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Om Shah
Om Shah

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FeedForward and FeedBack Control

What the F**K is that?

Well kiddo chill out! I'll teach you something cool!

Intro

These are the concept of Control theory which are used in robot or making autonomous cars/anything.
I learned this while making robots for my team to compete in the world's biggest Robotics competition called Vex Robotics.

Let's take an example, let's say your have a Remote control car. Well how will that car move? By giving inputs, in this case with the help of remote. You pushed both joystick forward, the car will gain speed and move straight.

Example Image

Assume you don't have that cheap cars but a cool car that can move by itself. Here, there is an reference that says the bot what to do.
But we are in a real world and not in your dreams so things are not perfect here! We get some disturbances while we drive or while it drives itself.

FeedForward Control

FeedForward Control

This is called FeedForward Control. The google definition is: A feed forward (sometimes written feedforward) is an element or pathway within a control system that passes a controlling signal from a source in its external environment to a load elsewhere in its external environment.
I know you didn't get that definition here you go:
FeedForward control passes a defined input to the system(your remote control car) to do something.

FeedForward Control is good if it's in your dream world but not in human world. Well, that's not true. It is good for task that doesn't have many disturbance. But your car have disturbances like your stupid brother coming in it's way or the surface it is driving on or maybe the battery which affects the motors. What do we do in that case? We have FeedBack Control which takes the error/noise and sends it back to determine further movements.

Ok so there is an disturbance. Now what? The disturbance is understood and sent back to the controller to make determine the further movement. We can get deep in this but for now just say FeedBack control will make it loop to solve the error itself.

FeedBack Control

That's all for now! Comment any question you have or anything you feel I said something wrong or want to share something related! Happy to learn more!

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