Phnx_Io_Ros

From package 'phnx_io_ros'

Files

• phnx_io_ros ./phnx_io_ros/src/phnx_io_ros.cpp
• gz_io_ros ./gz_io_ros/src/gz_io_ros.cpp

Summary

Interface packages for Project Phoenix. Each of these is designed to allow the ROS aspect of Phoenix to interface with either our simulation environment or the physical kart.

phnx_io_ros

Interface between ROS and the CAN bus. Handles receiving sensor data and also processing commands to control actuators.

Topics

Publishes

• /odom_can : Odom messages containing data from the CAN bus.

Subscribes

• /robot/ack_vel: AckermannDrive commands to control vehicle. These are passed through a PID loop and then sent to the CAN bus.
• /odom: Filtered odom values to provide better feedback to the PID loop.

Params

• port_search_pattern: The string pattern to look for when looking for a teensy device. This can be either a top level /dev/ttyACM* or the serial devices id as found in /dev/serial/by-id. By default, phnx_io_ros will use /dev/serial/by-id/usb-Teensyduino_USB_Serial* which should point to a Teensy serial monitor if plugged in. This can be by USB, or UART.
• baud_rate: Baud rate to use when connecting to a Teensy.
• motor_scale: Percent of max motor power to scale the output by, in 0-1 range.

gz_io_ros

This package acts as a fake for phnx_io_ros and allows the ROS aspect of Phoenix to interface with Ignition Gazebo, which runs our simulation environment. This packages primary function is to take in odom coming from the simulation and twist values from ROS and convert those into AckermannDrive messages to be logged with 'data_logger'

Topics

Publishes

• /odom_ack: AckermannDrive messages that contain the current steering, speed and throttle/brake percentage. Steering values and speed are stored in their respective fields; however, the acceleration field stores either the current braking percentage or current throttle percentage depending on the received twist message. Note that the steering_angle_velocity and jerk fields are unused.

Subscribes

• /odom: Odom data coming from the simulation
• /robot/cmd_vel: Twist data coming from the controller

Params

• wheel_base: Wheelbase of the kart, it should match both sim and real life

Misc

see the design for more info

wb_io_ros

This package contains a webots plugin that simulates the phoenix can bus, like gz_io_ros. This bridges any webots sensors that have no default plugins, and also exposes an interface for the actuation of AckermannDrive messages. See the tutorial for an example on how to use this: tutorial.

Topics

Publishes

• /odom_can: Encoder data from webots

Subscribes

• /ack_vel: AckermannDrive commands to actuate