Amazing Hand is an open-source 8-DOF humanoid hand that packs all its actuators inside the palm — no cables, no deported motors, no forearm clutter. Derived from Pollen Robotics' expertise on Reachy 2, it brings professional-quality dexterity at under 200€. Four fingers, each with two degrees of freedom (flexion/extension and abduction/adduction), are driven by parallel mechanisms using pairs of Feetech SCS0009 micro servos. The result is a surprisingly expressive hand that can grasp, pinch, point, spread, and form complex gestures. **Key specs:** - **DOF:** 8 (2 per finger × 4 fingers — index, middle, ring, pinky) - **Mechanism:** Parallel mechanism per finger — both joints driven simultaneously by 2 servos - **Servos:** 8× Feetech SCS0009 (serial bus, compact) - **Weight:** ~400g assembled - **Build cost:** Under 200€ (including servos) - **Wrist interface:** Designed for Reachy 2's Orbita 3D wrist, adaptable to other platforms - **SO-ARM100 interface:** Adapter STL included for mounting on SO-ARM100 **Design philosophy:** The parallel mechanism is the key innovation: two servos actuate each finger through a gimbal linkage, decoupling flexion/extension from side-to-side movement without requiring tendons or cables. All 8 actuators are housed within the palm housing, keeping the wrist clean and the arm kinematics unaffected. **Control:** Two modes: Python serial bus (using a Waveshare SC driver board) or Arduino + Feetech TTL Linker. Both methods and demo code are included in the repository. An "Amazing Hand Enhanced" branch extends this design with additional capabilities — see the repo for the latest. Code licensed under Apache 2.0. Mechanical design licensed under CC BY 4.0. Original design by Pollen Robotics — https://github.com/pollen-robotics/AmazingHand
Category: Robotic Hands
| Item | Qty | Unit Cost (USD) | Notes | |---|---|---|---| | Feetech SCS0009 Serial Bus Servo | 8 | $7.85 | 2 per finger; primary actuator | | Ball joint M2 L19 | 16 | $1.21 | Linkage joints | | M2 threaded rod L300mm | 1 | $1.88 | Cut to length | | Axis D2 x 10mm | 8 | $0.55 | Pivot pins | | Axis D2 x 16mm | 8 | $0.88 | Pivot pins | | Bushing 6mm ID / 8mm OD | 8 | $1.76 | Joint bushings | | Thermoplastic screw 2.5x6mm | 16 | $0.01 | Self-tapping | | Thermoplastic screw 2.5x8mm | 30 | $0.01 | Self-tapping | | Washer M2.5, 8mm OD | 4 | $0.47 | Spacing | | WaveShare Serial Bus Servo Driver Board | 1 | $12.50 | Controller (Option 1) | | Arduino Mega 2560 (alt controller) | 1 | $26.40 | With Feetech TTL linker (Option 2) | | Feetech TTL Linker (for Arduino path) | 1 | $1.54 | (inferred — only for Option 2) | | 5V 2A DC Power Supply (5.5x2.1 jack) | 1 | $10.00 | (inferred from README note) |