Matek F722-STD not booting without battery and how to fix it

What to do when Matek F722-STD flight controller is not booting without connected battery and connection from Configurator is not working? Simple, power GPS and magnetometer from a different pad.

All 5V pads are powered only when external power is supplied to the flight controller. Not when power is applied via USB cable. If you connected GPS and magnetometer to 5V pad, it will not work and screw I2C bus up. To solve this problem, connect GPS to 4V5 pad instead!

qUark Vision F4: flight controllers designed for INAV

Things are changing in INAV world. Different manufacturers start to realize that world does not end on racing miniquads and people might be interested in other types of flight controllers. Flight controllers that were not designed with racing in mind. And today I can finally show you prototype of such flight controller: qUark F4 Vision

qUark F4 Vision Flight Controller for INAV

qUark F4 Vision Flight Controller for INAV

What is so special about qUark F4 Vision. To be honest, not that much. Setup looks pretty standard:

  • STM32F4 CPU
  • MPU6000 IMU (gyroscope and accelerometer)
  • built-in OSD
  • built-in barometer
  • 8 PWM outputs
  • S.Bus inverter
  • Buzzer port
  • pins for WS2812b RGB LEDs

qUark F4 Vision Flight Controller for INAV

Until now, nothing fancy, right? Good stuff begins when we take a look at details:

  • PMW outputs power rail is separated from the onboard 5V line. That means you can use high voltage servos, as well as do not worry about frying onboard 5V voltage regulator
  • There is no onboard 5V voltage stabilizer. 5V has to provided from external source of your choice
  • It is not 36x36mm with 30.5mm hole spacing. It's still 30.5mm hole spacing, but one side is longer to fit all PWM outputs
  • Bottom side of PCB is flat. There are no electronic components over there. And that means FC can be attached with double-sided adhesive tape. Great for foamies
  • There are 3 fully operational UARTs (1,2 with S.Bus inverter and 4), separate I2C port (not shared with any UART like on all Revo derivatives) and possibility to use Software Serial
  • Special work in progress UIB port that is specific to INAV. It does not do much now, but it might change in the future
  • dedicated pads for HC-SR04/US-100 sonar rangefinder (I have not seen that for a while)

Something different, right? I'm putting mine on my experimental flying wing where it will feel like at home.

qUark F4 Vision Flight Controller for INAV

Like I wrote at the beginning, this is a prototype. It can not be bought yet. But if you are interested, you might email Malcolm at [email protected]

The most popular flight controller for INAV – Q4 2017

It's been a few month since, for the last time, I presented to you the most popular flight controllers used together with INAV firmware. So, as you can suspect, it is time for the next one. This time, I've looked into last 3 months of the year 2017: October, November, and December.

Important, this is not the number of boards flashed with INAV, but rather the number of times a board was connected to Configurator!
This counts TARGET software name, not retail name. For example, all clones of Naze32 will be counted as Naze32

Board name Q4 Share [%] Gain/Loss comparing to Q3 [pp]
SP Racing F3 22 -4
Omnibus F4 Pro 18 +3
Naze32 15 -5
Omnibus F3 11 -1
Omnibus F4 v3 8 +5
Omnibus F4 v1 4,5 +0,5
Matek F405 4 +3,5
SP Racing Evo 3 -0,5
CC3D 3 -0,5
Revolution 1 -0,5

Remaining 10% of market share is distributed among other targets.

As you can see, Omnibus F4 series dominates. All revisions of this board have 30,5% share when combined. Also, all F3 and F1 based flight controllers are giving ground to much more powerful STM32F4. To compare, in August 2017, all F4 boards had 25% when combined. Right now they have 39% market share when combined. And this is good!

CPU Family (TOP 10 only) Q4 Share [%] Gain/Loss comparing to Q3 [pp]
STM32F1 20 -6
STM32F3 40 -6
STM32F4 40 +12

Another good news is that share of OSD equipped flight controllers is also growing. In August 2017, 47% of boards were equipped with OSD. Now it is 50,5%.

Hands on: FrSky XSRF3O flight controller

Since I just started to add support for "old" FrSky XSRF3O flight controller to INAV (expect this in a release after 1.8) it might be a good idea to share few words about it.

