When does the textbook milling chatter chart mislead?

What it found

A one-mode, two-tooth milling tool (benchmark values recalled from Insperger and Stepan, not a measured FRF) is analysed three ways: the Altintas-Budak zero-order solution, a semi-discretisation Floquet solution, and an RK4 time-domain simulation with a true delay. The zero-order minimum depth matches the closed form (0.311 mm for slotting) and agrees with the Floquet limit at 50 % up-milling, but at 10 % up-milling it overshoots by up to 3.3 times at some speeds (minimum 0.787 against 0.669 mm), and in down-milling at 10 and 50 % immersion the mean cutting coefficient is negative so it predicts no chatter while the Floquet limit is 0.65 to 0.88 mm. The Floquet multiplier and the time-domain run agree on stability at all 30 test points. Choosing the best spindle speed raises the stable removal rate 5 to 18 times over the minimum stable depth. No public tool-tip FRF was reachable: all tool constants are assumed benchmark values.

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.