P2: Connecting a servo to the F2 Naza problem

[paturoa]

Making some interesting discoveries. With my P2 and v3.8 of the phantom assistant.

I go to the advanced gimbal tab and watch the signal on my oscilloscope. Basically none of the settings make any observable difference. The gain did not change how fast the pulse width changed, the horizontal limit made no change (as I would have expected) and neither did the vertical limit slider. Though after reading the text I fail to see how a single slider can change the upper AND lower limits. Suspect it is actually changing the mid point rather than the limits.

I could see the pulse width changing properly from 1 to 2 ms as expected.

This includes ticking and unticking the FPV mode. When I tilt the P2 it still changes the signal to maintain the horizon.

Made me think that the settings I were changing were not being updated into the P2. So I repowered the P2 and no change.

 

[paturoa]

Sent off a support query to DJI yesterday morning asking how I change the freq. No response as yet, how long do they normally take to respond?

 

[CityZen]

Take a look at that thread I linked earlier; I found the utility you might want to try out.

 

[paturoa]

Take a look at that thread I linked earlier; I found the utility you might want to try out.

Awesome!!!!!! Solved. I unpacked the tool and ran it.

https://www.dropbox.com/s/icz90nramn56mf3/phantom2-tool.rar

I then selected vision mode and quit the app. When I then opened the phantom assistant v3.8 app the other gimbal config screen was available. So I changed the freq to 50 hz and quit the phantom app. I then went back to the tool and changed back to the other H2-3D mode and when back at the assistant the 'normal' screen was visible. Lots of testing and the cheap servo works as expected.

What I'll do next is play with the settings to get the servo range I need to actuate a hook mechanism for the fishing line connection.

Next step is to build a latch system and test. I'll post another thread for that build.

MEGA bling to CitiZen....

 

[N017RW]

Cool,

So for the record what is the setting(s) or change(s) required to make a 400Hz servo work on that port?

 

[paturoa]

Cool,

So for the record what is the setting(s) or change(s) required to make a 400Hz servo work on that port?

I've not played with that as I don;t have a servo that runs at that freq. My answer would be go through the same routine and change the freq to 400hz (as opposed to me changing it from 200 to 50 to get mine working)

 

[N017RW]

Gotcha.

I may have lost focus on that.

 

[hitch93826]

I am using a P2 with gimbal and trying to create a drop hook also. I have followed the steps above but I cannot get my servo to travel more than 90 degrees. Also, I want the hook to stay forward and when i move the X2 I want to servo to move 180 degrees and STAY THERE. but it always comes back to the center point. If i try to adjust the limits to get the hook to stay forward (level with ground) then the servo does not have full range of movement to go back. please help!

 

[georgevfr]

I have the same problem.Can someone give directions what to do ?

 

[Mike Crago]

Hi, new to this forum.

My dad has purchased a P2 and I've ended up being the tech help. What he wants to do is use the P2 to drag out a fishing line with multiple hooks beyond the surf break and drop it, then return to home point.

So he's bought a Tower Pro SG90 micro servo to actuate a hook system. The guy he bought if off wired a 3 pin lead from F2 on the Naza. I went into the P2 App and calibrated X1 and it all seems to work properly.

Next I checked the pins from the Naza and pos 5v is centre with signal and earth either side. Next is I double checked the servo pins and specs and that all looked OK.

So I plugged it together and turned on as per normal. Moving the gimbal tilt lever on the back of the controller moves the servo but here is where the problem(s?) are.

• The servo is supposed to rotate 180 degrees but only gets about 90.
  
• It doesn't move proportionally to the lever. For a lot of the range nothing and then some jumps.
• It will often vibrate when in position.

So I got out the trusty meter and double checked the pin outs, all good as spec. Then I noticed that the servo was warm. So monitored the current on the 5v supply and it would pull about 700mA max when it was vibrating and bugger all when not. 700mA is way too much for a no load situation on a micro servo.

So after a bunch of searches tried various settings for the advanced-> gimbal -> gimbal config settings and that made no difference. Then spent several hours googling and reading everything. There is one other thing I've not tried and that is to use a ferrite ring but I don't think that is the issue.

Anyone else got a 3rd party servo working properly? Am I using the correct wiring etc??

Cheers Brian

edit: I'm currently suspecting that the prob is the servo itself and will try another one tomorrow (if I can find a cheap one)

Brian, did you figure it out. I just purchased a phantom 2 and my plan was to add an external servo for a remote drop system. I tried plugging into F2 port and the servo shakes and buzzes. Would like to know what im doing wrong.

Thanks
Mike