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BLDC motor Electronic speed controller

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Apr 19, 2015
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Hey guys.

I am doing a simple something... Which is a qudcopter basically just coz I always had a fascination to things which fly.... And so I have seen many sites referring and tutoring about how to do these things using arguing etc.
I intend to this DiY by using pic microcontroller since I have got the hang of using it and it's fun since we learn a lot.. So here's the problem which I have been encountering on many tutorials etc...
They advise the usage of cheaply available BLDC motors which require an electronic speed controller (ESC) and in many of the tutorials about ESC they mention about giving input to the receiver etc... Can anyone help me to understand this more clearly as in the ESCs input and output (where does it go to etc).

Thank you in advance

For balance, 4 sets with two counter rotating blades driven by sensing a sum and difference current of all 4 motors is required with half bridge low Rdson drivers with controlled deadtime during commutation, for each motor.

Quadcopters are symmetrical and embody the simplest principle of operation for controlling roll, pitch, yaw and motion.

Simply varying the speed of each of the motors provides full 3D motion and rotation and hover capability.

Upward Force is less proportional to current as it is including inertial forces for changes in rotor speed and air eddy current losses with rising f. Gyro feedback is essential for motion control with current feedback and smart signal processing.

Then for smarter navigation, other feedback is needed like GPS.

i suggest you reverse engineer an inexpensive Quad to fully understand all the transfer functions of inputs and outputs before you begin to DIY as you have many man-decades of R&D to learn.

A simple quadcopter consists of 4 motors (2 clockwise + 2 counterclockwise)
Every motor has an adjacent ESC that's responsible for it's rotation speed.

The 4 ESCs are connected to a "receiver" - every ESC to a different receiver channel.
The receiver controls the rotation speed by a PWM (constant frequency, variable duty cycle) signal.
Gyro's and Accelerometers are used as sensing elements for a feedback loop to adjust PWM signal (and hence the rotation speed) many many times per second. This keeps the vehicle flying stable.

I understood it now... Thank to u all... Will ask any doubt once I start reverse engineering an inexpensive quad...

have you started reverse engineering ? because ill suggest you not to, cause i already know enough about bldc and it's control circuit so you can make it at home,but you will need smd rework station, in bldc control most complicated thing is software not hardware, also i'm from India and i want to know form where did you get BLDC motor and what is its price?.

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