Skip to content

Picture of my ground station and sample video of a weak link

May 5, 2015

In this post I’ll explain my ground station that receives and displays video data using wifibroadcast

My ground station

Let’s start with a picture:

DSCF1118

Here you see my ground station. To the left you see my FPV glasses which contain a 7″ HDMI display and a fresnel lens. The enclosure is made out of foam and at the back a strap from ski-goggles is attached. Right next to the “helmet” you see a 3-cell battery that powers the system. On the right you find the Raspberry Pi A+ that has been integrated into a USB hub enclosure (there was enough room to keep the hub :). The Raspberry is powered by a cheap 5V DC/DC converter.

Sample video of a weak link

Following is a video where I have intentionally removed the antenna from the receiving wifi dongle. This shows some of the artifacts you could experience under bad signal conditions. I know, it looks really bad but remember: A lot of bad images and some good images is better than no images at all. And to get bad images like that with an antenna attached you really need a high distance or a solid block of the line of sight.

Advertisements

From → Uncategorized

7 Comments
  1. malkauns permalink

    Hi. How are you powering the raspberry Pi on your quad? I just blew mine using a 4S Lipo even though I used a 5V UBEC :(. The UBEC i was using is here:

    http://www.getfpv.com/lumenier-ubec-5v-5-5v-6v-5a-2-6s-input.html

  2. malkauns permalink

    I tested this with a multi-meter and it seems that the BEC is putting out the same as it gets in regardless of how the jumpers are set. No idea why!!

  3. cbl permalink

    I have a question about your goggles, I’m planning to build one too and found the display from pollin. But I calculated that in case of a 2x lense the focal distance would result in a very long
    lever hurting my neck. And in case of a lense with shorter focal distance it would result in a very large virtual screen in front of my nose. What lenses are you using and what is your viewing experience?

  4. Vlad permalink

    Hi)
    How can i run test video/signal or other source acros ./tx?

    sudo gst-launch-1.0 videotestsrc pattern=smpte | sudo ./tx -b 8 -r 4 -f 1024 wlan0

    it does’t work(

    • If I understand your command correctly then this would send raw video data. The data rate of that is most likely to high for wifibroadcast. You would need to add a H264 compression element into the gstreamer pipeline.
      Another way would be to send previously recorded video data as a test pattern. There you could control the data rate using the “pv” tool.

  5. assfucking comcom

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: