Circuit Diagram:
Parts Required:
- BC 108 Transistors x (2)
- N4148 Diode x (2)
- 10K potentiometer x (2)
- LDR x (2)
- DC geared Motors x (2)
- 9V Battery
Bread Board Arrangement:
One of the most disadvantage of making this circuit is that with only transistors its difficult to control speed of motors. The most common, efficient and reliable method of controlling motor’s speed is through PWM(pulse width modulation) which make the transistor rapid on/off switch. Click here to see: PWM based Line Following Robot using three 555 timers.
Step by Step Procedure to make this Circuit:
Stripboard Version:
By taking advantage of this small and easy circuit, dont miss to make a Strip board version. And by making this little easy solding circuit you will be able to reduce the structure of your robot and make it precise. Best part is, when you use these jumpers then you dont have to make the sensor strip which is commonly made and used in LFRs. I also added a ON/OFF switch in this strip board, so that I have to plug in and plug out the Battery while tuning the sensitivity of LDRs. The reason I left the space beside the circuit is for keeping the 9V battery over it =)
In our case, the method we are using is called as “differential drive steering method”. It is Jerky and shaggy but still works fine! Here is the picture taken from emicro.com which defines this differential drive method properly.
The BC108 transistors are designed to be used in their linear region so that the collector current passed through the DC motors will vary according to the base current, which is controlled by LDR+10k trimpot. And like this, DC motor will be given current according to the light intensity received by LDR.
The trimpot is used to adjust the DC motor speed, and N4148 is used to protect the BC108 from EMF generated by motor inductor when it switches off.
The material in the for the track might be different for every other roboticist. So we can always have different track’s route by simply varrrying the 10k
No comments:
Post a Comment