SCS0009 vs PWM Version Comparison and Selection
AmazingHand's hand mechanics are the same, but there are two servo options. Selection mainly depends on whether you need position feedback, precise angle control and data collection.
Quick conclusion
- Choose SCS0009: you need position/temperature/voltage readback, precise angles, and integration with an SO-ARM101 robot arm for LeRobot data-collection training.
- Choose PWM: standalone demos, gesture interaction, quick web/desktop start, and no feedback needed.
- Do not mix them: connect only one hardware set at a time; power, protocol and firmware all differ.
Full comparison
| Item | SCS0009 serial bus version | PWM servo version |
|---|---|---|
| Why choose it | Precise angle control + data readback; can integrate with an SO-ARM101 arm for LeRobot data-collection training | Standalone demos, gesture interaction, quick start |
| Servo model | Feetech SCS0009 serial bus servo ×8 | PTK 7452 MG-D digital PWM servo ×8 |
| Servo specs | 2.3 kg·cm@6V, 300° controllable, 0.293° resolution | 4.5 kg·cm@7.4V (about 2.8–3 kg·cm at this solution's 5V supply), 180°±10°, 333 Hz refresh |
| Position/temperature/voltage/speed feedback | ✅ readback supported | ❌ no readback; stall or step loss cannot be detected |
| Controller | none onboard; PC/Raspberry Pi connects directly through the bus driver board | ESP32-S3 onboard firmware |
| Hub | servo driver board + 9-port serial bus hub | PWM adapter board (8 × 3P headers + 5V/GND) |
| Power | 7–12V (DC5521) into the driver board; servos are nominally 6V class | 5V / 3A or more; the adapter board and ESP32 must share a common ground |
| Baud rate | 1,000,000 | no baud rate on the servos; host ↔ ESP32 serial at 115200 8N1 |
| Servo ID | must be set: right hand 1–8, left hand 11–18 | no ID; fixed channels CH1–CH8 (index 1/2, middle 3/4, ring 5/6, thumb 7/8), identical wiring for left and right hands |
| Communication link | host → driver board → bus → 8 servos | host → USB serial 115200 → ESP32 → 8 PWM channels |
| Command format | Feetech bus protocol, angles sent directly | binary frames: 0x01–0x0A / 0x0C gestures, 0xF0 direct drive, 0xF1 left/right hand, 0x00 NOP, 0xFE repeat, 0xFF stop |
| Firmware | none (no flashing needed) | ESP-IDF build, or flash the prebuilt amazinghand_pwm.bin directly |
| Left/right hand | different servo IDs (right 1–8, left 11–18) | same set of channels, code mapping + 0xF1 to select the side |
| Torque release | torque on/off and release supported | not supported; an emergency stop only aborts the gesture, and the servos stay powered and hold position |
| Speed control | speed parameter supported | direct-drive frames have no speed parameter |
SCS0009 version highlights
- Each servo has a unique ID; right hand 1–8, left hand 11–18. After rewiring or replacing a servo, the ID must be set again.
- Uses a serial bus and supports position, speed, voltage and temperature readback, suitable for closed-loop control and data collection.
- The PC/Raspberry Pi controls it directly through a USB bus driver board; no extra MCU firmware is needed.
- Powered by 7–12V into the bus driver board (servos are 6V class); make sure it shares a common ground with the driver board.
- Suited to training pipelines that need joint feedback, such as SO-ARM101 and LeRobot.
PWM version highlights
- Uses PTK 7452 MG-D digital servos (333 Hz, 500–2500 µs); 50 Hz analog servos such as the SG90 cannot be used as drop-in replacements.
- Servos are rated 4.5 kg·cm@7.4V; this solution runs at 5V/3A, giving about 2.8–3 kg·cm of actual torque.
- The ESP32-S3 generates the 8 PWM channels; the host only needs to send commands over USB serial at 115200.
- No position feedback: angles, temperature and voltage cannot be read, and stall/step loss cannot be detected.
- Left and right hands share the same set of channels; each finger's servo pair uses odd channels on the right and even channels on the left, and the index finger is always CH1/2.
- Firmware must be flashed; the repository provides a prebuilt bin, and ESP-IDF can also be used to build it.
- Suited to standalone demos, gesture interaction and quick web/desktop start; not suited to feedback-dependent LeRobot training.