How about algorithms to punish inefficient human behavior on elevators:
a. If people are on the elevator, it stops on a floor for a button that has been pressed, and no one gets off (as measured by weight), this means that someone must have pressed a button by accident. Switch from soft muzac to loud Rich Ashley music until the next stop.
b. If someone enters an elevator (as measured by weight) and within 3 seconds 2 buttons are pressed within 1 second of each other by the same finger (as determined by biometrics), that means some dumbass couldn't even press the correct button. Shock them on the second button press.
c. If the elevator is planning to discharge passengers (see a.), and people get on before people get off (as measured by weight), dump hot liquid on the rude entering passengers (those closest to the door).
d. Photograph anyone who summons the elevator by pressing the up or down button on their floor. If the elevator stops and no one gets on (as measured by weight), post their picture on elevatordouchebags.com.
e. If anyone farts on an elevator (as determined by sensors), identify them with a spotlight so that the sufferers don't have to guess who made them suffer.
f. If anyone gets on the elevator without a cart or baby carriage (as determined by sensors) and presses 1 floor down, go up 1 floor instead. When the door opens, flash a message, "Use the stairs next time!"
g. If too many people get on (as measured by weight), open door slightly and shake violently, knocking people out until the weight is under the limit.
Any other ideas?
(a), (c) I press all buttons as I exit elevator.
(b) gummi bear attack or similar.
(d) Arrive carrying large cumbersome object "Heh, can you call the elevator for me?" (then run away)
(f) is easily reversible: should send people as far away as possible from their intended destination instead.
(g) throw dumbells into passing elevators.
If anyone presses the button more then once they'll get the same lights as the traffic. So green for the cars, green for them.
Software engineering could (and should) learn a few things from mechanical engineering. People have been saying that for decades, but it bears repeating...
Instead of Jandy's suggestion:
>Am I crazy thinking it'd be a good idea to have an elevator which analyses its own usage patterns and adjusts its behaviour accordingly?
why not make the people adjust to the elevator's ideal behaviour?
EDIT: quote formatting
That aside, I think Jandy was referring to a different scenario than what you're envisioning. If you have a skyscraper, and a trendy new bar opens on the 36th floor when the 36th floor use to be occupied by an office, but the elevator was programmed to rest at the 36th floor only at 9AM, lunch hours, and 5PM, telling the bar they have to make their clientele come and leave at those hours for "efficiency" will not go over well. Instead, having an elevator that notices no one's calling from the 36th floor before 8PM anymore doesn't sound like a bad idea.
Although I agree, I was responding to the possibility of an elevator punishing behavior it didn't "like". Both what edw519 and I suggested would lead to "a whole office [...] following arbitrary elevator efficiency rules." It was intended to be a very tongue-in-cheek comment. I completely agree with both you and Jandy: a good elevator design would adjust itself to normal usage patterns and maximize efficiency within those constraints.
FYI it's Rick Astley, not Rich Ashley.
The game allows you to setup different patterns for different times of the day. It allows you to set wait floors, set which floors it will stop at, and even set patterns like skip to the top and drop off on way down. This last trick avoids the problem of needing to stop on the same floor on both your way up and way down, which would occur with normal elevators if say the elevator was taking two people up, one to floor 17, one to floor 20, and someone wanted to get on at 17 to go down.
In all the game was really fun (although construction was repetitive), and does make you think about elevator optimization for the rest of your life, I played it as a kid, and I am always thinking about how badly elevators are optimized!
What I did was sort of a hack, but worked, in the basement levels express elevators and escalators can go to any floor, so I made tons of them, and made tons of shops, all shops (they had highest population density). Virtually all of my tower was underground.
If you need lengthy instructions to show someone how to use your UI, you should reconsider your UI.
You are right that there's an initial curve, though, and I don't know how to deal with that other than just through the painful experience you described.
If this was a deadly choice, between an elevator and a trash compactor, it might make sense to over-sign it. As is, it's a trivial and obvious mistake, especially if each bank has a sign saying 'Floors 1-x are reached via the other elevator bank' for someone to read on their round-trip.
Part of the reason users are so clueless is because we go too far in padding their environment. People don't slice off fingers because the sharp end of the knife wasn't properly labelled - they exercise caution.
Then they retrofitted a similar system back at my corp HQ. It had you enter your floor on a screen on the wall right in the middle of the elevator lobby and it was (and is) kind of a pain in the ass...because when there's a crush of people waiting for the elevators, you can't get to the screen to enter your floor. When it was just the "up" and "down" buttons in the same location, the odds were pretty good that someone in the crush had already pushed the button you need, but...
I don't think owners of office buildings realize how painful it is to have slow elevators. We moved our office out of a 30 story building with 4 elevators, because the unbearable wait to get in and out of the building during peak times.
The interesting thing about "elevator" algorithms is that they're really very similar to the algorithms used to schedule reads and writes on a hard drive. Reading in some data is similar to picking up a person, and writing data can be thought of as dropping the person off somewhere. Regular (i.e., not solid state) hard drives have large cylinders of addresses. This is sort of like a rolled up building.
I don't have the output in front of me, but I think that both LOOK  and SCAN  algorithms performed very well. It's cool to note that the SCAN algorithm is referred to as the "Elevator algorithm" by Wikipedia. Clearly we're not the first to go down this rabbit hole.
(E = the number of elevators, N probably should be the number of floors, no idea what would make a good N)
I'm sure that if you snap shotted the LRU cache every few minutes you could build a pretty good predictive index for the patterns through out the week and time of day.
