$150 BILL OF MATERIALS
Consumer Maker Hardware
Microcontroller: ESP32-S3 or Raspberry Pi RP2040 ($6).
Actuators: 4–6x Feetech STS3215 magnetic encoder serial bus servos ($60–$80).
Power: 2S LiPo (7.4V) or 5V USB-C PD ($15).
Chassis: 3D-printed PETG / PLA / TPU ($10).
Camera: USB UVC webcam or ESP32-CAM ($12).
Total BOM: ~$150. Accessible for makers, students, and children.
FAST SPINE FIRMWARE
200–500 Hz Spline Interpolator
The edge MCU fast spine runs a deterministic hardware timer interrupt. It receives receding-horizon action chunks (30–50 waypoints) from the host brain over UART/WebSerial.
Evaluates smooth cubic Hermite spline trajectories locally and drives servos over 1 Mbps half-duplex UART bus with zero communication jitter.
Includes hardware watchdog: brings motors to rest if packets cease for > 100ms.
ZERO-INSTALL WEBSERIAL
Browser Direct-to-MCU Bridge
Using the W3C WebSerial API, any browser running on a Chromebook, Mac, or Windows PC can connect directly to the robot's USB-CDC port without installing drivers, ROS 2, or Linux.
Deploy trained neural policies, send action chunks, inspect live proprioception, and verify cryptographic receipts directly in the web browser.
Read the Developer Blueprint ↗