When using Ubuntu often requires Remote Desktop connection, the most common software is VNC. VNC is an open protocol that implements a lot of clients. But after comparing the various implementations, the best is now x11vnc. This program is not only free of charge, open source, but also supports OpenGL programs. For example, rviz and other programs can also open normally.
The X11VNC is already installed by default in the xiaoqiang system image, and if you use a xiaoqiang host or mirror, you can skip the installation process directly. Just follow the instructions for accessing the service.
The installation method is described below. The following is an example of Ubuntu 14.04, if it is 16.04 and later version, you need to edit the service configuration file.
sudo apt-get install x11vnc -y
sudo x11vnc -storepasswd /etc/x11vnc.pass
Under/etc/init, create a x11vnc.conf file with the following file contents
description "xiaoqiang vnc server" start on runlevel  stop on runlevel  script exec /usr/bin/x11vnc -auth guess -capslock -forever -loop -noxdamage -repeat -rfbauth /etc/x11vnc.pass -rfbport 5900 -shared end script
sudo service x11vnc start
Download a VNC client, such as download from here
Start the client, enter target ip address
and then enter access password
Then you can connect normally.
For Ubuntu 16.04 and later, You can configure your service file according to this script
Note When the installation is complete, you may still get an error when you use rviz without plugging in the monitor. Just plug in the HDMI to VGA adapter (do not connect the monitor, just the adapter) can be turned on normal use. If you want to adjust the resolution in the same way as normal computer settings, adjust the settings inside system settings