Skip to content

Wiki

JOY Controller

About 4 min read

1.Introduction

2.Detection Equipment

You can take a look when the controller is not plugged in:

ls /dev/input/

Plug in the controller and take another look.

Look carefullyjs0,event15Is there more of this kind?

As shown in the figure above, for me I amjs1andevent24.

You can use the following command to confirm the device name:

cat /proc/bus/input/devices

Find in orderevent24：

3.Linux test gamepad

# Ubuntu或者Debian
sudo apt install joystick

# Fedora
sudo dnf install joystick

Then

jstest /dev/input/js1

You can toggle the joystick to test it:

4.ROS Joy node

Installjoyandjoy-linuxpackages, these two packages are two differentjoynodes.

sudo apt install ros-$ROS_DISTRO-joy
sudo apt install ros-$ROS_DISTRO-joy-linux

4.1.Joy

Start node:

ros2 run joy joy_node --ros-args -p device:=/dev/input/js1

You can see the prompt in the image indicating that it has already connected to the Xbox controller.

View topic data:

ros2 topic echo /joy

Frequency of viewing topics:

ros2 topic hz /joy --window 20

--window 20If the transient state is more accurate, it will discard the older data above,window=20 it will soon discard the old samples.

My frequency here is at 3200 Hz, which is obviously too high.

4.2.Joy_Linux

Try another package:

ros2 run joy_linux joy_linux_node --ros-args \
  -p dev:=/dev/input/js1

You can see the prompt in the image indicating that it has already connected to the Xbox controller.

View topic data:

ros2 topic echo /joy

Frequency of viewing topics:

ros2 topic hz /joy --window 20

In this package, the frequency is stationary at 20 Hz, and after the handle becomes active, it is at 500 Hz.

ros2 run joy_linux joy_linux_node --ros-args \
  -p dev:=/dev/input/js1 \
  -p autorepeat_rate:=50.0 \
  -p coalesce_interval:=0.01

After using the above command, the frequency dropped to 50-100 Hz, which is the most comfortable frequency range for ROS