About | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange

melodic noetic   Show EOL distros: 

Overview

The packages provides functionality to expose CAN frames from SocketCAN to a ROS Topic. Internally it uses the socketcan_interface from the ros_canopen package, as such it is capable of dealing with both normal and extended CAN frames. For more information and hardware related information see socketcan_interface.

Nodes

The functionality is offered in the form of three nodes: socketcan_bridge_node, socketcan_to_topic_node and topic_to_socketcan_node. To receive frames from and sent frames to the same CAN device, the socketcan_bridge_node needs to be used to prevent every sent message from being echoed to the receiving topic.

socketcan_bridge_node

Receives frames from SocketCAN devices and publishes these on the topic, at the same time it listens to CAN messages and sends these to SocketCAN. The frames that are sent to the CAN device are not published as received messages.

Subscribed Topics

sent_messages (can_msgs/Frame)

• Messages received here will be sent to the SocketCAN device.

Published Topics

received_messages (can_msgs/Frame)

• Frames received on the SocketCAN device are published in this topic.

Parameters

~can_device (string, default: can0)

• Name of the SocketCAN device, by default these devices are named can0 and upwards.

socketcan_to_topic_node

Publishes the frames received on the SocketCAN device to a topic.

Published Topics

received_messages (can_msgs/Frame)

• Frames received on the SocketCAN device are published in this topic.

Parameters

~can_device (string, default: can0)

• Name of the SocketCAN device, by default these devices are named can0 and upwards.

topic_to_socketcan_node

Sends CAN messages received on the topic to the SocketCAN device.

Subscribed Topics

sent_messages (can_msgs/Frame)

• Messages received here will be sent to the SocketCAN device.

Parameters

~can_device (string, default: can0)

• Name of the SocketCAN device, by default these devices are named can0 and upwards.

Remarks

Several aspects to take into account:

• Error frames from the device are also converted to a message and published on the topic. A warning is displayed for every error frame.

• The timestamp of the messages is based on ros::Time::now() at the moment the frame is read from SocketCAN.