gripper with the
   declared finger coupling uses `joint7`; `joint8` is not a second manual target.
4. Review the keys together in **Overview**. Saving a mapping does not start motion.

Twin-specific mappings customize a reusable input without changing its template.
Existing mappings remain available for review; after changing a robot's joint
configuration, review them before use. Model outputs and leader mappings must
also match the independently commandable joints.

## Check the result

Use a supported runtime and compare the commanded target with measured joint
feedback. A correct-looking 3D pose alone does not prove hardware movement.
If a coupled mechanism moves incorrectly, review its declared coupling, joint
limits and driver configuration instead of adding a separate key for the follower.

<CardGroup cols={2}>
  <Card title="Live teleoperation" icon="gamepad" href="/feature-reference/environment-editor/teleoperation">
    Control physical robots through the environment editor
  </Card>

  <Card title="Digital twins overview" icon="clone" href="/feature-reference/digital-twins">
    Capabilities, pairing, and twin concepts
  </Card>
</CardGroup>