Hold shade on the first dyeing
Substrate-aware recipe prediction plus closed-loop exhaust control, with the colourist approving only what deviates.
Blog
Notes from the mill floor
Control theory, colour science, vision at line speed, and what actually happens when you tell a dyehouse an agent will touch the jet.
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Recent writing
Engineering
Shade is a control problem, not a colour problem
Mills treat shade as something you check. The exhaust curve says it is something you steer, and the difference shows up in the re-dye rate.
Architecture
Why the control loop has to live at the mill edge
A dye bath does not wait for your uplink. What we learned putting inference, guardrails and the audit log on Jetson-class hardware inside the dyehouse.
Product
Graduated autonomy: how an agent earns the right to touch a jet
Observe, assist, bounded auto-control. The policy model that lets a mill hand over setpoints one at a time instead of all at once.
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From the archive
Research
Generating the defects you hope never to see
Barré, skew and pin-chain streaks are rare, expensive and badly labelled. Synthetic generation, and how we score it against real mill outcomes.
Sustainability
The water-per-kilo number your mill is not measuring
Most mills know their monthly water bill and not their litres per kilogram per shade family. That gap is where the savings hide.
Product
Roll genealogy: the boring feature buyers actually buy
Bale to bolt, immutable, exportable. Why traceability closes enterprise deals that model accuracy does not.
Featured
Shade is a control problem
Most mills treat shade as an inspection step: dye the lot, pull a swatch, read it on the spectrophotometer, and find out whether the last four hours were worth anything. That framing is why re-dye rates stay stubbornly high at many commission houses.
The exhaust curve says something different. Dye uptake over time is a trajectory, and a trajectory is steerable. If you can observe bath concentration, temperature and substrate response continuously, and you have a model of how this fibre, this water and this dye class behave together, then shade stops being a measurement and becomes a setpoint problem.
The hard part is not the model. It is the substrate. A standing recipe card assumes one greige quality and one water profile; the reality on a commission floor is nine suppliers and seasonal hardness swings. Any control law that ignores that will be confidently wrong.
So the agent conditions on substrate: pre-treatment absorbency, residual alkalinity, water hardness, and the mill’s own history of how this combination behaved. Then it simulates against the twin, proposes a recipe, and, where the deviation exceeds the mill’s autonomy ceiling, stops and asks a colourist. In the scenario run RUN-4471 on this site, that is a 7.2% deviation and a fifteen-minute wait, and the lot lands at ΔE 0.58 against a 0.80 tolerance.
Run timeline
RUN-4471 · Indigo poplin, 3,180 kg, due Thursday
The same scenario run as an ordered timeline: step, status, duration and the tool result behind it. Inspection failed on one roll, the run recovered, replanned the cut and still held the ship date.
RUN-4471
RUN COMPLETE
Scenario mill · reactive exhaust jet dyeing · illustrative run, not a customer deployment
Goal: Dye lot DL-4471 · 3,180 kg · 40s combed cotton poplin · shade Indigo 19-4028 TCX · ΔE ≤ 0.8 · due Thu 06:00
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01 ingest.lot_state SUCCEEDED 0.8s
Pulls greige genealogy for 14 rolls: yarn lots, loom, greige GSM 138, absorbency and residual size from the prep line.
Agent, input and output
agent Quality-and-Conformance result ← 14 rolls · 3,180 kg · mean GSM 138.2 (σ 1.1) · prep OK -
02 twin.simulate_lot SUCCEEDED 46s
Omniverse fabric-line twin simulates the exhaust curve, machine loading and takt for three candidate recipes before a drop of dye is used.
Agent, input and output
agent Yield-and-Takt result ← 3 candidates scored · best predicted ΔE 0.52 · 118 min cycle -
03 dye.predict_recipe SUCCEEDED 2.4s
Spectral recipe model proposes a 3-dye combination against the buyer standard, corrected for this substrate’s absorbency and the current water hardness.
Agent, input and output
agent Dye-and-Color result ← 2.14% Navy RGB · 0.61% Blue BRF · 0.08% Black B · salt 62 g/L -
04 human.approve_recipe APPROVAL 4m 12s
Recipe deviates >5% from the standing card, so autonomy is capped: the colourist approves, rejects or edits before any dosing. Guardrail policy MILL-02/DYE-APPROVAL.
Agent, input and output
agent Dye-and-Color result → awaiting colourist · approved on shift 04:18 -
05 dye.control_bath SUCCEEDED 118m
Closed-loop dosing and ramp control against live bath spectrophotometry; two mid-cycle corrections applied when exhaustion ran 4% ahead of model.
Agent, input and output
agent Dye-and-Color result ← exhaust 96.4% · 2 corrections · bath ΔE 0.41 at drain -
06 shade.verify_lot SUCCEEDED 9.1s
Per-roll spectral read against Indigo 19-4028 TCX under D65/TL84/A; metamerism scored and rolls sorted into shade bands.
Agent, input and output
agent Shade-and-Quality result ← mean ΔE 0.58 · 13 rolls band A · 1 roll band B -
07 finish.control_stenter SUCCEEDED 64m
Stenter chemistry, overfeed and curing profile set to hold hand, 148 cm width and residual shrinkage under 3%.
