Is it possible to connect Arduino sensors to the VIDI X microcomputer?

Yes, you can connect Arduino sensors that require 5V on logic pins, by using a logic level converter. . The serial communication tutorial explains how to use a 3V-5V logic level converter for this purpose.
You can also use a voltage divider along with a resistor. An example of how to use a voltage divider and a logic level converter can be found in the tutorial about the VIDI X keyboard.