FrSky XSRF3O flight controller in a box

First of all, it comes in a box. Why am I mentioning this? Because none of my flight controllers, and I own at least more than a dozen, came in box. C'mon, this is huge! I'm not joking, this is really a nice touch.

Continue reading Hands on: FrSky XSRF3O flight controller

And the most popular flight controller for INAV is… (August 2017 edition)

More than 2 months after previous “What it the most popular flight controller for INAV“, welcome to second edition.

I mportant, this is not the number of boards flashed with INAV, but rather number of times a board was connected to Configurator!

This counts TARGET software name, not retail name. For example, all clones of Naze32 will be counted as Naze32

Data was taken in August 2017, multiple connections during single user session are stored as single entry.

  1. SP Racing F3 – 25% of all boards, lost 4 percent points
  2. Omnibus F4 Pro (aka v2 aka SD) – 15% of all boards, gained 5 percent points
  3. Naze32 rev. 5 and 6 – 13% of all boards, lost 6 percent points
  4. Omnibus F3 – 12%, lost 1 percent point
  5. Naze32 older than rev. 5 – 7%, gained 2 percent points
  6. Omnibus F4 v1 – 4%, gained 1 pp.
  7. Omnibus F4 v3 and v4 – 3%, first time in TOP 10
  8. SP Racing F3 EVO – 3%, lost 2 pp.
  9. CC3D – 3%, lost 1 pp.
  10. AnyFC F7 – 1%, first time in TOP 10

Other targets have 14% in total.

This data also says something about CPU generations distribution:

  1. STM32 F1 – 27%
  2. STM32 F3 – 47%
  3. STM32 F4 – 25%
  4. STM32 F7 – 1%

What changed comparing to June?

  1. First F7 board appeared in TOP 10!
  2. F1 and F3 targets are loosing market share, while F4 and F7 are more and more popular
  3. Naze32 is no longer second most popular board
  4. OpenPilot Revolution and Airbot F4 (more less the same) are out of the TOP 10
  5. Boards with integrated OSD are more and more popular. They already have 47% of market share

Very custom FPV quadcopter for my daughter

When few months ago my older daughter (10 years old) started to express interest in FPV quadcopters, I was both happy and concerned. Happy, since I would have someone to fly with. Concerned, since she has no idea how to fly, I do not have a quadcopter for her and there is a big chance she will get bored fast. So, instead of getting her a brand new, cheap, standard off-the-shelf drone, I checked my repository of “spare” parts and drones, purchased this and that and week later “Omlette du fromage” came to life…

Scarab Knife 200 cartoon sticker bomb

Continue reading Very custom FPV quadcopter for my daughter

Flight Controller Soft Mount – is it worth it?

Is it worth to soft mount flight controller? Are gyro pads I recommended here better than rubber standoffs? I feel that they are better, but I do not have any solid data to prove it. So I can only tell, that I find them better and that is all. But, I can answer the question is it worth to soft mount flight controller at all. The answer is YES and here is a proof…

The problem of twitching motors

After I updated my 5" racer to stronger motors (EMAX RS2205S 2300KV over RS2205 2300KV) I noticed something very very irritating: twitching motors. When the throttle was in more less middle position or after rapid throttle change, twitching from motors was very audible. Quad was flyable, but performance was very low. I had to reduce yaw P gain by more than 50% not to see those twitches in FPV footage!

Blackbox log revealed the truth: from time to time, the strong vibration was getting into yaw gyro traces. I also localized the source of those twitches: stronger motors with more torque and higher radial acceleration were able to shake the whole machine when the frequency was close to the resonance frequency of the frame.

hard mount twitch example

Continue reading Flight Controller Soft Mount – is it worth it?

And the most popular flight controller for INAV is…

Did you ever wondered what is the most popular flight controller? Hardware I mean. I can tell you πŸ™‚ OK, maybe it will not be a full truth, since I have data only from INAV, but assuming that distribution for Betaflight and Cleanflight is similar, we might know what is happening…

Important, this is not the number of boards flashed with INAV, but rather number of times a board was connected to Configurator!

This counts TARGET software name, not retail name. For example, all clones of Naze32 will be counted as Naze32

Data was taken in June 2017, multiple connections during single user session are stored as single entry. Continue reading And the most popular flight controller for INAV is…