What does a shared pick-and-place robot cost once it has to stay up, and do spares change when sharing beats a robot per job?

What it found

A stdlib extension of osrobot-reconfig adds independent unit failures (availability A) and buys the fewest spares that meet a service target, either per job or for every job at once (200 random job mixes per row, seed 7). While the shared robot's load fits one machine, spares change nothing in the per-job comparison: the shared fleet costs 0.68 of a robot per job at 4 jobs, A = 0.95, target 0.99, with or without spares. Asking every job to be up at once favours sharing (0.34 to 0.51 at 4 jobs, A 0.90 to 0.99; 0.41 at 8 jobs, A = 0.95), because a shared robot fails every job together while four independent jobs each need a spare. At demand 0.3 per job spares close the gap load opened (1.34 bare, 1.01 with spares). Limits: “served in full” is all or nothing, failures are independent with unlimited repair crews, and one assumed availability covers every machine. Stylised; no price or MTBF is sourced.

A figure from its own output

Paper, code and results

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

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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.