Sparks: Animatronic Dragon

Currently being built — not finished, and not yet worn. The earlier v3 build is archived.

Head Mechanisms

Current dragon head assembly from above, showing the eye, eyelid, jaw servo, and wiring — Current head assembly

Nine WaveShare SC09 small bus servos drive the head. One moves the nose up and down. Two drive the top and bottom eyelids separately. One drives the jaw.

Two servos move the eyeballs on X and Y through string. Two move the tongue on X and Y through string. A metal-wire control rod, driven by one more servo, moves the tongue forward and back.

Eyelids and eyeballs in motion on the dragon head — Eyelids and eyeballs in motion

Neck

The neck is the same design as v3: six servos, same axes of motion, carried over from the previous version. The neck servos are WaveShare ST3215 20 kg bus servos. Head and neck together are 15 servos — every main axis currently designed.

Planned Additions

Three more servos are planned. None of them are built or prototyped yet. One would extend wings that poke out of a backpack the dragon is housed in. Two would drive a tail that sticks out the bottom of the backpack. That would bring the total to 18.

Control System

The main processor is now a Raspberry Pi 5, upgraded for onboard AI/compute and camera control. Both eyeballs are hollowed out internally to fit a small Raspberry Pi camera module in each eye.

The Pi 5 connects to a WaveShare bus servo controller board. All head SC09s and neck ST3215s daisy-chain off a single signal wire on that board. A WaveShare voltage step-down regulator sits inline so every servo on the shared bus gets the correct voltage.