Comment by schroeding

Yeah, it needs a "Makrofon" (very loud, high pressure signal horn) which it then can use as a "Achtungssignal" (signal demanding the attention of nearby people) to announce its departure! :D

With the power of compound words, you can combine it to "Achtungssignalmakrofon" (a Makrofon which is used to give Achtungssignale), add the information that it's small, "Achtungssignalminiaturmakrofon" (a small Achtungssignalmakrofon)! :P

You could even add the trash train information:

"Miniaturmüllzugachtungssignalminiaturmakrofon".

(Small but loud high-pressure horn signal demanding the attention of nearby people on a small trash train)