Going back to my discussion about leaving Taiwan…
Does anyone have experience with automatic litter box in Taiwan? I remember when I was in high school, we were out of town a lot and often are just gone for a few days, so we would set the auto feeder and auto litter box and it was good for at least that long…
Are they worth the money?
I’ve had a friend or two recommend auto-litter boxes before. Said it saved them a lot of time. They’re really pricey though and they do take up a large chunk of space, so do consider that as well. I can’t really say much beyond that.
As for auto-feeders, they’re great! We’ve got auto-feeders that dispense kibble during the day. At night, the cats eat wet food which we prep ourselves. Pretty convenient to have if you’re out most of the day. I’m not sure how long you’re planning to be out for, but you’ll probably need to ask a friend/family member to swing by to help you refill the feeders if you’re out of town for quite a bit.
if it is longer than 1 week, I have a fair amount of confidence your skill set, and mind set, can build something better and cheaper than what is available commercially.
The commercial ones have a motion sensor to sense when the cat is doing its business, then it waits about 10 minutes before activating the scooping mechanism. The problem is I have basically no experience in motion control, raspberry pi, arduino, etc… so it’s going to take some time and money for me to figure it out. It might actually be cheaper to simply buy a ready made product…
If I’m going to mess around with arduino then saving money to get an automatic litter box is the last thing I should be concerned about… The foremost reason would be to learn the system and use that skill to do something else.
I suppose my point was less so that the auto timers and sensing is the issue and moreso that where the auto system dumps its shit is a bigger problem. long term. Raised systems are easy, but will stink.
You could do something as simple as this:
Some simple logic could be to look for motion, then wait for a couple of minutes with no motion, then power a relay to start raking sand.
Ok, now the challenge is to figure out a way to make the scoop itself, keeping in mind that cats are going to shit all over it, so it can’t have any nooks or crannies.
Found this:
And this:
Maybe you can come up with a smarter way to do this?
Smarter, yes, cheaper, hell no.
The first video is how Litter Maid works I think. And the litter has to clump well, if you got those litters that don’t clump well, they just leave a bigger mess.
I find that sometimes litter can take the better part of a day to clump after the cat did its business… at least in Taiwan where humidity is always high.
If you are willing to spend a bit of time and effort, you can train your cats to go in the human toilet. Then all you need to do is buy an automatic flusher which doesn’t cost very much.
The upside of this is if their water bowl runs out of water or falls over or whatever - they still have a water source available.
so how do you train cats to use the toilet? Can you train cats to do that? I always thought you can’t train cats, cat trains you.
see food production machinery and think sifting. it is a cheap sollution without those fancy wasteful plastic UFO type price gouges 
I’ve heard toilet training cats is actually not good for sea life (cats have parasites that don’t get filtered out of human waste management) and also not great for your cat (bad for their mental health if they don’t cover their poop — that’s an important step to make them confident others won’t find them)
Combine this with a plan to leave the cats alone for more than 12 hours…mine would be going absolutely bat shit after one night alone, but I did house sit for a cat when I was in high school who was quite content to have me only come by every other day or so. But a full week and a toilet trained cat? That sounds like a recipe for disaster and maybe even death.
Not every cat will take to it, but you get something like this: https://litterkwitter.com/
It was great in my old apartment, but sadly I can’t do it in my current one as you need to go through the bedroom to get to the bathroom and he’s not allowed in there!
I flush all my cat litter down the toilet anyway, it’s specifically made for that (I use green tea scented tofu litter)
To be fair, there is literally nothing good about keeping cats in regards to wildlife, environment etc. Just pure and simple selfish pleasure 
(I like cats, dont shoot the messenger)
But I agree, not dumping into the water table and/or the ocean is pretty spot on. Composting is probably the best route if dealing with waste. Garbage truck isnt great either. either soil, water or air pollution from that method.