hi , my project is to make a car , and this car should follow some tags .
I read a post on which one advised the use of an infrared led and three sensors. But after thinking, I figured that people will disturb these infrared no? Moreover the led will not work through the walls is not true??
You should provide more details..
- What kind of car? One you need to build? Using what? Anything you want?
IMHO.. I would start with that as a separate step in this project. Get the car made and working.
How does it work/move? 360 servos? motors?
How do you (manually) control it? Not at all? boht manually and 'tag mode'?
What are these 'tags'? Anything you define as a 'tag'?
How/where are tags placed? Is there 'many' of them.. provide/creating a 'trail' for the car to use/follow?
Lots of missing variables here IMHO..
I dont really see/envision a system where the car knows where to go?
'sensor' sees 'tag'...... and?
How does it know to go left/right/forward or back?
Are these 'smart' tags that provide some sort of direction/data to the car/system?
The people who use an IR emitter and three IR sensors are making a car that follows a line. This does not need to work through walls What are you trying to accomplish really?
I figured that people will disturb these infrared no?
No.
The wavelength of the IR used in electronics is way shorter than the thermal IR emitted by people and even hot things, until they start to glow red.
near IR as in the LED is just a shade of red light a bit too long a wavelength to see, but
can be focussed by ordinary lenses, and needs a source of illumination. Standard silicon
detectors can see it (unless filtered out as in many digital cameras).
far IR as in thermal imaging uses much longer wavelengths, and most of the optics needed
are expensive specialist parts. Thermal imaging cannot see anything unless there are temperature
differences, so is usually useless for navigation (but very good for spotting living things and overheating
electronics).
You are right, light including both sorts of IR does not travel through walls. You need microwaves or
gamma rays for that.
Or neutrons or neutrinos or cosmic rays etc...
Allan.