Does it pay to move an exosuit's motor and battery from the shank to the waist?

What it found

Extends the exosuit power-train model with where the mass sits: a kg at the shank costs an assumed multiple of a kg at the waist, and a waist layout pays a Bowden-cable loss (efficiency 0.6–1.0) and keeps 0.3 kg of cable at the ankle. At gain 0.3 with a 4 h battery the waist layout wins once the shank penalty exceeds 1.03–1.39× the waist one; at ratio 3 and 8 N m/kg the shank suit is +20.7% against +3.3% for the waist suit. The ratio is assumed, not sourced, so the result is the break-even, not a prediction. Stylised.

A figure from its own output

Paper, code and results

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

More in Engineered clothing

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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.