View Full Version : help! Modulated ir sensors or ADCs n ir sensors!

10-15-2005, 12:25 PM
hi :D i m a newbie in robotics.. i plan to go for iitkgp compn. :D .. it requires me to make a linefollower n distance tracker robo..
cud u plz tell me whether i shud use shaft encoders wid dc motors or stepper motors with no feedback and only stepwise count..where 2 read abt using encoders..
mine is a line follower n distance measurer differentially driven robo..

also i need to use ir sensors .. shud i go for modulated ones or use ADCs with general sensors.. and do i get them easily..

10-15-2005, 01:48 PM
Hi DceRobo,
Thanks and heres the reply to ur PM:
1. You should use modulated IR to eliminate ambient light.
2. Shaft encoders are expensive. You can home brew a digital counter to measure wheel rpm. You can also use a Stepper motor as an encoder.
3. Some Printer motors have a built-in Tacho sensor. See sample at yahoo bangalorerobotics.
4. PC CPU fans too have a tacho sensor.

First, Read all articles here thro' search and http://www.roboticsindia.com/modules.php?name=News&file=article&sid=32
Post here if any problems and for help.

Good luck for the IITkgp !

12-03-2005, 12:48 AM
hi dude....

don go 4 all tat mess....
just have an ir emitter and receiver pair...
u can do tat without modulation...
ur receiver wil receive ir if the led is on top of the white line otherwise not...
so just program the logic tat way and if ur mechanical designing is perfect then u can realise the logic using simple nand gates.....
and for distance feedback.... use optocouplers