Hi all! After some pid tuning, but require further adjustment, today i made the first real flight with my "heavy ArduXOcto", i open this thread for sharing my experience if someone else wants build a similar "heavy configuration" using ArduPiloltMega 2560, IMU, GPS and Baro, etc.
I have previously tested more expensive systems like Mikrokopter and Wookong, and unfortunately i think there is still much hard work over the code for make this electronic flight like the competition, but considering the price i would say that goes too well.
I'm still quite satisfied, even though my copter in some aggressive maneuvers tend to wobble a lot, and in the Loiter mode some circles is inevitable because I believe that the management of the accelerometers correction is not optimized or inactive.
Over the baro range i've a good altitude precision, max 20/30 cm of excursion.
This is my hardware configuration:
- APM 2560
- OilPAN IMU
- Mediatek MT3329 GPS V1.6
- XL-MaxSonar MB1200 (with active filter and "thermal mods", 4 x 10 ohm resistor around the case)
- ESC HiModel Pro 30A, in high timing mode
- Two switching BEC 6V 5A (connected to electronics through two diodes 3A, the tension output is 5.33V)
- Motor TigerMotors MT2814 710 kv (mounted with 3° inclination for increase YAV control)
- Props APC 13x6.5 "E" (X8)
- Two-Way telemetry "Mikrokopter Wi232" (890 MHz)
- Six led strip connected to APM (pins AN8<->AN13 through ULN2003), thanks to u4eake for the code
- Homebuilt frame, mixed aluminum / vetronite (by AleBS, thanks dude! :P) + homebuilt hood
- Lipo 4s2p 5000 mhA 40c
- TX Futaba T12FG
- RX Futaba R6008HS
I'm uploading the video on my youtube channel, post them soon, for now I leave you some pictures.
I enclose the parameters used for the flight test in a soft wind, but there's one error, the real "Rate Pitch I" is set to "0".
Yeah, but i've some flutter vibration of the props when descending too hard, now drive motors directly over the arms with two screws like Mikrokopter, just for remove the motor mount, it's too week.
I also get flutter when I descend too fast with my arducopter quad. Is there a solution to this?
Flutter of the props or the arms?
Check this, is must important because the flutter can tilt the sensor of OilPAN, then crash your copter.
When you hear the flutter sound immediatly go throttle down, then go up slowly.
If you try to recover the copter with more throttle the flutter increase and and crazy electronics.
See my video with broken props, when i hear this sound going down with throttle, then i recover my octo at fev meters to the ground.
The whole copter wobbles if I descend too fast. Im uploading an FPV video of it.
My connection is slow, will post when its finished.
Hi Marco, I follow your thread with great interest. I am planning to aquire an octa for aerial photo and video.
For now I am working with a Maxi Joker 2 and a PhotoShip One 360 3X camera mount, but I am eager to step into the multirotor world. For the moment I am experimenting with a 3DR kit, but this is paused waiting for better driveline parts.
Anyhow, your homebuilt frame looks very good! Professional finish.
But I could read somewhere that you are using Droidworx frame and Photohigher mount for your professional jobs, and thats just what I am considering to buy and to top up with the new generation APM hardware.
May I PM you about your experiences with DW and PH?
Regards / Tomas
Hi Tomas, thanks for compliments!
Yes, for my work i use a Okto Droidwork with pro cam mount, Pulso Motor, Mikrokopter electronics.
I consider MK at the moment the only system capable of sustaining acceptable reliability.
To make you understand has happened to me several times to land and to realize that a propeller had broken in half (without a paddle), because there's two way communication with the fly electronics and the esc, and if an in-flight engine works differently than other the throttle for this one going down automatically, and you can fly without problems, with good stability without one motor.
With APM is impossible, one broken prop and the drone going down for the high vibration.
On my video "boken prop" i'm lucky because one of the plugs of the engine vibrated came off because of the high vibration, and this has fortunately turned off the engine and save my drone.
Concluding: for your business i definitely recommend Droidwork frame & cam mount, with all MK electronics.
