This is a discussion to focus the feedback and support of ardupilot on the PixRacer board from AUAV.co.
We believe that all teething problems encountered are now resolved and so we recommend people load Copter-3.3.4 which is available for all multicopters through the Mission Planner's (and other GCS's) Install Firmware screens. Note that because regular Pixhawks are still on Copter-3.3.3 the install icon may show Copter-3.3.3 but rest assured, Copter-3.3.4 will be installed (you can check the version by looking at the very top of the Mission Planner).
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Strange question. Pixracer runs ardupilot fine as this thread shows it.
Not for me and many other.
e.g. In AltHld the altitude varies +/- some Meters
Within 3 mins the Hexa sinks continuesly in AldHld
After landing the Altitude shows 5m, after arming 0m.
Autotuning does not work (No reaction)
Increasing PID higher than default with MP Beta only.
In Loiter uncontrolled yaw up to one complete turn.9 Sats, hdop 0.9
My setup: Hexa DJI F550 origine 1.8 kg, Pixracer R14, AC 3.4-rc1, MP 1.3.38.1
Same frame with Pixhawk, AC 3.3 perfect hoovering and behavier.
@Hugues. I know that arducopter has not never been designed with FPV racing as an objective. But things are changing...,
- multicopter become smaller and smaller
- FPV racing is growing quickly
- some guys invest lot of time (and maybe money?) in a board nammed "pixracer"
- lots of thing can be done with a little autonomous beast :) -> can be a good plateform to pratice safely FPV racing (with geofence etc.. etc...)
- more ardupilot fans (like me) will become FPV racing pilot
Ardupilot was in advance on lot of many multicopter firmware by the past. But it was the past.
Look at the works made arround ESC firmware (multishot etc...limitation is the gyro sampling...), Boris B synced PID with maximum output supported by Esc ...On the other hand, arducopter pid calculations stays at 50 hz? Optimisations can by easy done, isn't it? Lot of work has been done in arducopter, it will be great if one arducopter objectives become : performance and efficienty on the Stab and Accro mode
Nota : FPV racing is a good way to expirement new feature because machines are often crashproof.
Just a comment, Pixracer board was not designed for FPV racers , as said by the creators themselves. Of course it can be used for it.
About the refresh rate , it has been tested scientifically and shown this is pure hype not bringing any real advantages in flight. Believe it or not. ESC efficiency has been tested using different versions of firmware including Simon, blheli, one shot, and results show: no differences whatsoever.
I was agree with your position, how can you explain the gate in fly response, (same 250 frame, oneshot125 etc...) with a little CC3D and betaflight on one hand and pixracer / arducopter on the other hand?
If we don't test IRL by flying, tuning and "smell it"...
How can we say it's not a way to make the things more efficient?
Do you have a paper on that? I'm interested.
Here on diydrones, this post is very interesting:
http://diydrones.com/forum/topics/worlds-best-esc-making-it-better
You might be better off checking the real time facts and proof posted here. This info comes from people who stretch esc's, motors and props to their absolute limits FPV racing.
www.miniquadtestbench.com Their was never any real proof posted on worlds best esc, alot of talk. Also check out http://www.rcgroups.com/forums/showthread.php?t=2492809&page=109
well, if you take time to read the results page of the MQTB its in line with what I've posted based on my experience.
the mentioned ESC is rather cheap $13, so should be relatively painless to check it out. just let me tell you, before I put them on a 7kg hexa, Ive ran them for 20min @ 50% throttle inside CF tube, after that for 3min of 100% throttle. this is at 6s spinning 1555 DJI prop on 4114 400kv motor. also, standard sync loss tests. the added resolution (number of steps between rpm) adds to stability, paired with enabled oneshot125.
Huge, don't bother since than a lot has changed, the best ESCs right now are the ones which are able to run BLHeli_S (Small_Throttle_Steps) with both sides having fast n-gates, they have the motor PWM synchronized with MCU master clock, so motor PWM timing is hardware controlled. this results in highly efficient operation not to mention perfect motor timing and very smooth throttle curve. Really, I can't hear the motors running, only the mechanical friction and absolutely no sound from the winding/magnets. Also, regarding the original Forest's post, for the most optimal ESC-motor config one must do proper configuration with blheli/simonk (many times need to compile code yourself), of course good hardware is essential, but even HK multistar motor's performance can be noticeably improved by properly tuning ESC.
p.s. I suggest you take a look at 30A RACERBEE PRO ESC by FVT, fets are 100A rated, both sides are fast N channels (not a compromise fast high and slow low as most are), SilabsF396MCU, 30A continuous with ZERO airflow, 2-6s.
so far its the best preforming ESC I came across, though if installing in something larger than 300 frame size I suggest putting a CAP on its input, though manufacturer says it's not necessary, but I did it anyways.
Is onshit125 a step up from oneshot125? (see prev. post, last line).
In all seriousness though you are suggesting that even for bigger machines (non racers) we should be going this direction. Do you think Spyder 40A Optos are worth acquiring as I need to 40A ESCs for a Y6 that will be carrying a Nex class camera. I have Afros flashed to BL Heli but you think I will notice the difference by getting Oneshot125 capable ESCs?