Agent, input and output
agent Finish-and-Hand result ← width 148.3 cm · shrink 2.1% warp / 1.4% weft -
08 inspect.scan_rolls FAILED 38m
In-line vision flags a recurring 6 cm weft streak on roll 09 between 412 m and 445 m, traced to a stenter pin-chain slip, not a dye fault.
Agent, input and output
agent Defect-and-Inspect result ← 1 defect cluster · roll 09 · 33 m affected · class WEFT_STREAK -
09 plan.rework_route SUCCEEDED 1.6s
cuOpt re-plans the cut and rework route: 33 m diverted to seconds, remaining 14,890 m re-sequenced so the buyer’s Thursday ship date still holds.
Agent, input and output
agent Yield-and-Takt result ← 33 m to seconds (0.22%) · ship date held -
10 quality.grade_and_release SUCCEEDED 3.0s
Four-point grading, roll genealogy and the conformance packet (AATCC 61, ISO 105-C06, ZDHC MRSL declaration) are assembled and released to the buyer portal.
Agent, input and output
agent Quality-and-Conformance result ← 13 rolls Grade A · 1 roll Grade B · packet signed
RUN OUTCOME
Lot released first time, on shade, on date.
| Measure | Value | Context |
|---|---|---|
| Final mean ΔE | 0.58 | against a 0.80 tolerance |
| Re-dyes avoided | 1 | the standing card would have missed shade |
| Seconds | 0.22% | versus the scenario mill baseline of 1.9% |
| Water used | 46 L/kg | versus 59 L/kg on the scenario recipe card |
| Human decisions | 1 | the recipe approval gate |
Why this matters
A mill does not fail on the good lots. It fails on the lot where the substrate drifted, the recipe card was wrong, and nobody found out until the buyer opened the carton. Yarneon makes that lot legible while it is still in the machine.
Reasoning trace
The reasoning, written down
Goal, observation, plan, action, decision, handoff, outcome. A colourist can read this and disagree with it, which is the point. Autonomy a mill cannot argue with is autonomy a mill will not adopt.
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Land DL-4471 on Indigo 19-4028 TCX within ΔE 0.80, first time, before the Thursday 06:00 ship cut-off.
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Greige absorbency for this lot reads 8% above the card baseline, and incoming water hardness is 142 ppm, both push the exhaust curve faster than the standing recipe assumes.
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Simulate three recipes in the fabric twin before committing dye. Prefer the candidate with the lowest predicted ΔE that also fits the 118-minute machine slot.
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twin.simulate(recipe_candidates=3, machine="jet-07")
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Candidate B predicts ΔE 0.52 and finishes 6 minutes inside the slot. Candidates A and C either overshoot shade or miss takt.
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Candidate B deviates 7.2% from the standing card, above the 5% autonomy ceiling for dye dosing. Escalate to the colourist rather than act.
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Dye-and-Color → the colourist on shift, with the simulated curve, the deviation reason and a one-click revert attached.
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plc.dose(machine="jet-07", schedule="ramp-B") after approval, with two mid-cycle corrections when exhaustion led the model by 4%.
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Vision flags a 33 m weft streak on roll 09 after finishing. Correlating stenter telemetry shows a pin-chain slip at 04:51, a mechanical cause, not a dye fault.
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Lot released at mean ΔE 0.58 with 0.22% seconds. A maintenance work order is raised against the stenter pin chain, and the streak signature is added to the mill’s defect memory.
Human in the loop
Craft is captured, not replaced
Textile mills run on scarce craft: the colourist who knows this jet runs hot, the weaving master who hears a beam going wrong. That knowledge is retiring faster than it is being replaced.
Yarneon writes it down. Every approval, override and correction becomes per-mill memory scoped to your tenant, so the mill keeps improving after the person who taught it has gone home.
- Per-colourist and per-operator performance memory
- Overrides captured as training signal, not noise
- Versioned memory, scoped per tenant, never shared across mills
Agent graph
One run, ten steps, one human decision
This is the shape of a dye lot on Yarneon, shown as an illustrative scenario rather than a customer run. Ingest and simulation fan out, converge on a colourist approval gate, then dosing, verification, finishing, inspection and release. The accent traces the active path; every node opens in the inspector.
Scroll the graph sideways · or open the text equivalent below
SUCCEEDED APPROVAL FAILED RUNNING
Text equivalent, workflow steps, dependencies and status
| Step | Stage | Depends on | Status | Duration |
|---|---|---|---|---|
| ingest | conformance | none | SUCCEEDED | 0.8s |
| twin | simulate | ingest | SUCCEEDED | 46s |
| recipe | dye + colour | ingest | SUCCEEDED | 2.4s |
| approve | human gate | twin, recipe | APPROVAL | 4m 12s |
| dose | bath control | approve | SUCCEEDED | 118m |
| shade | verify ΔE | dose | SUCCEEDED | 9.1s |
| finish | stenter | dose | SUCCEEDED | 64m |
| inspect | vision | shade, finish | FAILED | 38m |
| rework | replan | inspect | SUCCEEDED | 1.6s |
| grade | release | rework | SUCCEEDED | 3.0s |
- Parallel branches2twin simulation and recipe prediction run together
- Human gates1colourist approval, 15 minutes, attributed
- Failures recovered1weft streak on roll 09, replanned in-run
Tool-call stream
Every call the agent made, in order
Machines, spectrophotometers, the optimiser and the humans are all tools. Calls go out, results come back, and the whole exchange is real, copyable text, the same record your auditor sees.
