Leg rig: safety

Read this before the first power-up. Go through the checklist before every session. The tests are in docs/leg-bench-tests.md and the wiring in docs/leg-rig-wiring.md.

What can hurt

The leg. Two motors of up to 120 N m each (the firmware caps them at 60 N m). The five-bar's links scissor at the knees and between the upper links and the hip frame. A jump extends the leg 190 mm in under 0.2 s. Keep fingers out of the linkage whenever the pack is connected.
The carriage. About 15 kg on the rails. A power cut drops it onto the bumpers (7 J). A hard fault at the jump's apex is up to 33 J. The ballast plates are cast iron.
The pack.
- Two DeWalt FLEXVOLTs in 20 V mode in series (D65): 30-41 V, with no cut-off of their own. They deliver 50-60 A in a jump.
- The contactor stays closed for 1.0 s after the pendant is let go.
- The bench supply cannot absorb the motors' regeneration: never run a squat, jump or drop on it.
The drop test. The quick-release pin and the carriage under it.

The rules

One operator holds the pendant. Nothing moves unless it is held and the runner has been armed (typing ARM). Let go at any doubt. The leg sits down in 0.3 s, and 1.0 s later the contactor opens whatever the software did.
The clear zone. Nobody within 1.5 m of the leg's front and sides while the pack is connected, the operator included. Tape it on the floor. Wear eye protection inside the room.
The pack is the master switch. Unplug its XT60 before touching the leg, its wiring or the pod. Wait 5 s after unplugging: the motors' capacitors discharge.
The bench supply is only for the bench tests. Use it for B1, B2 and C1-C6, never with the leg on the rig.
Jumps and drops start at or under the start voltage: 44.5 V - 40 A x the packs' resistance (B6), about 40.5 V until B6 has run (a pair fresh off the charger is 41 V: one stand-up brings it under). The runner refuses above it.
The power-cut tests (S5, S6) cut the power by the pendant. Hold it, let go, and the leg falls. S6 (onto the leg's own stops) only after B1 and the main session's rerun clear it.
A pack that is damaged, swollen or hot goes outside onto concrete. Keep an ABC extinguisher by the door.

The checklist (each session)

#	Check	How	OK when
1	The pendant and relay	Motors' XT60 unplugged at the pod. Hold the pendant, then let go	The contactor clicks in when held and opens 1.0 s (stopwatch) after release; the runner shows the node's RUN while held
2	The CAN bus	Power off: an ohmmeter across H and L at the junction	60 ohm
3	The motors	`python -m rig.rs04 --iface can0 scan`	both ids (1, 2) answer; the start-up log shows limit_torque 60, canTimeout 2000 and damper 0
4	The calibration	`python -m rig.calibrate --check` with the carriage on its bumpers	the leg's length within 5 mm of a tape measure
5	The packs	A multimeter at the pod's inlet	33-41 V for stand and squat; at or under the start voltage for a jump or a drop
6	The tethers	Look	the carriage tether through the plate's tether hole on a locked screwgate, 150 mm slack above the highest jump; the link tether round the wheel link
7	The bumpers	A rule from the deck to the plate's edge, carriage resting	contact at a leg length of 140 mm (the base and cap seated); S6 only: 74 mm with its shims
8	The top stop	Look	at its mark above the rails (B5 lowers it onto the carriage: put it back after)
9	The ballast	Look and torque	the plates retained by the 2 in washer and the 3/8-16 screw at 25 N m
10	The screws	The paint marks	unbroken on the plate-to-frame M5s, the link screws, the knee nuts and the stop posts
11	The motors' temperature	The last run's log, or `python -m rig.rs04 --id N watch`	under 40 C before a jump or a drop; under 60 C for anything
12	The zone	Look	taped, empty, eye protection on; the laptop on battery (or the isolated USB-CAN if it is on mains)

If something goes wrong

The leg does something unexpected: let go of the pendant. Do not reach for the leg.
A motor faults or the runner aborts: the run's log says why. Read it before the next run. Clear a fault with python -m rig.rs04 --id N clear only once the cause is understood.
The contactor does not open on release: unplug the pack's XT60. Do not run again until check 1 passes.
A part cracks or a screw backs out: stop the series. Photograph it, write it down in exports/rig/runs/notes.md and tell the main session before any repair.