INTRODUCTION

1st of all I am not a teacher or something, just mere student interested in robotics. So if anything goes wrong please point it out. :) And I might not be that systematic, so adjust… :P


Okkk then lets start…
The 1st word that comes to the mind when we speak of robotics is motors, switches and logic… Motors to move or do some stuff, switch to run the motors and logic to tell the bot when to switch on the motors. We will discuss the logic part in the end.
And we will be starting off with switches.

SWITCHES
Switches can be made using just connecting wires and other electrical materials. But the kind of switches I am referring to are electronic switches which are called transistors (NPN and PNP).








When the switch is closed a small current flows into the base (B) of the transistor. It is just enough to make LED B glow dimly. The transistor amplifies this small current to allow a larger current to flow through from its collector (C) to its emitter (E). This collector current is large enough to make LED C light brightly.

When the switch is open no base current flows, so the transistor switches off the collector current. Both LEDs are off. (click the images for a better view.)