I'm a UAV newbie and I am investigating the myriads of possibilities in building a UAV platform. I have chosen the ArduPilot mega + IMU as my autopilot platfrom and all is good with that. The next thing is to figure out the groundstation setup. There seems to be many ways of doing this, and all solutions are not compatible with each other :) Now to the question:
- I will use a 1500mW 1.3Ghz video TX on the UAV for the video feed.
- I will use a OSD to display "telemetry" data on the video feed. (Remzibi OSD, ezOSD, Ikarus OSD)
Now, which OSD would be best for the ArduPilot setup? Remzibi OSD can be integrated with the ArduPilot IMU data, so that is good. The Ikarus OSD have implemented telemetry data over the videofeed, which seems to be a good way to use an existing radionlink for getting data from the UAV to the groundstation. ezOSD uses the right audio channel for transmitting telemetry data, also good but I don't know what is better in this sense(audio vs. video embedded telemetry?)
Now, is there any way of getting the telemetry data from the ezOSD or the Ikarus OSD integrated with the ArduPilot data(so that I dont need multiple GPSes and IMUs) and also to get the telemetry down to the ground station? QGroundControl seems to be a good solution, specially when it supports Linux and OSX which I prefer to use over Windows solutions. QGroundControl supports ardupilot but telemetry seems to need Xbee or other radio modem as datalink. Is there any way of getting the telemetry to Qgroundcontrol over the video link(audio/video channel) from the Ardupilot?
Any ideas, pointers, suggestions on what is the best way to proceed appreciated. Maybe this can to be implemented in existing solutions and code developed to get it working?
Do I just need to split the the signals with a Y-cable or similar or do I need something else to split the signal?
I guess this is the standard way to go, however, it would be nice to use the Video TX for downlink to the groundstation so that no additional radiolink is needed for the telemetry. Anyone working on that for the Ardupilot?
I guess I will get a few Xbee units and try it out and continue to investigate how the data could be transmitted over the video/audio link...
Typically, you would just split the ground and the TX from the GPS to both your auto-pilot and your OSD. Then hook your X-Bee to your auto-pilot. There are two products that do what you're asking. Melih from Flytron came up with a way of encoding the telemetry data on the video feed and then decoding it on the ground, but I don't think the project ever made any farther than his testing stages. The other is a project from flipflop on RCG where he's using the Remzibi OSD with a special character set to screen scrape the data off the video feed. He also is developing his own GCS to include this.
It will cost you between $100 and $150 for the X-Bee hardware.
Hi HK & Kim,
The idea of transmitting all the telemetry over the video link seems like the way to go as it would reduce cost, weight and power - every little bit helps. Have either of you found any further information about it or tried it yourself yet?
Kim, you said you're using a 1.5W, 1.3GHz Tx. Have you tried it and found out what kind of range you get yet? I'm thinking of using 900MHz since it penetrates trees and such better, and using a high-gain antenna, maybe 2 for diversity, on a tracker, plus an omni.
I'm currently researching OSDs to use with the APM so I'd love to hear anything you learn and hopefully I can help you too as I try things out or if I come across anything interesting.