Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: RoboDoc2008 on February 08, 2009, 10:45:24 PM

Title: Line Following Robot: How do I Improve IR sensor Range?
Post by: RoboDoc2008 on February 08, 2009, 10:45:24 PM

recently I have been building a simple robot that will follow a black line on the ground, using 3 IR LED sensors. The range of the sensors is only about 10mm (0.4") and I would like 20 increase tis to about 2.5mm (1").
At present both IR emitors and IR recievers are connected to 470 R (470 ohm) resistors, an recieve a Maxium input of about 5V DC.
The Batteries supply 5V DC to the entire Robot, this voltage drops very quickly to about 4.7V DC.

Circuit Diagram part List
IR sensor: D1, D2, D3
470R resistor: R1 - R7
5mm LED: D4
Input Voltage: 5V DC

How do I increase the range of the IR senors to 2.5mm (1") ?
Is there a way to keep a constant voltage supply to the IR sensors using Capacitors ?
Any suggestions would be great!

Title: Re: Line Following Robot: How do I Improve IR sensor Range?
Post by: pomprocker on February 09, 2009, 12:13:10 AM

If you pulse the IED instead of leaving it constantly on, you can give it more current, which should give you more range.

Title: Re: Line Following Robot: How do I Improve IR sensor Range?
Post by: Admin on February 15, 2009, 05:21:44 AM

Several methods . . . give it a higher voltage . . . or use a voltage amplifier on the output . . . or get complicated and do frequency modulation/filtering.