04:02:11
result: mes.get_lot("DL-4471") → 14 rolls · 3,180 kg · poplin 40s
SUCCEEDED
04:02:12
call: twin.simulate(recipe_candidates=3, machine="jet-07")
RUNNING
04:02:58
result: twin.simulate → best ΔE 0.52 · cycle 118 min · water 46 L/kg
SUCCEEDED
04:03:01
call: colour.predict_recipe(substrate="cotton", standard="19-4028 TCX")
RUNNING
04:03:03
result: colour.predict_recipe → Navy RGB 2.14% · Blue BRF 0.61% · Black B 0.08%
SUCCEEDED
04:03:04
call: policy.check(action="dose", deviation=7.2%) → requires human approval
APPROVAL
04:18:22
result: human.approve(user="colourist-on-shift", decision="approve", note="ok, hold ramp")
SUCCEEDED
04:18:24
call: plc.dose(machine="jet-07", schedule="ramp-B")
RUNNING
05:41:07
result: spectro.read(bath) → exhaustion 96.4% · bath ΔE 0.41
SUCCEEDED
06:22:40
result: vision.scan(roll=09) → WEFT_STREAK 412–445 m · severity 3
FAILED
06:22:41
call: cuopt.replan(cut_plan, constraint="ship_thu_0600")
RUNNING
06:22:43
result: cuopt.replan → 33 m to seconds · ship date held
SUCCEEDED
06:25:02
result: quality.release(lot="DL-4471") → 13 Grade A · 1 Grade B · packet signed
SUCCEEDED
Guardrail in action
policy.check → requires human approval
At 04:03:04 the proposed recipe deviated 7.2% from the standing card, above the 5% autonomy ceiling for dye dosing at this mill. The agent stopped and asked. Fifteen minutes later a colourist approved it, and that approval is attributed, timestamped and reversible.
Failure handled honestly
vision.scan → WEFT_STREAK, roll 09
A 33 m weft streak is a real defect, and the run shows it as failed rather than smoothing it over. The mechanical root cause, a stenter pin-chain slip, was correlated automatically and raised as a work order.
Operating figures
The numbers a mill manager asks about second
Latency targets, connector coverage, autonomy modes and the record: the practical questions after the headline.
<100 ms
Design target for a per-frame inspection decision on Jetson-class edge hardware. ASPIRATIONAL
8
Connector families: looms, frames, dyeing, colour, inspection, MES, utilities, robotics.
3
Autonomy modes: observe, assist, bounded control. Granted per setpoint.
1
Record per mill: append-only, exportable, shared with buyers on request.
Items marked ASPIRATIONAL are design targets ahead of production validation.
Use cases
What mills point Yarneon at first
Every deployment starts with one wedge workflow that pays for itself, then expands along the line.
Catch defects at the machine
Line-scan and NIR vision classify slubs, holes, streaks, stains, floats, barré and skew at full line speed, mapped to roll position.
Stop end-breaks before they cascade
Evenness and draft telemetry predict end-break clusters on ring frames and adjust before the frame sheds packages.
Keep construction on spec
Warp and weft tension control across air-jet, rapier and circular-knit machines holds pick and course density inside tolerance.
Hit hand, width and shrinkage
Stenter chemistry, overfeed and curing profiles tuned per construction so finished goods pass dimensional-stability tests.
Band rolls by shade before cutting
Spectral scoring sorts rolls into shade bands so no garment is cut from two shades.
Sequence dye lots for water and takt
Shade-family aware sequencing under delivery and machine constraints cuts changeovers, water and steam.
Automate doffing and roll transport
Vision-guided manipulators and AMRs take the lifting out of the job that mills cannot staff.
Produce the buyer packet automatically
Roll genealogy, test methods and chemistry declarations assembled and signed at release.
Design-partner programme
What a design partnership involves
Three to five mills, one wedge workflow each, shadow mode first. The sequence comes from our MVP plan and does not change for anyone.
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Phase 1
Instrument
The wedge workflow is connected in shadow mode and the baseline for seconds, re-dyes and waste is measured from the mill’s own data.
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Phase 2
Assist
The agent recommends yarn, construction and recipe moves and predicts defects and shade. An engineer approves each one, and accuracy is scored in the open.
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Phase 3
Graduate
Low-risk inspection, dye and finishing loops move to bounded auto-control one setpoint at a time. Exceptions escalate to a named person.
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Phase 4
Expand
Adjacent modules are added within the same mill once the wedge holds its numbers. Publication of results is the mill’s decision.
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