What limits the battery life of a pendant-style always-on audio wearable?

What it found

A stylised average-current model for an nRF52840-class pendant with a 150 mAh cell, built from a few vendor figures read on 2026-10-13 plus labelled assumptions. The always-on microphone is the floor (about 170 h alone); gating codec and radio on speech at a 30% speech fraction gives about 105 h against 59 h for always streaming. A 74-byte energy-gate routine compiles for Cortex-M4. Nothing is measured on hardware, the datasheets were not read in full and there is no numeric comparison with Omi.

Paper, code and results

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

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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.