An open quadruped robot

Four paws.
A world of curiosity.

Meet Szarik. A robot to build, understand
and discover the world with.

Explore Szarik

A hands-on project in development. Build cost and time are still being established.
For curious makers comfortable learning mechanics, electronics and code.

Small robot. Big learning curve.

Made to move.
Built to understand.

If you can write software but have never made a motor move, this is a place to start. Szarik connects printed parts, electronics and code in one project you can take apart.

4legs
12actuated joints
Pi 5onboard computer
3Dprinted structure

The hero is a rendered motion and conversation demo. Physical performance remains work in progress.

From the workbench

Real parts.
Real progress.

Before the renders came copper wire, printed parts and plenty of things that didn’t fit. A few moments from the build diary.

Printed belt tensioner with brass inserts and screws on the workbench

From printing to designing.

A belt tensioner made for this robot. By July, the project was drawing its own parts.

Assembled black actuator on the workbench

The second actuator.

Consistent resistance readings—and a rotor that still rubbed slightly. The difficult bits are part of the story.

The first printed leg mounted on its test stand

One leg. Three actuators.

On a stand, with the feet clear of the floor. A way to learn one joint at a time.

Read the build diary

Inside every joint

A little motor.
A lot to discover.

Twelve actuators make the robot move. Start with one: a magnetic motor, a planetary gearbox and parts you can print yourself.

The Szarik actuator

Built layer by layer.

Assembled black actuator CAD render

Printed mechanics. Real metal hardware.

6:1

Planetary reduction.

Six motor turns.
One output turn.

Rotor cup with magnets lining its inner edge42

Rotor magnets.

Alternating north and south.

Three planet gears and the output carrier

A shared job

Three planets.
One output.

The planet gears travel around the sun gear, inside a fixed ring.

From the outside in

Every part has a purpose.

Simplified assembled actuator

A simplified CAD view of the assembled actuator.

Design facts, not rated performance. Torque, efficiency and thermal limits still need measurement.

Make something you can understand

Start with a part.
Think in systems.

A robot brings the whole stack together. Follow one question from the workbench all the way to the code.

01

Make the mechanics.

Printed housings and gears meet bearings, magnets, copper and fasteners. Learn why a part that looks right in CAD can still need another print.

Explore the actuator →
02

Connect the electronics.

Each joint has its own ERAD 2.1 driver and magnetic encoder. A spine board joins the twelve joints to the Raspberry Pi.

See the architecture →
03

Bring it into software.

Rust handles the core control logic. Python drives experiments and simulation. The operator console makes the state visible.

Meet the software →

A few things we know.

Actuation
12 joints · 3 per leg
Joint drive
6:1 planetary · ERAD 2.1
Rotor sensing
14-bit AS5048A encoder
Computer
Raspberry Pi 5
Joint communication
ESP-NOW via the spine board
Mass, runtime & rated torque
Not published as verified measurements

See what the software sees

More than
a moving machine.

The operator console shows the robot’s state, telemetry and configuration. It’s one more way to turn “why did it do that?” into something you can investigate.

Screenshots from the project’s operator console. This website does not connect to or control a robot.

Operator console showing joint telemetry and robot state
The operator console · telemetry view

Curiosity, encouraged

Learn the why.
Then change the how.

No robotics background required to start reading. Bring your programming experience—and a willingness to meet a few new ideas.

Why a planetary gearbox?

A gearbox trades rotational speed for turning force, called torque. Here, the motor turns six times for one output turn. The three planet gears share the load as they travel around the central sun gear, inside the fixed ring.

What does the encoder measure?

An encoder reads the rotor’s angle. This actuator uses a 14-bit magnetic sensor: 16,384 counts across a full turn. That describes resolution—how finely it reports position—not a guarantee of accuracy under load.

Why begin in simulation?

Simulation lets you try control ideas against a model before working with a physical machine. Szarik uses MuJoCo. A useful simulated motion is a starting point; contact, friction and real mechanical tolerances still have to be checked on hardware.

Work in progress · 5 November 2026

There is still a lot to learn.

The complete build cost and repeatable build time are still open. Actuator performance needs bench measurements. The hero shows a scripted rendered demonstration, not recorded physical walking or live recognition.