Guidelines for a line following robot with PIC16F877a

Dear All
I would like to start to build a line follow bot
Can any body guide me
My MCU is 16F877a

I think like this
Hopes to use PORTB with portb change interrupt
Hopes to use six Ir sensors to find line
Hopes to use two DC motors
Use L293 as DC motor driver

Please guide me with your ideas
Thank in advance

Re: Line following robot

Google for "Line Follower Robots" and, check this website: Line Follower Robot

Re: Line following robot

Scroll down to the bottom of this page and you'll find links to several other threads with a similar title.

I had a commercially made line follower robot called Movit. It only used 2 photosensors.

Re: Line following robot

for tutorials lookout here

DIY Live » DIY Archive » DIY Line Following Robot 2
FailureBot 5 - A Line Following Robot

Dear All
I red all website that you provided
so I decided to use LM324N as sensor driver
LN293 as motor driver
and decided to use 8 sensors

can I know any programming Technic using assembly

---------- Post added at 23:37 ---------- Previous post was at 23:12 ----------

Dear Bradthered,
Thank you very much for reply
using two sensors. I think, it may be swing the bot
how do you manage the swing ?
can I have more advice

PA3040 said:

Dear Bradthered,
Thank you very much for reply
using two sensors. I think, it may be swing the bot
how do you manage the swing ?
can I have more advice

Click to expand...

I no longer have the robot, but I remember it used an op amp (maybe two op amps) to sense the difference between two light sensors. These were mounted side by side, resting on the floor in front of the robot.

When one sensor saw dark, the other saw light. The op amp responded to keep the sensors equally illuminated. In the one case it turned on the lefthand drive motor.

In the opposite case it turned on the righthand motor. Response was fast, and the robot fishtailed a little from side to side as it travelled. It could go a couple inches per second.

There is the need for the robot to be able to acquire a line. This means allowing a sensor to see dark and yet not change the direction the robot is going. As I think about it, this was designed to happen naturally. No need to make the control circuit switch to 'acquire' mode. Anyway I remember that the robot would drive in circles until a sensor picked up a dark line.

We have developed a line follower robot with pic 18f series Which uses only two infrared transceivers .it has better controll and live programing feature.I think there is no nessecity for 8 sensors.with two sensors we can make a highly accurate one

Dear S.P.S
Thanks for reply. my concern is using two sensor it may be swing
Am I correct

It may be;but in the case of our robot I can say that it doesn't happened yet .probably the motor speed and chasis alignment determines it,but using differential speed control we can make a perfect line follower robot with two sensors.I gaurantee it.it's not much complex and reliable I think;

thanks for reply S.P.S
can I know the sensor drive IC that you have used

We have designed an IR transceiver for these purpose .I think the simplest method to trace the track accurately is by the use of IR transceivers .there are no more sensor driving circuit is needed just a 555 astable multivibrator and a tsop receiver

Thanks S.P.S
can we use PWM for motor drive

Definitely,
It is the best suitable method for these type of applications.
In the case of pic there are PWM contol registers which made it much easier!

Dear S.P.S
Can you guide me on that how use PWM for line follow bot
any pseudo code