Exactly.  Even the article itself describes the propulsion system as "tracks", although it likely misappropriates the trade name "caterpillar", which is a US-based heavy contruction brand name.

Apparently, there was translation involved here, and that may explain the confusion between "tracks" and "chains".  But if not, someone needs a lesson in the difference between the two; they're quite different, and "tracks" is definitely what's correct in this case, and without "caterpillar". 

Military tanks also have "tracks" for propulsion, but not the "caterpillar" kind.

Chain drive?