Teachers: slips, rolls and the lean back

Four techniques from one take of my motion capture (Muay Thai 02, take_01): the slip uppercut (slip left, lead uppercut), the lean back, and rolling under to the right and to the left. Each has its own input in opponent_evade, and each teacher is warm from the kept student distill4-131.1M, which holds every other skill. An evasion has no target. Its “hit” is the head crossing within 5 cm of the reference’s head at the apex, at any speed.

Round one (evade1): four boxes at once

teacher	gate	verdict
rollR1-238.5M	8/8, 2.5 cm, no falls	failed on video: drops rather than rolls; runs my clip at 1.24× on average
rollL1-226.3M	8/8, 6.3 cm	failed: as rollR1, and its head sweeps the wrong way across
slipup1-204.5M	8/8, ball 8/8	kept for now: “the uppercut still looks good, so keep that one”, “but actually even that one looks like a big uppercut than a slip” (1.42× on average, the uppercut ~0.5 s early)
leanback1-231.8M	0/8, 38.9 cm	failed: never leans; the head drops 7 cm at most

Cause: the punch clock. The policy may play a reference up to twice as fast and is paid for reaching the target sooner. That was made for punches, and only the jab is held to its natural pace. The evasion teachers squeezed my moves, and the gate doesn’t check timing.

Round two (evade2): a wider head path

I asked for the rolls to “roll to the side like a U shape”. The reference was widened (the head 25 cm out), and the head was tracked along its path with a reward.

teacher	gate	verdict
slipup2-196.6M	8/8, 1.9 cm	failed: “looks more like a football headbutt, it just stays there”; the trunk bends sideways 52°
rollL2b-183.5M	8/8, 7.4 cm, the U the right way	failed: trunk side bend 51°, head tilt 59°
rollR2-229.9M	4/8, 10.1 cm	failed: “going sideways but not by bending the torso”; skips the lead-in, ~0.3 s early
leanback2-234.4M	0/8, 19.3 cm	leans now but never reaches the apex

rollL2’s first box ran at 11,000 steps a second against 30,000–34,000 on the others. It was stopped after 0.56 h ($0.38), the machine was added to a skip list, and the run restarted as rollL2b.

Cause: the edited reference. The pelvis couldn’t move the head 25 cm, so the trunk did it with a side bend at its 50° limit, and the teachers learnt the bend. A rebuilt version, with the pelvis moved and the trunk straight, looked physically wrong to me and was never trained. My decision: “Keep to my original reference, like the one from motion capture.”

Where it stands

No roll or lean back is kept. slipup1 stays the slip-uppercut teacher until a better one exists. Its successor, slipup3, goes back to the original capture with the target at the chin (“the target should be where the chin is, not higher than that”); it is not in the ledger yet. Next for the rest: the punch clock held to the capture’s pace for evasions, and a gate that measures timing and shape, not only the crossing.

	machines	machine-hours	cost
evade1 (4 teachers)	4	8.67	$5.56
evade2 (4 teachers, plus rollL2’s slow box)	5	9.06	$5.90
total	9	17.73	$11.46

Every run

From the run records in kakuto-ml: each run's machines, their billed hours and cost (EC2 runs are estimates from the run logs).

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