humanoidrobots.systems

K-Scale Z-Bot (Zeroth Bot) vs Rainbow Robotics RB-Y1

Generated from the registry · revision 2026-09-26 · openness out of 100

Z-Bot (Zeroth Bot) is 94 cm shorter (46 vs 140 cm) than Rainbow Robotics RB-Y1. Z-Bot (Zeroth Bot) has 2 fewer degrees of freedom (18 vs 20) than Rainbow Robotics RB-Y1. Openness score: Z-Bot (Zeroth Bot) 90, Rainbow Robotics RB-Y1 30 (of 100); only Z-Bot (Zeroth Bot) publishes CAD, BOM and FW. Availability: Z-Bot (Zeroth Bot) diy build, Rainbow Robotics RB-Y1 buy.

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Side by side

■ rows differ
Side-by-side specifications. Rows marked with a square differ.
FieldK-Scale LabsK-Scale Z-Bot (Zeroth Bot)Rainbow RoboticsRainbow Robotics RB-Y1Δ first − second
Identity
Maker (differs)K-Scale LabsRainbow Robotics
Class (differs)HumanoidWheeled humanoid
Status (differs)OrphanedActive
Availability (differs)DIY buildBuy
Country (differs)United StatesSouth Korea
Year (differs)20252024
Specifications
Height (differs)46cm140cm−94 cm (-67%)
Mass—unsourced131kg
Degrees of freedom (differs)1820−2 (-10%)
Payload—unsourced3kg
Top speed—unsourced1.5m/s
Runtime—unsourced—unsourced
Battery capacity—unsourced1,250Wh
Price999USD—unsourced
Actuators (differs)18 servo motorsRainbow in-house joint modules
Compute—unsourcedDual-PC (real-time robot PC + user PC with ROS 2)
Sensors (differs)cameras, IMU (per press)Built-in wrist force/torque sensors (v1.2); optional camera
Openness and provenance
Openness bar9030
Openness score (differs)90/ 10030/ 100+60
CAD (25) (differs)publicnot public
Bill of materials (20) (differs)publicnot public
Sim model (URDF/MJCF) (20)publicpublic
Firmware (15) (differs)publicnot public
Software (10)publicpublic
Trained policies (10)not publicnot public
Verification level (differs)L1L2
Sources (differs)32
Last checked2026-09-242026-09-24

A dash is an unsourced figure, not zero. Sources for each robot are listed on its spec sheet: Z-Bot (Zeroth Bot), Rainbow Robotics RB-Y1.

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