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Show HN: Elevators

john.fun

231–240 of 426 posts

Re: Show HN: Elevators

#232

> Destination Dispatch [...] are in general worse I wonder if this is an artifact of how the author used random destinations. I worked in a building that used Destination Dispatch, and the common travel pattern seemed to be: - Everyone who is not on the ground floor generally want to go to the ground floor. - People who are on the ground floor generally travel in large groups to the same destination. This happens bec…

This is case where you need to make sure your test data reflects real-world usage or you end up optimizing for the wrong thing.

Ideally a new elevator installation would have a trial period where they record usage and then run it through a simulator like this to determine the optimal strategy for that particular building. And you'd want to re-run it every once in a while as the building tenants/usage changes. I wonder if this actually happens, though.

Re: Show HN: Elevators

#233
post #221
post #17

The biggest problem I always have with elevators is not the algorithm, it's the people seemingly being unable to grasp the concept of pressing either the up or the down request button, depending on where they want to go. Almost always I find someone will press both, because "then the elevator comes faster". Completely ignoring the fact that they end up going the wrong way first half the time, and adding an unnecessar…

I often enter it in the wrong direction. Like let's say elevator is at 5, I am at 1 wanting to go to 3, and before I arrive there is already someone else at 1 wanting to go to -1. I'll get in with them going DOWN so that it doesn't have to stop a 2nd time on the way up. There are also other situations where I'll press it in the wrong direction if I think it's already likely to stop on the way down (due to me being on…

That’s great, but a lot of buildings don’t tell you where the elevator currently is when you are about to press the button.

Re: Show HN: Elevators

#234

> Destination Dispatch [...] are in general worse I wonder if this is an artifact of how the author used random destinations. I worked in a building that used Destination Dispatch, and the common travel pattern seemed to be: - Everyone who is not on the ground floor generally want to go to the ground floor. - People who are on the ground floor generally travel in large groups to the same destination. This happens bec…

Yeah, and definitely is not the right story for hotels. His premise of "morning traffic mostly from lobby to floors" is completely false in an hotel where you get it both ways due to people going down for breakfast and going back up and the down once again. I see hotels with the kiosk model changing the UI depending on breakfast rush hour

Most interesting hotel elevator system I’ve seen was in Washington DC.

Instead of hitting the call button, you started the request with your floor. Then the system would assign you an elevator (there were 6 cars as I recall).

I assume this gave the system more accurate routing data to make it more efficient for everyone.

Re: Show HN: Elevators

#235
post #57

Earlier quoted context omitted.

I don't think I've ever seen someone do that

Because most buildings now they just put one button so people stop clicking both

Nondirectional calls are mostly found in very early (pre-war) or small building (3-4 floors) installations.

Re: Show HN: Elevators

#236

Very cool. I would be curious how elevator banking (elevators split into different floor ranges) and double decker elevators impact this.

I thought double decker elevators were a failed experiment. I don’t think anyone is even producing them any more.

Re: Show HN: Elevators

#237

Earlier quoted context omitted.

For these people, replace the buttons entirely with a voice-activated destination request on proximity.

Full circle back to elevator operators!

More like Star Trek turbolifts. Make them grab the handle first for that TOS feel.

Re: Show HN: Elevators

#238

All I want to know is why the heck I can't un-press a button I pressed by accident. This should be very simple. Press once to turn the button on, press again to turn it off. Or I guess you could do long-press to turn off or something if you're worried about confusing people, but I really don't think that should be necessary. We know how toggles work. The button lights up when it's on.

In some old systems with buttons that actually pushed in and popped out upon arrival, you can pull them out to cancel your call: https://news.ycombinator.com/item?id=37385826

More examples:

https://www.youtube.com/watch?v=JzC5Bpz-PkQ

https://www.youtube.com/watch?v=xYtsNxzDR50

Re: Show HN: Elevators

#239

We used to do this as an interview question at my current job. We didn't expect people to solve it necessarily, and we just specified to solve for a single elevator car. We just wanted to see how people would break down the problem. Even at that relatively reduced level of complexity, it's quite tricky to figure out how to prioritize who gets served when.

I’ve gotten that interview problem! From a French company no less.

Re: Show HN: Elevators

#240
post #130

Aside for the algorithms and how well they work, there is a psychological aspect to how people perceive "wait" times. It turns out just waiting is very annoying. But having people do anything during that same wait period → perceived as progress → not upset. An example iirc was waiting for luggage at the airport. It takes min of x minutes for the first bags to show. In one version, passengers went directly from the ga…

I don't see how that's perception then? It was just made inefficient on purpose.

If I have to walk to the luggage area 10min and wait another 10min for my luggage it's not the same as if i walk 5min to the luggage area and wait 15min for my bag.

Yes, total time is the same but one scenario is acceptable because it feels inevitable and is under control (cannot personally move across space/time faster) the other is not because it feels like it could be improved (staff could unload bags faster).

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