Servers by jDrones

Support for Omni Boats coming in Rover-3.5


(ERL) #32

No worries Randy, Glad to help.

Here is some footage i took about a year ago, using ardusub as the code base.

The X frame boat is in stabilised mode, automatically keeping the heading from the last controller input.

I am using a “calibrated” stick to try and change the heading. There is no controller input from myself

If this mode was to make it’s way into rover it would be a great help to me.


(rmackay9) #33


nice video, thanks.

Yes, if all goes well we should have a mode like this coming… basically I think once we add lateral support to ACRO mode it will do what you want… I think… The only thing is that ACRO would also try and hold position if it had a GPS. If it didn’t have a GPS position then it would be just like what you’re looking for… heading hold but otherwise manual…

(ERL) #34

Thanks for the reply Randy.

My reasoning is that I want to take flow measurements and maintaining a heading directly into the flow is important. ideally I want to automate this, but there are times were GPS will not work ( tall trees on the side of riverbank) so i will need to use manual mode.

A Stabilised type mode would help a lot in very low/slow flow and the wind blows hard in the wrong direction effecting the heading. Taking some of the driver error or helping the driver in preforming measurement.

I guess I could turn the gps off if it is not needed for driving manually.

In this video stabilised is on and you can see when the boat changes direction moving laterally the autopilot takes hold of the heading. The end result is very straight clean lateral movement, which is what I’m chasing.
I am only using 1 stick on the controller, lateral / forward reverse.

Any move to a mode like this is a great help Randy, thanks for the continual improvements and efforts.

(Kg Fairbarn) #35

Would be interesting to use a Voith drive with this frame type…

(rmackay9) #36

I’ve never seen this before! It’s a bit like how a traditional helicopter flies which involves changing the pitch of the blades as they rotate. I suppose the complexity is mostly in the mechanical setup itself… the inputs to the mechanical bit may just be forward-back and left-right. Anyway, if someone puts in the hard work to actually build this mechanism, I’m happy to help with the software side 'cuz I think it’ll be far easier than the hardware!

(Kg Fairbarn) #37

Graupner has been making these for a long time but they are relatively expensive.

(rmackay9) #38

OK, so the interface is not difficult to support I think. It would need a 360 degree servo controlling the top bit and then the motor speed would just be another PWM output from the back of the flight controller so not bad.

Thanks for sharing!

(Labomat) #39

I am planing to add Ardupilot support to a rc diving support vessel (model), that is equipped with Schottel propellers - basically propellers that can be vectored horizontall (at 270°). The boat has two set of propellers at the bow and two at the stern (acting parallel). Is there a setup for this kind of layout?

(Reza) #40

Hi rmackay9,

I’ve been trying to set up a frame like this, but have run into issues getting the motors to actually run. I’ve uploaded the software and changed the configs, as instructed. I was wondering if you had any insights into what is going wrong? Does it maybe have to do with what frame_class I am using?

Here are some pictures on the test bench, in case I messed up the wiring somehow.

(rmackay9) #41


We don’t support propeller’s that heading can be rotated around (yet) I’m afraid. I’ve seen some expensive looking research boats that have this so it has crossed my mind to add support. it’s not terribly hard but it’s certainly a few days of effort for someone. Probably the first step is to raise and issue in the issues list so the request isn’t forgotten.

(rmackay9) #42


Have you tried the motors test in the MP? After that a log file is probably the best way for someone to look into this.

(Reza) #43

Hi @rmackay9,

I have just tried the motors test but receive the error: Command denied by autopilot. This is with the vehicle armed. I assume this is the problem I am having, how can I fix it?


(rmackay9) #44

Hi Reza,

Just disarm the boat and the motors test should work. If the vehicle is automatically always armed after startup then there’s a parameter, ARMING_REQUIRED that must be set to “1” to allow arming/disarming.

(Reza) #45

Even with the vehicle disarmed, I am running into this problem.

(Labomat) #46

Maybe it ist already there: I think this is about my issue:

(Reza) #47

@Erl77 do you think you could describe the steps you took in setting up your vehicle? I am trying to do the same thing, but have not managed to get it to work…

(ERL) #48

Hey mate

Im heading out of town for 2 days then will be back. I have seen your posts and have been thinking of what the issue could be.

Assuming you have it armed and your motor assignment correct eg motor 1 set to 34.

Then it might be a radio calibration issue, maybe!!!

I will write a step by step with some photo of what i did to get it going when I gat back.


(ERL) #49

Hello Reza

Sorry for the late reply, I have been away. I hope you have got your X frame boat going by now, but if not I will share what I found with the new revision of the firmware.

I managed to setup my omni boat again, (I use the flight control for different boat setup)

I flashed the latest firmware 3.5 rc1. I then :-

  1. set Frame Class to 2 , set the FRAME_TYPE to “2” for OmniX

  2. set the SERVO1_FUNCTION to motor1, SERVO2_FUNCTION to motor2, SERVO3_FUNCTION to motor3, SERVO4_FUNCTION to motor4.

Now what happens was that the flight controller didn’t detect that it was a omni boat automatically and map the servo functions to the motors.

This may be happening with you, because they are not mapped you don’t get any motor output.

I changed this by just randomly changing all the servo function to a different motor numbers, eg servo1 to motor3. This seemed to help kick off the mapping of the motors. Once mapped i changed them back to the correct order and they stayed mapped.

I hopes this helps.


(rmackay9) #50

We’ve started beta testing for Rover-3.5 now so I’m keen we get to the bottom of this. I think it’s very possible we have a bug because the developer didn’t actually have access to a 4 thruster boat when writing the code nor do we have a simulated model of this sort of boat.

(Ammarf) #51


Does it always fail to map the servo functions?

I think it can’t map them properly when Throttle and GroundSteering are already set, but usually when I disable them, set the FRAME_TYPE parameter and reboot the flight controller, the servo functions are mapped without problems.