Quaddle | The Most Versatile Palm-Sized AI Robot

Bringing advanced mobility, AI, and an open-source platform together in one compact package—to empower your creativity.

Meet the Petoi Quaddle Family

Designed to be built and rebuilt via snap-fits.
Just 4 screws. Ready in minutes. Walks for hours.

Walks, does tricks, and codes in Block/Python/C++.

Builder, plus AI conversation and Learn & Replay.

Buddy, plus gesture, light, and infrared sensors.

Legs Reinvented: Mechanical Intelligence

An ingenious mechanism allows a single motor to drive both the shoulder and knee. By replacing extra actuators with smart mechanics, Quaddle cuts costs and extends battery life while delivering agility that rivals—and in some ways surpasses—that of far more complex robots.

🔊 Sound On!

Watch this 2-minute video to experience Quaddle's AI dialogue and real footstep rhythms in action!

World's First 4-Servo Omnidirectional Robot Dog

Trotting, gliding, sideways, and crisp in-place spins—redefining what's possible without piling on joints and actuators.

Goes Further than You'd Imagine

Swap the foot tips to conquer land, water, and gravity.

Build tomorrow, today.
Your robotics journey starts here.

"Quaddle paddles in the water" is for proof of concept only. Quaddle isn't waterproof. Do not try it at home. Different foot tips are not included but can be 3D-printed.

Learn & Replay Your Trick

Physically guide Quaddle through any movement — no code or app needed. Just tap to record and replay via its feedback servos.

* Available on Buddy and Scout

One Robot. Endless Skills.

Share your own moves with the OpenCat community.
The wilder, the better.

Be The First in Line

Join 30,000+ Petoi robot owners — get early access to our August 2026 Kickstarter launch.

Your Desk Just Got a New Resident

Most robots wow you for a day and collect dust by the weekend. Quaddle talks back, reacts to your touch, and keeps surprising you.

Chat with It

Open-domain AI conversation — ask it almost anything (Buddy & Scout).

Touch It

Tap Quaddle, and it reacts with movements and expressions.

Control It

Free mobile app to control Quaddle with built-in skills and customize commands.

Make It Yours

LEGO-compatible body shell — snap on any brick to personalize the look.

It Wants to Play with You

It reacts, it plays, it keeps surprising you — this isn't a one-trick robot.

Quaddle Scout with Sensing

Quaddle Scout is the most advanced model, capable of sensing light and objects and detecting gestures. Compatible with AI vision module.

* You can upgrade from Buddy or Builder by adding the Sense Core.

From One Robot to Many

Transform Quaddle into entirely new robots—from bipeds to Mecanum-wheel rovers—with 3D-printed parts and the OpenCat platform. Prototype, iterate, and explore AI robotics—no big lab required.

Try It Before It Arrives

Coming soon — control and interact with Quaddle in our free web simulator — no installation, works on mobile.

Test gaits and custom moves in the simulator before running them on hardware.

Be The First in Line

Join 30,000+ Petoi robot owners — get early access to our August 2026 Kickstarter launch.

A Tinkerlab Inside a Micro-Robot

We packed a powerhouse of multi-core processors and peripherals into a palm-sized frame for ultimate hacking and tinkering.

Code It Your Way — or Don't Code at All

Drag-and-drop blocks on iPad or Android tablet. Graduate to Python when you're ready. AI helps you along the way.

Built on OpenCat — the open-source quadruped platform cited in 20+ academic papers. Block coding → Python → MicroPython → C++ (Arduino IDE) → ROS. Free curricula included.

A Physical AI Platform You Can Extend

Plug things in. Make it yours.

🔌 Unlimited development over USB
🚶 Up to 2 hours of nonstop walking
🔋 Swappable battery for extended sessions

Arduino/ESP32 module support

Quaddle has a variety of programmable peripherals. Expand its sensing and capabilities with plug-in modules.

Raspberry Pi Zero & ROS-ready

Built-in Pi Zero socket on all models; run computer vision or any Pi project you have in mind (Pi not included).

Be The First in Line

Join 30,000+ Petoi robot owners — get early access to our August 2026 Kickstarter launch.

The Story of Petoi — the Builder of Quaddle

Dr. Rongzhong Li founded Petoi in his dorm lab in 2016. After his prototype OpenCat robot video went viral, he wanted to ensure the robot could truly work in more users' hands, rather than keep posting fancy demos branded as open-source that only experts could reproduce.

Quaddle is the next robot from that same team, on the same platform, backed by the same track record shown above. Dr. Li still handles a quarter of customer support directly.

The Story of Petoi — the Builder of Quaddle

Built on a Proven Open-Source Robotics Platform

Quaddle runs on OpenCat — GitHub's most starred open-source quadruped robot project since 2018.

Continuously iterating: Nybble became Nybble Q, Bittle became Bittle X and Bittle X+Arm.
Long-term support for the earliest model.
Cited in 20+ academic papers: Used in university research labs and K-12 classrooms worldwide.
Market Pioneer: Validated the market for maker-level, servo-driven quadruped robot dogs.