Servers by jDrones

Dual-motor tailsitters

(tridge) #362

yep, we’ve been thinking about petrol vectored tailsitters too. We already have code in ardupilot for automatic engine start:
See this example:

right now it can only auto-start one engine, but we could extend it to two. It even restarts the motor in flight if it needs to. We had that happen on an auto mission. The motor stopped (bad fuel supply system), and ArduPilot automatically restarted it and it continued its mission with no operator intervention.

( research air) #363

pretty slick, is there a gen on board? I’d like to see that motor/ starter assmbly if available, and what are you doing about vibration?

( research air) #364

i’m thinkin 1 gas 2 electric

(tridge) #365

there isn’t in this one. We did have a generator in an earlier plane (back in 2012), but we removed it as it really wasn’t helping and was causing some mechanical problems.
For the plane in the above video we were aiming for a bit over 1hr flight and it only needed quite small avionics battery. To change the VTOL motor batteries would have been hard as they are high capacity (8.8Ah of 6S) so it would have taken a lot out of the petrol engine to charge them.

(tridge) #366

we just used a kit for the DLE-35, which is the motor we used. I think this is the one:
it wasn’t really reliable actually. Brushed motor, and the brushes failed once, the terminals broke off twice in cold weather with vibration. We just replaced with spares as needed.

there is heaps of room in the porter, and it only flies horizontally, so vib isolation is easy. We used an aluminium plate suspended on small cubes of dubro 1/2" foam, with another layer of foam blocks above that then pixhawk1 above that. Worked fine, but quite bulky. I can send photos if you like, but I wouldn’t say its a great setup. Worked for what we needed.

(tridge) #367

@tilt btw, can you send some close up photos of the motor tilt servo mechanism you used in the illusion?

( research air) #368

here is one I took today, if you want more let me know, it’s off yellow, not very aerodynamic

(kd0aij) #369

Here’s another view of the Stryker’s transition from FBWA to Qhover. The nose drops in the middle of the transition due to the Z controller killing both motors to stop the climb. Will soon be trying Leonard’s patch to give priority to attitude control:

( research air) #370

( research air) #371

2024t3 .032 alum.1/4 " x1/8 BB, nylon drag washers 4x40 screws

(tridge) #372

thanks for the photos!
I’ve pointed Jack Pittar (the CanberraUAV lead builder) to this discussion. He’s working on the design of our OBC TVBS now.

( research air) #373

great Hi, Jack ! OBC?

( research air) #374

never mind, outback got it!

(lorbass) #375

In the pics I see you are using folding props.
If you have havy vibrations, may be due to this type of Props.
On my Quad 650 I had to go back to standard props.(15x5.5)
And they need 10% less energy than the folding ones.
Left: Standard Props ------------------- Right: Folding Props

( research air) #376

Hi, who’s props did you end up with ? looks like a big differance,but also i’m cheep and tried the 15" carbon from china, not so good.the mpc 14.47, mpc ‘s worked but not as good as the tarrot 15"

(lorbass) #377

So you don’t have havy Vibs?
I used this one

with this “nice” holder:

And even balancing with this:
was not possible because moving blades made troubles.

Astonishing is that the Y-Axis is dramatically high.

The target was, to simplify the transport.
Where did you buy it?

( research air) #378

direct from tarrot, also got the tube mounts in the pic.[quote=“lorbass, post:377, topic:15302”]
And even balancing with this:
[/quote]wow,…that one just melted my brain,

( research air) #379

ask Tridge ,he’s working the logs,but they seem ok to me, I have never had good luck with carbon props ,these are plastic. but if you get into oscillations in pitch, they break at the root weak point

( research air) #380

Jack… some pic of my simple build system 3/16" foam board 1/4" sticks and lite ply hard points
top is about 1 1/2" shorter with 1/16" cap strips top & bottom, c/f tube spar, very quick build

( research air) #381

done, logs on the way, google drive and youtube video