We are developing a robot platform.
We are already using Hokuyo URG-04 Laser range finder + Encoder as our sensors. There is little drift in odometry.
Now, There can be a case of steps going down where robot may fall inspite of having proper map and indicating unknown area for steps.
So, we are planning to use IR, which can be set at one end of first steps throwing rays horizontally parallal to step. Now if robot comes near by then laser range finder will cut the ray of IR. So, that indicates there is a down step.
My question is: Will it be possible for Laser range finder to detect the beam of IR?
Second question: We are planning to use IMU sensor for effective localization. Which is best IMU one can suggest?