# AutoCal workflow — platform bring-up to calibration data

This is the operating workflow the application is built around. It is written to
be argued with: each phase names what it needs, what it produces, why it exists,
and what must be true before the next one starts.

A **gate** is a checkpoint. The app's job at a gate is to make the operator's
answer trustworthy, not to ask "are you sure?".

```text
P0  Session & safety baseline            [gate]
P1  ECAT setup                           [gate]
P2  Homing + test motion                 [gate]
P3  Sensor & probe setup                 [gate]
P4  Coordinate setup: sensor <-> platform [gate]
P5  Sequence design                      [gate]
P6  Simulate & dry run                   [gate]
P7  Run + acquire                        [gate]
P8  Store raw
P9  Post-process                         [gate]
P10 Calibration export
P11 Verify                               [gate]
```

---

## P0 — Session & safety baseline

**Why:** the machine can move from P2 onward. Everything that limits that motion
should be decided while nothing is moving.

**Inputs:** operator identity, machine/bench identifier, units per axis,
`units_per_mm`.

**Safety limits, set here, enforced from P2:**

| Limit | Meaning |
|---|---|
| maximum travel per axis | never commanded past this, in user units |
| maximum Z descent per step | a single approach may not exceed this |
| press-depth ceiling | the press depth a sequence profile is allowed to request |
| no-contact abort | if contact is not detected within the descent budget, stop the run |
| following-error bound | how far a drive may lag before the move counts as stalled |

**Outputs:** a session record — who, when, which machine, and the limits in
force. Stamped onto everything the session produces.

**Gate:** every limit has a value; no limit is "unset" (an unset limit is an
unlimited machine).

**Currently missing from the workflow:** this phase did not exist. Without it,
step 1 went from bus setup straight to jogging five axes.

---

## P1 — ECAT setup

**Why:** nothing else can be trusted until the controller has actually found its
slaves. A missing drive discovered at P7 wastes the whole run.

**Inputs:** controller address, the matching `.bas` program
(`ECAT.bas` / `RTEX.bas`).

**Steps:** connect → **adopt a program the controller is already running, or
download one if `BUS_TYPE` is unreadable** → watch `Bus_InitStatus` to completion
or timeout → read `BUS_TYPE`, `Bus_TotalAxisnum`, and the node count. Step 2 is
conditional because a controller usually still has the program in ROM from the
last session, and a download is a bus re-scan the operator did not ask for.

Both controls live in the **device setup dialog** (设备设置), opened from the status
strip's button, its connection/bus/init chips, or 文件 → 设备设置: they are used once
per machine start-up, so the rail keeps only what is read while working. The strip
continues to report connection, bus and init state while the dialog is open or shut.

**Re-initialising without a download:** `STOPTASK <task>` then
`RUN "<file>",<task>`, on the task from `bas_task` in `preference.json`
(default 4 — the task the vendor reference uses; stopping another task restarts
nothing). Two things are easy to get wrong here, and both have been:

- the file name must be the one the *controller* has. When the session adopted a
  running program, the controller does not report the name, so the app carries
  the remembered `bas_path` into the connect for exactly this purpose;
- the controller answers a `RUN` naming a file it does not have with **code 0**
  and the diagnosis in its reply text. The reply is checked, and its text is
  shown instead of reporting an initialisation that is not happening.

**Outputs:** bus type, node count, axis count, init status.

**Gate:** init status is success, **and** the node/axis counts match what this
bench is expected to have. A mismatch is a finding, not a warning.

**Existing code:** `MotionService.download_bas` / `reinit_bus` / `poll` implement
the state machine and the 25 s timeout.

**Connection faults are a different family.** A `ZAux_*` code in 20000–29999 is a
PC-library fault (handshake, socket, address), not a controller code: ZDevelop's
table cannot contain it, so the app answers it with cable/IP/no-second-client
advice and retries an Ethernet open up to three times, because a first open on a
cold route can fail and succeed immediately after. `20008` at the bench was that
case.

---

## P2 — Homing + test motion

**Why:** a drive that homes and jogs cleanly at low speed is the precondition for
letting a sequence drive it.

**Inputs:** per-axis homing mode, speeds, offset; a test-motion profile.

**Steps:** enable → home each axis → low-speed jog each axis in both directions
→ confirm movement and return.

**Outputs:** per-axis pass/fail with the evidence (distance moved, following
error, alarm state).

**Gate — the test motion needs a criterion.** This was missing. Proposed:

- the axis moved at least a configured minimum distance;
- it returned within a tolerance of its start position;
- following error stayed under the bound from P0;
- no alarm before, during or after.

