News

Instead of building our own hardware we decided to focus on SokilLink software solution. Starting from now it is possible to use the solution on different Raspberry Pi boards (starting from Pi 2/Zero 2). Raspberry PI Camera (v2) is also supported.

Another news is LTE support : instead of relying on wireless data links we decided to implement cloud connections for SokilLink, making it possible to fly without any range limitations everywhere with stable LTE coverage. Since the connection is established over the Internet, there's no need for a ground station with a data link so you can control the drone from any location! Instead of using VPN services we use direct connection established between a drone and remote control which gives the smallest possible latency (which is about 150ms with Raspberry PI Camera).
To provide full support for LTE connections we have developed SokilLink Cloud service: currently it is only used for binding customer's drones to ground stations but there's more to come: flights logging support, simultaneous work with drones and much more! The service is already available at cloud.sokil.aero.

Instead of building a ground station, an Android device with a gamepad and SokilGCS application installed is all you need. You might check Logitech G Cloud if you want even more compact solution: it's a great gaming console with built-in gamepad.

And the last but not the least: SokilLink Cloud is completely free for personal use: feel free to try it by following the manual.

Description

In modern video streaming systems used in UAV and other applications which often require low latency, it is important to have a reliable way to measure the latency. Usually people use so-called 'stopwatch method' which envolves running one on some screen (e.g. on laptop or phone) with camera pointed on it, then taking a photo of both screens so you can compare both values and calculate the delay.

However such way has some disadvantages:

• You have to manually calculate each value
• It's sometimes hard to take a photo with clear time readings because of long exposure time which is usually applied in low light conditions, so you get values blurry
• It shows latency at exact monent of time, while it can differ because of camera frame rate
• You have to take a lot of photos in order to find min/max/avg latency

While working on SokilLink we realized that we need some faster and handier way to measure the latency, thus we decided to automate measurements. There were different setups but some of them used specific hardware, others didn't explain how to build them, so let's reinvent the wheel:

After a long time of development we are happy to inform you that SokilLink WIFI5HP is available for order!

The solution allows to transfer high-definition video with low latency over an encrypted 5GHz Wi-Fi link, draw telemetry overlay on top of it, control a UAV using a gamepad in real-time and establish telemetry link between a vehicle and your favorite GCS.

The product consists of on-board and ground modules. On-board one is only 35x70mm big, what allows to use it even on 450 class multi-copters. It also includes FullHD camera with 100-160ms end-to-end latency. The module can be connected to an Mavlink-capable autopilot in order to read UAV telemetry and control it from GCS or gamepad.

Ground PC has HDMI out for video displaying with telemetry on top of it, USB input which allows to connect gamepad, it also works as WiFi Access Point mode so you can connect your laptop for configuration or control.

Thanks to modular design, the solution may be extended with third-party cameras and digital data links support.

Usually it's hard to test complex system on a flying vehicle since it may crash or get lost because of some (even minor) bug. Hopefully we haven't crashed anything this year but we decided to test our system on a RC car until we ensure that there are no issues. Another advantage is that we have plenty of space on it so we do not worry about hardware dimensions and weight during tests.

We have faced many issues since last post.

Main news is that we eventually have advanced to radio link tests. On the attached video which was captured from ground display you could notite multiple frame drops (and even rare ones right near receiver) which were for sure caused by unstable WiFi connection. Hope we will find a reason for such a poor performance soon (like not attached antennas or so).

Since last announce many parts of our software have been improved: we have better video stream recovery, it is possible to see radio link statistics and configure various components with a bundled configurator application.

During all this time we've received a lot of emails from interested companies and individuals. We're really happy that there is such a big interest for the solution. Although it was told many times that the product is going to be available in 1-2 months now we realize that it was way too optimistic. At this time we wouldn't give you any expectations but saying only "It's done when it's done" :)

So now we are proceeding to radio links testing (mainly WiFi ones at the beginning) and since all other system components are pretty stable we expect things to go much faster. There should be more news followed by flight test footages.

We are very happy to tell that SokilLink is very close to release. During last few months there were many improvements implemented thus making the entire solution much more flexible and reliable. We have also taken into account your wishes and now want to tell you more about the...

Hardware

You may remember that entire idea of our development was to make something similar to 3DR Solo on-board PC but much more lexible. In Solo there were two computers: one in the drone itself and another one in RC. So we're going to ship the same boards set.

Ground PC is an Intel-powered board performed in PicoITX form-factor. It has 2 USB inputs which allow to connect USB gamepads/joysticks or an USB trainer dongle which allows to use our system with conventional RC like Turnigy 9XR. There is also a HDMI output which allows you to see HD video stream from your drone and telemetry overlay. Air PC is an i.MX6 board and is only 35*70mm. There are also an USB port, HDMI input for digital video and two DroneCode-compatible telemetry ports. Both boards have mPCIe port which allows to use high-power WiFi radios.

Mainly our system uses WiFi as data link, however we realize that it has some limitations. For those who need more long-range solution we're happy to announce to tell that we're also working on integration with one 3rd-party data link which allows to stream HD video up to 25 km.

It is hard to build a drone similar to devices represented on market these days.One may succeed in making UAV with great flight characteristics or payload, however it is much harder to integrate all drone device into one working system. There is always demand in video and control links. Knowing more info about drone systems is also good, so telemetry link is also often a requirement.

For Pixhawk-powered drones often the only solution is to use 3 different radio links for each kind of control. Situation with video is the worst: in many cases only old good (well, not so good) analog video transmitter can be used. But that's not last problem: all these transmitters should be placed on the drone frame and protected from influence of each other.

So we've decided to build a solution to solve all these problems. It had to give all features provided by each separate system (RC, telemetry and video transmitter) and much more. We also wanted one radio link to be used for all kinds of data.
So main features had to be:

• Using Mavlink protocol for all types of controls
• Digital video transmission from drone and displaying on RC screen
• Cameras control using their API
• Using USB HID devices for manual UAV control
• Flexible structure for easy integration...

And now we're happy to present SokilLink. It is a complex software solution for building a powerful drone. We are sure that it would give you all required functionality to compete on the market. Just contact us and we'd be happy to answer your questions and help you to make your product better!