Does holding the printer through load and unload fix queueing analysis of a robot-printer cell?
research/robofab-cell-held
Does adding load and unload time to the printer's demand fix MVA of the robot-printer cell? Mixed: it cuts the error at saturation (2.9% against 8.2%) but raises it elsewhere (7.3% against 3.6%), so overall plain MVA is better (4.7% against 6.2%). Stylised.
What it found
A follow-up to the variability-sweep project: mean value analysis with the printer demand increased by the arm’s load and unload time, compared with plain MVA and two utilisation bounds against the simulated cell (cv 0.3 and 1.0, 4–16 printers, four loads, 20 seeds, 32 settings; illustrative times). The repair helps only at saturation (mean absolute error 2.9% against 8.2% for plain MVA) and hurts elsewhere (7.3% against 3.6%), so over all settings plain MVA is better (4.7% against 6.2%). A mixed result: no single demand setting is right across loads. Stylised and simulation-only.
A figure from its own output

Paper, code and results
More in Robot manufacturing loops
- Does an arm-wait-aware printer demand fix queueing analysis of a robot-printer cell?Does adding the arm's queueing delay (a fixed point, no fitted parameter) to the held printer's demand fix MVA of the robot-printer cell? No: it underpredicts in all 32 settings and is worse overall (7.9% mean error against 6.2% for held-demand and 4.7% for plain MVA). Negative result. Stylised.
- Can a blocking-aware correction to queueing analysis predict a robot-printer cell across loads?Can a blocking-aware correction to MVA predict the held-printer robot cell across loads? A fitted stall helps only at saturation (1.4% error) and worsens other loads (8.5%); keeping latency apart from capacity gives 3.6% against plain MVA's 4.7% on the design grid, but only ties plain MVA (3.4% against 3.5%) on a held-out job mix. Stylised.
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All 53 Robot manufacturing loops 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.