Best alternative to Naza? Arducopter?

[R_Lefebvre]

Rob, if I was back home in the UK I would be tempted to try your frame but out here with limited tools and spares its a no-go. Just seeing your bent motor mounts would mean an expensive UPS and Duty tax - plus a few weeks wait wondering if the replacement parts would ever arrive!

So I'm fairly comfortable with the F550 and APM. How do you compare it's stability against the Naza+GPS?

I cannot fairly compare the stability, as I have not flown the DJI products. I'd like to pretend I could make a comparison with something I haven't actually used thoroughly, as so many do, but I won't. All I can say is that with the latest code, the stabilization is as perfect as I could imagine it could be. It is stable, steady and smooth in a hover, and also responds perfectly to quite dynamic manoevers. It does a GPS hold within about a 1-2m box, and flies waypoints really well. It's just working very very well lately. Before June it was honestly not great, but since June it's been pretty solid, and the 2.8 release made the dynamics very good.

 

[Paul881]

I cannot fairly compare the stability, as I have not flown the DJI products. I'd like to pretend I could make a comparison with something I haven't actually used thoroughly, as so many do, but I won't. All I can say is that with the latest code, the stabilization is as perfect as I could imagine it could be. It is stable, steady and smooth in a hover, and also responds perfectly to quite dynamic manoevers. It does a GPS hold within about a 1-2m box, and flies waypoints really well. It's just working very very well lately. Before June it was honestly not great, but since June it's been pretty solid, and the 2.8 release made the dynamics very good.

Rob, I appreciate your honesty rather than pretending.
Knowing what you know, do you expect further improvements with the firmware and updates for the APM?

 

[kloner]

when people first get into anything new they hit a learning curve. I have friends that say they like messing with settings and tuning and there the most misserable and far behind learning what you can when the unit just flies. They sit there and hover....... 6 months later. I'm 6 months into fpv flying,,,,,,, first time was Easter. if i had been sitting there messing with codes watching it flip over, theres no way i'd be where i am now..... Probably would have lost interest. Good luck

 

[R_Lefebvre]

Rob, I appreciate your honesty rather than pretending.
Knowing what you know, do you expect further improvements with the firmware and updates for the APM?

Yes, there are a few things still to come. We are working on inertial position hold as well as alt hold. We're also working on some more changes to improve reliability. This is mostly failsafe and error detection, not stuff like "it won't do FOD" because it's already pretty good in that respect. This is stuff like... recently a guy had a fly-away because he strapped a cell-phone to his quad to use the camera, and left the phone transmitter active. Looking at the logs, we can only conclude that the EMF being radiated from the phone transmitting blasted the PPMEncoder chip, making it lock up. So now the main process will look for a PPM lockup, and then go into failsafe mode. That's just to demonstrate the level of detail we are taking this to.

We're basically going to be tweaking a few things, but we have seriously pushed the Atmel chip as far as it can go. The clock-cycles are well managed and it executes pretty reliably. It's taken a lot of serious software engineering to get this far with it. Looking at the quad-parallax-propeller chips in the Hoverfly makes me wonder what in the heck they are doing with 40 times more processing power than us. Another guy likened it to "two guys playing catch in an empty pro stadium" :cold:. But we are simply running out of RAM. So there won't be a lot of new whiz-bang stuff in the future for APM2. Just bug fixes and improvements to existing functions.

I still have some work to do on the SRH stuff, but that's not too relevant here. I may have to remove gimbal and geo-fencing support from the TradHelis due to the RAM limitation. I'm also trying to increase the maximum waypoint speed. Currently the auto code starts to perform poorly above 36 km/h, I'd like to be able to do 70. Stuff like that.

 

[Paul881]

Rob, Kloner, thanks four your replies. I really need to think long and hard at what I want to do at this stage. Kloner is probably right; just get out there and fly. Otoh, I like the idea of messing with stuff- I am someone for whom the journey is more interesting than the arriving. Decisions, decisions.........

Thanks again to you both.

 

[R_Lefebvre]

when people first get into anything new they hit a learning curve. I have friends that say they like messing with settings and tuning and there the most misserable and far behind learning what you can when the unit just flies. They sit there and hover....... 6 months later. I'm 6 months into fpv flying,,,,,,, first time was Easter. if i had been sitting there messing with codes watching it flip over, theres no way i'd be where i am now..... Probably would have lost interest. Good luck

Well, different people like different things. If all you want to do is just fly around, you don't have to spend more than a few battery packs getting it set up and tuned. If a few battery packs for tuning is too much effort, then, well I don't know what to say.

What I have been doing for the past year is not typical. I've learned a great deal about electronics, programming in C++, and aerodynamics. I do this because I enjoy it. I do it because I like building things. I do it because I like helping people.

But this is not required for normal users. To just get flying, you need to spend a few battery packs tuning your Rate PID's. That's it. In fact if you're happy with mediocre performance, you can be done in just a single pack.

 

[xtrmtrk]

Rob, Kloner, thanks four your replies. I really need to think long and hard at what I want to do at this stage. Kloner is probably right; just get out there and fly. Otoh, I like the idea of messing with stuff- I am someone for whom the journey is more interesting than the arriving. Decisions, decisions.........

Thanks again to you both.

Don't forget, if you hope to fly FPV there's plenty of opportunity for creativity and building there. I've spent a surprising amount of time planning and building the video and telemetry on my craft.

 

[Paul881]

Well, different people like different things. If all you want to do is just fly around, you don't have to spend more than a few battery packs getting it set up and tuned. If a few battery packs for tuning is too much effort, then, well I don't know what to say.

What I have been doing for the past year is not typical. I've learned a great deal about electronics, programming in C++, and aerodynamics. I do this because I enjoy it. I do it because I like building things. I do it because I like helping people.

