Maneuvering a Home Enviornment

[airman00]

Which sensors will be the best suited for a home environment. I have used IR sensors before but they are not really precise. I need to be able to detect when my robot is too close to an object or a wall( less than 6" away).
Will IR be suitable, or will I have to go with sonar. The reason I don't want to go with sonar is because the detection area is very wide and sonar is really expensive. IR is cheaper but not accurate readings.
Can IR detect ranges of 6" or less accurately. Also, will the IR sensor be more accurate for some things in a home environment.

[Gertlex]

I haven't personally used IR, but logic follows that if people use it so often on small robots, they're probalby going for more accuracy than 6 inches.  It should work fine, unless your walls are sheets of shiny metal

[airman00]

I have a fairly large robot (21" by 19"). Will the IR be able to supply the robot with enough information to maneuver around a home?

[Gertlex]

I have a fairly large robot (21" by 19"). Will the IR be able to supply the robot with enough information to maneuver around a home?

As long as you provide enough sensors to cover all sides and shape (i.e. corners of a boxy robot, if that's your case)

Though I'm not sure about chair legs.

Are limit switches disguised as decent looking bumpers out of the question?

[airman00]

I don't want bumper switches . Non tactile sensors only.
But I'm still not sure about using IR. Is IR suitable for the home, even though a house may have many colors in it?

[Del]

Both IR and Sonar have their strengths and weaknesses.
The best solution might be to use both so that one type of sensor can
make up for the weaknesses of the other type of sensor.

In my limited experience, sonar seems to work better than IR.
As you mentioned, IR can miss detecting darkly colored objects.

Hope that helps a little.

[Admin]

Dont forget that it depends a lot on:

1) Your home
2) Size of robot
3) Tasks that robot must perform

And remember, no point in having 99% sensor accuracy if your robot will function with 25% . . . Decide first on what error level is acceptable, then work from there on deciding sensors . . .

[HDL_CinC_Dragon]

Why not just have multiple sensors?

Apparently though, something as simple as a bed sheet can throw off a sonar sensor. Myth busters tried it out :-p

and for like a failsafe sort of thing, why not just have limit switches on all 4 sides so that if it hits something, it just goes back to whatever position it was in 2 or 3 seconds before and then tries again?

[airman00]

All i need to know is when there is an object around 6 inches away or even closer. All the circuit will be is a comparator and the IR sensor. Once it goes over a certain level the robot knows to avoid an object in front.
Can IR effectively notify the robot of an object that is around 6 inches or less, in front of it?

[Admin]

All i need to know is when there is an object around 6 inches away or even closer.

This requires like zero accuracy . . . sonar would be best . . .