Replies to This Discussion

DeveloperPermalink Reply by R_Lefebvre on August 2, 2012 at 8:01am

Well, I can't fly it without the APM as it's flybarless, and I don't have any controller.  I'm going to set something up for a manual passthrough on flybars however.  Should be easy.

Blades were well tracked, I had some really nice Ti turnbuckles on it.  Of course one of those was thrown into an parallel universe in the crash. :(  Blades were decent quality CF blades, but I didn't look for twist.  Main shaft, etc, etc was all straight.

Simple fact is, if the APM can't fly with a heli in the condition it was in, then it's just not going to work at all.

Thanks for the offer of the heli, but I can't accept it.  It'll actually cost us both a frightening amount just to have you send it to me, and I'll just crash it eventually and feel bad.  I prefer to crash my own stuff. 

Maybe I should just get a flybarred 450 kit, then I will be able to fly it without the APM, or in passthrough.

• ▶ Reply

Permalink Reply by malcolm churn on August 2, 2012 at 8:12am

Ok Robert was just thinking it might be an idea.

How tight have you got your blades, they should be tight enough just to hold the blade horizontal when you have the heli on its side. Are they flybarless as they are weighted differently.

One last thing headspeed and dampers, you will need a harder set of dampers. and run the headspeed high. 

But to be fair if the heli sits on the ground with the head at flight speed and you cant see any Vibes, then it may be the code!?

• ▶ Reply

DeveloperPermalink Reply by R_Lefebvre on August 2, 2012 at 8:22am

Well, the dampers were whatever the kit came with so...

Blades were not FBL specific, hard to actually find those in a 450, and IMO, should be unnecessary.

Again, I come back to, if the APM can't fly the heli in that condition, it's just not "robust" enough of a system to work.

• ▶ Reply

Permalink Reply by malcolm churn on August 2, 2012 at 8:25am

Ok Robert, well that sounds final to me then....... well i'll keep plugging away :)

• ▶ Reply

Permalink Reply by malcolm churn on August 2, 2012 at 10:42am

I dont really know whats going wrong here,

Quads i would have thought put out a lot more vibes than heli's.

I have seen an APM installed with just a bit of velcro before now, and it flew great. My heli's are balanced really well, So what could be the problem?

maybe the vibes are cancelled out by each motor on a quad. I know on some passenger heli's there is a system that cancels out  the imbalance. 

Maybe the quads needs a lot more sensitive system than a heli, i have run my Loiter P's down to 0.088 and it was looking pretty good, but if it gets even a small leans issue then its off like a slapped rat. 

If the code is never going to work with a heli, then maybe its time to stop working on it. For me anyway, i have put a lot of time into it and would love to see it work, but there are a few other things in the pipe work. 

Randy what do you think? I know your probably snowed under with work, but would like to get your opinion at this point.

I'll keep testing, but if all that is happening is a code change for the quads etc and the heli code is not getting any better then it looks like we have hit a brick wall....

DeveloperPermalink Reply by R_Lefebvre on August 2, 2012 at 10:50am

Yeah, I don't get it either. 

I built the quad, and it's worked from day 1.  Never even a hint of a problem, and I haven't even bothered to balance the props!  All I did was use the blue vibration damping grommets, the same ones I originally used on the 450.  Maybe I should try them again, but I just don't know anymore.  I mean, it did eventually get the leans and crash on the 450 with those blue dampers, and it was only because a bearing or two were going bad.

We just can't have autonomous helis if all it takes is a bearing going bad (virtually undetectable unless you're REALLY thorough EVERY flight).

At this point I'm sort of pinning my hopes on the PX4 system with the Kalman Filter.  It works for rocket ships and they are the only thing on earth that shake worse than helis! ;)

What is your status.  Have you flown the past few days, and it's still wandering all over the place?  Which code are you running?

Maybe you should go back and try 2.049, or even just 2.6.  There was a big change to DCM in 2.7, and I'm wondering if it's just not working for helis, but I don't have anything to test with.

Permalink Reply by malcolm churn on August 2, 2012 at 11:12am

To be honest with you Robert, if i go back to 2.0.49 or what ever it was, and it kinda works then i'm back to square one. Also this is never going to work with a Gasser, if it cant handle the vibes from a balanced electric then how the hell is it going to cope with a single cylinder engine. Also the gasser is worth a fortune, so i'm not willing to install it !

My Futaba CGY 750 works fine that copes with ease and the vibe damping is around 0.5mm of the hardest foam i have ever seen. 

This is not really getting us anywhere.

If we are going to carry on with this then we need a path..... Forget all the other stuff and concentrate on getting it to come back to level in Stab mode, like you said if that doesn't work then nothing else will. 

You understand the code way better than i do, is there any way you can see if 2.0.49 is different to the latest?

Would be good to see if we could get a small team together with different skills.....

Do you want to be a team leader?

• ▶ Reply

DeveloperPermalink Reply by R_Lefebvre on August 2, 2012 at 11:25am

I flew the APM on an 80" Piper Cub with a Saito .56 which thumps like hell, and not the slightest problem.  I had mounted it with my rubber mounts.  Even on tickover with the APM shaking on the mounts, the HUD didn't move that much. I don't think engine vibes hurt it much, I think it's everything else going on in a heli.

Getting it to come back to level is 100% a DCM problem.  It's nothing but that.  All the stabilization and CCPM stuff on top has nothing to do with it.  If the DCM is being thrown off (and it is) then there is no hope.  And understanding the DCM is way beyond my ability.  I just know it's changed about 3-4 times since October.

What I really need to do is an A-B-A comparison.  I really want to take a step back to try 2.6 vs. 2.7, see if that is the problem.  Because I flew 2.6 on my 600, and it mostly worked.  Well, it worked for a while, and then it didn't...

I think I am the team leader already. ;)  Randy is busy on other stuff.  I think Wesley gave up, so it's just you and me now.

Which code are you trying to fly right now, is it 2.6, or 2.7?

• ▶ Reply

Permalink Reply by malcolm churn on August 2, 2012 at 11:34am

The last code i loaded and flew was 2.6 and it kinda worked but no where near as good as 2.0.49....

So which code do you want me to fly, seeing as where are 2 man team... :)

• ▶ Reply

Permalink Reply by Christoph on August 2, 2012 at 12:27pm

Robert, Malcolm. I am still there as well. In the background. But I i've to admit that i'm kind of waiting because I lost so much time because of updates which were only drawbacks. Latest code I flew was 2.3
And as I said before I never had issues with vibes although having lots of vibes on my 450. Forget about all the mounting stuff and dampening. Same with the mag and GPS. I wrote about my setup. GPS under the blades etc. all the stuff you should not do. But it works.only the routines for loiter are not elaborated enough I guess.otherwise I would have been able to post a nice loiter video.

• ▶ Reply

Permalink Reply by Christoph on August 2, 2012 at 12:30pm

And I have to agree with Malcolm. 249 or even older versions were good in some respects. In 2.3I had the feeling that tuning pids had no effect at all.

• ▶ Reply

Permalink Reply by Wesley Chuen on August 2, 2012 at 12:40pm

I repaired my FBL 450 and loaded V2.7.1 for the last local meetup.  It flew horribly.  I didn't even dare to try any Alt Hold or anything else.  That's why the thought of off loading the stabilization to another FBL controller and having the APM just to do the autonomous part came to mind.  It is similar to you put APM on a flybarred heli and with an external gyro for the tail. It works much better, right?

• ▶ Reply

• ‹ Previous
• 1
• …
• 138
• 139
• 140
• 141
• 142
• …
• 161
• Next ›
• Page