control mode: REPRODUCE the "centering fought my control" fight, and prove the fix in Sauron's config

Follow-up to 4ccc2a7, which fixed the mechanism but could not reproduce the
field symptom.  His fuller wording -- the centering "FOUGHT" his control, not
"the torso died" -- is what cracked it.

WHY "FOUGHT" IS THE PRECISE SYMPTOM.  TorsoSimulation's frame order is
  1. digital twist commands   -> currentTwist += d;  recenterActive = 0
  2. centerCommand > 0        -> recenterActive = 1        (re-armed)
  3. analog twist axis != 0   -> currentTwist += d;  recenterActive = 0
  4. if (recenterActive)      -> Recenter(dt)              (drags toward 0)
Desktop/glass torso input is ANALOG (Q/E -> gBTTwistAxis -> stickPosition.x), so
with centerCommand stuck the torso HOLDS while you are actively pushing (step 3
clears the arm) and snaps back the instant you ease off (step 2's arm survives
into step 4).  You can only hold it off-centre by pushing continuously.  That is
"the centering fought my control", exactly.

WHY IT ONLY BITES THE GLASS/POD BUILD -- and why the first bench came back clean.
The ONLY caller of ClearRecenterCommand() sits INSIDE the desktop key-bridge
block, gated on `gBTDrive.forced || !BTRIODevicePresent()`.  With a RIO present
-- and on glass builds PadRIO IS the rioPointer -- the bridge is OFF and NOTHING
ever clears centerCommand, so one pass through Basic pins it at 1 for good.  A
plain desktop build clears it every frame and self-recovers.
The first modecycle.sh run needed BT_KEY_BRIDGE=1 to make the mode-cycle hook
run at all -- and that same flag switched on the only thing that clears the cell,
masking the bug under test.  The hook is now deliberately OUTSIDE that block so
the bench can run the RIO-present configuration.

MEASURED A/B, bridge OFF (Sauron's config), BT_TWIST_PULSE deflect/release:

                          LEGACY                      FIXED
  ctrCmd=1 samples        310  (latched for good)     0
  twist during RELEASE    decays 0.443->0,            HOLDS 2.44346
                          0.900->0.436  (recen=1)
  recen=1 samples         permanently armed           14 (one-shot per Basic
                                                      entry, then self-clears)

So the authentic one-shot re-centre still happens on entering Basic; it just
settles instead of fighting the pilot forever.

New bench hook BT_TWIST_PULSE=<n>: deflect the analog twist axis for n ticks
then RELEASE for n ticks, repeating.  BT_LOCK_SWEEP never releases, so it cannot
show this symptom at all -- the release window IS the measurement.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018SgmXGNMXavXiafKXf9MDC

This commit is contained in:

Joe DiPrima

2026-08-08 13:59:39 -05:00

co-authored by

Claude Opus 5

parent 4ccc2a7eec

commit 9657fbb11e

3 changed files with 48 additions and 18 deletions

									
										scratchpad/night13/modecycle.sh
									
		+1
		-1
	
												View File
												
				@@ -40,7 +40,7 @@ bt_expert_egg MP.EGG MC.EGG

				sed -i "s/^map=.*/map=grass/; s/^time=.*/time=day/; s/^vehicle=.*/vehicle=madcat/" MC.EGG

				( export BT_MODECYCLE_EVERY=400

				  export BT_TORSO_LOG=1 BT_KEY_NOFOCUS=1 BT_KEY_BRIDGE=1 ${LEGACY:+BT_LEGACY_MODE_RECENTER=1}

				  export BT_TORSO_LOG=1 BT_KEY_NOFOCUS=1 BT_KEY_BRIDGE=0 BT_TWIST_PULSE=150 ${LEGACY:+BT_LEGACY_MODE_RECENTER=1}

				  bt_launch mc_a.log MC.EGG 0x03 )

				sleep 150

				bt_kill_ours; sleep 2; taskkill //F //IM btl4.exe > /dev/null 2>&1; sleep 3