What does a 2-joint feeding arm cost against a 6-joint one once the whole bill of materials is priced?

What it found

osrobot-dof priced servos alone and said extra joints triple the cost. Pricing the whole arm from the published SO-ARM101 parts list (board, cable, power supply, clamps, screwdrivers; the model reproduces the table's $121.94 follower and $229.88 two-arm totals exactly) gives a 6-joint to 2-joint ratio of 1.84 at the table's $13.89 servo ($66.38 against $121.94), 2.15 at a $26.00 retail listing and 2.44 at $49.22; it reaches 2.5 only at a $57.90 servo. Printed links add $1.50 to $4.00 across a swept $15 to $40 per kg filament price. Prices are a snapshot, the 7.4 V and 12 V servo classes are mixed, and camera, mount and safety stop are not priced, so every total is a lower bound. Only the filament price is not from a source (swept).

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.