Yeah, I watched that broken prop video. I did not realize broken props would be such a (common) killer :-/
Reliability is paramount for serious AP work and now I feel slightly discouraged realizing that a crucial feature is still missing in the AC realm. MK is proven but I was hoping to stay out of there due to pricing and policies (about commercial use and waypoint range limits). Besides that I love the open source idea.
Let´s lobby for the introduction of bi-directional ESC-APM communication in the AC realm. From safety / reliability perspective everybody would benefit from this!
Maybe this initiative is the first step into that road...?
MK is only a big toys ... and is a closed source project ... and a lot of people broke their propeller also with MK. The i2c esc is not so good have a lot of problem ... i2c is not a good interfare is not safe as pwm ... if you lost the bus lost all the esc :( That's not happen with pwm.
Then is possible to set also standard ESC with same control that go down the power if there are some problem on motor ... MK i2c ESC don't check the vibration on motor .. only temperature and then cut off the power.
Today Emile found a bug that could influence the loiter and navigation functionality. So we are very near to MK quality of flight in stable and automatic functionality. The advantages is that all code is opensource.
Emile and Me are working on Arducopter32 that use MP32 instead of APM . We have a lot of more power.
The MP32 yet support CAN bus and I2C esc. I yet doing a lot of flight with MK esc and VR ESC.
But the advantages of PWM esc is that you can choose also 150 Amp ESC for your project without any kind of limit With Mk is not possible.
This is the link to our i2c ESC ... http://www.virtualrobotix.com/page/vr-bl-controller-10 now is not yet supported product because is more expensive :( and haven't so advantages respect of standard pwm available on the market.
In the next week i hope to found time for doing some video no AC32 2.0.56 , is yet available on multipilot32 the repo with last update also the Emile Patch.
You are doing a great work with your okto . Your work is great and professional ...
That's ESC is very good is based on STM32F1 the same micro that i'm using on MP32 . We have a lot of power with that micro . At the moment that project is closed source and the board don't support i2c or can bus. I spoke with Timecopt about that ESC one week ago. I hope that in future revision became opensource and support new bus for interface it with our great project.
I saw also the Rock esc project they told in their presentation that the project is opensource and support can bus and i2c .... I'm waiting the evolution of that project very interesting for us.
I am following with interest the discussion about this esc.
Regarding the restricted policy of MK i agree with you, but with this one the "loiter", "stable" and "rtl" is really another world, of course there's much more expensive sensors mounted on their systems but the difference is really tangible.
See my video, with a little Octo (not XL), it's not stabilized with software:
If today i were to fly with Epic on board (40,000 $ pro cam) i would feel safer 30% with ArduCopter, 90% with MK, but it's only my opinion.
I talk about my personal experience, when something happened with MK has always been my fault (lipo not charged, etc.), and i've over 600 flights assets with two different configuration.
And that is clear, i also hate the restrictive policy of MK! :-)
I think we all prefer the open source spirit rather than proprietary projects as MK. And we all hoping so much that ArduCopter family will catch up on performance and reliabilty to be on par with MK (and DJI?).
But when Marco says that his personal experience is that MK have the lead today, I believe him. He does not get payed to say so. The concept of main unit getting status info from ESC is simply a prerequisite for error handling / redundancy. If the solution (e.g. I2C bus) brings an own voulnerability then one might consider (referring to statistics) which failure is the most likely, I2C bus failure or propeller breakage. I get the impression that the prop failure is the bad guy...
But Roberto, your AC32 initiative is brilliant. I salute all efforts made to push the evolution harder :)
Especially within the open source realm!
When you watch at the Arducopter project and derivatives, specially since one year, it seems to me that its development is faster than every other commercial project. We have now an almost complete system, low cost, and performance is very good.
Reliability is not a concern for me on the Arducopter side. I flew an expensive high load frame, sometimes agressively at more than 20 m/s, during 7 hours without any crash. And i was a beginner multicopter pilot at the beginning.
If you choose high quality motors, batteries, ESC, BEC, and if your frame is correctly assembled then reliability will be very high and you'll be able to use it even for professional jobs.
But perhaps that the most interesting in this project is the opening, the community power, and the evolution rate.
Restiling: i've removed the vetronite motor support because there's a lot of vibration with this, motor is now mounted over the arms like Mikrokopter.
Stay tuned for the next video... :P