Author: Paweł

  • Connecting ultrasonic rangefinder (Sonar) to INAV

    Keeping constant altitude with a drone is not a trivial task. Specially, if drone is supposed to keep give altitude very precisely few meters above the ground. One of the reasons for it is difficulty of reading precise altitude. Barometer can drift when atmospheric pressure changes and can produce a lot of noise. GPS is…

  • WiFi telemetry for Cleanflight with EZ-GUI and ESP8266

    Some time ago I have written a tutorial how to setup Bluetooth based telemetry link between Cleanflight and PC or smartphone. It’s simple and it works. But it has some disadvantages. For example, connection is very very slow and has a limited range: up to 10 meters. While it is enough to change PIDs before…

  • New PID controller for iNav

    If anybody keeps track of my posts about iNav flight controller software, he or she should notice that I like it very much. Guy nicknamed DigitalEntity did excellent job improving Cleanflight’s navigation modes. Maybe it is still not the same level as Pixhawk or Naza, but with this improvement speed those two are within reach…

  • Antennas: power loss on polarization mismatch

    Most people in RC hobby knows that receiver and transmitter antennas should match polarization. But what would happen if there was a mismatch? For example when transmitter uses linear vertical and receiver circular left hand? There would be a loss of power, attenuation. How much? Look at table below. Remember: -3dBi means half of power is…

  • How to flash firmware to ESP-01 ESP8266 WiFi module

    One can think that internet know everything about everything. Yesterday I’ve learned the hard way that is does not. It took me better part of evening to find a working way to flash firmware, any firmware, to cheap ESP-01 ESP8266 WiFi modules. There are many tutorials, most of them were just wrong in my case.…

  • 10 channels for FlySky FS-i6 radios

    This news might be not super fresh, but somehow it missed my attention. There is a good news for all owners of FlySky FS-i6 radios: there is an unofficial firmware that turns this cheap 6 channel radio into 10 channel one. Of course, there is a small catch, or even a few of them: All…

  • Better GPS for Cleanflight: iNav

    Cleanflight is an awesome piece of software for STM32 based flight controllers. But Cleanflight has one very serious flaw that makes its usage on bigger drones at least problematic. Cleanflight sucks in GPS and barometer support. Sucks a lot. It can handle Position Hold (somehow), Return To Home (barely) and Altitude Hold (oh man, up…

  • How to measure battery capacity with Arduino

    How to measure battery capacity with Arduino

    Battery capacity measurement can be useful in many situations. And it is not hard, only requires enough time to discharge battery completely with know resistance and a way to measure voltage in the circuit. Ohm’s law will to the rest: I = U / R Let’s say, we want to measure standard AA 1.5V alkaline…

  • VirtualWire support for Raspberry Pi

    FS1000A and XY-MK-5V 433MHz RF modules are very often first choice for cheap and dirty Do It Yourself wireless communication. Pair of those , allowing one way radio communication, const less than 3 dollars or euros. So they are really cheap. Limited range and transmission speed limits their real life usage, but simple assembly and…