- Open source – Bittle is an open platform powered by OpenCat to fuse multiple makers’ gadgets into one organic system.
- Arduino-powered extensibility – with our customized Arduino board coordinating all instinctive and sophisticated movements, you can clip on various sensors to bring in perception.
- Artificial intelligence – one could also inject artificial intelligence capabilities by mounting a Raspberry Pi or other AI chips through wired/wireless connections.
* Use the optional intelligent camera module mounted on Bittle’s mouth to recognize and follow the object
* Self-righting after falling from a slope (triggered by an infrared remote)
* Climbing up a step under realtime instructions sent through Bluetooth
- Bittle battery
- Bittle shell
- NyBoard V1
- Bluetooth dongle
- Wifi dongle
- 10x P1S servos
Bittle is a palm-sized robot that moves with four legs rather than wheels. Legged motion gives it more freedom to navigate unstructured terrains, and expresses the joy of life whenever it moves. Such dynamic maneuverability was only seen on a few luxury robots from the best labs or tycoon companies previously, such as Boston Dynamics Spot or Sony Aibo. We came up with a grassroots solution to simplify the system to make it affordable and mass-producible.
Bittle consists of five major components: body frame, actuator, electronics, battery, and the software to coordinate all the hardware to perform varied tasks.
We designed Bittle’s interlocking frame as a 3D puzzle with very few screws involved. Most body parts are symmetric for simplicity and aesthetics.
It’s a pleasure to assemble and disassemble Bittle for teaching or maintenance. On average, it takes about one hour to put together the body from scratch.
Build a Robot Dog on Your own!
Each piece has gone through tens of iterations with 3D printing. We then use high strength injection-molded plastic to provide the best protection from collision and dust (it’s NOT waterproof!). In the stress tests, the assembled robot can take an adult’s stepping without breaking any components (do NOT try this at home!).
We also designed Bittle to be soft. Besides the elasticity of the material, the spring-loaded upper legs flatten the shock on joint servos to protect their gears. Bittle usually survives regular collisions. In the extreme cases, it will disintegrate at the designated “weak link in the chain”, which is easy and cheap to reinstall or replace.
We designed the frame to be compatible with most 9g servos. You could order the “Bittle Shell” perk alone to compile your spare servos into a beautiful action figure!
We visited several servo manufacturers and iterated many times to find the optimized parameters. It will be model P1S, a slim, fast servo with a controllable angle of 270 degrees.
We use nine P1S servos to actuate Bittle. Eight of them are for walking joints, and one is for head panning. We will also include one spare servo for replacement, as brushed motors are consumable after a certain period of wearing. You may order the “Bittle Servo Set” perk if you expect to use Bittle intensively for teaching or researching.
Bittle is driven by NyBoard V1, a customized Arduino board with rich peripherals. We fully utilized the chip of a regular Arduino Uno to coordinate sophisticated motions. The board can drive at least 12 PWM servos, and an IMU (Inertial Measurement Unit) is used for balancing. It stores “muscle memory” and detects body status (orientation and acceleration) for balancing. We provide an infrared remote to trigger basic movements. The board also listens to string commands from the serial port, such as “walk”, “sit”, or more detailed instructions for individual joints.
* NyBoard V1
NyBoard V1 is a revision of NyBoard V0 that has been driving 2000 Nybbles all over the world. We continue to provide a 2×5 socket on NyBoard V1 for mounting Raspberry Pi. It powers the Pi and communicates with it through the serial or I2C network. The Pi gives Bittle the ability to analyze more sensory data, get connected to the Internet, and make decisions by itself. Due to Bittle’s small size, it best fits Pi Zero and Pi 3A+. For larger Pi models, you will need to tilt the Pi and 3D print some supporting structures.
* Raspberry Pi 3 A+ and Pi camera on Bittle. Note that the Pi and camera are not included in the standard product package.
