AH-6Z Littlebird Night-Ops build project

[Malc1]

I can't believe that I have missed this thread previously and have just read the whole lot.

I really have not seen such quality and pure modelling skills before anywhere.

This is a work of art....

[Zeeflyboy]

Thanks malc!

Not one for the scale purists it would seem, but I think this project has appeal to the general heli/fun-scale/FPV population... I'm glad people are enjoying following the project!

Got a message from Anthony last night and he has finished the 16ch firmware. Channels 1-12 are as normal, and 13-16 are at 1/4 rate. This means they only update their position once every 4 frames - so given a 38ms 16 channel frame from the taranis for example, that would mean an update every 0.152 seconds - perfectly acceptable for light switches etc... so depending on whether you hit the switch just before a refresh or just after, the delay would be between 0.038 and 0.152 seconds before the action was updated. The advantage of doing this is that it only adds 2 bytes to the RF frame, which is negligible.


He is dropping the kit back today so I will get to have a play.... Assuming it works as intended it should be very straightforward. Just set muxed PPM to one of the output pins on the RX and then channels 12-16 on the remaining pins. Channels 1-7 get broken out on the mechanics by the 8 channel decoder while channels 1,2,4,6-11 get broken out by the 12 channel decoder in the cockpit.


So just to complete the picture from the post above, here is the other side of the frame... as you can see I have braided the servo lines to reduce RFI and where there are servo extensions I have heatshrunk the connection to prevent them coming loose from vibration









and here she is all ready and waiting (complete with 2kg ballast for CG and fuselage weight simulation, and temporary tail support rods since the tail is normally supported by the fuselage). Once I get the transmitter back I can go through the Ace One setup and see if I've installed it all correctly. If no problems arise she'll then be ready for her Ace One testing program!

[wheredidthetailgo]

Good luck with the maiden, I doubt my fingers and thumbs would stop shaking long enough to get it into a hover and that is without the fuse in place. Your a brave man

[Zeeflyboy]

technically a re-maiden I suppose... at least I've seen the thing fly before so I know it obeys the laws of physics lol.

[Tim Procter]

In all my years in this hobby I have never witnessed such a fantastic scale as you have here.

You sir are a genius in my eyes and the extensive work you have put into this project leaves me in awe.

Building kits out of a box is one thing, this is mind blowing.

Very well done sir.

[Zeeflyboy]

Thanks tim! You are all so very nice lol.

did some setup earlier on 1.48 and everything was working (12 channels).

Installed 1.49 (16 channel) just now and that all works - I can control 16 channels just fine... But the Ace One won't power up the servos.

Plug in a Jeti rx and it powers up fine. Plug back in the EzUHF, nada.

BUT, all channels report fine in the Ace One software monitor...

Brain exploding.


EDIT - won't initialise with the longer 16ch frame rate. Put it to 12ch and it comes to life. Humph.

[Zeeflyboy]

AH-6Z Littlebird Night-Ops build project

This is a problem... DJI seem to have arbitrarily set it to not initialise with a longer frame rate than XXms despite the fact that it can see the channels just fine and reports them in the monitor.


There are only 2 solutions I can see to this...


- Either run 2 rx's (which means more antennas and wiring and space). One rx outputs a 12ch ppm stream which works with the ace one, while the second outputs the auxiliary channels.


- Option 2 is completely custom ppm decoder hardware for the mechanics that will double the pwm output frame rates by playing the same frame twice... That would make the Ace One see a frame rate of 17ms rather than 34ms and hopefully keep it happy.


One step forward, 10 steps back...


I'm going to play with it at 12 channels for now - at least that lets me get some flight testing done with the Ace One.

[Zeeflyboy]

So I was discussing with Anders about the possibility of using the Channel wizard as this custom decoder and he mentioned that it already has a fixed PWM output refresh rate of 50Hz.... So Ka'ching I thought - that will solve the problem.


However it also occured to me that perhaps the 12 channel decoder also sets it's own refresh rate while the 8ch is dependant on the incoming PPM frame. I pulled the 12ch decoder out of the eurofighter cockpit and just hooked it up to test. It works! Ace one initialises as it should when using this decoder - it must have a fixed PWM refresh rate.


So I now have a fully functional 16 channel native EzUHF solution. Need to do some testing just to make sure it's all behaving but wow that's great news... I was getting a bit annoyed with the setbacks.

[ianmat]

I'm not sure I understood any of that!!! but it's still an awesome thread!!

[Gazzer1uk]

I put my intelligent face on, and said uh huh in the right places I think! Yes, those so close complexities are proving quite considerable for you but it doth seem progress is happening. Continued good luck and the resources and brain power you have put into this, I truly hope give the appropriate satisfaction when them blades start whirring....... truly a considerably interesting project.... How the hell are you going to top this?

[Zeeflyboy]

How the hell are you going to top this?

A turbine? lol... I don't aim to top it any time soon!

Sounds more complicated than it is - if you know what ppm is and what pwm is then it is all very clear. If you have no idea what those two things are then it sounds complicated lol.

So unfortunately the world is ending. Been nothing but rain and storms all day... back to work tomorrow with long days all week as well. No flight testing any time soon


However I did mount my new ppm decoder (minus front cover just at the moment) and I came up with this temporary EzUHF mount for the test flights.












If anyone is interested in buying my Naza-H + GPS then shoot me a pm by the way.

[Gecko501]

I hope that when you finaly get the bugs sorted you will have somebody help create an equaly awesome video of your maiden flight... multiple cameras and angles.... hell knowing how much you have put into this you could even compose your own music god only knows you capable ha ha

[buzzbird]

Thanks malc!
Not one for the scale purists it would seem, but I think this project has appeal to the general heli/fun-scale/FPV population

Hard to know what more you could do for it to appeal to "scale purists." It's a fantastic job you've done.

[Zeeflyboy]

Oh you'd be surprised...

I have seem comments regarding the lack of scale authenticity. The GPS pod on the back for example, the FLIR pod not being scale in order to accommodate the camera, the registration being a civilian designation rather than military (which would not have the "N" and would simply be a series of numbers), the fact that "U.S. ARMY" should be black... I could go on lol.

Point is that whether you think it is well made and looks cool or not, it is not true to scale... For that reason I guess it'll never really appeal to the scale purists.

Personally I never set out to build a super scale heli. If it looks cool then that's good enough for me.

Gecko - yeah I have mixed feelings lol. On the one hand I want to show video of this thing as soon as possible. On the other I'd really like to spend time getting footage and put together a really good "reveal" movie with onboard, ground and air to air footage.

We'll see. Need to get it finished first...

I've just spent some time setting up the ESC and checking the control system - looks like we've finally cracked it as I can't get it to glitch with this new setup.

[HeliMonkey]

So Z, when will they be on sale to the general public. I assume this is just a prototype and you will be building them for sale in the hundreds? Offering them to forum members for the same price as a 450 kit is really just too kind, you sir are a scholar and a gent!!! lol














crossing fingers