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Calibrates the telescoping lift by running the lift controller’s two-ended homing sequence: the legs drive up until they reach the top stop, then down to the bottom stop. On success the controller rebases its position counters (bottom = 0), sets soft limits a margin inside the hard stops, and saves everything to its flash — establishing the height scale that lift.goto and the teleop height display use.
There are two modes:
  • Together (default) — for legs bolted to the robot, with or without the robot on top. The legs move as one, and the first leg to reach a stop stops both, so the frame is never racked. Whatever height offset the legs start with is kept.
  • Independent (--independent, or the Independent toggle in the dashboard dialog) — for loose legs off the robot, e.g. before mounting or after swapping a leg. Each leg runs to its own top and bottom stops and is zeroed at its own bottom, so legs that start at different heights end up level.
Never home independently with the legs mounted: after the first leg reaches its stop, the other keeps pushing alone against the frame until its own stall cut fires.
Lift firmware before v0.9 ignores the mode and always homes each leg independently. The sequence takes 1–2 minutes and intentionally touches both end stops. Progress streams as status lines; Ctrl-C (or Stop in the control panel) aborts safely — an interrupted homing rolls back to the previous calibration, so the lift is never left half-homed.
Homing normally happens once ever, not per boot: the legs are self-locking (they cannot move unpowered), so the saved position stays valid across power cycles. Re-home only if the columns were turned by hand or the controller died mid-move.
Requires the lift’s CAN bus (named by can.setup) and a powered lift board. By default the command uses the chest bus can_alm_axol_c when that interface exists, otherwise the wheel bus can_alm_axol_b the lift shares with the motors; pass --channel to use a different interface. Also available from the control panel’s diagnostics dashboard under Diagnostics → Home the lift.