Not 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.
Replies
not necessarily. I find that cheap m8n's are much worse than old lea-6h. Only a few manufacturers were able to shield/filter unwanted frequencies well enough on m8n and those units are sold for about $90-$100, while performing marginally better than leah-6h for $50
I have a bunch of lea 6 and neo 7 gps's here. I can try some of them and see if they are any better.
Jeff,
That looks to be about standard -- I'm getting similar results. Since my drone is far relative to the tracker, the GPS noise isn't too big of a deal, but it can be a problem if your vehicle is close to the tracker (worst case will be if it's right over the tracker in which case the tracker will be all over the map). One option is to disconnect the GPS and specify the HOME position of the tracker via APM parameters. Since your tracker won't be moving, then you'll be 100% accurate!
It would be nice if the code running on the tracker had the ability to significantly average the GPS readings. For most users, the tracker does not move -- so heavy duty averaging should eliminate the GPS noise you're seeing.
Is there a procedure that could be followed where the GPS is used to see the map and then set tracker home without disconnecting the gps? Or would the GPS have to be put on a switch of some sort?
Here is one of my planes running the same GPS. Higher hdop, lower sat count, much greater accuracy and no wandering.
Keith, when it doesn't start up and just sits there any chance you could post a dataflash log? And when it does successfully work - preferably 2 minutes later with no changes what so ever and just power cycling post that log to?
Thanks, Grant.
Grand, would you mind sharing, if you know, if servo_type affects only pan axis or pitch as well?
Thank you!
I'm probably missing the obvious but servo_type where? Is that a parameter setting that I am missing?
Thanks, Grant.