Arducopter

[porscheaddiction]

Hey Rob I thought I would start a thread on here instead of hijacking someone elses.

I have been looking at as much information as I can find on the system, I am thinking about putting this system into my new gasser however I still only have flybared helis, Is flybarless absolutely required? I noticed a few youtube videos especially out of the UK where the helis had fly bars and they seem to be flying just fine with arducopter. Purchasing the system boards I noticed a few different options I seen bare boards as well as completed encased boards. I seen sonar boards is it required to have? I also seen 2 GPS options one built in and one cost extra, What is the difference and does it justify the difference in price. What options and board are you using yourself? I also seen in most youtube vids that the pilots had their laptops with them, Does one need the laptop at the field to use arducopter just as a stabilization system? I know for testing and setup it would be needed, I am only interested in two functions mainly, stabilize and RTH. I have no intention of using it to fly way points. Is there anyone that you know of that is successfully flying a gasser or large nitro with arducopter?

Thanks
Chris

[R_Lefebvre]

Hey Chris,

I actually don't live too far from you.

No, nobody has used Arducopter on a gas/nitro heli as far as I know. This touches one of the bigger problems with the system, in that it doesn't have any built-in vibration damping. We use digital filtering, which actually helps A LOT, and is a recent addition. But nobody has tried it on a gas heli.

I have flown it, before the digital filtering, in an 80" J3 Cub airplane with a Saito 4-stroke that shakes pretty hard. It did fine, but I was able to use very soft vibration dampers which you cannot use in a heli because you need the responsiveness of feedback for a heli.

So, it's an unknown. I would recommend you or anybody else to play with the system on an inexpensive heli before attempting on anything expensive. Both because of the possibility of bugs, and because it is complicated to get the system running. The problem is the system is so powerful and flexible, there's a lot to learn.

But, I think that the system could be made to fly on a gas heli, you would just need to engineer an external vibration damping system.

I've actually made the decision recently to hold back the heli code a bit compared to the multi-rotors. I just can't afford to crash test the latest stuff on my helis anymore.

Normally we go in cycles where a new code is released instituting new features or greatly improved features. We go through a lot of beta testing, but still, some things escape us. Usually there is a minor revision a few weeks later with some bug fixes. I'm planning on not doing releases for the first stage. I'll let the MR guys crash test that a bit, and only do a heli release in tandem with the bug-fix release.

In a few weeks hopefully, we will be releasing a new code that has VERY good inertial positioning, but you won't see it on helis until a few weeks later.

Arducopter flies fine with a flybar. That's actually what I was using until recently. No issue there at all.

So, on the hardware:

What you want is APM2.5. This is the lastest APM. It comes with a case. If you've seen them without a case, that is from the past, or maybe if people were buying APM2.5 right after it was released, the cases weren't available yet.

I typically don't use the cases anyway. I do crazy things like this:

http://diydrones.com/profiles/blogs/...-rx-all-in-one

Sonar is available, but not required, and honestly for the most part is more trouble than is worth. We used to use it to improve alt_hold performance, but it's not necessary anymore. We now only use it for ground-tracking flying, true AGL instead of ASL. But it can cause problems and I wouldn't suggest it for a newbie.

For the GPS, you must get the higher priced Ublox GPS. Don't even bother with the Mtek. If you can't afford the Ublox, just opt for GPS delete, get nothing. The Mtek is OK for airplanes, but on copters, it's more trouble than it's worth. Maybe it will work better when we have intertial navigation going but, I dunno yet.

You should also plan on buying the external magnetometer. I wish this was built into the GPS, but it's not unfortunately.

Laptops are only strictly necessary for tuning, and running waypoints. But myself, I would want something even if I just wanted to do RTL, just to make sure the Home point is set in the right location.

There's been a fantastic recent development called Andropilot you should check out. You can plug the telemetry radio into an Android phone, and do all the basics. Super simple. It doesn't work on all devices, so you'll have to check the list.

There's no Apple version, because it's so hard to develop for Apple, especially if you want to plug something into it.

[StraightUp]

Rob,

That sounds great, I've been holding off on the Arduino platform but I think I should djump in and get my feet wet

Was looking at the site you suggested and they have 2.5 with power measurement (volts, mah) does that mean that the Arduino board also works as an OSD or can easily output to and OSD?

As for crash testing, If you like I have a few spare 450 clone parts I could send you, frames, skids, tail rotor, booms. to help you with the testing, let me know

As for what to buy. I'm lookign at this http://store.diydrones.com/APM_2_5_A...t-telem915.htm

and then the magnetic compass that you were talking about would that be http://store.diydrones.com/HMC5883L_...hmc5883-01.htm

Would that be all I would need to get going and load the heli code on there?

Cheers,

[R_Lefebvre]

Yes, absolutely, it can also drive an OSD. That system is called minimOSD. Works well. I just plugs right into the APM, a nice software setup on that one.

The power monitor system is nice, but I have never used it myself. I don't bother on my 450 since it's mostly short range, and honestly I don't want the complexity. It would be nice to have on the 600 heli, but can't handle the power.

What I'm actually working on right now is allowing for dual voltage monitoring. I like using a separate 2S LiPo for servos and the APM. I need to monitor that, and the main flight battery.

For the parts, I'm actually doing OK I think now. I don't crash a lot anymore. And when I do, it's usually light. Well, I mean, boom, tail shafts, main shaft, main blades and bearings are what I go through. I've never broken a frame. But like I say, it's going pretty good lately. I just ordered some good servos for the 450 because I was using $7 servos and they're pretty sloppy. Ordered some KST DS215's for it yesterday, and a new Tarot swash. The Align swash is pretty crappy, I heard the Tarot might actually be better.

