Looking for the right sensor

[ahab]

I'm building an autonomous rover (think DARPA 2005 on a 1/8th RC truck).

I'd like to get a fairly comprehensive scan of the ground in front of my bot to find a path. 3+ meter range and covering 135 + degrees, Sensors go from an array of 5 $40 IR sensors to $1300 Hokuyo scanning sensors.

I thought about making an array of IR sensors, but even using the 5 beam Sharp sensors I cost and wires would add up pretty quickly.

Is there a middle ground that I'm not finding?

[AndrewM]

Using a single or perhaps two sharp IR sensors (or sonar range finders) on a servo or two and sweeping the area.

[airman00]

if you feel like you are up to the challenge  , use two cameras and do image processing