**Existing code:** the axis panel does the jog/homing; the criterion is new.

---

## P3 — Sensor & probe setup

**Why:** which sensor is under test, what touches it, and how far the touching
point is from the axis reference. Contact depth is meaningless without the tool.

**Inputs:**

- sensor type and config reference (the same `config/sensors/<type>/sensor.json`
  the studio uses);
- the sensor's 3D scene package and its `geometry_id`;
- the **probe tip** (tool): which axis presses, and the tip offset from the
  platform's reference point;
- the mounting pose: how the sensor is fixtured on the platform.

**Outputs:** a saved setup block.

**Gate:**

- the calibration's `geometry_id` matches the scene's, or the app says which is
  which rather than colouring the wrong geometry;
- the probe tip offset is set (a zero offset that was never entered is not the
  same as a probe at the origin).

---

## P4 — Coordinate setup: sensor ↔ platform

**Why this is the load-bearing phase.** "Which points on the sensor should be
tested" is a question in the *sensor's* frame. The platform moves in *platform*
coordinates. Without the transform between them:

- a generated grid cannot be checked against the sensor's surface;
- a measured point cannot be placed on that surface for the sensitivity map;
- a calibration cannot be re-applied to a re-fixtured sensor.

**Inputs:** the probe tip from P3, and a set of **at least four non-collinear
known features** on the sensor or its fixture, probed in platform coordinates.

**Steps:** probe each feature → solve for the rigid transform (rotation and
translation; scale if the units are not yet trusted) → report the residual.

**Outputs:** a 4×4 transform from sensor frame to platform frame, with its
residual and the feature set that produced it.

**Gate:** residual under a configured tolerance, and at least four non-collinear
points (four collinear points determine a rotation about that line, not a
transform — the app should refuse that set rather than return a number).

**Not built in this step:** the solver. Only the workflow step, the stored
transform, and the place its residual is displayed.

---

## P5 — Sequence design

**Why:** this is the decision the whole run exists to carry out.

**Inputs (the profile, persisted and reusable):**

| Parameter | Meaning |
|---|---|
| mode | flat surface or curved (a cylindrical/spherical sensor area) |
| grid pitch | spacing between points, in mm |
| margin / radius | how far in from the active edge the grid stays; radius for curved |
| clear height | standoff above the surface to travel at |
| approach speed | descent speed before contact |
| press speed | descent speed after contact |
| press depth | how far past contact to press |
| dwell | how long to hold the press |
| settle window | how long to wait before the measurement is considered settled |
| repeats | how many times each point is measured |
| point order | row-wise, serpentine, or by distance |

**Steps:** generate the grid → validate **every point** three ways:

1. **on the sensor** — its sensor-frame position falls on the modelled surface,
   not off the edge and not inside a hole;
2. **within travel** — the platform can reach it inside the P0 limits;
3. **confirmable** — the sensor's sensing area is under the point, so a contact
   there can actually be seen by the sensor.

**Outputs:** a point list with a sensor-frame position and a platform-frame
target for each, plus a validation verdict per point.

**Gate:** no point may be unusable without being marked as such. A run may
proceed with skipped points if the operator says so explicitly; it may not
proceed with unvalidated ones.

**The interface:** three zones in the Sequence tab — profile parameters, a 3D
preview of the surface with the points and their visiting order, and the
validation list. See `apps/autocal/README.md`.

---

## P6 — Simulate & dry run

**Why:** a wrong Z or a wrong grid is much cheaper to find now.

**Simulate:** play the full toolpath in the 3D view — a moving marker with a
phase label (standoff → descend → press → dwell → retract), the estimated
duration, and per-point reachability. No motion.

**Dry run:** execute the real XY path, descending only to the clear height,
never pressing. This proves the geometry, the ordering, and the timing.

**Outputs:** estimated duration, per-point reachability, and (dry run) the
measured time per point.

**Gate:** the operator has seen the path and a dry run has completed without a
guard violation.

**The single-point dry run is built**, in the finger debug screen: 执行动作 sends the
selected point's *solved pose* to the platform — the stages together with the table
X/Y, and the press axis only once its zero is calibrated (设备设置 → 压轴); until then
it is held, so the move cannot reach the sensor by accident. The order follows the
model's own composition (`R_pitch · R_yaw`), so every intermediate pose is one the
operator watched in the preview. Before it moves it checks the mapping, the target
against the P0 limits (millimetres for x/y/z, degrees for yaw/pitch) and the rotary
calibration — all in `motion/service.py`, so a later caller cannot walk around them.
停止 next to it is the same command as the strip's 全部停止; 回初始位 in the rail sends
every axis to zero with the press axis first.

