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.
Category: Humanoids
| 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 |