

Elevator algorithms - vedant
http://vedantmisra.com/2011/12/elevator-algorithms/

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zumwegwerfen
My office tower has 6 elevators. 3 transfer buses are coming in from the
subway @ 8:50, around 120 people are coming trough the security gates and
approaching the elevators more or less simultaneously. It takes me approx 20
minutes until i get to my floor every single morning, because only one
elevator comes at a time and since i am a gentlemen, i usually let the ladies
go first. Even more, you can call an elevator only when another went off,
otherwise the full one won't move and will open it's doors instead. OTIS, i
hate you.

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thangalin
Do elevator algorithms communicate with external systems, such as swipe cards?

For example, when an employee swipes through the security gates, the elevator
is called.

Also curious if elevators use statistical analysis for predicting trends over
time. A four-elevator system in an office tower would likely give the cars
preference to being near the first floor at 8:30am. Is this what fuzzy logic
schedulers do?

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Maven911
> For example, when an employee swipes through the security gates, the
> elevator is called

Not that I work in the industry, but I highly doubt it. Only be cause when I
look at other fields such as communications, it is only in the past few years
that the idea of unified communications has taken hold, where separated
systems can talk to each other, think e-mail connected to voice-mail, etc. So
if I had to guess, I would highly doubt it

This could be an interesting area to patent and work on.

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callumjones
There would have to be some sort of standard API where multiple companies
sharing a business could talk to a central lift system to share information
about their employees.

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roryokane
Another optimization criteria not mentioned is energy efficiency. I would
guess that elevator manufacturers try to prevent elevators from consuming
excess power. It would probably be bad if an elevator went back and forth
between the same floors many times with no one inside it, just because it
expected a slightly higher chance of finding a passenger at the destination.

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Maven911
I have always felt that other industries do not require the same amount of
learning to keep up with and that in general since the knowledge base is
lower, you can become and remain an expert with less amount of knowledge then
software engineering/telecom/computer engineering.

The reason I feel this way is because there is not as many people involved in
other fields, the information is not easy to access (think RFCs, programming
language guides/books/frameworks etc.), and there are not that many people
blogging & writing on websites about the complicated details of their
respective industry.

It was still interesting to see that a book on elevator function theory was
mentioned near the end of the article, but I doubt that this or many other
fields require a lot of complicated know-how (and that needs to be constantly
updated). Could I be wrong with my assumptions ?

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john_b
Your point is barely (if at all) relevant here. To the extent that you are
specific, you are wrong too.

If you want to pass blanket judgment on the complexity of an industry and the
technical capabilities of its engineers, you should at least pick a better
metric than the amount of blogs and guides that discuss the technical details
of that (still unspecified in your post) industry. The world of programming is
unique in that a common culture of openness and freedom of information
pervades it. Other industries do not have a culture even remotely similar to
that. If an elevator control system designer blogged about how his wonderful
algorithm works he might be fired (since the algorithm is the property of his
company). Unlike the world of software development, where the product is code,
in industries that require heavy, expensive hardware (like elevators, for
example), a lone software developer is useless. You need people to do CAD and
perform load analyses on all the critical components, installation
technicians, lawyers to handle safety compliance, etc. In other words, you
need a big (or medium, at least) corporation with all of its hierarchy and
need to control information. And when you work in that kind of environment,
you don't just blog your thoughts whenever you feel like it or discuss
technical details of your projects. Because they're not your projects; they
belong to the company and your code is just a fraction of the whole system.

I'm not just making this up either. I'm an engineer (who does a lot of
programming) in the aviation industry. Even if my company wanted me to blog
about what I do, I wouldn't do it simply because nobody reading the blog would
be able to understand it. The programming would be the easy part to
understand, but if you don't know the context of the work it won't make any
sense.

Your post makes a lot of assumptions, but it's good that you recognized that
you might have overreached when you made them.

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efj034f0
Cache link <http://vedantmisra.com.nyud.net/2011/12/elevator-algorithms/>

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jayanderson
I've wondered before why they don't have the list of floors when you call the
elevator instead of selecting it from within.

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jisaacstone
I've seen this in a few buildings before. There is a keypad - you type the
floor number and it tells you which elevator to wait at (for example 'g').
Worked really smoothly.

