A little background. Grandma stands up then wipes instead of wiping before getting up. Thus, at times, a dollop of poop falls to the ground. She proceeds to step in it and smear it all over the house.
Possible remedy. I thought about laying down those thick rubber honeycomb mats they have in restaurants. Those are designed to allow matter to fall through and not be stepped on. Not as much anyways. It would mitigate the poop smearing. The problem is that it would be a trip hazard with a 1" or so lip.
The solution. I devised a way to catch said poops before they hit the ground. Took some experimentation but I think I have it. Last night, it caught it's second poop in a row. One more catch and I'm putting the steam cleaner away.
I thought about a bunch of ways to do it. First, Use a structured light camera to detect the poop dropping in 3 space and use a fast servo to power a scoop to intercept it. Maybe train an ASI to account for the non uniform density and thus possible weird trajectory of the target. In the end, F=MA killed that idea. The amount of acceleration needed would result in too much force. A miss contacting grandma would be bad.
So I moved into suspending a sheet of rubber under the commode. The problem is that her legs would deflect the sheet so much that it didn't catch anything.
Next, I evolved that idea to use something less elastic. I hung a absorbent pad under there instead of the sheet. Same problem though. The poop would just fall pass the deflection. Then it hit me to use a spring to deflect out the middle of it. I used a big zip tie wrapped around the frame for that. It pushes out the edge of the pad between her legs. Not very far but far enough that it catches her poop. Fringe benefit is that it also catches any stray pee that hits the bottom of the commode seat.
Just catching these 3 poops makes it all worth it. Otherwise I would have to spend hours after each incident cleaning everything from her feet to her shoes to the sheets to the carpet. You get the idea. Even after the cleaning, the carpet is never really clean is it? Yuck.