Mechatronic head, 18 DOF — Noddy Chung
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Mechatronics Computer vision Swansea University, 2021–22

Mechatronic
head,
18 DOF

An original humanoid skull with eighteen degrees of freedom, built to hold a real facial expression and to follow a face across a room. I drew the mechanism, designed the electronics, printed and assembled every part, and wrote the control and vision code. It won the W Renwick prize for best software-based project of the year.

RoleProject owner, solo build
Motion18 degrees of freedom, servo driven
StackFusion 360 · SLA / FDM · 3D printing · Python · OpenCV
AwardW Renwick Best Software-Based Project
A0 general-arrangement drawing of the robot skull: front, side, top and section views with dimensions in millimetres
robot skull — general arrangement, every linkage dimensioned before a single part was printed A0 · 1:1 · mm

Drawn as a
mechanism

Eighteen axes in the volume of a skull means the linkages decide the design, not the face. Every bracket, pivot and horn was modelled and checked for travel and collision before printing, so the assembly went together once instead of four times.

Eyes — pan, tilt and lids on separate axes, gaze driven by the tracker.
Face — brow and mouth corners pull on a sprung line for expression.
Drive — PCA9685 channels from a Pi, expressions stored as angle sets.
CAD assembly render of the animatronic skull linkages
assembly render — travel checked before print
The animatronic head wired to a breadboard and servo driver on the bench
bench state — camera under the chin, 18 channels out
eighteen channels live — holding an expression, finding a face Hover for sound

It looks
back at you

A camera under the chin feeds OpenCV; the detected face position becomes a gaze target, and the eye axes chase it while the lids and brow keep the expression alive. The same interface plays canned expression sets on demand, which is what a show operator actually needs.

first time it picked a face out of the room and followed it across the bench.

What I took from it

figure motion
Believable motion is written for prompt response to the user, to achieve a smooth operation for the audience.
show control
Built as a closed loop system. Stored expressions sit in a cue stack an operator can trigger live — the way a real installation has to run.
maintainability
Printed parts, standard servos, one driver board: rebuildable by whoever inherits it.
Next: sign-translation gloves → All work chungnoddy0808@gmail.com