Machine in St. Petersburg - the operator in Moscow

Long entry h4>
 



In last topic we tested HD FPV with our beloved Virturilkoy as a video source. Then tests showed that everything is fine, first-person view in the management model is quite the real deal. The main thing - it would be a normal link. While HDMI input for Virturilki in the production process (by the way, already has first test sample , but the driver is not ready yet), decided to search More options for the link. In the comments it was a lot of humor to the topic 4G, so we thought - why not?



In general, Virturilka was installed on the machine (low-speed, but vseprolazny Chinese crawler), is connected instead of the standard RC-receiver. In Virturilku plugged the modem from an unnamed company (but everyone understands that it Yota). Onboard Virturilki has established four channel PWM, so that it is just "out of the box" can function as RC-side four-channel receiver. To control the machine typically needs only two channels, so that even brute obtained. On Virturilke server running team with a proud name rcboard, which I did the last few days. Softinkoy turned out pretty cool, but I will not publish until you going to clean some shoals (as without them).

On the management side - an application that takes the signal from any of windows joystick. Since most RC HW (hardware management console, in short) is the trainer port, you can connect this very Appa to a computer via USB-adapter. As a result, Appa is seen by the operating system as a conventional joystick. By the way, under Linux it's much easier in terms of programming, but under Windows had to learn the unknown C #. In short, on the control side application runs .Net, which is treated with the joystick, and sends packets to Virturilku.

Since in our case Virturilka comes to internet through Iota - the question arose as to send her team. Teams are on UDP (all advise - only UDP, no brake TCP), and at Iota not white ip. White ip you can connect to a legal entity (400 rubles per month). We have something we can connect, as there is a legal entity, but it is non-kosher. So that was implemented way to send commands to the board and without white aypishnika. The method, known as UDP Hole Punching. Specifically, a simplified version of the method. Since in this topic, I just want to show the test results, so to speak, for starters, let's implementation details slightly delayed, because I want to add a full DUP Hole panching to do any control method, and now requires white ip on the management side.

More would like to speak about the type of control. The same Parrot ArDrone controlled tablet / smartphone. Our Soup (which are based on Virturilki) many controlled tablet / smartphone. But this does not mean that this type of control is good. Honestly, this is the kind of lousy management. When managing than ever to feel the controls to only look at the picture from the camera and not think "and I got a finger on a virtual joystick." So what better than normal rtsshnyh ann do not yet invented. Is the USB drive / pedals, they also supported my softinkoy (of course, this is just an ordinary joystick w). For cars it is a wheel and pedals - the nishtyag.

How is it done h4>
 And now the case. Yesterday morning I finished writing this same command to the server (which runs Virturilke) tried surprised what works. Told his colleagues and was about to go to sleep. However, a colleague was on communication and volunteered to speak first tester. So leave could not sleep, had to get dressed and move with the machine on the street. I watched the machine and ran her colleague from St. Petersburg. Signal Iota I've got not much, so that colleagues report (on a mobile phone through Skype) that the video goes, but often falls apart. Telemetry from the board (via telemetry taxiing given to the battery voltage and signal parameters Iota) showed that the signal is really lousy. But the machine was traveling, video somehow gone.

By the way, about the video. After the test HD video in 1280x720 resolution has no desire not to return to the normal 640x480, so that all testing is done it in HD. For Iota bitrate lowered to one megabit, but even with one megabit 720p looks better than 640x480.

Encouraged by the result, a colleague ran to a nearby shop and bought hobbiyny there exactly the same crawler. Connect it to the test with Virturilku firmware - it five minutes. So after half an hour already realizator went out into the street, and I hooked up to a computer Appa and tried to steer.

It turned out that Peter, in any case, one sleeping area (in this video are not included) and in the center of Iota works much better than I do about the house in Moscow. So I drove without problems on a typewriter sitting in a chair in the six hundred kilometers from it:-) Delay generally not felt, the video does not disintegrate, just everything is perfect.

So it went with the implementor Crawlers Palace Square. If we are testing - so in an interesting place:-) Enlarge video bitrate somehow did not think, although there is clearly a considerable margin. So all pokatushki passed it with a stream of 1 mb / s. At first I was afraid to go fast, but soon became very accustomed and really miss rate crawler. Really, in this excellent video and can be much faster to drive. But other machines on hand until the present, so let anything.

In general, this is what happened as a result. The tests were random, so that shot than necessary. Even record stream, which normally works under linux, under Windows, as it turns out, does not plow, you have to do differently. So that the screen had to record the normal of webcam, plus the view from my goproha recorded.

Well, the video itself h4>
 

As I wrote above, the server commands and application of windows rulilku publish on days when Fixed minor bugs. Visit our forum , everything will be there. But the description of the server commands, possibly on a separate topic Habré pull.

P.S. To be honest, I did not expect that everything will turn out so good. Iota was better than I had thought about it, anyway, in Peter:-) I do what I'm accustomed to taxiing different things, but go to the Palace Square and the Nevsky, sitting at home in Moscow - it was very cool. And most importantly - all on the basis of our offspring - Virturilki:-)

Source: habrahabr.ru/company/virt2real/blog/223145/