What might be interesting would be wifi/cell signal detectors that could pick up a cell when it enters the hallway and start moving the elevator already.
For example, you're on the 10th floor and want to go to the first floor. You press the down button. The elevator arrives, with it's "going down" arrow lit. You get on, and as you fumble with your fob, someone on the 18th floor presses the down button. The elevator now has a call on the 18th floor, and no destinations yet, because you haven't pressed the "1" button. Now you have a choice: press "1" and ride the elevator up to 18, knowing that it'll (eventually) go down to 1, or get off the elevator press "down" in the hope that another elevator will arrive before this one gets back. Of course, it's very likely that you don't notice the "going up" arrow, because you're fumbling with your fob.
I'm finding this happens surprisingly often, and I think it's a bug.
But in a system such as you describe you get on the elevator, wave the fob at the sensor, and press all the buttons. It'll only take you to the specific floor your stolen key will work on - narrowing the search time down to mere minutes.
Then they'd all end up sulking in the basement...
(of course, the most simple algorithm doesn't even use a queue! It just moves the elevator up until it hits the top, and down until it hits the bottom, opening the doors wherever there's a call request)
A smart elevator algorithm would adapt to the arrival behavior of people in a building through some clever stochastic simulation and modeling. For example, a simple model that could work quite well is to optimize for (read: minimize) the average time any passenger would wait for an elevator to arrive. But to do this, we need to model how frequently people request an elevator on each floor over the course of the day.
Modeling elevator requests
- We can assume that the number of people who request the elevator on each floor is a Poisson process with a mean of n. On a representative day (i.e. for an office building, choose a weekday), we can observe the number of people who arrive at the elevator each hour. This data would drop in as the n in our Poisson arrival processes.
Computing optimal solutions
- Using a statistical library, we can start generating simulated arrival data and apply integer optimization algorithms to determine which floor the elevator should rest on when there are no elevator requests, for each hour of the day.
Its definitely much more complex than that (e.g. the ground floor elevator could take people down from floors 2 & 3 or something, depends on time of day, etc.), but if the author's intention was to station one elevator at ground level and another in the middle, floor 7 is the better choice.
In that building, you go to the security desk and tell them where you're going. They call the elevator for you. You get on the elevator. It has no buttons inside. The desk sends you up to the permit office.
When you leave the permit office, you press a button next to the elevator and it shows up and takes you to the lobby. There are no other options for you.
Studios got paranoid about security post 9/11. Which I guess makes some sense.
But why the film permit office is inside one of them, I'll never know.
Have your bank of elevators start with a simple "best guess" algorithm, and then learn how to improve that algorithm. If the last employee of the building is ready to leave at 11pm, there's no reason the elevator shouldn't be at that floor waiting after a learning period.
I walked by dozens and dozens of emergency vehicles this morning because of this horrible thing: http://cityroom.blogs.nytimes.com/2011/12/14/three-hurt-in-m...
My last office was in an older building like that and had a set of elevators that were chronically behaving erratically, so that kind of freaked me out more than it would otherwise.
I would say that around 5pm you have more people going down than up so this algorithm falls flat on it's face.
I don't think you could write 1 algorithm and it works for everyone. You could generalise it to apartment buildings but I think there would be a pattern of more people going down at the beginning of the day than at the end of the day too.
The algorithm needs to take into consideration the type of lift (lifts in an housing complex vs commercial building) and time of the day. During morning hours, the lifts in an housing complex might more frequently travel towards the ground floor while the one in a business complex would be travelling up.
Also, there could be buildings where the top floors might have more tenants than bottom ones or the reverse.
There is a scope for self learning algorithm that can adjust its idle position depending on past behaviours.
But elevator algo becomes more complicated when two persons press the switch at same time for the lift. One is at 2nd floor and wants to go up, the other at 4th and wants to go down and lift is at 3rd floor :-)
Using my workplace as the anecdote the elevators get massive usage at 8:00AM as people arrive at work, the majority of calls are from 1st & 2nd floors (you can enter the building on both floors at 8:00, noon and 5:00). After that there is the 9:30-10:30 coffee rush with elevators going up and down. The noon rush, afternoon coffee and evening rush.
Those are the peak points of the day with simple scenarios for when people are most commonly going up down so it wouldn't be difficult to implement scenarios where the algorithm changes at a time.
The tenants of a large well-to-do apartment block kept complaining that the elevators were always too slow, and they hated waiting in the lobby for the next available elevator. The apartment manager spent some time investigating the cost of installing faster elevator motors before he came up with a much cheaper solution: He installed large mirrors in the elevator lobby; the complaints stopped.
I suspect the author has observed more residential towers than corporate towers? Otherwise I would imagine he would find that these practices are usually followed. Except for the door remaining open one, I never see that... maybe a fire code thing?
When the elevator is full, it should not stop for people who have pressed buttons not inside the elevator.
We don't walk enough, that's a known fact.
Elevators are bad for your health. Take a walk.
However Delevators are good because most accidents happen when you go downward.
Hence, Elevators going up should be for really older people only (unless you're in a hurry or carrying something heavy or already in good shape...).
Fight for Delevators!
I'm reminded of the 'Moving Platform' idea proposed for high-speed trains fairly recently though, and I wonder if there's anything there that could be reused.
What would a packet-switched elevator shaft look like? (Lots of small cars, which divert to individual 'station' queues for each floor, and latch onto a continuous moving belt at fixed intervals - shades of ATM)
Also, what about escalators? What standard arrival distributions do designers work with?
What the hell kind of behavior is that?