Can I connect both an expansion shield and motor shield to this arduino due? If so, how?

ARM processors can also support embedded linux not just arduino. gentoo linux works really well for embedded projects. that would give you the ability to include scripting support to your projects be it a bash script or something more complex like python. or even a full apache lamp server. imagine web login to your robot and queuing timed one time or repeatable commands via crontab using phpmyadmin...its possible with an ARM processor...DFRobot really should hire a linux developer specialized in gentoo or another source based distro or a distro like slackware. they could pre compile embedded linux OS into a binary distro for their ARM boards to be downloaded. wouldnt take but a few days to put a minimalist package together.

Hi
The IO expansion shield is available since it is shown on the 3.3V compatible Device list, and if you want to find amotor shield, you need to make sure the working voltage is suitable.