How well must a drywall-screwing robot find the framing, and do a few missed screws matter?

What it found

Re-runs the buildbot-studfind error budget with a drywall schedule: 16 in screw pitch on walls (28 screws a sheet) and 12 in on ceilings (36), a #6 screw, 0.9 mm of robot scatter per screw from buildbot-fasten, and a shared reading error per framing member. One read of each member must be good to 1.02 mm (1 sigma) on a wall and 0.98 mm on a ceiling for 95% of sheets to land every screw, close to nailing's 0.89 mm because the two sheet-edge members (±3.9 mm windows), not the screw count, bind. Allowing 1 or 3 missed screws raises that to 1.35 or 1.66 mm; 4 or 16 averaged reads to 2.05 or 4.10 mm; re-measuring each screw (1.00 mm) is no better than a shared read. A stud finder’s ‘within 1/8 in’ claim gives 35% clean wall sheets from one read if taken as 1 sigma, 78% from four. Simulated: reading scatter is swept, not measured; pitch is from a USG FAQ, the 3/8 in edge distance from a gypsum-fibre guide and the screw size is nominal, none read from ASTM C840; reads are assumed independent and Gaussian.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

More in Robots on the building site

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All 27 Robots on the building site projects →

Other research topics

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.