BAbout this program
1,382 stars on GitHub.
Stack-chan is a palm-sized, open-source "super-kawaii" companion robot driven by an M5Stack microcontroller and JavaScript firmware. Created by Shinya Ishikawa, Stack-chan sits on your desk, turns its head to watch you, expresses emotions on its built-in display, and responds through speech — a personality in a box you can hold in one hand.
Source: https://github.com/meganetaaan/stack-chan
The firmware is written on the Moddable SDK, a JavaScript framework for embedded systems, making the robot programmable without leaving the web development ecosystem. Behaviors — called "mods" — are composable: face expressions (happy, angry, sad), servo-driven head tracking, speech synthesis, and M5Stack unit add-on support can all be mixed and layered.
The 3D-printable enclosure is modular and supports multiple servo configurations: the default case uses SG90 or MG90S servos for pan/tilt, while a second design (RS30X series) uses higher-torque TTL servos for smoother motion. The 46-part printable set covers the main shell, bracket, feet, spacer, accessories (hat, backpack variants, Lego adapter), and servo-specific geometry for SCS0009, SG90, MG90S, and RS30X actuators.
An official M5Stack commercial version (StackChan) is also available, with the community meganetaaan fork remaining the primary open-source hardware and firmware reference.
License: Apache 2.0.
🖨 Print Files (106)
backpack_400mah.stl
backpack_640mah.stl
backpack_aaa.stl
backpack_casio_battery.stl
bracket_RS30X.stl
feet_RS30X.stl
Required Hardware
| Item | Qty | Unit Cost | Notes |
|---|---|---|---|
| M5Stack Core2 (or Basic/Fire) | 1 | $50.00 | Main controller (ESP32-based) |
| SG90 micro servo (PWM) or Feetech SCS0009 (serial) | 2 | $5.00 | Pan/tilt for head movement |
| LiPo battery 3.7V 500mAh JST-PH | 1 | $8.00 | Optional, untethered operation |
| 100µF 1206 SMD capacitor | 4 | $0.20 | PCB power filtering |
| Pin header 2x15 2.54mm | 1 | $1.00 | M5Stack stacking connector |
| Pin header 2x3 2.54mm | 2 | $0.50 | Programming/expansion |
| JST PH 2-pin connector (battery) | 1 | $0.30 | Battery socket |
| JST PH 4-pin connector (servo) | 2 | $0.40 | Servo connectors |
| JST XH 2-pin connector (power) | 1 | $0.30 | Power input |
| IRLML6402 P-channel MOSFET | 1 | $0.50 | Power switching |
| SMD 0603 resistor assortment (1k/10k/47k/100Ω) | 1 | $5.00 | (inferred kit) PCB pull-ups & dividers |
| OS102011MA1QN1 slide switch | 1 | $1.50 | Power switch |
| TC7WH241FK or NL27WZ125 buffer IC | 1 | $1.00 | Required for serial-servo variant only |
| Custom Stack-chan PCB | 1 | $10.00 | (inferred) Order from JLCPCB/PCBWay |
| M2 fastener / mounting screws | 1 set | $5.00 | (inferred) Servo and case assembly |