Petoi Doc Center

FAQ(Frequently Asked Questions)


Cannot upload sketch, sync error.

The error that occurs when uploading the sketch is shown below:
This "not in sync error" indicates a bad connection between your computer and your robot. It could be:
Usually, it can be fixed by the following checks:
  1. 1.
    Install the CH340 driver​
  2. 2.
    Use the USB cable with the data function(the one included in the kit is good).
  3. 3.
    Select the correct board (Arduino Uno) and serial port
  4. 4.
    Connect the board and the programmer in the right pin order
The above steps are covered in the Doc Center.
Of course, you can also refer to the solution in the Arduino technical forum:

What do different sounds from the board mean?

Sound type
Short melody
Power on or reboot
The program starts successfully
Short beep
During use
The program receives a command
Repetitive short melody
During use and pausing the movements
The battery is low or unconnected


How can I easily install the springs into the upper legs of Bittle?

Please check out the forum post discussing installing springs with varies tools.

I can't find the toe covers. What are the toe covers for?

The toe covers are for special experiments that require more friction. They are not required for regular walking and performance. We have removed them from the standard kit recently and you may order them as optional accessories.

Some frame structures are broken. Where can I get replacement parts?

You may contact [email protected] Show the picture of the broken pieces and explain how they broke. You may find the 3D-printable files or get a replacement directly from us.

Bittle walks very slow.

Try turning off the Gyro in the mobile app, as shown in the following picture:

Bittle cannot turn back up now.

Try turning on the Gyro in the mobile app, as shown in the following picture:

Bittle doesn't walk very stable.

  • Make sure you calibrate the joints with the included L-shaped tuner and understand the references
  • Remove the rubber toe covers
  • ​Turning off the Gyro will make slow gaits more stable

Where can I get the bone shown in Bittle's picture?

The little bone is included in the Intelligent Camera Module box and it is not being sold separately. You may download its 3D-printable file at:​

Driver for CH340 USB uploader

  • Mac:
  • Windows:

3D printable replacement parts and accessories

Can your little robot dog (Petoi) function on its own? Or, it only works with the commands I give it? Also, can it learn?

It follows your instructions via the infrared remote, smartphone app, or desktop app. It can also do random behaviors if you upload the random mode. Best of all, the program is opensource on GitHub and you have the freedom to alter any bit of it.

Can I use Codecraft/block-based coding with the basic Bittle package or do I need to purchase add-on components/modules?

Bittle can be programmed with a Scratch-like web-based IDE Codecraft. You may find some complementary materials: online help and curriculum.
Note that CodeCraft hasn't provided support for our 2.0 version. But you may roll back to the supported version within CodeCraft or through our tool.
You don't need to buy add-on components to use the basic functions in Codecraft. However, several extension functions require add-on components. If you are comfortable with coding with Arduino, you can have a much wider selection of third-party components.

If to buy the preassembled bittle does it still have to be calibrated?

Yes, you still need to use the smart phone app or Aduino IDE to fine tune the joints. It usually won't involve any installations.

If you buy the controller board alone, do you have to buy a separate software program to make it work?

Our controller board is an Arduino-compatible board specifically designed for our robots. The code is free to download on GitHub.

Does it come with a battery or do you have to buy a lithium battery?

Both Bittle kit and pre-assembled Bittle include one Lithium battery with a built-in charging circuit. You may add more spare batteries.
Will I be able to use Codecraft/block-based coding with the basic Bittle package or do I need to purchase add-on components/modules?

Could Python be used to control the robot?

You can use python to control the robot directly. The script can work either on your computer and connects to the robot wired or wirelessly.

Does Rasberry Pi require any additional components?

The robot can run with a Pi, and you can mount Pi on the robot directly.