Thanks to the Arduino and Raspberry Pi community, you can find many customization ideas for Bittle. There are four Seeed Grove sockets on NyBoard V1 for extensible modules. To make installation easier, we designed Bittle’s head as a clip to bite on those modules. That explains why we created a dog out of OpenCat this time. There’s also a screw hole inside Bittle’s head for fixing additional modules.
* Extensible Modules (not included in the standard kit)
We developed a Bluetooth dongle for wirelessly uploading codes and controlling Bittle from PC or smartphone Apps. We also developed a WiFi dongle for wirelessly communicating with Bittle. You can play with Bittle without messing around with cables. Wireless is also essential when you are studying balancing related motion planning. You can even utilize the computational power of a remote “brain” without being constrained by Bittle’s size and cargo capacity. The dongles are compatible with our previous Nybble model.
* Bluetooth and WiFi Dongles
We designed a Li-ion battery pack with a built-in charging and protection circuit. It can slide into the track underneath Bittle and tune its center of mass. It can power Bittle for at least one hour of continuous walking. It also has an RGB LED to indicate the battery’s status.
* Li-ion battery with onboard charging and protection circuit
With the slide-in installation mechanism and an anti-reverse plug, it’s not too hard to switch batteries. You may order extra batteries for uninterrupted researching or playing. With some reconfiguration, it can also power our previous Nybble models.
Powered by OpenCat, the open-source Arduino and Raspberry Pi-based robotic pet framework developed by Petoi
OpenCat has 3K Lines of Arduino codes excluding 3rd party libraries. It defines the minimal data structure and algorithms for performing quadruped motion. We also provide example commander and parser in Python so that you can send instructions from other devices. The code is already running on thousands of small quadruped robots, including many variants of OpenCat.
You can program Bittle at different levels in various coding environments, such as C in Arduino IDE and Python in the terminal. We are collaborating with TinkerGen, a STEM education company that kindly developed Codecraft (a graphical coding environment) for Bittle. They will also provide a free curriculum for you to learn programming in Codecraft and create a wide array of educational and fun projects with it!
You can code in Arduino IDE, Python, Codecraft, and many other environments
To make our community more productive, educational, and rewarding, we’ve launched an online challenge for all OpenCat users. You can find our proposed rules in this forum post and give suggestions before it officially starts. In short, we will define several tasks that can be measured quantitatively, e.g., programing Bittle to get onto the highest step. You have to both demo your solution and teach others to validate your entry. On the first day of each month, we will announce the world’s record-breaker and gift a free Bittle or Nybble to the winner!
Bittle is 20cm x 11cm x 11cm in dimension. It weighs less than 280g but can carry up to 450g cargo under its belly. With proper programming and calibration, It can run faster than two body lengths per second. Bittle can remember tens of instinctive motion patterns and can perform more fancy tricks with real-time instructions.
P1S servo uses a coreless motor, alloy gears, ball bearing, and plastic case. It’s 8.4V compatible, high speed, and has a controllable range of 270 degrees.
NyBoard V1 has an Atmega328P with 16MHz CPU, 2K SRAM, and 32K flash. We also added an 8K I2C EEPROM, an IMU, a servo driver for 12 PWM servos, an infrared receiver, and a buzzer. It has a 2×5 socked to mount on a Raspberry Pi.
The Bluetooth dongle is compatible with Windows, macOS, and Android. It can also work on IOS with some auxiliary software. It can be used for uploading Arduino sketch or communicating with the NyBoard. The WiFi module can host a simple WebUI and communicate with the NyBoard.
The optional intelligent camera module is our ODMed product. It integrates multiple vision recognition algorithms running on its ESP32 dual-core processor. It can return recognized human body, objects, and symbols through serial/I2C/WiFi at a rate of 25fps or 50fps. It can even stream video through WiFi. We will also include a deck of symbol cards. You can refer to this link for more information.
Note: Bittle is not a toy for small kids. We recommend parental guidance to appreciate its rich content and avoid damage or injury.