Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: mwaau on July 06, 2010, 03:42:58 PM

Title: Making an IR emitter/detector
Post by: mwaau on July 06, 2010, 03:42:58 PM
Hi SoR Forum!

I am new at "robotting" and want to build my first small robot ??? Instead of just using the suggested two photoresistors for "obstacle avoidance"/"range detection" I consider making my own IR emitter/detector. But I got a bit confused when reading the "color sensor tutorial" because both the method with an IR emitter and an IR detector and the method with the three color LEDs combinded with the photoresistor was described.

Therefore I would like to know which of these methods you would prefer for "obstacle avoidance"/"range detection"?

And if the IR emitter/detector is prefered, what should the specification of the emitter and detector be, respectivly, when building the 50 $ robot?

I really hope someone can help  :)

Morten.
Title: Re: Making an IR emitter/detector
Post by: random robots on July 06, 2010, 06:46:50 PM
for obstacle detection, use a ir led/ reciever pair. for distance, buy a cheap ultrasonic sensor or sharp ir rangefinder.

hope this helps,
patrick
Title: Re: Making an IR emitter/detector
Post by: mwaau on July 07, 2010, 01:51:19 AM
Thanks for your reply,

However, I would like if you could get even more specific with the emitter/detector. For instance, what should the rated current/voltage be for the emitter/detector when using a 7 V power suply regulated to 5-6 V?
Title: Re: Making an IR emitter/detector
Post by: random robots on July 07, 2010, 05:54:26 AM
for the sharp ir, it uses 5v and so does ultrasonic. if you wanna make one, get a 5v 38khz center frequency reciever and make a 555 occilation circuit to a resistor and led. http://www.robotroom.com/Infrared555.html (http://www.robotroom.com/Infrared555.html) is a 555 circuit to drive an led at 38khz.

Hope this helps,
Patrick
Title: Re: Making an IR emitter/detector
Post by: Soeren on July 07, 2010, 07:26:16 PM
Hi,

I [...] want to build my first small robot ??? Instead of just using the suggested [...]  I consider making my own IR emitter/detector.
I don't wanna discourage your inventiveness, but this sound like a quick route to failure.
Crawl before you walk before you run...

Build the specified circuit for starters, then, when all works as it should, consider changing bits and bobs to improve (hopefully) the basic setup.


But I got a bit confused when reading the "color sensor tutorial" because both the method with an IR emitter and an IR detector and the method with the three color LEDs combinded with the photoresistor was described.
A really strong pointer to start simple and build some experience.


I really hope someone can help  :)
You can, by not trying to jump the fence.
Title: Re: Making an IR emitter/detector
Post by: mwaau on July 08, 2010, 06:17:43 AM
Actually, the reason why I ask for the specifications is that I am about to order a lot of components for the first robot. Of course my plan was to order some photoresistors and use these as a starting point, and at the same time ordering the emitter and transmitter so I wouldn't have to order them later when wanting to upgrade my robot.