Skip to main content

A pure-Python Anki Cozmo communication library.

Project description


PyCozmo is a pure-Python Anki Cozmo communication library. It allows controlling a Cozmo robot directly, without having to go through a mobile device, running the Cozmo app.

The library is loosely based on the Anki Cozmo Python SDK and the cozmoclad ("C-Like Abstract Data") library.

This project is a tool for exploring the hardware and software of Anki Cozmo. It is unstable and heavily under development.


Basic mode:

import time
import pycozmo

def pycozmo_program(cli):
    pkt = pycozmo.protocol_encoder.SetHeadAngle(angle_rad=0.6)


Advanced mode:

import time
import pycozmo

cli = pycozmo.Client()

pkt = pycozmo.protocol_encoder.DriveWheels(lwheel_speed_mmps=50.0, rwheel_speed_mmps=50.0) 
pkt = pycozmo.protocol_encoder.StopAllMotors()





Robot Support


  • Camera - supported
  • Cliff sensor - supported
  • Accelerometers - supported
  • Gyro - supported
  • Battery voltage - supported
  • Cube battery voltage - supported
  • Cube accelerometers - supported


  • Wheel motors - supported
  • Head motor - supported
  • Lift motor - supported
  • Backpack LEDs - supported
  • IR LED - supported
  • OLED display - work in progress
  • Speaker - work in progress
  • Cube LEDs - supported


  • Wi-Fi AP - supported
  • Bluetooth LE - supported


  • NVRAM - supported
  • Firmware update - supported


  • Animations - work in progress

Connecting to Cozmo over Wi-Fi

A Wi-Fi connection needs to be established with Cozmo before using PyCozmo applications.

  1. Wake up Cozmo by placing it on the charging platform
  2. Make Cozmo display it's Wi-Fi PSK by rising and lowering its lift
  3. Scan for Cozmo's Wi-Fi SSID (depends on the OS)
  4. Connect using Cozmo's Wi-Fi PSK (depends on the OS)

PyCozmo vs. the Cozmo SDK

A Cozmo SDK application (aka "game") acts as a client to the Cozmo app (aka "engine") that runs on a mobile device. The low-level communication happens over USB and is handled by the cozmoclad library.

In contrast, an application using PyCozmo basically replaces the Cozmo app and acts as the "engine". PyCozmo handles the low-level UDP communication with Cozmo.

+------------------+                     +------------------+                     +------------------+
|     SDK app      |      Cozmo SDK      |    Cozmo app     |       PyCozmo       |      Cozmo       |
|      "game"      |      cozmoclad      |     "engine"     |                     |     "robot"      |
|                  | ------------------> |   Wi-Fi client   | ------------------> |     Wi-Fi AP     |
|                  |         USB         |    UDP client    |      UDP/Wi-Fi      |    UDP Server    |
+------------------+                     +------------------+                     +------------------+


  • some high-level Cozmo SDK features are implemented in the Cozmo app and have no equivalent in PyCozmo, today:
    • personality engine
    • behaviors
    • motion detection
    • face detection
    • facial expression estimation
    • text-to-speech
    • songs
  • there is no Wi-Fi control. The library assumes a Wi-Fi connection to Cozmo, established in advance.
  • frame retransmission is not implemented
  • transmission of multiple packets in a single frame is not implemented


  • Python 3.5.4
  • Pillow 6.0.0 - Python image library
  • FlatBuffers - serialization library
  • dpkt - TCP/IP packet parsing library


Using pip:

pip install pycozmo

From source:

git clone
cd pycozmo
python install


Bug reports and patches should be sent via GitHub:

Anki Robot Discord server, channel #cozmo:

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

pycozmo-0.5.0.tar.gz (65.6 kB view hashes)

Uploaded Source

Built Distribution

pycozmo-0.5.0-py3-none-any.whl (81.2 kB view hashes)

Uploaded Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page