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

# gravity-comp

> Hold both arms in gravity-compensation mode so you can move them by hand.

Holds both arms in gravity-compensation mode so you can move them by hand. Each *free* arm joint is sent `set_impedance` with `kp=0`, `kd=KD`, and a feedforward torque equal to the URDF-modelled gravity. Joints not in the free set are held rigidly at their current position with their configured `ArmConfig` `kp`/`kd` (still gravity-compensated). The grippers are softly held at their current positions.

This command is configured via draccus — see [Command configuration](/cli/configuration).

| Flag                                                       | Description                                                                                                                                              |
| ---------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `--left_channel <ch\|null>` / `--right_channel <ch\|null>` | CAN channel per arm; `null` disables that arm.                                                                                                           |
| `--free_joints [J1,J2,...]`                                | List of joints to gravity-compensate (e.g. `[WRIST_3]` or `[SHOULDER_1,ELBOW]`). Other arm joints are held in place. Default `null` = all 7 joints free. |
| `--kd FLOAT`                                               | Velocity damping coefficient on *free* joints (Nm·s/rad). Higher = less floppy. Default 0.25                                                             |
| `--rate_hz FLOAT`                                          | Control loop rate in Hz (default: 250)                                                                                                                   |
| `--telemetry_hz FLOAT`                                     | Joint telemetry poll rate in Hz (default: 500)                                                                                                           |
| `--log_level {DEBUG,INFO,WARNING,ERROR}`                   | Default: `INFO`                                                                                                                                          |
| `--config_path PATH`                                       | Load a whole-config JSON/YAML file; CLI overrides layer on top.                                                                                          |

```bash theme={null}
axol gravity-comp                                 # all 7 joints free, both arms
axol gravity-comp --right_channel null            # left arm only, all joints free
axol gravity-comp --kd 1.0                        # heavier damping
axol gravity-comp --free_joints [WRIST_3]         # only WRIST_3 free; everything else held rigid
axol gravity-comp --right_channel null --free_joints [SHOULDER_1,WRIST_3]   # one-arm, two-joint isolation
```

Use `--free_joints` to test gravity comp on a single joint at a time: only the named joints float freely, while the rest of the arm holds its pose so you can isolate the effect.

<Tip>
  If the arm sags or pushes back, tune the per-joint `mass` and `com` fields on `AxolConfig` (each `JointConfig` carries the inertial of the URDF body it drives) — see [Gravity compensation](/api/robot#gravity-compensation).
</Tip>