Szarik
From printing to designing.
A belt tensioner made for this robot. By July, the project was drawing its own parts.
An open quadruped robot
Four paws.
A world of curiosity.
Meet Szarik. A robot to build, understand
and discover the world with.
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.
The second actuator.
Consistent resistance readings—and a rotor that still rubbed slightly. The difficult bits are part of the story.
One leg. Three actuators.
On a stand, with the feet clear of the floor. A way to learn one joint at a time.
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.
Printed mechanics. Real metal hardware.
Planetary reduction.
Six motor turns.
One output turn.
42Rotor magnets.
Alternating north and south.
A shared job
Three planets.
One output.
The planet gears travel around the sun gear, inside a fixed ring.
Mechanical pieces.
Reference assembly, counting every magnet, screw and insert separately. Electronics and wiring are additional.
See the breakdown
- Printed parts
- 11
- Magnets · 42 rotor + 1 encoder
- 43
- Threaded inserts
- 28
- Screws
- 15
- Steel pins
- 10
- Metal magnet-holder sheets
- 12
- Bearings
- 4
- Wound stator
- 1
Reference mechanical assembly. The wound stator counts as one purchased assembly. Electronics, cables, connectors and robot mounting bolts are additional; later revisions can change the total. Four cover screws have provisional specifications.
From filament to parts.
Estimated printing time for one actuator, across three plates.
Printer and settings
Reference print package 827, sliced for a Bambu Lab H2S with a 0.4 mm nozzle and PETG Basic. Total estimated time: 16 h 8 min 26 s. Individual parts use their saved print settings. Assembly, cooling, support removal and reprints take additional time.
Filament for one.
PETG for the printed parts and supports, from the same sliced package.
What this weight includes
The three plates use an estimated 238.97 g, 6.41 g and 9.94 g: 255.32 g in total, including supports. This is material consumption, not the weight of the assembled actuator. Complete actuator weight still needs a scale measurement.
From the outside in
Every part has a purpose.
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.
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 →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 →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.
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.