> ## 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.

# tune.pid

> Tune Kp/Kd gains for a single joint via sinusoidal or step-response tracking.

Tunes `Kp`/`Kd` gains for a single joint at \~100 Hz using sinusoidal tracking or step-response, and prints error statistics.

| Flag                 | Description                                                                                   |
| -------------------- | --------------------------------------------------------------------------------------------- |
| `--l` / `--r`        | Arm side (required)                                                                           |
| `--joint JOINT`      | `shoulder_1`, `shoulder_2`, `shoulder_3`, `elbow`, `wrist_1`, `wrist_2`, `wrist_3` (required) |
| `--kp FLOAT`         | Proportional gain (required)                                                                  |
| `--kd FLOAT`         | Derivative gain (required)                                                                    |
| `--tff`              | Apply full feedforward (gravity + friction)                                                   |
| `--mode {sine,step}` | `sine` = sinusoidal tracking (default); `step` = step response                                |
| `--amp FLOAT`        | Motion amplitude in rad (default: auto safe value)                                            |
| `--freq FLOAT`       | \[sine] Frequency in Hz (default: 1.0)                                                        |
| `--duration FLOAT`   | \[sine] Duration in seconds (default: 5.0)                                                    |
| `--hold FLOAT`       | \[step] Hold time per phase in seconds (default: 2.0)                                         |
| `--rate FLOAT`       | Command rate in Hz (default: 100.0)                                                           |

```bash theme={null}
axol tune.pid --l --joint elbow --kp 25 --kd 0.6
axol tune.pid --r --joint shoulder_1 --kp 35 --kd 1.2 --mode step
```