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Show HN: Elevators

john.fun

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Re: Show HN: Elevators

#191

Post by kadoban »

vova_hn2 wrote: post #177
acomjean wrote: post #117

Earlier quoted context omitted.

Is it because the criteria is wait time not travel time? Destination dispatch would avoid some extra stops on the trip. I just visited a new building with destination dispatch, so it seems to be still around. My EE roommate in college had to build an elevator circuit as a final problem. It was on a bread board and had a bunch of call buttons and had a motor and a clear disk with black squares so it could figure out w…

> Is it because the criteria is wait time not travel time? Yeah, it doesn't make any sense to optimize wait time instead of total time from pressing the button to reaching destination.

Human psychology might allow other reasonable criteria even if perfectly rational choice is just total time to destination.

Re: Show HN: Elevators

#192

Post by frizlab »

I’m surprised to not see any reference to the Happy Vertical People Transporters from The Hitch Hiker’s Guide to the Galaxy!

Them elevators are able to see into the future to be there even before we call them. Come on!

Re: Show HN: Elevators

#193

Post by tomduncalf »

tegling wrote: post #142

One case not covered, I believe I saw at London Heathrow was where 4 cars essentially moved people across only 2 floors. With only 1 centralized button, only 1-point-something car was effectively moving people on average, because people had to wait for the currently filled car to have its doors closed and starting to move, before hitting the button to call the next car to pick them up. Imaging 100-200 people in line…

Ha I know the exact ones you mean well, going to the train from terminal 5? I couldn’t have told you what was up with them but they seem very inefficient and there’s always a queue! Thanks for explaining

Re: Show HN: Elevators

#194

Post by ncr100 »

Next time please add a cool potted plant that appears whenever you open a door, for the final full sim at the end of the article. Decorative plants for the win.

I love this by the way.

Re: Show HN: Elevators

#195

Post by tuetuopay »

Meanwhile, the elevator at my apartment building: hey only one floor at a time can call me! And no queueing, you must wait for me to be idle for someone to call me. (And yes, often someone beats me and presses the butter faster than I can).

Re: Show HN: Elevators

#197

Post by vova_hn2 »

brandonpelfrey wrote: post #6

For folks that have never seen elevator scheduling the game: https://play.elevatorsaga.com/ Enjoy this rabbit hole :D

Very fun indeed!

Can't believe, that this [0] solution to Challenge #5 actually worked, lol

Challenge #6 is "Transport 40 people using 60 elevator moves or less". Unfortunately docs don't make it clear what exactly counts as a "move".

[0] https://gist.github.com/vovanz/66e4396934ac656a8f8c32fcee43d...

Re: Show HN: Elevators

#198

Post by joshjob42 »

brd529 wrote: post #60
dperfect wrote: post #56

Destination dispatch should be no worse than standard up/down buttons, right (at least in theory)? It provides additional information about the destination, but it should be possible for that information to be interpreted as if it were just an up/down button press, so RSR could still be used. I have a feeling a better algorithm could in fact make destination dispatch slightly better than RSR... or am I missing someth…

As the article says, the problem with destination dispatch is that it 'locks in' an elevator. The passenger gets told at call time what elevator to go to, and it can't change that mid flight. RSR has the advantage that the passenger has no idea which elevator will come, and so RSR can change the elevator they will get in real-time as conditions change. This was an insight I had not considered before reading the artic…

Seems like the obvious solution is to put a bank of floor numbers above each elevator and when one arrives the floors it has been assigned to go to light up and the people going to them get in that one. So each person only needs to quickly to see if it's going to their floor or not, much like they need to look to see if it's going up or down. Then you can dynamically dispatch elevators right up until 5s or so before it arrives at a floor, with full knowledge of not just up/down but also destination. (And hell make 'em say how many people are in their party too so you also know how many people are traveling and where.)

Re: Show HN: Elevators

#199

Post by danfunk »

AI use in the creation of this article is inconsequential. There is obvious joy and high fidelity information here. Perhaps some vibe coding made the animations easier to develop, and made it possible to produce this in reasonable time. Who cares. Love of craft is evident. What more proof do you need that this is worthy of human attention?
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