tune.friction

Identifies the four friction-model parameters for one joint via a bidirectional velocity sweep. Gravity is computed centrally from the URDF (see Gravity compensation), so this command only fits the friction half-difference and a constant offset. Friction model: τ = Fc·tanh(0.1·k·v) + Fv·v + Fo

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 (default: from `AxolConfig`)
`--kd FLOAT`	Derivative gain (default: from `AxolConfig`)
`--velocities V [V ...]`	Velocity setpoints in rad/s (default: ~0.1, 0.3, 0.6, 0.9, 1.3)
`--lo RAD`	Override lower joint limit for the sweep
`--hi RAD`	Override upper joint limit for the sweep
`--dump-csv [PATH]`	Write per-bin `(v, q, tau_fwd, tau_bwd, tau_avg, tau_halfdiff)` rows to a CSV for offline plotting / arm-vs-arm comparison. Pass without a value to auto-name as `logs/friction_<side>_<joint>_<timestamp>.csv`

axol tune.friction --l --joint shoulder_1 --kp 30 --kd 0.8
axol tune.friction --r --joint elbow --kp 20 --kd 0.6
axol tune.friction --l --joint wrist_1 --velocities 0.2 0.6 1.0
axol tune.friction --l --joint shoulder_2 --dump-csv

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