07 Self-righting usage and monitoring

Every finished unit is tested in all four directions before shipping. For the first use, still verify each direction once per section 7.2 to make sure the unit is healthy after transport.

7.1 Procedure

1. Power up with the robot upright and wait for autorun on: get-up waits for a fall;
2. Knock the robot over in any direction, release it and keep it still for about 0.5 s;
3. When getup start pose=<pose> appears, the executor starts automatically;
4. On success the firmware prints standing -> executor done and returns to standby;
5. If a run exceeds 14 s the firmware prints executor timeout; after a 1.5 s cooldown the fall gate re-triggers and retries.

7.2 Expected behavior per direction

Pose	Mechanism	Real-robot time
pitch_neg (top → −X)	Elbow plants, shoulder stroke levers the body up	~3 s
pitch_pos (top → +X)	Same lift; if it tips over during retract, the pose re-plan runs pitch_pos again	~5–6 s
roll_pos (top → −Y)	Direct shoulder lever using the long travel side	~3 s
roll_neg (top → +Y)	Full-travel direct press → elbow-wedge pumps ×2 → whip-slam retry if needed; no roll-over	~2–6 s

Earlier firmware rolled roll_neg over the top and re-planned to a pitch lift (5–14 s); the current build uses the mirror of the +Y press, so all four directions are symmetric and comparable in speed. An occasional executor re-plan roll_neg -> ... just means that press failed and the fallback retry kicked in - that is the normal safety net.

7.3 Executor logic (in firmware)

• 20 ticks (0.4 s) per reference waypoint, linear interpolation; output slew limit 0.08 rad/tick;
• After the waypoints, retract the arm to neutral at 0.033 rad/tick;
• Done when up_z > 0.95 with the target at zero for 50 ticks;
• If the body settles on another lying axis (up_z<0.6, |ω|<0.8 for 15 ticks), retract to neutral and switch to the new pose's reference (up to 5 switches);
• The roll_neg reference uses per-stage adaptive holds: press/pump stages hold while up_z<0.92 up to a per-stage tick cap (press 40 / pump 30 / pump 30 / whip 40 / final 90); if the body comes upright mid-sequence the executor jumps straight to the retract so the later stages cannot knock the standing robot over.

7.4 Monitoring and logs

python tools/hw_monitor.py COM27

(Run it in the SR-Support folder with .venv activated - page 02. Close any serial assistant/monitor first; serial tools / the Windows UartAssist download are on page 03, section 3.3.)

• Appends events and 5-second telemetry summaries to logs/hw_monitor.log;
• Records getup start, executor re-plan, standing, executor timeout, IMU lost, etc.;
• Checks the servo envelope (shoulder [-1.85,+1.82], elbow ±1.55) and writes !! VIOLATION;
• While the executor runs it prints a trace every 0.2 s:

executor pose=roll_neg ph=3 tick=9 tgt=(2.00,-0.80) up=(0.58,-0.24,-0.77) q=(2.00,-0.80) sw=0

Field	Meaning
pose	Current reference pose
ph / tick	Waypoint phase / tick within the phase
tgt	Target joint angles
up	Current up vector
q	Current joint command
sw	Number of pose switches so far

Opening the monitor resets the ESP32; close it before flashing.

7.5 Record keeping

For every test record the pose, whether it ended with done, the duration, the number of switches and any violations. logs/hw_monitor.log is the authoritative record.

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