How well must a nailing robot find the studs, and does measuring more beat measuring better?

What it found

buildbot-fasten left stud-finding as the unmodelled term in the nailing budget. Here every nail on a stud shares that stud's position error, and a 4x8 sheet has four studs (two joints of 17 nails with a ±3.9 mm window, two intermediate studs with ±17.4 mm) and 14 plate nails, with 0.9 mm of robot scatter on each nail. Quadrature and Monte Carlo agree (within 0.01). A single read of each stud must be good to 0.89 mm (1 sigma) for 95% of sheets to land all 62 nails in their windows; at 3 mm only 31% do. A stud finder's vendor claim (‘within 1/8 in’) gives 28% clean sheets and 8 of 62 nails missed if read as 1 sigma, 69% and 1.1 missed if read as a 95% bound. Averaging n reads allows √n more scatter (3.56 mm at 16 reads); pooling the studs of a wall through a 16 in grid allows 2.95 mm for a perfectly straight wall and nothing once layout scatter reaches 4–8 mm; re-measuring at every nail is worst (0.86 mm), because 62 independent errors must all be small where a shared one is four draws. Simulated: reading and layout scatter are swept, not measured; the vendor figure is a claim with an unstated statistic; reads are assumed independent and Gaussian; no camera or wall is modelled.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
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More in Robots on the building site

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• How long a step can a stock Unitree G1 or H1 take carrying lumber, and does that beat a labourer's carry rate?Can a stock humanoid carry a stud faster than a labourer? A MuJoCo single-support step envelope: the G1 steps 0.50 m with one 2x4 and cannot carry two; the H1 steps 0.20 m with one and 0.10 m with 15 kg; neither beats a labourer who takes a bundle of four, and the model is restrictive (no falls, drops or energy scored).
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• Can a stock Unitree G1 or H1 humanoid carry a stud across a site floor as fast as a labourer?Can a stock Unitree G1 or H1 carry a stud as fast as a labourer? A pendulum gait with no trunk compensation gets the G1 to 0.25 m/s unloaded and 0.10 m/s at 4 kg; a robot with one piece per trip would need 4-13 m/s to match a labourer carrying three.

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.