Where should a print-failure detector's alarm threshold go in a robot-arm 3D-printer cell?
research/robofab-cell-detector
Where should a print-failure detector's alarm threshold go in a robot-arm printer cell? A look every 2 min makes a z = 2 threshold 19 to 23% worse than blind printing; the best z is 3 to 3.5, worth +6% (d' = 2) to +11% (d' = 4). Stylised.
What it found
Replaces the monitor project's fixed detection delay with a detector that looks at a print every few minutes and has a Gaussian score (separation d′) and an alarm threshold z, and asks which z maximises good parts per hour, with an exact analytic bound and a 40-seed discrete-event simulation (6 printers, 0.3 failures per printing hour, looks every 2 min). A threshold that sounds strict (z = 2, 2.3% false alarms per look) makes the cell 19–23% worse than blind printing for every detector quality, because a 60 min print is looked at 30 times; the best z is 3–3.5, and the gain over blind printing is +5.8% at d′ = 2, +9.7% at 3 and +11.3% at 4, and within noise below d′ of about 1. Stylised: looks are independent, which real consecutive frames are not.
A figure from its own output
Paper, code and results
More in Robot manufacturing loops
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Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & human sciences1
Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.