I need a little help how to build a line follower robot just using a logic gates, because our teacher wants the harder way around he doesnt like to used micro-controller. Also the robot will be Added with a sensor to count the blocks the robot encounter in the track. Can any one give me ideas where to start. That can be build for a week....thx

 

It shouldn't be so difficult as it sounds. If I were you I'd start with the control of the motrs, then the sensors, after that the constuction of the robot and then I'd sit and try to sort out the problem with the LogicGates.
I suppose that the sensor for the line-following will be 3 ir-diodes and 3 ir-recievers. Depending on the position of the line one of the 3recievers will trigger and you will be able to find the needed direction to follow the line. So the left reciever makes the robot to turn left, the right to turn right and the middle one to move forward. And if u have two motors to drive the robot it will be very very easy, almost as a "hello world"
I hope the info would be useful
Svetlin

 

well how to make a bot using logic chips.... I hopw you can use analog comparators as well (op amp).

anyway take 4 sensors. Light dependent resistors are the best. and then take 4 superbright red LED's. and make those LED's shine on the LDRs. \/ alignment (light reflects from floor). and also shield the whole system from all amb. light with cloth or tape or whatever...

Anyway that done let's move to the sensor reading part... Connect those sensors to the analog comparator inputs. right to comparator1(C next time) + input and one of the middle ones to C1-, then the other middle one to C2- and the left one to C2+ (you might want to switch the inputs. haven't tested it so don't know the outcome). and the other sensor legs (not connected to C1/2) to Vcc (+5v). then take a 4x10k resistors and connect them from GND to C1+- & C2+- legs (on all legs as pulldowns).

And you have the sensors done... Next take a good transistor (say BC618) and connect it to the C output. one for each motor. also connect a 180ohm (or alike) resistor between the transistor base and the Comparator output. (just in case). and then slamm the motors to the transistors and a way you go a lot of trimming and tuning needs to be done, but this is ht funnest and most educational part of the robot building


And remember, this is just one way of doing it... you could use 100 other ways to do it. but I would appreciate, if you at least considered mine as it took so long to write

anyway good luck

If you have any questions, you know where to find me

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Souper man

what you could do is hook up photoresistors for sensors, and have them go into inverters. Have the 2 inverter outputs go into a and gate, and in turn power 2 transistors to turn on the motors/LED indicators. Wa la!

 

It's easy to build, the line tracer robot with the photo transistor as sensor color of the line. You can use two photo transistor and two led for sources the light. If the sensor reads white, so photo transistor is steady high and if sense of black the photo transistor is steady low.
The output photo transistor as input comparator as lm 339, lm 324 etc. Output of comparator can drive H bridge for motor driver.
Its, very easy Ok

 

Please check the date on threads prior to replying. The thread was last posted to on 3rd May 2007. It is stale.

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Hi,
With no disrespect meant, replying late to an old thread to me sounds like a good thing.
meaning that those of us who came in a year later, can fire up an old debate again and refresh it with newer more current detail, besides, isn't this what a community board is for, collecting opinions and points on issues?

 

You'll find that 90% of the time, it is someone who for some reason can't figure out how to start their own thread but has figured out how to reply to threads and is trying to hijack the thread. And the thread tends to die anyways after a while anyways since no one responds to it anymore.

Necromancer

 

Hi I nedd to build a robot that avoids obstalces that uses logic gates

Any ideas?:

 

how do ypu post a new thread

 

UM Yeah why don't you tell us how to start a ne thread!!!!!!!

 

13th January 2009, 02:37 AM #8 (permalink)
dknguyen Why don't you tell us how to star a ne thread selfish brat!!!!

 

You need to

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One question guy...just how the He double hockey sticks do you start a new thread!!!

 

spamming other threads is not acceptable.

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