But this is not required for normal users. To just get flying, you need to spend a few battery packs tuning your Rate PID's. That's it. In fact if you're happy with mediocre performance, you can be done in just a single pack.

Rob, that's impressive and whilst I'm not sure I want to go to that depth of programming, nevertheless I'm not one who doesn't take time to understand what's under the hood.
For example, I have my own music recording studio and have built my own top spec PC to enable that to be at the heart of the studio. Whereas I could have gone to a specialist builder and bought one from them but I didn't because I wanted to understand what it was I was building so I could fix it when it didn't do what I wanted it to.

Don't forget, if you hope to fly FPV there's plenty of opportunity for creativity and building there. I've spent a surprising amount of time planning and building the video and telemetry on my craft.

At this stage I am reading, looking and learning and i can already see the knowledge and planning road stretching out a long way ahead of me, so I get what you are stating here. It's part of the joy of starting a new hobby. Well, nearly new, 35 years ago I flew R/C planes.

 

[Paul881]

We're basically going to be tweaking a few things, but we have seriously pushed the Atmel chip as far as it can go. The clock-cycles are well managed and it executes pretty reliably. It's taken a lot of serious software engineering to get this far with it. Looking at the quad-parallax-propeller chips in the Hoverfly makes me wonder what in the heck they are doing with 40 times more processing power than us. Another guy likened it to "two guys playing catch in an empty pro stadium" :cold:. But we are simply running out of RAM. So there won't be a lot of new whiz-bang stuff in the future for APM2. Just bug fixes and improvements to existing functions.

Rob, limitations of RAM is a big drawback to adding future functionality. Do you see a time soon when the APM will need to be redesigned to have larger RAM memory?

 

[RTRyder]

Another alternative is the current generation of MultiWii Mega boards with the 2.1 firmware release. A sensor upgrade along with the newest firmware has tightened up the performance of these boards and the ATTI, Autolevel, and GPS position hold all work. No they aren't as locked in as a Naza but properly setup they do work as well as an MK and for a lot less $$$. These boards will also run the MegaPirate firmware which allows use of the Ardu ground station with all of its functionality, or you can have the basics with the MultiWii firmware.

I started with the MultiWii over a year ago on a Quadrino board and firmware 1.7 which worked fairly well but clearly the advanced functions needed a lot of work. The board flew fantastic in manual mode and OK in autolevel, altitude hold was still a long way from perfection. Fast forward a year and I just recommissioned the quadrino with 2.1 firmware and now it all works. The icing on the cake is it flys quite well on a DJI F450 frame using the default settings. I could tweak a bunch of things to try and make it better but that's optional at this point from what I'm seeing in the intial test flights.

I recently finished a build using one of new generation Mega boards with GPS, same deal, it flys quite well on the default settings, just needing afew tweaks on the GPS to lock it down a bit better. Last weekend I put a cheap camera on it and did three FPV flights on the quad with MultiWii Mega, wasn't quite as solid as my Naza FPV quads but one thing it did much better at was FPV in manual mode. With a Naza you can set it up to fly well in manual in which case it usually has completely wrong settings for ATTI and GPS modes, it will oscillate and wobble all over. Conversely if you set it up to be nice and smooth in ATTI and GPS it feels like it's barely controllable in manual which makes it an either or proposition. Not so with tthe MultiWii, it flys smooth and solid in manual mode and then you can turn on autolevel and various other functions using TX switches that you define in the MultiWii GUI. End result is it appears to be a good and inexpensive alternative to the Naza for FPV, even having RTH and failsafe modes that actually work. I've tested the RTH and found it to be almost as accurate as the Naza, have yet to try the failsafe.

The best part is the boards with GPS can be bought for less than the cost of just a Naza GPS unit, I paid around $140 for the MultiWii Mega with GPS, there are even less expensive units available from HK, Goodluckbuy, and even a couple US based vendors. Software is opensource and well established, though don't expect it to be as plug and play as DJI but with the GUI andthe current firmware it's not the tuning nightmare that MultiWii used to be. I think it works well enough that I may use this for all future builds for FPV and sport flying and I'm considering trying it on an APV hex, I think it can do the job.


The future of multirotor flight controllers I believe is with the open source systems, eventually the capabilities will match what the big boys are doing now at a fraction of the cost in hardware.

Ken

 

[R_Lefebvre]

Rob, limitations of RAM is a big drawback to adding future functionality. Do you see a time soon when the APM will need to be redesigned to have larger RAM memory?

Yes, absolutely. In fact it's already here. We have the PX4 system which comes with a STM32F4 processor which is much much faster and has much more ram. They're just working on getting Arducopter up and running on it now.

 

[Paul881]

Yes, absolutely. In fact it's already here. We have the PX4 system which comes with a STM32F4 processor which is much much faster and has much more ram. They're just working on getting Arducopter up and running on it now.

Is the PX4 released yet?

 

[R_Lefebvre]

Yes, but the code does not run on it yet. It's a big job to port it over because the PX4 is intended to run with an RTOS.

 

[xtrmtrk]

Does the team have a target date for their first release that will fly a quad?

 

[Tahoe Ed]

CC3D if you are not concerned about GPS or wait for the Revo. The software for the Revo is still in the Alpha version and needs a lot of work before it is ready for prime time.

 

[R_Lefebvre]

Does the team have a target date for their first release that will fly a quad?

You asking me?

The board will already fly a quad, but it's using ETH Flying Circus code from Switzerland. I don't know a lot about that. I've just seen the vids. ETH actually designed the PX4 and have 3DR manufacture it. The original intent was for it to be a board for university research groups to use, but Arducopter basically jumped onboard when we saw it.

Timing for porting Arducopter, I don't have a date.