Developer

figuring out the Antenna Tracker

3691139590?profile=originalNot many people know but we have an piece of open source software for controlling an Antenna Tracker.  It's been built by Tridge (Arduplane lead developer) for use in the outback challenge.

Sadly we have no documentation and, as far as I know, nobody except Tridge has used it.  Still given Tridge's track record on building great software I suspect it works well and if it doesn't, I'm sure we can fix it.  So to not let this piece of code go to waste, I'd like some help from people who are interested to give it a try and help me figure out how it works.

Here's the little that I know:

  • It runs on any of our supported board (APM1, APM2, PX4, Pixhawk, Flymaple and perhaps VRBrain)
  • For APM1/APM2 users building the code is as easy as opening our hacked ArduinoIDE and selecting File > SketchBook > Tools > AntennaTracker and then building in the normal way.  For PX4/Pixhawk, our autobuilder doesn't automatically build a binary but I can provide one if people are interested.
  • It can control a Pan and Tilt gimbal like this or this found on servocity.com.
  • It may or may not require a GPS
  • It must somehow receive vehicle position updates from the ground station which has the telemetry radio that is connected to the vehicle. Maybe through a USB cable.  Tridge probably uses the python ground station, MAVProxy, to passthrough the vehicle position data to the AT but perhaps we can get MichaelO to build out a similar feature in Mission Planner.
  • I imagine this antenna tracker could also be used to keep a camera focused on the vehicle which might be good for easing the burden on creating videos of our vehicles.

So if you want to give it a try please do and stick any findings, questions or issues below. Alternatively Issues can go into the issues list.

I'll start sticking things into the wiki as they become clear.

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

  • MR60

    Also figuring out antenna tracker, I made this video clip to illustrate where I'm at (not so far obviously).

    The setup is a pixhawk used on the antenna tracker, in the middle between the quadcopter and a PC running mission planner (all links via 3DR radios). Version on the quadcopter is 3.3.2, version on antenna tracker is 0.75.

    I join the only log file I found, a tlog, but does not seem to contain any useful data.

    The only finding I've made so far is the chronological order in which you have to turn on the various components to establish the links. In my case, if not following strictly this order would make it impossible either connect with mission planner and/or see both antenna tracker and quadcopter in mission planner.

    1-Plug the ground radio module in the PC's USB port

    2-Turn on the antenna tracker

    3-Turn on the quadcopter

    4-Open mission planner, select the com port of the ground radio connected on usb and click connect (To switch between the quadcopter'sview or the antenna tracker's view in mission planner, you need to CTRL+X which displays a drop down box where you should see a list containing the quadcopter and the antenna tracker. Both should be visually represented on mission planner's map.)

    Main goal remains , i.e. to track effectively in a stable manner in yaw and pitch : currently sometimes yaw works, sometimes pitch works, but rarely both simultaneously. Maybe it has to do with my parameters, maybe it has to do with the still very green firmware. Like Trump says : there is something going on and we have to find out ! I hope at least the attached video can help Randy to troubleshoot what's going on ?

    • Developer

      Hugues,

      The .bin file is actually from the copter and the .tlog doesn't show much as you said.  In any case, from the video it's clear the tracker's GPS is not giving good values.  We can see the white tracker icon jumping around on the map.  I think the problem there is just that you're probably indoors so it's not getting a good GPS signal.

      It's apparently possible to hard-code the tracker's location by setting the START_LATTITUDE and START_LONGITUDE parameters.  Set them back to zero to restore the use of the GPS.

      By the way, a nice looking setup you have there, is that from servo city or somewhere else?

      • MR60

        In fact I hardcoded the start longitude and latitude but , as you noticed, the white icon representing the antenna tracker was still jumping around. Is there another parameter to set to tell antenna tracker that it sits on a fixed position (not use his own GPS) ?

        • Start lat and lon are only valid until you have a 3D-fix on your GPS, so simple answer - disconnect your GPS from your antenna tracker. It is useful when you debug your AT at home without GPS and use it in real environment somewhere else.

          • MR60

            thx, I'll try that for in house testing, although,, like Randy said, I should really test outside. It's just that living in a City street, neighbours might call SWAT for a bomb alert lol.

            • I did a lot of my testing using SITL - I just feed data from sim into AT and it tracks my virtual plane

              • MR60

                good idea

      • MR60

        Thx Randy.

        My tracker is a personal build as shown in this video, so that others can duplicate:

      • Developer

        Sorry, Greg's right. The .bin is from a tracker!  The very first "MSG" line shows the vehicle type and version in case anybody wants to ever check this.

        3702735790?profile=original

    • MR60

      forgot the tlog. Here it is.

      2016-02-14 11-03-45.tlog

      https://storage.ning.com/topology/rest/1.0/file/get/3702618177?profile=original
This reply was deleted.

Activity

DIY Robocars via Twitter
RT @DanielChiaJH: Great racing against @a1k0n today at @diyrobocars! Pretty cool to both break sun-9s at the track today I think I got very…
22 hours ago
DIY Robocars via Twitter
Broadcasting the @circuitlaunch race live now at https://m.twitch.tv/diyrobocars Races begin around 2:00pm PT
yesterday
DIY Robocars via Twitter
RT @a1k0n: ran a huge number of hyperparameter tuning experiments yesterday; now I can train a new policy, far with better quality, in 15 m…
yesterday
DIY Robocars via Twitter
RT @a1k0n: Did I get rid of hand-tuned parameters? Yes. Am I still hand-tuning more parameters? Also yes. I have a few knobs to address the…
Monday
DIY Robocars via Twitter
RT @a1k0n: I'm not going to spoil it, but (after charging the battery) this works way better than it has any right to. The car is now faste…
Monday
DIY Robocars via Twitter
RT @a1k0n: Decided to just see what happens if I run the sim-trained neural net on the car, with some safety rails around max throttle slew…
Sep 26
DIY Robocars via Twitter
Sep 24
DIY Robocars via Twitter
RT @SmallpixelCar: @a1k0n @diyrobocars I learned from this. This is my speed profile. Looks like I am too conservative on the right side of…
Sep 24
DIY Robocars via Twitter
RT @a1k0n: @SmallpixelCar @diyrobocars Dot color is speed; brighter is faster. Yeah, it has less room to explore in the tighter part, and t…
Sep 24
DIY Robocars via Twitter
RT @a1k0n: I'm gonna try to do proper offline reinforcement learning for @diyrobocars and throw away all my manual parameter tuning for the…
Sep 23
DIY Robocars via Twitter
RT @circuitlaunch: DIY Robocars & Brazilian BBQ - Sat 10/1. Our track combines hairpin curves with an intersection for max danger. Take tha…
Sep 22
DIY Robocars via Twitter
RT @SmallpixelCar: Had an great test today on @RAMS_RC_Club track. However the car starts to drift at 40mph. Some experts recommended to ch…
Sep 11
DIY Robocars via Twitter
RT @gclue_akira: 世界最速 チームtamiyaのaiカー https://t.co/1Qq2zOeftG
Sep 10
DIY Robocars via Twitter
RT @DanielChiaJH: Always a good time working on my @diyrobocars car at @circuitlaunch. Still got some work to do if I’m to beat @a1k0n howe…
Sep 10
DIY Robocars via Twitter
RT @SmallpixelCar: My new speed profile for @RAMS_RC_Club track https://t.co/RtLb7TcgIJ
Sep 10
DIY Robocars via Twitter
RT @SmallpixelCar: Practiced at @RAMS_RC_Club today with my new @ARRMARC car https://t.co/AEu2hCx89T
Aug 28
More…