How much cable bend can a waist-mounted exosuit power train tolerate before the shank layout wins?

What it found

Replaces the assumed Bowden-cable efficiency in the shank-versus-waist model with the capstan law exp(−μθ) for friction μ and total bend θ. At gain 0.3, a 4 h battery, 8 N m/kg and an assumed penalty ratio of 3, the waist layout stays ahead until about 31 rad of bend at μ = 0.1 (about 15 rad at 0.2), far beyond a hip-to-ankle route, so energy lost to friction does not decide the layout. Hysteresis, backlash and pretension are not modelled, and μ and the ratio are assumed. Stylised.

A figure from its own output

Paper, code and results

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

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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.