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Asyncio driver for ODrive V3.6

Command ODrive over CAN with a simple interface.

Source code: https://gitlab.com/roxautomation/components/odrive-can

Documentation: https://roxautomation.gitlab.io/components/odrive-can

Features

  • designed to work with asyncio
  • implements full odrive can protocol.
  • includes OdriveMock class for device simulation
  • cli tools for message inspection, backup and demo's.

Installation

pip install odrive-can

Basic usage

import asyncio
from odrive_can import ODriveCAN, CanMsg
from odrive_can.tools import UDP_Client

AXIS_ID = 0
INTERFACE = "vcan0"
SETPOINT = 50

udp = UDP_Client()  # send data to UDP server for plotting


def feedback_callback_fcn(msg: CanMsg, caller: ODriveCAN):
    """called on position estimate"""
    print(msg)
    udp.send(msg.data)


async def main():
    """connect to odrive"""
    drv = ODriveCAN(axis_id=AXIS_ID, interface=INTERFACE)

    # set up callback (optional)
    drv.feedback_callback = feedback_callback_fcn

    # start
    await drv.start()

    # check errors (raises exception if any)
    drv.check_errors()

    # set controller mode
    drv.set_controller_mode("POSITION_CONTROL", "POS_FILTER")

    # reset encoder
    drv.set_linear_count(0)

    # set axis state
    await drv.set_axis_state("CLOSED_LOOP_CONTROL")

    # set position gain
    drv.set_pos_gain(3.0)

    for _ in range(2):
        # setpoint
        drv.set_input_pos(SETPOINT)
        await asyncio.sleep(5.0)
        drv.set_input_pos(-SETPOINT)
        await asyncio.sleep(5.0)

    drv.set_input_pos(0.0)


asyncio.run(main())

CLI interface

Usage: odrive_can [OPTIONS] COMMAND [ARGS]...

Options:
--help  Show this message and exit.

Commands:
backup   Backup config to config folder
demo     demonstration of control modes
info     Print package info
inspect  Inspect and decode ODrive CAN messages
mock     Mock ODrive CAN interface

Using virtual devices

  1. create a virtual can adapter (see docs)
  2. in first terminal run odrive_can mock
  3. in second terminal run odrive_can inspect vcan0

Position control demo

odrive_can demo position --interface vcan0

Live plotting data

Demo scripts send data as json to udp://localhost:5005 . This data can be visualized with plotjuggler

(sender code is found in tools.UDP_Client)

Development

Virtual environment

create virtual envrionment with make venv

Devcontainer

  • docker folder contains devcontainer environment.
  • .devcontainer is VSCode devcontainer environment

Support

commercial support is available through www.roxautomation.com