sckooi

hi... i wish to ask some line sensor problem. now i do AGVs project. what kind of line sensor can auto adjust the sensitivity? for example, i wan the sensor auto tune the sensitivity when face the floor colour is almost similar with line colour. And show me the circuit diagram for line follower sensor.
Thx a lot....

NightFalcon90909

Well I'm sure this is possible,l but I'm not sure how to do it automatically. Manually, you could use a comparator, and could just adjust the voltage going to the comparator that the input from the line would be compared to.

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If it is broken, let's fix it.
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Krumlink

Rules to follow when posting:

Proper Punctuation
No Text Speak
No using Plz, thx or Improper language, aka the (...)
Also, what have you done so far? Nobody is wanting to help you when you ask "Show me complete circuit thx". That does not show how much effort you have put into it. You should get a zero on your project.

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NightFalcon90909

One more rule to follow when posting:

-Always try to be kind to newcomers. Aim for an encouraging, helpful tone. Otherwise, no one will want to stay.

For such an active member, Krumlink, I am surprised.

The ellipsis (...) is a perfectly legal English punctuation mark, and it is unfair to discriminate against someone because they write "ur" instead of "your." He said much more than just "show me a complete circuit thx." He mentioned that he was trying to design a circuit that would automatically adjust its sensitivity. That is a valid and interesting proposal.

Krumlink, try to be kind!

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sckooi

NightFalcon90909 thank ur reply...

http://www.kmitl.ac.th/~kswichit%20/LFrobot/LFrobot.htm

i will use this line follower circuit as show link above. but not sure that circuit can work or not? is it i can use that variable resistor (inside the line follower circuit) to adjust the sensor sensitivity? What type of comparator need to use? LM324? and what types sensor also... please advide me which model? thanks...

NightFalcon90909

That circuit should work fine.

As far as sensors, you could definitely set up the sensors as shown in the picture on that page-



The 20 K var resistor there will let you adjust the sensitivity- read up on comparators if you are interested in how, and you probably should be if you are going to have to explain this project to anyone ;-) It's better to understand how comparators work anyway, you'll use them a lot. For the comp chip, I'd say use the LM339.


For the sensors, you could use the sensors that he used-



TX would be a infrared LED, and RX would be an IR Transistor.


You could also buy an IR LED and an IR Transistor in a package already... that is easier to interface.

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If it is broken, let's fix it.
If it is working, let's make it better.

kemo0o

I THINK THAT YOU WILL FIND HELP THERE
http://www.ikalogic.com/cat_robot_navigation.php

IT HAS ALOT ABOUT ROBOT NAVIGATION

sckooi

hi...
i trial to construct the circuit as show above. i found my sensor without any response. why?
is it sensor angle problem? is it i can test the sensor without the assembly code? can teach me how to test the sensor after build the circuit? thanks...

NightFalcon90909

Debugging time eh?

Make sure everything you have is hooked up to an appropriate amount of power.

Shine the IR LED directly at your receiver. If it doesn't work, you have a faulty receiver.

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ikalogic

Implementing auto adjustment is quite a challenge, because not only you have to be able to 'read' the current condition, you also need to have a mean of changing the threshold of your sensor, in other words, you need a DAC and an ADC! good luck!

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check my electronics and robotics page: http://www.ikalogic.com/