It’s time to start to think about INAV 2.1 – DSHOT and braking mode

It's time to start thinking about INAV 2.1. No, I will not give you any timeline, but I can point two features that are very likely to go into the upcoming INAV release.

The first one is Braking Mode for multirotors. I already made a video about it, so you might want to watch it first. Right now there is an open test phase for this feature made as part of my fork of INAV. If you want to test Braking Mode, please visit this page and download the hex file for your board.

On top of that, it's very probable that DSHOT will finally make it to INAV too! DigitalEntity started to tackle with the DSHOT implementation so yes, this is finally happening for INAV!

DIY 4S battery pack from 18650 Li-Ion for RC FPV drone

've made me an endurance Li-Ion battery pack for my 7 inch endurance quadcopter. With good quality Sony 18650 VTC6 it is possible to get 20A constant current which is enough for an airplane or endurance quadcopter. Works just fine and with reasoable speed of 40-50 km/h I'm getting more than 15 minutes of real flight. Not hover. Flight. And at the end, it still has some juice inside. Not bad, not bad at all.

When Red Cat tries to buy my Blackbox logs, it smells fishy

Out of nowhere a company, RedCat, jumps with a super duper web page that allows you to analyze your blackbox log with something that apparently is based on Blackbox Explorer and Plasmatree PID Analyzer, puts blockchain, artificial intelligence, law regulations into the mix and on top of that, almost offers to pay you for that. I say what?? This just does not adds up. RISC-V, blockchains, commercial drones…. too much in one product…

7 inch quadcopters fly like shit? Well, kind of, yes…

So, you got yourself a 7-inch quadcopter drone, you try to tune it, and you finally discovered that something is bloody wrong? Whatever you do, no matter how long you tune the PID gains and filtering, you can not get rid of jello and some strange vibrations? Welcome to the club mate!

Apparently, scaling 5-inch frames to 7-inch ones in XY axes does not work! Longer arms equal lower modal frequencies. Bigger propellers equal lower vibration frequency. After combining both factors, we have frame oscillations that are happening on the hardware level. No way you can tune that thing out. To make thing worse, 2205 and 2206 (even 2207) motors does not have enough torque to quickly change 7-inch propeller rotation speed.

For the details, watch the video.

This is why YOU SHOULD use only 8 channels in Betaflight!

When two weeks ago I said that you should only 8 channels when using FrSky SBUS I meant it and you just had to take my word for it. Today a small proof how Betaflight 3.5 feedforward component looks on the Blackbox with 16 channels and 8 channels. Of course, in both cases, RC smoothing type FILTERING was chosen.

INAV Airmode and Motor Stop on Multirotors and Fixed Wings

What are Motor Stop and Airmode features in INAV and how they differ from each other when used on multirotors and fixed-wing airplnes? Should you use Motor Stop on multirotor? Should you use Airmode on a fixed wing? Long story short:

  • On multirotors, Motor Stop not recommended to use while Airmode is recommended to use. More than that, you can not use them both at the same time, since they exclude each other!
  • On fixed wing aircrafts Motor Stop and Airmode are highly advised to use together.

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!