Bittle: A flexible and small bionic mechanical dog, the best little assistant for learning and living

Who can resist the temptation of a cute kitten?

Although kittens are glamarous on the surface, they are always secretly ruining your favourite couch behind your back!

Today I will introduce to you a pet that can accompany the owner while obediently and does not bite the chair: Bittle

Today, I’ll introduce to you a pet that can not only keep you accompany, but also remain obedient and acquiescent; the Bittle.

The Bittle is a miniature four-legged walking robot developed by Petoi. With the size of a palm, itmoves like a real animal.

Compared to the US$74,000 Boston Dynamics spot, the price of this small mechanical dog is only a touch above US$300. making it affordable for the masses!

Bittle is not a simple toy. It is very powerful, with each part consisting of high-strength injection molding plastic. It has also gone through dozens of iterations of 3D printing. Even if someone stepped on its body, he could still get back up and stand strong..

The flexibility is also very good, and the springs of the limbs can play a certain buffering effect. With highly flexible joints, the springs of its limbs also plays a certain buffering effect.

Climb up stairs with its four feets proficiently, and watch it automatically straighten itself after falling off a slope!

After purchasing Bittle, customers will receive a kit that includes a box, 1 Bittle body, 1 remote control, 1 spare servo, 1 calibrator, 1 USB downloader and 1 data cable.

If you feel that just owning a Bittle is monotonous, you can also purchase the Bittle  Sensor Pack, an expansion accessory package comprising of plug-and-play Grove electronic modules. It can bring a brand new perception ability to Bittle.

Simultaneously, TinkerGen, Petoi’s partner company, has compiled exquisite free courses for Bittle. Users can quickly get started with open-source hardware and software programming according to the courses, so as to indulge in the joy of learning.

Technical Parameters

Bittle’s size is 200x110x110 mm.It weighs less than 280 grams, and can withstand a maximum load of 450 grams. The maximum walking speed of the robot is approximately two body lengths per second. Bittle can memorize a variety of behavior patterns and perform various actions under the direct remote control of the user. The small battery can last about an hour of active work.

Bittle is mainly composed of five parts: body frame, servo,  control board, driver software and battery.

Body frame

Bittle’s body frame is made from a high-strength injection molding process. For simplicity and beauty, most body parts are symmetrical and it uses only a few screws to keep its body intact.


The Bittle uses 9 P1S servo motors, which is a custom high-quality servo motor with a controllable angle of 270 degrees. Eight of them are used for the walking joints and one is used for head rotation. A spare servo motor is also provided for replacement.

Control board

Bittle coordinates all movement patterns through a customized Arduino board, with onboard 16 PWM servo pins and an infrared receiver. t also has multiple communication ports to connect to other devices, such as the Raspberry Pi, which makes it a mature AI robot.

Driver Software

Bittle is compatible with Windows, macOS and Android. You can also remotely control it by installing the wireless module and using various auxiliary softwares.

Bittle’s code has been open-sourced on GitHub. It has almost three thousand lines of Arduino code. It defines the smallest data structure and algorithm for performing the quadrupedal movements. Furthermore, Petoi also provides sample command programs and parsers in Python so that customers can send instructions from other devices. The code has been run on thousands of small quadruped robots.


The cell is a lithium-ion battery pack with a built-in charging and protection circuit. It can slide into the track under Bittle and adjust its center of gravity. It can provide Bittle with at least one hour of continuous walking power, with RGB LED to indicate its battery status.

About the founder of Petoi: Dr Li Rongzhong from China

Dr Li Rongzhong graduated from the Department of Physics, Nanjing University, China. He then received a master’s degree in computer science and a doctorate in physics from Wake Forest University in the United States.

Dr Li founded Petoi in 2017, making it a full-time business in 2018, and then started to develop their first bionic quadruped walking robot series project for the Petoi team-OpenCat crowdfunding. They successfully raised US$250,000, with users from more than 50 countries around the world.

In July 2019, Li Rongzhong returned to Shenzhen from the United States. Dr. Li brought back the OpenCat project and its first product, Nybble, while Bittle, which we are talking about today, is Nybble’s brother,the second series of OpenCat products.

While many people are imitating Boston Dynamics’ expensive quadruped robots, OpenCat is the world’s first robotic platform that uses consumer-grade steering gear to achieve quadruped gait and mass production. Currently, Bittle is available in Seeed’s store, you can buy it here.

Here are some links to related materials:

Petoi website:

Petoi community:

Petoi help documentation: -help-en/bittle

Bittle course:

Bittle Sensor Pack:

TinkerGen Bittle introduction page:

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August 2021