[joshyboy9987]

I was thinking about this a little while myself. We're thinking of having a similar system for our robot in this year's competition. What if you used an Ultrasonic sensor to do a wide sweep, and then if it found anything unusual, you could use an IR or laser rangefinder to do a fine resolution sweep? You could have all of that stuff mounted on servos too, just so that you could get the direction the obstacle is in.