So, I've got this slightly used and abused APM1.4 that I want to try putting on an airplane because it won't fly a helicopter anymore. And I've got a 10 year old 80" Hangar 9 Cub ARF that I haven't flown in 6 years, and I'm not particularly attached to, so I figure it would be a great candidate? It's got a Saito 56 4-stroke nitro engine that has always been reliable and efficient. I don't think it's ever flamed out once after adding an on-board glow driver. This is a balsa, ply and Monocote model, not foam.
I read through the Wiki, but have a few questions:
1. To mount the APM, do I need to worry about vibrations from the motor? This is a problem with my helis, and I'm not sure if I need to worry with the airplane. The Saito does vibrate a fair amount given it's a 4-stroke. What would be the best way to mount it?
2. Since the fuselage is balsa and ply covered in monocote, can I just stick ALL the electronics right in the fuse, antennas and all? Right now it has a 72MHz receiver with the antenna inside, never been a problem.
3. Currently the model has a 4.8V NiCad 800mAh battery pack. Can I power everything with this, or should I definitely go ahead and retrofit with a 2S 2200mAh Lipo and BEC? I'm pretty sure using that NiCad is high up on the "bad idea" list, but just thought I'd check.
4. Ultimately if this worked out, I'd try to put a larger Aux fuel tank under the CG for longer range. With the huge wing, the airplane has plenty of lift, but I wonder about the power. It's well over-powered for a scale Cub in it's current configuration, but can't pull vertical (loops are no problem). I have no idea about how much weight it could actually take up. I'd plan on using some camera gear, etc, as well.
5. Is there any Glo Driver function in the AP software yet? Currently I have a mechanical setup with a microswitch that comes on at low throttle. I'm not sure if there's any point replacing it, but just thought I'd ask.
I am also interesing in doing something similar to this with a nitro plane. I plan to use the APM 2.0. board though. I would sure love to hook an autopilot up to the nitro plane. I also plan to use GO PRO HD camera with it. I was wondering. Can you post step by step instructions, or better yeta youtube video (similar to the one below) on you get the APM into the fuselage, installaiton of bigger fuel tanks for ranger and how it worked.
I am plannin to use the Nextstar select trainer. I am not sure if i can fit a bigger fuel tank inside. But i would like to check the space inside the fuselage to see if i can setup the APM.
Well, I've got this thing prepped using my APM2-Rx all-in-one. The APM2 is mounted on rubber vibration dampers. I had to redo some of the wiring as the connectors had corroded. At first I thought the servos had gone bad, but I did some troubleshooting and that was it.
I'm a little nervous about flying this thing with Arduplane, as I'm not sure how it will go. The setup seems SO much simpler than a Heli, I feel like I'm missing something!
Success! She flies beautifully, and the stock params aren't too bad either. I guess I need to figure out the navigation. The loiter isn't great, but I think I just need to open up the radius. But so far so good!
The engine is running fairly well, but I wouldn't try a long distance mission until I get the onboard glow driver working again. I had one flame out.
The 4 stroke vibes seem to cause a bit of "leans" on the ground, but don't seem to affect it in flight. I'll go to softer mounts.
Just back from the field. A few more notes while I remember:
I can't remember how big the tank is, probably 11 oz or so. But it just goes on forever. I would come down after 10 minutes of flying and guys were laughing because it only used about 1/3rd of a tank. So 20 minute missions would be no problem at all. And I was using a 2S 2200mAh pack, through a MegaBEC 8A linear regulator, and seemed like it could go all day. I had the system turned on for... 2 hours or more and still had TONS of charge left.
The FBWA mode was perfect with the stock PID's. Maybe a bit slow, but I don't know if that's the way it's programmed. I'd call it "scale-like" in the rate that it did things. Is that too slow? Should I turn up the PIDs?
The Loiter mode didn't work so well, it seemed like it wanted to do more like figure 8's. It also seemed like it wanted to go WAY too slow. Kept throttling back and just flying too slow. I was just about to start working on that when the Xbee crapped out mid-flight. Not sure what the problem is. Not sure if it's just bricked (strange to happen mid-flight). Or did the vibes kill it? We'll see.
Anyway, it was an enjoyable experience compared to Arducopter as, for the most part, it just worked.
Oh, and the all-in-one didn't work as well as I'd like from the perspective that the range seemed fairly short. I was getting RSSI warnings just about the distance I'd normally fly at. I'm not sure if that's normal, but I wouldn't think so. Actually, I wonder if it's because I was using a transmitter tray, and the Tx antenna ended up kind of pointing right at the aircraft, which IIRC, is not good, it should be vertical? I also have the higher gain Tx antenna I can try.
The plane flew just beautifully. I asked the club pres if he'd take it up for me on the first flight, as it'd been so long for me. But he was nervous flying a Cub. They have a reputation for being sloppy fliers. Anyway, so I went for it. No problem at all, just like riding a bike. After a few landings, they just beautiful. Not 3 points, I could never really do that with a taildragger. But the big plane flies SO much better than the little foamy I was messing around with.
Whats the difference between APM 2 RX all in one and just regular APM 1 or APM 2.0 , 2560? Also could you post step by step photos of your plane and how and where you mounted the autoplot. How you loaded it , e.t.c. I would eventually like to repeat this : http://en.wikipedia.org/wiki/The_Spirit_of_Butts_Farmwith with a go Pro camera to record this nice trip.
if you did a video and put on youtube that would be great. I know there is one guy that did a video using the APM 1 setup. But it would be a nice dream to watch an DIY gas rc plane fly on its own. I have not bough the plane yet, I am looking at the nextstar select but might use your cub if a 50 oz gas tank can fit in it.
Well, there's not really much difference between a regular APM and the APM2-all-in-one, other than the obvious fact that the Rx is mounted directly on the APM2, feeding CPPM into it so there are no Rx wires at all. The range with this setup appears to be quite a bit shorter than I would like. I'll be trying to improve that.
Man, your link to Spirit of Butts led me down a rabbit-hole yesterday, ended up doing a lot of reading on the Aerosonde UAV, with particular interest in the fact that they used a modified hobby 4-stroke engine, not that unlike the one I have on this airplane!
awesome Im going to pick up a big cub so i can fly on windy days chould you post some pics of your setup thanks
James, I wouldn't necessarily recommend picking up a Cub as it's not really ideal for the role. I just used it because I had it.
There are plenty of more modern designs available that would probably be suitable. This one is interesting:
no I was geting one allready 8foot wingspan with 2 cly 4 stroke 300 bucks Ive got radians skywalkers ogar x8 easystar 40s 60s helis quads they do not like the wind I want somthig I can fly on less than ideal condtions thanks though
Ok, sounds like you know what you're doing. ;) Just didn't want any newbies to think this was a good first airplane. It's not, really.
I dont know about that ; ) if I crash this one they will haft to shut down the airfield to clean up the mess
I think one thing that is very important is soft mounts for the APM. I had good results with my ring-mount dampers, but if I try it again, I'm going even softer.