what is pid controller

What is a PID controller and how it works?

The whole FPV hobby, and especially multirotor drones, work only thanks to control theory and PID controllers. They are the only thing that separates chaos and immediate flip-over from a stable flight. A regular multirotor has at least 3 PID controllers. If you enable any mode with self-leveling, the number goes to 6. Any GPS assisted mode increases the number to at least 12.

Of course, the PID controllers we think when we think about when we say about multirotors, are Rate PID controllers. They keep our drones stable by keeping angular velocity at desired levels. And usually, they are the ones that have to be tuned to achieve a nice, smooth and stable flight.

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Drone and RC airplane motors – everything you wanted to know but you were afraid to ask!

Today, let's have a nice talk about brushless electic motors we use in the RC hobby. Both on airplanes, as well as on drones. In this video we will discuss:

  • motor size
  • motor KV and rotation speed
  • KV versus KT as motor constants
  • stator and rotor
  • number of coils and poles
  • winding
  • phases
  • airflow and cooling
  • does a motor care about rotation direction
  • how to change the rotation direction of a motor
  • shaft and hub
  • mounting holes spacing
  • how not to fry your motor right away

Your first 7-inch FPV drone

I love 7-inch FPV drones and during the last year, they were my most used FPV gear. For freestyle, cinematic, cruising and long-range. I currently own 3 7-inch FPV drones and 4th one in the assembly process.
I think of myself as a 7-inch expert. I’ve wasted enough money and equipment to know what works and what does not work well with 7-inch propellers.

TBS Source One 7-inch FPV drone

If you are thinking about building your own 7-inch FPV drone, here are some tips that might save you a lot of time and a lot of money on wrongly chosen equipment. Read More

Ohm’s Law for beginners

Yes, Ohm's Law for beginners, not for dummies. I do not want to offend anyone and if you are interested in things like Ohm's Law, you are clearly not a dummy.

In this video, we will talk briefly about what Ohm's Law is and how it influences everything connected with electricity. That it describes the relationship between voltage and current. That when you increase the voltage, you increase the current as well. And that voltage and current combined together give you power! And that doubling the volatge, you increase the power 4 times!

How to make tape hinges

If you have a foamie or want to build your own airplane, this skill is a must: how to make tape hinges! In this example, we will make a tape hinge between to pieces of Depron foam board. But it can be any other kind of flat material: balsa, plywood, metal, plastic. The basic idea is always the same: two strips of adhesive tape on both sides

FuriousFPV True-D X firmware update via Bluetooth from your smartphone

Today something that was supposed to be a very fast and nice experience but turned out to be quite stressful: how to update the firmware in FuriousFPV True-D X diversity module using Bluetooth and Android or iPhone app. It “almost” worked out of the box. Luckily True-D X was not bricked during the failed firmware upgrade!

Manage your OpenTX trims like a PRO!

Almost all RC radio transmitters (Jumper, FrSky, Nirvana and all other OpenTX radios) have trims. When flying classical airplanes, their usage is obvious: you trim your airplane with trims. When using any flight controller or stabilization, they immediately become useless. Trimming has to happen on flight controller (INAV, Betaflight, Pixhawk, Ardupilot), not on the radio itself. Luckily OpenTX allows you do some tricks with trims:

  • disable trims so they will not accidentally break anything
  • use trims as 2 position switches and assign them to any radio channel
  • use trim to reset flight and timers in OpenTX