Does exact queueing analysis predict a robot-printer cell's throughput better than a utilisation bound?
research/robofab-cell-mva
Exact mean value analysis of the arm, printers and inspection network against a discrete-event twin: a few per cent off for exponential times, up to 11% low for less variable ones, better than the utilisation bound in most real-semantics rows, and it overshoots saturation at high work in process. Stylised.
What it found
Mean value analysis of a closed arm, printers and inspection network, checked against a hand-written discrete-event simulation that adds one departure from product form at a time (illustrative times, 20 seeds). The code matches the exact Markov-chain solution on small networks. With exponential times MVA is within −6% to +4% of simulation; with less variable times it is up to 11% low. With printers held while waiting for the arm, MVA beats the utilisation bound at 4, 8 and 12 printers but not at 16, and it overshoots the saturation plateau at high work in process (9.8 against 8.6 parts/h at 8 printers). Stylised, simulation-only; no physical cell.
A figure from its own output
Paper, code and results
More in Robot manufacturing loops
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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.