Somewhere in Europe, I think Italy, has a great garbage collection system where the garbage is thrown into bins in the street that deep into chutes underground where there's a network of tunnels to collect the trash. From an outside perspective this seems fairly simple to upgrade into an automated system. The chutes could have door locks installed to hold the trash, then install train rails in the underground tunnels, and when a cart stops by a section the door is unlocked and the trash falls into the cart. You can also have a sensor in the chute that detects if there's trash there so the cart can continue without stopping if a threshold isn't met. The cart would also have a fill sensor so it knows when to return. This same system would better used for garbage and recycling on the same line, just separated by different round trips.
The system at Roosevelt Island is a success, and yet that never caught on.