Servers by jDrones

Single servo aims the aircraft antenna

I want to use already-available data (osd “home” arrow?) to train a moxon antenna on board the aircraft at the home position. Tracking data- home position etc. could be compared with aircraft heading to obtain pointing data for the antenna towards home position (assuming ground station is at home position).
I’m not a coder so will appreciate advice from anyone who sees the big advantage of this proposed device. Range is powerfully limited by the need to use omnidirectional antennas on aircraft, or any controlled device.
Sevo is available, but will need to be limited to 350 or so degrees. at which point it will retrace to the other side of compass to prevent the need for a commutator, with all it’s problems. could use a moxon or almost any wire-frame directional antenna. The more accurate the pointing, the more gain that can be built into the antenna.
Thoughts, anyone?

sorry that I have nothing to offer, other than my interest in the same thing. I can’t understand why there has been so much development into ground stations but none into this. all the pieces are there.

Its a mystery to me also. No way this could be hard, for a competent
coder. Wish that was me.

I did it once with my rover and an Alfa directional wifi antenna. I mounted the antenna to a 360° sail winch servo (with a long enough extension cable) and used the camera gimbal function to point the antenna at the home location. It worked well enough, but I get around 200m wifi range with an antennatracker with dual directional antennas and omni antennas on the rover, so I did not follow this idea any further.

Now that longer range RC, from a few manufacturers, is relatively inexpensive tracking hasn’t gotten much attention.

Well, I can say that this isn’t an “AntennaTracker” issue :slight_smile:

This is a “mount” issue.

What’s needed is a new MAV_MOUNT_MODE enumeration entry,
MAV_MOUNT_MODE_HOME - and a trivial amount of code to support it as we
already support pointing a mount at a specific GPS location.

We already support most of the existing MAV_MOUNT_MODE options:

If someone is in a position to actually test this, I can knock it up over
the next couple of days.

If you stop to think about it, the use of high-gain tracking antennas on
the airborne end of the link could reduce the need for high-powered
transmitters, of the sort that are suddenly popping up all over the
place. These things walk all over the gps, make for sevo jitter and a
host of nasties. An airborne beam antenna just whips up on many of these

I haven’t had those issues with the Frsky R9 system but I take your point as some have. I’m using it now on most models; Multirotors, Planes and a Rover. I run them all at 1W adaptive power.

If I understand correctly I may be forced to test something like this in the near future.
I’m running a boat and have to aim a Point to Point antenna back to the shore for a separate control system.

I’m gutting and hacking a TracVision M1 antenna tracker to point a network radio back to the shore. I’ll be installing Pololu tic stepper motor controllers to make the system multi turn

At the moment i am pretty new to everything pixhawk/ardupilot/mavlink so my plan was to just install a second flight controller and give it a “fly to here” that it will never be able to reach. (hence the multi turn/ continuous rotation requirement)
However I would love to just be able to run a couple servo lines up to the antenna. and accept that the network may get lost momentarily during “unwinds”

I think generally the struggle I have had with this type of system is dealing with the fact that in reality you need a beefy servo of greater than 360 degrees of movement. The stepper motor solution could potentially solve it but it would be much better if it were close loop controlled. I’m not sure if the Tic controllers have closed loop capability it would be amazing if they did.

Anyway Sorry if I completely misunderstand this post. I feel like I have no idea what a lot of the terminology on this forum is but I’m slowly getting up to speed.

If we are talking about the same thing and you want someone to test it on hardware let me know. I’ll be building it all anyway… pan and tilt

Wonderful.Thank you very much. And you are quite right- the most logical way to approach it is as a mount issue
I think it’s worthwhile to keep power out as low as possible on the link, from either end.
The less power we use the less likely we are to walk on the toes of other users. As a long-time ham, I can asssure you that the ham community is quite protective of their perceived turf.
I had in mind a simple setup- a 360 degree servo, on 1.3G with a small wire moxon or 3-element Yagi, using only the pan feature. But I’m not the tester you need, unfortunately. I’m still swamped with getting a little ZX-84 in the air.

Darrel, I think you got it-- that’s pretty much what I had in mind. In my case the transmitting antenna would be quite small and light – a 3 element yagi or a moxon on 1.3G, so you’re tackling a bigger beast than I am. But same principle.

As I think about it more carefully, pan and tilt would be the best way to do it. But small, lightweight 360 degree servos are hard to find- most have been modified to provide motion to a wheel, or something similar.

I hear you on that. I’ve looked at some off the shelf brushless camera gimbals that go to 330 degrees but nothing that goes the full 360+.

It is something I could build but I would rather just buy.

Though if there is more interest in something like this I’d be happy to start selling them… Or even just some conversion hardware to hack regular brushless gimbals into “antenna on pointing mechanisms” (the key words I eventually found out)

Servers by jDrones