Hi, Habr. Today is the eve of a professional holiday of such important, necessary and useful people as programmers. And in honor of this event, we start a geek-drawing of prizes, which Mail.Ru Group and Habrahabr jointly conduct.

Everyone who has an account on Habré can even take part in the draw, even read-only. Make it easy: just log in, go to the draw page and click the button there. There are a lot of prizes for the winners of the draw, and all are valuable, so we recommend to take part. Details - under the cut.

The birth of an idea

Somehow, we started talking about the fact that technical progress is often driven not by a thirst for knowledge or some kind intention, but by laziness. Simply, a person wants to do something easier and simpler, and for the sake of it creates something new. For example, 23 years ago, programmers from Cambridge invented a webcam, so as not to go to the coffee maker. In gratitude for this invention, we wanted to create some interesting project in which webcams would be an integral part. "Programmers, they soon have a holiday, webcam." And so the idea of ​​our geek raffle was born.
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How things are arranged

Naturally, we wanted to make a joke that would be as close as possible to every self-respecting geek. And after discussing the different options, we implemented the following: a brave wisher, who wants to take part in the drawing, enters his page and presses the button. After that, its data is sent to a dedicated server and stored in the database of participants. On the remote printer, the ticket of the participant is printed out with his habra-nick and avatar. After that, the most interesting and geeky begins.

First, the process of falling into the box of a newly printed ticket is removed. Coming out of the printer, it gets into the inclined transparent tray and slides on it to special stops. Here, the appearance of the ticket is recorded by a sensor that initiates recording from one of the webcams. A link to a small video with a printed ticket is sent to its owner by email. After that, the stops are lifted by a servo drive, and the gear located under the tray causes the ticket to fall out of the tray.





We decided to measure the total weight of printed tickets. And for this, inspired by the idea of ​​the machine of Ruba Goldberg , they invented the following design. The ticket is not just printed, it automatically falls into the transparent box, which is suspended from the springs. Naturally, under the weight of tickets, he will gradually fall. But the weight of one ticket is insignificant, so we adjusted it for exact measurement:

a) a distance sensor located under the box and fixing its lowering when a ticket hits;
b) an illumination sensor located on the side of the box and measuring the shift of the gradient scale on its wall.

Both sensors are connected to the Arduino, and based on their readings, the current weight of printed tickets is calculated. It can be viewed at any time on the site of our project.

Transparency in relationships

The second webcam round-the-clock removes the entire structure, and anyone can at any time be convinced of the fair conduct of the rally. The whole structure is located in a specially allocated space in the Mail.Ru Group office. Ideally, no manipulation of our installation is expected for the duration of the drawing, with the exception of adding paper to the printer.

Also, the rules do not provide for participation in our geek raffle of Mail.Ru Group employees and their family members. To our colleagues was not insulting, we will hold for them a separate mini-rally.

Prizes, gifts, that's all

Our geek-rally prizes last long, right up to October 31. In Halloween, the official ceremony of determining the winners and awarding prizes. We have prepared 28 very valuable prizes - laptops, smartphones, tablets, gesture control interfaces, fitness trackers and other nice gadgets. In general, what is necessary.

Winners will be selected randomly by pulling tickets from boxing. The whole process will also be continuously broadcast online. The lucky ones will be able to pick up their prizes on their own, or we will send them by postal service.

We are also proud to announce that Anatoly Wasserman has become a special invited guest of our geek-rally . The honorary gentleman of the Medal “Internet backup copy carrier”, he worked as a programmer for 20 years, so tomorrow he will have the right to celebrate his professional holiday.



For competition questions, contact media_magnit