I need help on the wifi. Pixracer setup (via USB) with PX4 and QGrouncontrol, ESP-01 8266 board in correctly and giving a solid red LED, howeverâŠthere is no way I can view the network âpixracerâ on anything. Obviously no connection to groundcontrol, but I would have thought at least I would see a transmitting on something,anythingâŠPC, Samsung S4 mini etcâŠnothing. Am I missing something like having to enable the wifi transmit via a setting. Or because itâs not tramsmitting, itâs a dud?
Iâve never encountered a problem with seeing the Pixracer network on wifi, so this problem is new to me. Swapping the ESP8266 would be the simplest way to check if itâs bad.
I flew my waterproof Pixracer quad: https://goo.gl/photos/LUvZvxn18XnsEVcb7 off water yesterday for the first time. With a lake below to reduce the risk of crash damage, I tried full acro mode rolls and flips for the first time, and am pleased to say that it feels great, even with the 450 size quad. Never came close to crashing, just over-rotated a few times when using high angular rates. Some pictures coming soon, I hope.
Update: Firmware version was PX4 beta (from 2016-05-20). Except for a problem with GPS altitude accuracy, (which was a hardware, not software issue) all flight modes tested good, including RTL, which returned to the point at which the vehicle was armed (or where it took off, since both locations were the same).
Waterproof frame: http://www.aquacopters.com/store/p2/Project_X-Frame_Only.html
The frame is made of Kydex plastic: âKydexâa combination of acrylic and PVC plasticsâwas developed in 1965 purely for the intent of making aircraft interior parts. Kydex is highly flame retardant⊠Kydex has different finished textures and comes in colors⊠Itâs also expensiveâŠâ (from AvWeb).
Iâll get another and check it out, cheers.
d thought these were already flashed. Iâll get the necessary bitsâŠthanks!
Who did you buy it from? What country are you located?
AUAV. Iâm based in the UK (Scotland). Iâll give flashing it a go, see if itâll start transmitting some radio
@vladM My âaquaâ quad can carry two 3S or 4S 2200mah LiPo batteries. So far, Iâve been flying on a single 3S/2200 and all-up flying weight is only 960g. Motors are Emax MT2212 900kV with 10x4.5" props. Hover current is about 9A and full throttle current is 32A. ESCs are ZTW Spider Pro 20A with BlHeli firmware. The ESCs are advertised as one-shot capable, but Iâve had no luck with that so far.
Hi,
I have my PixRacer installed on 450 quad. I have done all the calibrations and everything seems working on the bench without propellers. I wonder what is the right way to do PID tuning with PX4. I know how to do it with APM, but it seems like PX4 is different. This guide require to hold it in the hand and I am not sure if it is safe to do with the large quad.
https://pixhawk.org/users/multirotor_pid_tuning
Is there any other way?
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Iâm looking at putting the pixracer in a flying wing. With the extra servo ports will I be able to trigger a camera on those channels?
Iâm wondering the same a vladM. I have a large 680mm frame with 15x5.5 props - I definitely do NOT want to hold that in my hands while tuning.
I did the In-Hand tuning with a Tarot 680 Hexa with 13x5.5 and a F450 with 9.4x4.3⊠It is possible, but a good idea to assign a Kill-Switch. Oscillations will occur but usually vanish immediately when you lower Throttle. Check that your cabling and Motor direction/Props Mounting is ok.
Anyway normaly the Copters should fly with default Values. You can assign an RC Channel to tune Parameters. IMHO the Handling is not yet perfect or self explaining but it basically works.
I am thinking about this setup, it is not optimal but it should be ok for a beginning. Advising to hold new and probably unstable system in the handâŠ
@vlad @thedevleon If Iâm not sure whether a large quad will be stable, I strap it down (loosely) for the initial tests. Once Iâm sure it wonât flip at hover throttle (reducing the gains if necessary), I proceed to a free hover and fine tune the PID gains. Itâs been a long time since I used a test stand as in the video, I find itâs not necessary given the reliability of the PX4 firmware.
Thanks, I had my first test flight on Sunday, out on the open field. It was windy with rain and some gusts. Everything went well. I had just one battery and did not have a chance to do any PID tuning. It was behaving well with the defaults. Tried stabilize, althold, positionhold and RTL. Sometimes positionhold and yaw would make it move around couple of meters, but It may be the wind.
One thing I noticed, that I canât disarm it in positionhold or althold after landing. Also realized that the kill switch does not disarm motors 
After the flight, I tried to load logs in the Mission planner and it worked after renaming px4 to bin, but automatic log analyze did not work and the time stamp was not populated properly. What do you use to analyze logs with PX4? I am interesting to see if my compasses do not have interference and vibrations as well. Also it would be interesting to understand wondering in positionhold.
Glad to hear your 450 is flying now. Congratulations.
In POSCTL, the quad will wander around following the GPS solution. If EPH is 1 meter, you should expect to see a ârandom walkâ with an RMS radius of 1m.
I think there has been a recent change to allow arm/disarm in additional modes, but Iâm not sure if thatâs documented yet.
The kill switch intentionally does not disarm, in case it were accidentally operated in flight, but maybe that should change. At the very least, it should be clearly documented somewhere.
PX4 logs can be analyzed by uploading to the âlogmuncherâ: http://logs.uaventure.com/ or by running FlightPlot: https://pixhawk.org/dev/flightplot
The logmuncher generates accelerometer plots and thrust/mag plots to aid in vibration and magnetometer analysis.
I thought I would share my PID gains for a small 150-class quadcopter (albeit rather heavy for its size).
Frame: Diatone Lizard 150
Motors: DYS 1104 with 3020 props
Battery: 3S
Total weight: 270 grams
Thrust/Weight ratio: approx. 1.6
Tested in manual mode and position control mode. Iâm not an experienced pilot, but for what its worth, it was flying pretty good.
The critical part turned out to be increasing time constants. With 0.15s there were lots of oscillations, and I had to decrease P gains to as low as 0.02, but then the quad was too sluggish and barely flyable. After increasing TC to 0.25s I was able to increase the gains.
MC_PITCHRATE_P 0.05
MC_PITCHRATE_I 0.02
MC_PITCHRATE_D 0.001
MC_PITCH_P 7.0
MC_PITCH_TC 0.25
MC_ROLLRATE_P 0.04
MC_ROLLRATE_I 0.02
MC_ROLLRATE_D 0.001
MC_ROLL_P 7.0
MC_ROLL_TC 0.25
Btw, it looks like there is a mistake in the docs.
D Gain Tuning (âŠ) Typical value is around 0.01âŠ0.02.
I didnât see such high values in any of the presets, arenât typical values more in range 0.001 to 0.003?
Hi All,
I recently started using PixRacer and working on building my tricopter. I have some questions about firmware, getting tilt servo working etc. Is there any thread I can refer to, which is has some discussions about PixRacer for TriCopter ? I can read through it first before asking any questions.
Thanks,
Anand
Hi, Iâm converting a small old quad from a KK board to pixracer.
Which fw is most stable to use with pixracer? I flashed px4 beta through qgc but have some problems. When I connect qgc via USB cable and no batteri the pixracer boots up already armed so I canât configure flight modes etc. I canât disarm with the radio but when I disarm through qgc I constantly get warning messages that I have to low voltage. I have USB 3 connectors on the laptop.
If I power up the board with a battery arming seems ok. However if I spin up the motors in stabilized they behave a bit strange, one or two motors sometimes slow down and stop completely and I canât make them turn again without rebooting. However I have verified that the motors are connected correctly, they spin in the right direction and they respond correctly to tilting and pitching etc.
Thanks!