I was pretty bummed because I had made a really cool Octocopter from scratch, and I just completely wrote it off on the second flight. 90% my fault. I let the battery powering the APM get too low because I was concentrating on tuning too much. That's why I want to get dual voltage monitoring going. So, obviously user error, but I think we could have managed the situation better. I've modified the code that it will now give a low battery warning (flashing lights) if the APM Vcc goes below 4.5V. And then I'm going to make it so that it forces an auto-landing if it goes below 4.0V. The board was alive until it got to 3.08V. And them I'm also adding support for a second battery voltage input as I mentioned.

I've said it before, but that's the extent to which we are taking things. Trying to make it as idiot proof as possible.

Yeah, that looks like the right APM if you don't want the GPS. The telemetry is included and it's just invaluable.

And that's the right compass too. The best place to mount it is back on the tail, but this can be a problem for a 450 because of CG.. I mount it behind the anti-rotation bracket on top of the tail boom on the 450. It gets a little mag interference there, but it's not too bad.

And, yeah, I think that's everything.

Well, I guess there's also the mounting you have to worry about. Hard to find a place to stick the unit on a 600, impossible on a 450. You'll need some kind of plates. Not sure if you can see in my vids what I did, I'll have to try and get some pictures. There's these available too:

http://store.diydrones.com/product_p/ac-0004-20.htm

What I did is very similar, just a little sleeker looking.

Oh, and the side-entry APM might be a little better for a heli. You have to plan out where you're going to put it, and buy the right case.

http://store.diydrones.com/APM_2_5_N...2-telem915.htm

The only difference between these is if the input and output headers are straight up, or right-angle. For mounting on the little 450 sub-frame I linked, I think side entry is better.

[Newfie Pilot]

Rob,

I have been eyeing this system as well for the last several days. I was thinking of putting it on my Trex 550 FBL in place of my Skookum 720. I was thinking of getting a GPS for the Skookum, but then I saw the Ardupilot for much cheaper. I do not do 3d, just scale flying for me.

I was wondering about the mounting. I guess that it has to be mounted flat? Do you thing that there is enough room in the frame of the 550 to mount it there? Do you happen to have the dimensions of the board? Also, for vibration, would it be possible to mount it with Zeal? Or is it mounted like a regular FBL controller, for which I tend to use 3m double sided tape?

Jim

[R_Lefebvre]

The thing people must understand is that it is NOT a good 3D controller. At all. So if you replace like a Skookum, and want to do any kind of acrobatics at all, you'll be disappointed. It flies really good up to 45° from level. The ability to flip is really limited. Hopefully we can bring this soon, it just hasn't been a priority.

For flying around like I showed in that one video with my 450, the one where it's actually *flying around* it's really fun and easy to use like that.

Up until now, it has been required to mount it flat. Tridge recently made some code so that you can mount it any way, but I'm not sure if that works in 2.9.1 yet. I don't think so, but this is probably coming soon.

Mounted flat the naked board *just* fits between the frames on a 550/600. I'm not sure if it will fit in a case. This is something that I've kinda struggled with. I've done various things, but none are a great solution I can show. I'm actually building a 550 right now and am not sure what I'm going to do yet.

In the past, I've actually custom machined a plate which replaces the Rx mounting plate on my 600e, and it extends back out the rear of the frame. Put the APM on the top of that, and the Rx on the underside. I think that's the best I've come up with so far. But the 550 is not so easy because it doesn't have an Rx plate like that. I'm probably just going to stick it up on top of the tail boom block.

Here's the dimensions:

http://stuff.storediydrones.com/APM_v25.pdf

Pretty soon, the PX4 will be ready for general use. It's a bit more expensive, but it has a much better processor. It should allow much more capability later on. It's also smaller and will be easier to find room for.

http://store.diydrones.com/category_s/63.htm

Vibration damping is pretty important for the board. Especially now for the inertial alt-hold, and the upcoming inertial navigation. I've had luck just using these little blue vibration mounting grommets in the mounting plate under the APM. But I *think* that just typical good gyro mounting techniques should work. The main thing is to make sure it stays aligned with the frame. If a tail gyro rotates a little bit, it's not a big deal, as long as it's flat. With a FBL controller or APM, it's more important to have it aligned. So just sticking it on some zeal, with a strap over the top, I don't think that's going to work too well.

We used to have a much bigger vibration problem, they weren't even flying straight unless the heli was PERFECTLY vibe free, but that's not much of a problem anymore. Still, if the heli is vibrating a lot, you'll have problems just flying straight. But it's much better now with the digital filter. Now it's OK, as long as your blades are balanced, and the bearings feel fine by hand.

[porscheaddiction]

Thanks for the reply Rob as crazy as it sounds I'm still interested in its use for a gasser I found a few youtube vids of a couple being used in gasser helis however no real flight videos of it.
Here is something I found what do you think of these for isolation of the board?

http://www.amazon.com/Ignition-Elect...1087544&sr=1-2

Apparently they are the size of a pencil, I got the idea of searching for vibration damping due to my gasser boats the engines are mounted with vibration dampers and they work well in the boats. My idea is to mount the vibration mounts to one of the radio trays mount a flat pane of acrylic to ontop of the vibration mounts and mount the board to the acrylic.

Just toying with ideas right now as the available commercial units have big price tags and Arducopter can offer alot more.
where abouts are you anyway Rob? you can PM it if u like.

Chris

[Valkman]

I enjoy reading your posts. Lots of information to be had. Have you looked at installing one on a Chaos 600. The frames are wider so the unit might fit ok. I am not at home at the moment but if you want I can measure mine for you.


Edit....55mm