Some public lavatory cubicles have an externally viewable indicator.

Usually these only have two states, perhaps shown as green and red, or "vacant" and "occupied" or similar, and these are tied to the door-bolt's position through a mechanical linkage.

Why not make this more unnecessarily complicated?

The modified indicator has a full wheel of alternating options "vacant", "occupied", "empty", "full", "open for business", "business in progress", "idle", "busy", "next please", "please wait" and so on.
The display wheel is rotated in lockstep with the bolt location with the use of a ratchet mechanism.
-- Loris, Aug 13 2021

I read this as having an indicator for "so on".
-- 4and20, Aug 14 2021


+ I would also like one to show “out of toilet paper”

If people aren’t nice enough to rotate the dial for this, there could be a mechanism attached to the roll dispenser that clicks over when the roll is empty.
-- xandram, Aug 14 2021


Don't forget an indicator as to how good cell reception is, within.
-- FlyingToaster, Aug 14 2021


Need one for 'yes, it's technically available, but are you sure you want to come in here?'
-- RayfordSteele, Aug 14 2021


What [xandram] said.
-- pertinax, Aug 14 2021


[RayfordSteele]; yeah, definitely needs a "biohazard symbol" option.
-- neutrinos_shadow, Aug 16 2021


"closed until [adjustable clock]" because sometimes you know you'll be in there for a while
-- mace, Aug 17 2021


Approved. [+]
-- xenzag, Aug 17 2021


[+] Another good strike against the repetitive* boredom. Two, one-arm bandit display drums?
-- wjt, Aug 17 2021


Does 'idle' mean empty stall or stalled emptying?
-- nuclear hobo, Aug 19 2021


[Defecated]
[Defected]
-- 2 fries shy of a happy meal, Aug 19 2021


"I am just going inside, and may be gone for some time"
-- lurch, Aug 19 2021


//a mechanism attached to the roll dispenser that clicks over when the roll is empty.//

This is eminently possible and would potentially save a lot of... hardship. The way to do it would be to mount the toilet paper dispenser on the door. Then, have a clear section in the door so you can see the level of the toilet paper - It need only be a strip, and can be somewhat lensed to enhance privacy. The interior can also have a window, just in a different part of the roll, so you can't see through.

Thinking further, having the dispenser on the door is inconvenient, it's in front of you at a 90 degree angle, so, put the door on the side. This has a number of advantages.

It should hinge on the side away from the toilet, so it closes and locks close to the person on the toilet, this way, the lock can easily be seen & possibly held in an emergency. The toilet paper would be back in the conventional location. If anyone has tried to get an old/frail person onto a toilet, backing into a narrow stall is about the worst situation. What you want is side access, you can take off the arm of a wheelchair or whatnot, and just slide them over. Handles etc. all help.

//has a full wheel of alternating options//

"Give it half an hour", "Toilet paper needed!!! Help!!!", "Might be a while, I'm going through a lot here", "I'm one step away from a medical emergency", "Bowell cancer, I knew it", "Don't worry, I remembered now, it was beetroot", "seat only has one bolt, so, be careful not to get anything trapped", "Automatic flush mechanism has droid-rot", "good/offensive graffiti", "Mystery Stains", "I just need half an hour away from the kids, OK?", "This one still has a reassuring smell of bleach". The last one should be the default setting used by the cleaners, a better mechanism than a half-hearted initial on a 4 year old form on the back of the door.

Perhaps some for popular tourist areas: "I'm adjusting to new local microbiology/food/hygiene standards", "I'm having to translate the buttons", "This is a strange and new form of toilet to me", "Did someone steal all the toilets, or are they supposed to be like this?", "I'm uncomfortable with people having full conversations on their phones in here, though I am texting".
-- bs0u0155, Aug 20 2021


I don't think we need a manual communication system. Ot at least, I think we can unnecessarily complicate it by adding more technology. It feels to me like there is currently sensor technology enough (body position, sounds, scales for changes in weight) to allow for a progress bar style readout on the outside of the door, indicating how far along the process the occupant is and underneath the green progress bar, smalltext status updates e.g.
Just occupied;
Ready position;
Settling in;
Reticulating splines;
Volume shift in colonic zone;
Crowning;
Amidshits;
Splashdown;
Debriefing;
Wiping;
Pokemon Go;
No longer docked;
Trousers up, stand clear.
-- calum, Aug 20 2021


//scales for changes in weight//

Complex algorithms might be needed to discern weight changes from transient "thrust".
-- bs0u0155, Aug 20 2021



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