What's wrong with my undetected, unresponsive Arduino Robot?
I'm pretty sure and sadly to announce you that the usb communication of your Arduino Leonardo Compatible is dead and the arduino is connecting to the computer just like an alimentation Source no more.
And since Arduino Leonardo based on The ATmega32U4 which has built-in USB communication ,so the Atmedga32U4 is dead(u-processor) too.

It's not a software matter but hardware one.