---

## P7 — Run + acquire

**Why:** the only phase that touches the sensor.

**Per step, in order:**

1. move to the point's XY at clear height;
2. descend at approach speed;
3. **detect contact by position** — the axis stalls / following error rises
   while descending;
4. **confirm with the sensor under test** — its reading must change when the
   probe presses. This is the second opinion: position says "I stopped moving",
   the sensor says "something real is happening";
5. press to the configured depth at press speed;
6. dwell, then acquire the settle window;
7. retract, move to the next point.

**Failure semantics (per point, because resume needs them):**

| Outcome | Run behaviour |
|---|---|
| contact confirmed | record the point as measured |
| contact detected, sensor shows no change | mark **suspect**, continue; a suspect point is visible, not silently averaged in |
| no contact within the descent budget | **abort** the run (P0 limit) and leave the point unfinished |
| guard violation | abort the run, name the step and the limit |

**Writes are incremental**: each point is written as it completes, with its
status, so an interrupted run resumes at the first unfinished point and partial
data stays valid.

**Existing code:** the motion layer has the guards and the poller; the step
machine, the contact detection and the acquisition binding are new.

---

## P8 — Store raw

**Why:** post-processing will change. The raw record must not.

**Contents:**

- the sequence profile and the instantiated point list (positions and order);
- per point: the position trace, the raw sensor series, the settle window used,
  timings, the contact position, and the status;
- the setup: sensor identity, geometry id, probe tip, the P4 transform and its
  residual;
- the session record and app/version stamps from P0.

Nothing derived is authoritative. The requirement that makes this reproducible:
**a dataset can be regenerated from the profile, the setup and the raw series**,
with no dependency on a previously computed result.

---

## P9 — Post-process

**Why:** turning samples into a number is a decision, and it has to be visible.

**Steps:** choose the settle window per point → stability check (is the point
actually settled, or drifting?) → sensitivity per point per axis → outlier
detection → residual per point → fit the surface across points.

**Outputs:** per-point sensitivity with a quality verdict, and a surface field
over the sensor's geometry ready for the 3D colour map.

**Gate:** every point is either valid or explicitly excluded, with a reason.
A point with too few samples or a drifting window is not a coefficient.

---

## P10 — Calibration export

**Per-point results and the fitted surface, explicitly linked.** They are one
calibration; exporting them as unrelated artefacts is how a map ends up in a
report that does not match the table beside it.

---

## P11 — Verify

**Why this exists:** P9 and P10 produce numbers. Nothing yet checks they are
right. "Post process → calibration data" had no acceptance test.

**Steps:** apply the calibration → re-measure a small subset of the points →
compare the measured sensitivity against what the calibration predicts →
report the discrepancy per point.

**Gate:** the discrepancy is within tolerance, or the verification is recorded
as failed. A calibration that was never verified is labelled as such wherever it
is used.

---

## Gaps this document closes

| # | Gap | Phase |
|---|---|---|
| 1 | no limits before motion | P0 |
| 2 | no session identity (who/when/which machine) | P0 |
| 3 | the sensor↔platform transform was absent | P4 |
| 4 | the probe tip (tool) was never defined | P3 |
| 5 | the test motion had no pass/fail criterion | P2 |
| 6 | grid validity was not checked per point | P5 |
| 7 | the settle window and stability criterion were undefined | P9 |
| 8 | a point's failure had no defined behaviour | P7 |
| 9 | the sequence was transient, not a saved, versioned artefact | P8 |
| 10 | no verification pass | P11 |

## Data flow

```text
P0 limits ─┬───────────────────────────────> enforced at P2, P6, P7
P1 bus ────┴─> axis availability ─────────> P2
P3 sensor setup ─┬─ geometry id ──────────> P5 validation, P10 surface
                 └─ probe tip ────────────> P4, P7 press depth
P4 transform ─────> sensor <-> platform ──> P5 point generation, P9 map
                   (residual)                P11 re-fixture check
P5 profile + points ──> P6 simulate/dry run ──> P7 run
P7 raw series ─────> P8 dataset ──> P9 post-process ──> P10 export
                                                          └─> P11 verify
```